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1.	Pettersson, Dan, et al. (författare) Influence on crack development in concrete structures from imposed strains and varying boundary conditions 2002 Ingår i: Construction and Building Materials. - 0950-0618. ; 16:4, s. 207-213 Tidskriftsartikel (refereegranskat)abstract Crack development due to imposed strains in different types of concrete structures and with varying boundary conditions is studied in order to improve control of cracking. A previously developed two-dimensional FE-method is used, with closing forces in cracks concentrated to spring elements. Temperature changes are used as load, and the calculations are performed stepwise with opening of nodes and implementation of spring elements. The FE-method has also been used to study crack widths and crack spacing for a wall fully restrained at the bottom. It is shown that the type of restraint has significant influence on crack widths. For structures with restraint along the length direction the restraint effectively facilitates distribution of cracking, similar to a wall fully restrained at the bottom. (C) 2002 Elsevier Science Ltd. All rights reserved.
2.	Björk, Folke., et al. (författare) Degradation of components in flooring systems in humid and alkaline environments 2003 Ingår i: Construction and Building Materials. - 0950-0618 .- 1879-0526. ; 17:3, s. 213-221 Tidskriftsartikel (refereegranskat)abstract Constituents from products that are used in the flooring on a concrete slab such as carpets of plasticised PVC and water-based adhesives sometimes degrade in an alkaline and humid environment. The concrete itself could be such an environment. In order to examine the effect of different levels of alkalinity and humidity on the mentioned products a specialised procedure was developed. By this procedure it was possible to imitate the effect of an environment of alkalinity and humidity corresponding to a recently produced concrete slab on different substances and also collect volatile degradation products produced. Degradation of some of the constituents was dependent on the levels of alkalinity and humidity, although there were significant differences in the possibility to resist the environmental factors. For some of the components, an increase in alkalinity resulted in a much higher production of degradation products even when the relative humidity was kept on a comparatively low level. The results give basis for a recommendation not to adhere plastic floorings directly to a recently produced slab of high-quality concrete because the alkaline material in the concrete could cause degradation.
3.	Björk, Folke., et al. (författare) Measurement of alkalinity in concrete by a simple procedure, to investigate transport of alkaline material from the concrete slab to a self-levelling screed 2002 Ingår i: Construction and Building Materials. - 0950-0618 .- 1879-0526. ; 16:8, s. 535-542 Tidskriftsartikel (refereegranskat)abstract A test procedure for measurement of alkalinity for cementitious materials that is, reliable, simple. and only needs a small amount of sample, was developed and applied to check whether transport of alkaline material from a concrete surface to a covering screed can result in a detectable increase in pH-value. It was found that any transport of alkaline material from a rather humid concrete did not increase the level of alkalinity (or pH-value) of the screed covered with a carpet. It was noted that carbonation Occurred gradually from the surface and inwards when the materials were exposed to ambient air. For the prisms, of 95%, RH pH-value in the concrete surface increased with time. A transport process that allows hydroxide ions solved in the pore water in the concrete to diffuse towards the carbonated surface and thus give an increased pH-value, can explain this.
4.	Granne, F., et al. (författare) Joints between roofing felt and sheet metal flashings - short- and long-term tests 2000 Ingår i: Construction and Building Materials. - 0950-0618 .- 1879-0526. ; 14:07-jun, s. 375-383 Tidskriftsartikel (refereegranskat)abstract The adhesion between roofing felt and sheet metal flashings has been measured and analysed and test methods for this have been developed. Both bituminous and polymeric roofing felts have been used. The steel has been PVC-coated galvanised steel sheets and the bituminous roofing felts have been of both SBS and APP modified type. All the joints have been made with heat welding. The tests show that it is possible to obtain joints with sufficient strength using the contractors ordinary welding procedures.
5.	Granne, F., et al. (författare) Wind load resistance tests of heat-welded joints between roofing felt and sheet metal flashings 2003 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 17:5, s. 319-324 Tidskriftsartikel (refereegranskat)abstract The wind load resistance of joints between roofing felt and sheet metal has been measured in a wind uplift chamber. Both bituminous and polymeric roofing felts have been used. The sheet metal has been PVC-coated galvanised steel sheets and the bituminous roofing felts have been of both SBS and APP modified type. All the joints have been made by heat welding. The tests show that peeling is the dominating process in the failure of joints during wind load.
6.	Täljsten, Björn (författare) Strengthening concrete beams for shear with CFRP sheets 2003 Ingår i: Construction and Building Materials. - 0950-0618 .- 1879-0526. ; 17:1, s. 15-26 Tidskriftsartikel (refereegranskat)abstract The method of strengthening concrete structures with FRP composites has existed for over a decade; the most common way to strengthen structures is in bending, but also wrapping of columns is quite common. There are also needs for strengthening concrete structures in shear, for example concrete beams, slabs, columns, etc. A typical structure can be a parking garage. However, strengthening concrete structures for shear is not as common as for bending and confinement. This paper presents examples to strengthen concrete beams for shear. First traditional strengthening methods are presented briefly, then the use of CFRP (Carbon Fibre reinforced Polymers) composites for shear strengthening is presented. Tests on beams strengthened in shear with CFRP sheets are presented and a short presentation on how to design for shear strengthening with CFRP is given. Furthermore, a field application of a parking slab strengthened for shear with CFRP unidirectional fabric is presented. The laboratory tests show the importance of considering the principal directions of the shear crack in relation to the unidirectional fibre. The field application shows that it is easy to strengthen existing structures for shear with CFRP fabrics.
7.	Adamopoulos, Stergios (författare) Acoustic emission monitoring of wood materials and timber structures: A critical review 2022 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 350 Forskningsöversikt (refereegranskat)abstract The growing interest in timber construction and using more wood for civil engineering applications has given highlighted importance of developing non-destructive evaluation (NDE) methods for structural health monitoring and quality control of wooden construction. This study, critically reviews the acoustic emission (AE) method and its applications in the wood and timber industry. Various other NDE methods for wood monitoring such as infrared spectroscopy, stress wave, guided wave propagation, X-ray computed tomography and thermography are also included. The concept and experimentation of AE are explained, and the impact of wood properties on AE signal velocity and energy attenuation is discussed. The state-of-the-art AE monitoring of wood and timber structures is organized into six applications: (1) wood machining monitoring; (2) wood drying; (3) wood fracture; (4) timber structural health monitoring; (5) termite infestation monitoring; and (6) quality control. For each application, the opportunities that the AE method offers for in-situ monitoring or smart assessment of wood-based materials are discussed, and the challenges and direction for future research are critically outlined. Overall, compared with structural health monitoring of other materials, less attention has been paid to data-driven methods and machine learning applied to AE monitoring of wood and timber. In addition, most studies have focused on extracting simple time-domain features, whereas there is a gap in using sophisticated signal processing and feature engineering techniques. Future research should explore the sensor fusion for monitoring full-scale timber buildings and structures and focus on applying AE to large-size structures containing defects. Moreover, the effectiveness of AE methods used for wood composites and mass timber structures should be further studied.
8.	Addassi, Mouadh, et al. (författare) Reactive mass transport in concrete including for gaseous constituents using a two-phase moisture transport approach 2020 Ingår i: Construction and Building Materials. - : Elsevier. - 0950-0618 .- 1879-0526. ; 232, s. 1-14 Tidskriftsartikel (refereegranskat)abstract This article presents the further development of a tool for multi-phase reactive mass transport modelingfor durability estimation of cement-based materials, by the addition of the gas phase, adopting a trulyseparate two-phase moisture transport approach. The governing system of equations are based on phys-ically sound hybrid mixture based version of the Poisson-Nernst-Planck system of equations includinggaseous transport in the air-filled space, ionic transport in the liquid phase, electro-migration of ionicspecies, a two-phase moisture transport model, and sorption. The addition of the gas phase and thetwo-phase moisture description enables the user of the model to investigate individual and combinedeffects of different degradation processes in unsaturated systems. The altering of hydrated cement underthree different environments were studied representing an accelerated carbonation environment, a sub-merged marine environment and a cyclic drying-wetting zone in a marine environment, to illustratesome of the model’s capabilities.
9.	Al-Ayish, Nadia, et al. (författare) The influence of supplementary cementitious materials on climate impact of concrete bridges exposed to chlorides 2018 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 188, s. 391-398 Tidskriftsartikel (refereegranskat)abstract In order to reach a specific service life of reinforced concrete structures a certain cover thickness is needed. At present, this is regulated by national standards that also limit the amount and type of supplementary cementitious materials in different exposure environments. The regulations do not, however, consider the actual durability performance of concrete with supplementary cementitious materials. As a consequence, the LCA results might be misleading. This paper shows the environmental impact of concrete with supplementary cementitious materials in chloride environment considering their specific performances. Prescriptive and performance based service life prediction models for chloride ingress are applied and compared.
10.	Alhede, Andreas, 1996, et al. (författare) A two-stage study of steel corrosion and internal cracking revealed by multimodal tomography 2023 Ingår i: Construction and Building Materials. - 0950-0618. ; 394 Tidskriftsartikel (refereegranskat)abstract Modeling of corrosion-induced cracking is limited by lacking knowledge on the behavior of corrosion products. In this work, the corrosion and cracking processes were experimentally investigated in 3D at two different stages. The processes were measured at micro-structural scale, applying nondestructive neutron and X-ray computed tomography in two scans at different stages in the corrosion process. A method to evaluate the average volumetric strain of the compressed corrosion layer was proposed and displacements in the concrete matrix were measured. Strain localization revealed cracks not directly visible in the images. Multimodal tomography demonstrated to be an effective method for investigating steel corrosion in reinforced concrete.
11.	Amiandamhen, Stephen, 1983-, et al. (författare) Recycling sawmilling wood chips, biomass combustion residues, and tyre fibres into cement-bonded composites : Properties of composites and life cycle analysis 2021 Ingår i: Construction and Building Materials. - : Elsevier Ltd. - 0950-0618 .- 1879-0526. ; 297 Tidskriftsartikel (refereegranskat)abstract This study investigated the properties and sustainability of cement-bonded composites containing industrial residues such as wood chips, tyre fibres and biomass combustion residues, i.e. bottom ash (BA) and fly ash (FA). The effect of cement-to-raw material (wood/tyre fibre) ratio (C/RM) and the aggregate content (BA and FA) on thermal and mechanical properties of the composites were investigated. Scanning electron microscopy (SEM) and life cycle analysis (LCA) were also conducted. The results revealed that as the aggregate content increased in wood composites, the mechanical properties also increased. The mean thermal conductivity and volumetric heat capacity of tyre composite samples were 0.37 W/mK and 1.2 MJ/m3K respectively, while the respective values for wood composite samples were 0.29 W/mK and 0.81 MJ/m3K. SEM analysis showed adequate bonding between wood/tyre fibres and cement matrix. LCA revealed that the materials share of the total primary energy use was about 60% for all analysed composites. © 2021 The Author(s)
12.	André, Alann, 1980, et al. (författare) Application of fracture mechanics to predict the failure load of adhesive joints used to bond CFRP laminates to steel members 2012 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 27:1, s. 331-340 Tidskriftsartikel (refereegranskat)abstract The use of bolted or welded elements to upgrade metallic structures has been a common practice for many years. Moreover, the use of adhesively bonded carbon fiber reinforced polymer (CFRP) laminates, as an alternative method, has attracted a great deal of attention in recent years. One important aspect of the design of adhesive joints used to bond CFRP laminates to steel substrates is the determination of the properties of the CFRP/adhesive/steel interfaces, which have not yet been established in codes or standards. The purpose of this paper is experimentally to determine the fracture properties of the adhesive material and to evaluate the accuracy of numerical methods using this information, in order to predict the strength of adhesive joints in steel members bonded with CFRP laminates. The results from four series of experimental tests are compared with numerical results and discussed in terms of load-bearing capacity and failure modes.
13.	André, Alann, 1980, et al. (författare) Compression failure mechanism in small scale timber specimens 2014 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 50, s. 130-139 Tidskriftsartikel (refereegranskat)abstract Understanding the failure mechanism of wood loaded in compression parallel to the grain has been shown to be an important parameter in the design of timber beams strengthened with fibre-reinforced plastics (FRP). In this paper, a constitutive relationship for wood under uniaxial compression load parallel to the grain was determined experimentally. Several parameters, such as silviculture, moisture content and radial position in the log in relation to the pith from where the specimen was sawn, were considered. Small clear-wood specimens were used. The strain localisation in the failure region (kinkband) was monitored using the digital image correlation method. The results show that silviculture and moisture content are two very important parameters which influence the compression failure mechanism. Furthermore, there is a significant difference in behaviour between specimens from the juvenile region of the log and specimens from mature wood. Based on experimental results, two numerical models were built, considering either a global or a local constitutive relationship. It was demonstrated that both numerical models yield accurate results and that, depending on the experimental equipment available, a constitutive relationship could be extracted and used as input in these numerical models. (C) 2013 Elsevier Ltd. All rights reserved.
14.	André, Alann, 1980, et al. (författare) Compression failure mechanism in small-scale wood specimens reinforced with CFRP: An experimental study 2013 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 41, s. 790-800 Tidskriftsartikel (refereegranskat)abstract The optimal use of Carbon Fibre Reinforced Polymer (CFRP) when strengthening timber beams loaded in bending involves considering placing the reinforcement on both the tension and the compression side, in order to utilise the ductile compression failure of the wood to the full. In this respect, a knowledge and understanding of the compression failure mechanism of the timber/CFRP system becomes a point of paramount importance. However, no testing method specific to the compression loading of small wood specimens reinforced with CFRP is currently available. This investigation focuses on the experimental developments of the geometry and test set-up necessary in order to determine the compression failure mechanism of small wood block specimens reinforced With CFRP loaded in compression parallel to the grain. The method is based on an existing testing method for unreinforced wood specimens. The Digital Image Correlation (DIC) method is used to monitor deformation during experim!
15.	Azinović, Boris, et al. (författare) Glued-in rods in cross laminated timber – Numerical simulations and parametric studies 2019 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 212, s. 431-441 Tidskriftsartikel (refereegranskat)abstract Numerical simulations and parametric studies of glued-in rods in cross-laminated timber have been performed. The simulations were based on 3D finite element analysis, using a cohesive surface model for the bond-lines between the laminations and the bond-line along the rod. The parametric studies investigated the influence of the glued-in length, the rod diameter, and the rod-to-grain angle on the load-bearing capacity and stiffness of the connection. The analyses showed that the load-bearing capacity generally increases with the glued-in length and the rod diameter, which agrees well with experiments. For different rod-to-grain angles, different mechanical behaviour was observed, especially considering the failure modes.
16.	Bader, Thomas K., et al. (författare) Integrative experimental characterization and engineering modeling of single-dowel connections in LVL 2016 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 107, s. 235-246 Tidskriftsartikel (refereegranskat)abstract In order to be able to realistically and consistently elucidate and subsequently simulate the load displacement behavior of single-dowel connections, the material behavior of the individual components, namely steel dowels and wood, needs to be investigated. The behavior of slotted-in, single-dowel steel-to-laminated veneer lumber (LVL) connections with dowel diameters of 12 and 20 mm is thoroughly discussed here in relation to steel dowel and LVL properties. In addition to connection tests at different load-to-grain directions of 0, 45 and 90, the corresponding embedment behavior of LVL was tested up to dowel displacements of three times the dowel diameter. The material behavior of steel dowels was studied by means of tensile and 3-point bending tests and accompanying finite element simulations. A pronounced nonlinear behavior of the single-dowel connections was observed for all load-to-grain directions. In case of loading perpendicular to the grain, a significant hardening behavior was obvious. Due to the anisotropic material properties of wood, enforcing a loading direction of 45 to the grain resulted in an additional force perpendicular to the load direction which was quantified in a novel biaxial test setup. Thus, a comprehensive and consistent database over different scales of observations of dowel connections could be established, which subsequently was exploited by means of engineering modeling. The comparison of experimental and numerical data illustrates the potential of the engineering modeling approach to overcome drawbacks of current design regulations, which are unable to appropriately predict stiffness properties of dowel connections. Moreover, the quasi-elastic limit of dowel connections was calculated and discussed by means of the model. (c) 2016 Elsevier Ltd. All rights reserved.
17.	Bagampadde, Umaru, et al. (författare) Influence of truck load channelization on stripping in asphalt mixtures 2007 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 21:8, s. 1628-1635 Tidskriftsartikel (refereegranskat)abstract The influence of load channelization on stripping was investigated using cores and block samples from a heavily loaded highway. The original 80/100 asphalt (virgin and RTFOT aged) was characterized using conventional methods. Stripping of mixtures was measured using ASTM D1664 and that of cores using visual diametral plane rating and loss in indirect tensile strength due to soaking. The pore saturation and air voids were found to be influenced by ground water level and wheel track location across traffic lanes. Stripping was rated higher in the wheel paths than between wheel paths, especially in shallow water table areas where it was observed to be 82% higher, implying possible dependency of stripping on channelization. To enhance resistance to moisture damage, it is recommended that Hot Mix Asphalt surfaces in areas with shallow water tables be designed to a more favorable refusal density.
18.	Bedon, Chiara, et al. (författare) Performance of structural glass facades under extreme loads – Design methods, existing research, current issues and trends 2018 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 163, s. 921-937 Tidskriftsartikel (refereegranskat)abstract Glass has been overwhelmingly used for windows and facades in modern constructions, for many practical reasons, including thermal, energy, light and aesthetics. Nevertheless, due to the relatively low tensile strength and mostly brittle behaviour of glass, compared to other traditional materials, as well as to a multitude of interacting structural and non-structural components, windows/facades are one of the most fragile and vulnerable components of buildings, being representative of the physical line of separation between interior and exterior spaces. As such, multidisciplinary approaches, as well as specific fail-safe design criteria and analysis methods are required, especially under extreme loading conditions, so that casualties and injuries in the event of failure could be avoided and appropriate safety levels could be guaranteed. In this context, this paper presents a review of the state of art on analysis and design methods in use for glass facades, with careful consideration for extreme loading configurations, including natural events, such as seismic events, extreme wind or other climatic exposures, and man-made threats, i.e. blast loads and fire. Major results of available experimental outcomes, current issues and trends are also reported, summarising still open challenges.
19.	Bekele, Abiy, et al. (författare) Effect of cyclic low temperature conditioning on stiffness modulus ofasphalt concrete based on non-contact resonance testing method 2019 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 225, s. 502-509 Tidskriftsartikel (refereegranskat)abstract The stiffness modulus behaviors of three different asphalt concrete specimens that are subjected to cyclic cooling and heating are monitored. In an attempt to identify the sole effect of temperature cycles and to avoid any other biasing effects such as thermal contamination that can possibly corrupt measurements, resonance frequency measurements of the specimens are taken using an automated non-contact resonance method. The resonance frequency measurements are based on the fundamental axially symmetric mode of vibration. A hysteretic effect is observed on the measured resonance frequencies of the specimens with an application of cyclic cooling and heating. Lower stiffness moduli are obtained during the heating phase of a complete cooling and heating cycle. The stiffness moduli are calculated from measured resonance frequencies of the specimens in order to show their relative reductions due to the hysteretic effect. This finding is particularly important since it enables us to observe and understand the effect of the thermal history of asphalt concrete with regards to the reversibility behavior of its stiffness modulus. The damping of the specimens is also calculated from the measured resonance frequencies at the temperatures within the applied cyclic cooling and heating. Their observed behavior is also discussed with respect to a presence of potential micro damage.
20.	Bekele, Abiy, et al. (författare) Micro-mechanical modelling of low temperature-induced micro-damage initiation in asphalt concrete based on cohesive zone model 2021 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 286 Tidskriftsartikel (refereegranskat)abstract Asphalt pavement is subjected to cyclic temperature variations during its service life owing to changes in daily and seasonal climatic conditions. These variations tend to accumulate thermally induced distress leading to initiation and evolution of micro-cracks. The effect of cyclic thermal variations as well as ther-mal incompatibility of mastic and aggregates is of major significance for understanding the behavior of thermally induced damage in pavements. Thermal stress is developed due to differential contraction of mastic relative to aggregates in asphalt concrete at low temperatures. In this paper, low temperature micro-damage initiation in asphalt concrete due to differential thermal contraction is modelled using 2D micro-mechanical volume element. Cohesive zone model (CZM) is adopted to simulate low temper-ature damage initiation at the mastic-aggregate interface (adhesive failure) within the mixtures. A cycle of cooling and heating is applied in the micro-mechanical model in order to capture the effect of thermal damage initiation on the overall stiffness modulus of the mixtures. The results from the model reveal a reduction in stiffness modulus (as compared to the values at similar temperatures within a cycle) after the temperature of-40 degrees C is reached within the applied cyclic cooling and heating. The effects of aggre-gate gradation and binder grade are also monitored by considering four cases of mixtures formed from a combination of two different gradations and two different mastics. Results of the micro-mechanical mod-elling are also compared with experimental observations of comparable mixture types.
21.	Bekele, Abiy, et al. (författare) Micro-mechanical Modelling of Low temperature-induced micro-damageinitiation in asphalt concrete based on Cohesive zone model 2020 Ingår i: Construction and Building Materials. - 0950-0618 .- 1879-0526. Tidskriftsartikel (refereegranskat)
22.	Bjurström, Henrik, et al. (författare) Field and laboratory stress-wave measurements of asphalt concrete 2016 Ingår i: Construction and Building Materials. - : Elsevier. - 0950-0618 .- 1879-0526. ; 126, s. 508-516 Tidskriftsartikel (refereegranskat)abstract Abstract Non-contact surface wave measurements are performed on a new asphalt concrete (AC) pavement using 48 micro-electro-mechanical system (MEMS) sensors as receivers to estimate the real part of the dynamic moduli of the AC top layer. Laboratory measurements of core samples, extracted from the field measurement positions, are used to construct master curves for comparison with the field measurements. The real parts of the dynamic moduli from the two test methods are consistent at the field measurement temperatures, and the non-contact field measurements are highly repeatable. These results indicate a possible application for quality assurance of AC based on mechanical properties.
23.	Björk, Folke, et al. (författare) Properties of thermal insulation materials during extreme environment changes 2009 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 23:6, s. 2189-2195 Tidskriftsartikel (refereegranskat)abstract In this experimental study properties of condense formation, drainage and moisture dependent heat transmittance were studied for three different thermal insulation materials often used in railway carriages; glass wool (from Isover), melamine foam (Basotect) and corrugated sheets of cellulose plastics (Moniflex). The materials are quite different with respect to condense formation and maximal moisture accumulation at similar environmental conditions. They showed also considerable differences in moistures' influence on thermal transmissivity. The higher the moisture accumulation, the bigger the moistures' influence on thermal transmissivity at steady state. At a sudden reversion of the temperature field the moisture gave a temporary effect of even higher heat transmission for 1-2 h.
24.	Blyberg, Louise, et al. (författare) Glass, timber and adhesive joints - Innovative load bearing building components 2014 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 55, s. 470-478 Tidskriftsartikel (refereegranskat)abstract Structural glass-timber composite beams and shear wall elements were investigated in terms of their mechanical behaviour, energy performance and their LCA performance. The load bearing components were manufactured using annealed float glass which was adhesively bonded to the timber with different adhesives. The results show, among other things, that is is possible to join the two materials glass and timber and obtaining a non-brittle failure of the beams. The shear wall elements have the potential of being used as stabilising elements and load bearing walls in buildings of up to 4 storeys height. It is possible to combine glass and timber in a load bearing shear wall without loss of energy performance of a building or without loosing LCA performance. In addition to these benefits, the timber glass composite wall has, of course the benefit of being transparent.
25.	Brischke, Christian, et al. (författare) Modelling the outdoor performance of wood products - A review on existing approaches 2014 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 66, s. 384-397 Forskningsöversikt (refereegranskat)abstract Service life planning and performance classification are key issues in the building sector. Well-functioning 'performance models' are absolutely essential to predict the service life and functionality of buildings, building assets, and building products overtime. Different types of performance models have been established for various building materials, but cannot necessarily transferred to wood-based materials, primarily due to their organic character. For performance modelling of wood products biological agents need to be considered, such as wood disfiguring and degrading organisms. Different approaches to adequately reflect the influence of biotic and abiotic factors on the performance of wood have been reviewed and evaluated with respect to their usability in the building trade. We found that efforts in developing performance models for both fungal decay and mould growth have been intensified in recent years. A high heterogeneity among the numerous attempts became visible, different strategies have been followed, and were roughly distinguished according to the respective objectives, governing variables (e.g. mass loss, strength loss, remaining strength, decay ratings, service life, aesthetic appearance, etc.), data sources and the resulting level of accuracy. A framework of how exposure, dimension, design details, and the material-intrinsic ability to take up and release water can be linked to model the moisture risk in wood products is in principal available. Methods and models have the potential to get implemented not only in design guidelines, but also in European and international standards. In particular, various dosimeter models could serve as reliable tools to quantify the effects of different construction details. (C) 2014 Elsevier Ltd. All rights reserved.
26.	Bueno, M., et al. (författare) Low temperature characterization of bituminous binders with a new cyclic shear cooling (CSC) failure test 2014 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 58, s. 16-24 Tidskriftsartikel (refereegranskat)abstract Low temperature cracking of asphalt pavements is associated to the thermal stresses created when asphalt binder changes from a ductile into a brittle state during cooling. Under repetitive traffic loads, this change of properties can become a significant problem, resulting in the formations of large cracks on the driving surface, thus requiring early pavement repair. Nevertheless, the conventional test methods for assessing low temperature properties of bitumen are often insufficient and subject to low reproducibility. Therefore, a reliable method is necessary to characterize the performance of bituminous binders at low temperature. This work presents the cyclic shear cooling failure test (CSC-failure test) as an alternative method based on a failure test with the dynamic shear rheometer (DSR) at decreasing temperature until fracture occurs. Operational parameters, like shear strain amplitude or loading frequency, have been analysed in order to develop a reproducible procedure applicable for different types of bituminous binders. Moreover, a failure criterion has been defined by analysing the different characteristic temperatures from the failure curves obtained in the test.
27.	Bäckström, Magnus, 1967, et al. (författare) Timber-framed partition walls and their restraining effect on warp - A model for spring 2008 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 23:1, s. 71-77 Tidskriftsartikel (refereegranskat)abstract The shape of timber changes due to variations in moisture content (MC). A poor way of designing and/or erecting a structure mayresult in excessive deformation. An analytical model, which explains spring in a partition wall, is presented. The model is used for parametricstudies of various properties such as longitudinal shrinkage coefficient, modulus of elasticity and cross-sectional size of the timberstuds and stiffness of the cladding. With respect to spring, a problem is likely to occur when erecting a wall with single-sided cladding in adrying climate and the structure will benefit from relatively stiff studs and weak cladding.
28.	Bäckström, Magnus, 1967, et al. (författare) Timber-framed partition walls and their restraining effect on warp in built-in wall studs - Models for twist 2009 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 23:12, s. 3556-3563 Tidskriftsartikel (refereegranskat)abstract The shape of timber changes due to variations in moisture content (MC). Analytical models, which explain how the cladding restrains the timber studs that are prone to twist, are presented. The models are used for parametric studies of various properties. such as longitudinal shrinkage, torsional modulus of elasticity and cross-sectional size of the timber stud and stiffness of the cladding. With respect to twist, the bending stiffness of the cladding is of great importance. Large bending stiffness increases the restraint in the twist-prone studs and results in a straighter wall. Low torsional stiffness in the studs makes it easier for the cladding to restrain twist. (C) 2009 Elsevier Ltd. All rights reserved.
29.	Caprolu, Giuseppe, et al. (författare) Comparison of models and tests on bottom rails in timber frame shear walls experiencing uplift 2015 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 94, s. 148-163 Tidskriftsartikel (refereegranskat)abstract The authors present two different studies: one experimental study and one where analytical models developed to calculate the splitting failure capacity of bottom rails in partially anchored timber frame shear walls are evaluated and validated. The experimental study was divided into three parts with specimens matched to each other: (1) first the splitting capacity and failure mode of bottom rails subjected to uplift were studied; (2) then material properties such as tensile strength perpendicular to the grain; and (3) fracture energy were determined by testing specimens cut from the specimens belonging to study (1). The experimental results were compared with models based on a linear fracture mechanics approach presented earlier, using as input values results from (2) and (3). Almost all tested models show good agreement with the test results. The models showing the best agreement have been selected and proposed to be used as basis for calculation of the splitting failure capacity of bottom rails in partially anchored timber frame shear walls. (C) 2015 Elsevier Ltd. All rights reserved.
30.	Chang, Langzi, 1992, et al. (författare) 3D modelling of the interaction between bending and corrosion-induced cracks in reinforced concrete beams 2024 Ingår i: Construction and Building Materials. - 0950-0618. ; 411 Tidskriftsartikel (refereegranskat)abstract Bending and corrosion-induced cracks interact and impact the durability of Reinforced Concrete (RC) beams in a complex manner. Still, research on the mechanisms behind this interaction is limited. In this study, a 3D nonlinear finite element modelling method of RC beams was developed to explore this interactive mechanism. The models were assessed against experimental benchmarks, showing good agreement in terms of crack pattern and growth. Moreover, the modelling method offered the advantage of visualising the internal condition of beams, including the propagation of internal cracks and the expansion of corrosion products represented by interface elements. A parametric study was conducted to examine the influence of three crucial factors: the transport of the corrosion products, the distance between bending cracks, and bending crack width. The modelling results revealed that the transport of corrosion products appeared to play a decisive role in the location of initiation and evolution of corrosion-induced cracks. Additionally, as the distance between the bending cracks decreased, the onset of corrosion-induced cracks transitioned from the midpoint between the bending cracks to the vicinity of them. Furthermore, an increase in bending crack width had no impact on the initiation and evolution of corrosion-induced cracks, while their widths, and variation of width along the bar, decreased.
31.	Chen, Feng, 1987-, et al. (författare) Dynamic application of the Inductive Power Transfer (IPT) systems in an electrified road : Dielectric power loss due to pavement materials 2017 Ingår i: Construction and Building Materials. - : Elsevier. - 0950-0618 .- 1879-0526. ; 147, s. 9-16 Tidskriftsartikel (refereegranskat)abstract Inductive Power Transfer (IPT) technology is seen as a promising solution to be applied in an electrified road (eRoad) to charge Electric Vehicles (EVs) dynamically, i.e. while they are in motion. Focus in this study was placed on the dielectric loss effect of pavement surfacing materials on the inductive power transfer efficiency, induced after the integration of the technology into the physical road structure. A combined experimental and model prediction analysis was carried out to calculate this dielectric loss magnitude, based on which some preliminary conclusions as well as a prioritization of future focus needs were summarized in detail.
32.	Chen, Feng, et al. (författare) Dynamic application of the Inductive Power Transfer (IPT) systems in an electrified road : Dielectric power loss due to pavement materials 2016 Ingår i: Construction and Building Materials. - 0950-0618 .- 1879-0526. Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract It is well-known that the high cost and limited performance of existing energy storage systems have significantly constrained the commercialization of the Electric Vehicle (EV) at large scale. In recent years, attention has been given not only to the improved energy storage systems but also to develop appropriate charging infrastructures that would allow the EVs to be powered in an easier way. Inductive Power Transfer (IPT) technology, also known as a near-field wireless power transfer technology, is capable of delivering electricity wirelessly with large power and high efficiency at a given gap distance. It is therefore seen as a promising solution to be applied in an electrified road (eRoad) to charge EVs dynamically, i.e. while they are moving. Various technical aspects of this contactless charging solution have been studied actively by system developers, such as the charging power, its efficiency, the optimum gap distance as well safety issues. Focus in this study is placed on the effect of pavement surfacing materials on the wireless power transfer efficiency, after the integration of the technology into the physical road structures. Specifically, a combined experimental and model prediction analysis has been carried out to investigate this potential energy loss in a quantitative way, based on which some preliminary conclusions as well as a prioritization of future focus needs are summarized in detail. This work provides thus an important beginning for understanding the pavement materials’ influence on the IPT systems that may be used for dynamic applications in an eRoad.
33.	Chen, Y. J., et al. (författare) Resistance of concrete against combined attack of chloride and sulfate under drying-wetting cycles 2016 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 106, s. 650-658 Tidskriftsartikel (refereegranskat)abstract In this research, combined solution of chloride and sulfate was investigated for three different mixtures, including fly ash and slag. Mass change, dynamic modulus of elasticity, chloride penetration depths were tested in the different solution. Results indicated that OPC specimens showed bigger deterioration compared specimens with fly ash and slag exposed to combined solution attack under drying-wetting cycles. Additional, higher sulfate contend in combined solution retarded damage for OPC under drying-wetting cycle. Concerning the microstructure and deformation of samples, XRD-analyses is in accordance with TG/DSC-analyses, moreover, DSC/TG could quantified the results from XRD-analyses. (C) 2015 Published by Elsevier Ltd.
34.	Cwirzen, Andrzej, et al. (författare) The effect of limestone on sodium hydroxide-activated metakaolin-based geopolymers 2014 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 66, s. 53-62 Tidskriftsartikel (refereegranskat)abstract Blends of metakaolin and limestone can be alkali-activated with NaOH to form solid binders, which show relatively low strength but offer potential as a model system by which the reaction processes of more complex systems can be better understood. The effects of curing procedure, limestone content and alkalinity of the activator are able to be related to the mineralogy, mechanical properties and microstructure of hardened pastes. The presence of limestone enhances the release of Al and Si ions from metakaolin, with the Al released in the early stages of the reaction being bound into AFm-type phases. Dissolution of LS is slightly higher when a lower alkalinity sodium hydroxide activator is used. The heat treatment of pastes activated with 3 M NaOH solution resulted in a lower extent of reaction of limestone, while with 5 M solution, heat-curing at early age resulted in more reaction. The main alkali-activation product in metakaolin-limestone-NaOH pastes is a geopolymer gel with inclusions of unreacted metakaolin, limestone particles, zeolite A, and AFm phases, with different zeolites such as faujasite-like and hydrosodalite phases also identified at higher reaction temperatures. © 2014 Elsevier Ltd. All rights reserved.
35.	Damineli, Bruno L., et al. (författare) Effects of filler mineralogy on the compressive strength of cementitious mortars 2021 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 299 Tidskriftsartikel (refereegranskat)abstract Substituting cement with fillers is crucial to formulate cost-effective cementitious materials with low CO2 emissions. However, despite limestone, there is a lack of knowledge of fillers from other mineralogical sources for use in cementitious pastes. This study investigates the effects of characteristics of fillers from 6 mineralogical sources on the reactivity and compressive strength of the cementitious pastes, which could allow increasing industrial possibilities. The filler density and the paste total bound water content allowed to determine the paste porosity, which has a much better fit with the compressive strength than the water-binder ratio.
36.	Danielsson, Henrik, et al. (författare) A unified design proposal for shear stress prediction in crossing areas for cross laminated timber at in-plane shear and beam loading conditions 2022 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 355 Tidskriftsartikel (refereegranskat)abstract Environmental and urbanization challenges during the last few decades encouraged steady growth of mass timber construction where attention is drawn to cross laminated timber (CLT) as one of the most interesting products in terms of mechanical properties, versatility, efficient prefabrication and sustainability. Standardisation and codification regarding testing and design of CLT elements are hence pointed out as one of the main issues within the ongoing revision procedure of Eurocode 5. A consistent and unified design approach for CLT at pure in-plane shear loading conditions (shear walls) and at in-plane beam loading conditions is however still missing. This paper deals with analytical models for the determination of stress components related to predictions of load bearing capacity of CLT with respect to shear failure mode III – shear failure in the crossing areas constituted by the flatwise bonded areas between laminations of adjacent layers. This failure mode is relevant for both pure in-plane shear loading and in-plane beam loading conditions. The paper presents a review of previously proposed models for the prediction of shear stresses in crossing areas of CLT, for both loading conditions. Comparisons between FE-results and model predictions are reviewed indicating significant differences between them concerning the predicted influence of the CLT element lay-up and values of maximum shear stresses. Based on simplifications of models previously presented, a unified design proposal that is based on a rational and consistent mechanical background for both loading situations and that shows overall good agreement with FE-results is presented.
37.	Das, Prabir Kumar, 1982-, et al. (författare) Evaluation of the low temperature cracking performance of asphalt mixtures utilizing HMA fracture mechanics 2013 Ingår i: Construction and Building Materials. - : Elsevier. - 0950-0618 .- 1879-0526. ; 47, s. 594-600 Tidskriftsartikel (refereegranskat)abstract In the present study, the low temperature cracking performance of asphalt mixture has been investigated numerically and experimentally. To do so, the HMA thermal fracture model has extended by including fracture energy threshold and non-linear thermal contraction coefficient. This extended model is capable to predict thermally induced stress and fracture temperature, which is validated with experimental results obtained from three different types of asphalt mixtures. From the parametric study, it was observed that understanding the influence of thermal contraction coefficient, the cooling rate and the creep compliance parameters can make a significant contribution to the material's sustainability. From the analysis, it was found that this extended model can be utilized to evaluate the low temperature cracking performance of asphalt mixtures and capable to provide correct ranking. Interestingly, non-linear thermal contraction coefficient gave much better prediction than linear approach.
38.	Das, Prabir Kumar, et al. (författare) Low temperature cracking performance of WMA with the use of the Superpave indirect tensile test 2012 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 30, s. 643-649 Tidskriftsartikel (refereegranskat)abstract Low temperature cracking of wax modified bitumen and asphalt mixtures were studied using the Dynamic Shear Rheometer (DSR), Bending Beam Rheometer (BBR), Superpave IDT and Thermal Stress Restrained Specimens Test (TSRST). Two types of commercial waxes (FT-paraffin and Asphaltan-B) were added to 70/100 penetration grade bitumen. Hot Mix Asphalt (HMA) fracture mechanics was used to determine fracture parameters. Master curves obtained from DSR and BBR test results showed stiffening effect due to wax additive at low temperature. The analysis of covariance was performed using a General Linear Model (GLM) on the Superpave IDT test results for Energy Ratio (ER) by using SPSS (Statistical Program for Social Sciences). Statistical analysis of Superpave IDT results showed a minor negative effect of wax modification at lower temperatures. Statistical analysis also showed that fracture parameters are highly temperature dependent and the two types of aggregate used did not play any significant role in low temperature cracking performance. Results obtained from TSRST tests indicate wax modification has a minor negative effect in low temperature cracking performance of asphalt mixtures.
39.	de Bruijn, Paulien, et al. (författare) Moisture fixation and thermal properties of lime–hemp concrete 2013 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 47, s. 1235-1242 Tidskriftsartikel (refereegranskat)abstract Lime–hemp concrete (LHC) is a sustainable building material that combines hemp shiv and building limes. Moisture fixation and thermal properties of LHC were determined so as to gain knowledge about the material’s behaviour in a cold, wet climate. Sorption isotherms were produced over the whole moisture range for two LHC mixes by means of glass jar tests and a pressure plate apparatus. Thermal properties were determined for the mixes at different relative humidities using a transient plane source method. The results showed relatively low thermal conductivity and a steep sorption isotherm in the interval between 95% and 100% RH.
40.	Debuyser, Michael, et al. (författare) Behaviour of monolithic and laminated glass exposed to radiant heating 2017 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 130, s. 212-229 Tidskriftsartikel (refereegranskat)abstract Glass is seeing a growing interest as a structural material as a result of its relatively good strength to weight ratio and the obvious aesthetic benefits of its use in buildings. However due to the sensitivity of glass to thermal shock and the considerably temperature-dependent behaviour of interlayer materials as a result of their visco-elastic nature, the mechanical behaviour of laminated glass will be severely influenced by exposure to fire. Relatively little research has been conducted in the past to study the response of load bearing structural glass, and laminated glass in particular to radiant heating. This paper represents an effort to try to understand the effects of through depth radiation absorption and temperature conduction through laminated glass with a view to ultimately developing a model for studying load bearing glass exposed to elevated temperatures, such as those that would be expected in a fire. The paper reports on an experimental research programme in which several monolithic and laminated glass configurations were exposed to a radiant heat flux to study the different phenomena that occur upon exposure to fire conditions, including the ratios of absorbed, transmitted and reflected heat flux to the incident heat flux. The paper then presents a numerical heat transfer model which is developed based on these experimental results and that is able to determine the evolution of the temperature profile as a result of a given incident heat flux. The effectiveness of the heat transfer model is demonstrated through comparison with the temperatures measured during the experimental work.
41.	Draganovic, Almir, et al. (författare) Dispersion of microfine cement grout with ultrasound and conventional laboratory dissolvers 2020 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 251 Tidskriftsartikel (refereegranskat)abstract Grout based on microfine cement is mainly used for sealing of rock fractures in underground construction with high sealing requirements. This grout is known as hard dispersed, compared to grouts based on ordinary Portland cement. This study investigates the possibility of using ultrasound to improve the dispersion of microfine cement grout. Ultrasound dispersion is compared with dispersion efficiency of an ordinary laboratory mixer equipped with a disk, and using the rotor-stator technique. Dispersion efficiency was measured with a filter pump. The grout dispersed with the laboratory mixer and disk could not pass through a 154 mm filter. The laboratory mixer using the rotor-stator technique showed much better efficiency, with a measured dispersion that varied between 77 and 104 mm. Dispersion with ultrasound yielded more reliable results, with lower variation; the grout passed through a 77 mm filter. These results showed that a laboratory mixer with a disk is not an effective method for dispersion of microfine cement. A laboratory mixer using the rotor-stator method is much more effective. Ultrasound is not only an effective method but is even better than a mixer using the rotor-stator technique.
42.	Draganović, Almir, 1964-, et al. (författare) Filtration of silica particles from a low-pH cementitious grout 2016 Ingår i: Construction and Building Materials. - : Elsevier. - 0950-0618 .- 1879-0526. ; 105, s. 29-34 Tidskriftsartikel (refereegranskat)abstract Spent nuclear fuel is stored in rock depositories. Swelled bentonite around the stored capsules prevents eventual spread of radioactive material by ground water. The pH-value of the ground water in contact with bentonite shall be less than 11 not to affect the swelling capacity of the bentonite. Therefore cementitious grout with low pH-value is used to grout these depositories. There is a risk that pH-value of this grout can locally increase due to filtration at fracture constriction and influence pH-value of ground water. Chemical SEM EDAX-analysis indicates that there is no risk of increasing of PH-value in this grout.
43.	Draganovic, Almir, et al. (författare) Ultrasonic dispersion of hard dispersed ultrafine milled cement-based grout for water sealing of fractured hard rock 2022 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 317 Tidskriftsartikel (refereegranskat)abstract Ever higher demands on the sealing of rock around underground structures drive the development of cement based grouts. The results of the previous study demonstrated that it is possible to mill cement to approximately 20 to 25 mu m and use it to seal fracture aperture down to approximately 70 mu m. Further milling deteriorates the penetrability of the grouts due to the flocculation of the fine particles. This study investigates ultrasound as a technique to improve dispersion of grouts based on ultrafine milled cement. The grout tested is based on cement where 95% of the cement mass has particles smaller than 12 mu m and is very hard to disperse. Dispersion with ultrasound is compared with a conventional laboratory mixer equipped with a disk and rotor-stator system. The dispersion efficiency of this mixing equipment was tested by a filter pump. The results confirmed that a conventional laboratory mixer equipped with a disk is not at all suitable for dispersion of this grout. The laboratory mixer equipped with a rotor-stator system is much better than a disc but still cannot disperse this fine milled grout properly. Ultrasound was found to be the most effective method. The dispersion achieved, measured with a filter pump, was around 54 mu m which indicates that it is possible to seal fracture aperture now down to 54 mu m, which is a significant improvement.
44.	Edwards, Ylva, et al. (författare) Rheological effects of commercial waxes and polyphosphoric acid in bitumen 160/220 : High and medium temperature performance 2007 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 21:10, s. 1899-1908 Tidskriftsartikel (refereegranskat)abstract The effects of adding three commercial waxes and a polyphosphoric acid to three bitumens of 160/220 penetration grade were studied using different types of laboratory equipment, such as Dynamic Shear Rheometer (DSR), Differential Scanning Calorimeter (DSC), Force Ductilometer (FD) as well as equipment for determining conventional parameters like penetration, softening point and Fraass breaking point. The paper deals with effects at medium and high in-service temperatures likely to affect the rutting performance of an asphalt concrete pavement. The results show that magnitude and type of effect on bitumen theology depend on the bitumen as well as type and amount of additive used. Bitumen composition was found to be of decisive importance. Adding polyethylene wax or polyphosphoric acid especially to a non-waxy bitumen, showed considerable positive effects on the theological behaviour at medium and higher temperatures.
45.	Enochsson, Ola, et al. (författare) CFRP strengthened openings in two-way concrete slabs : an experimental and numerical study 2007 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 21:4, s. 810-826 Tidskriftsartikel (refereegranskat)abstract Rehabilitation and strengthening of concrete structures with externally bonded fibre reinforced polymers (FRPs) has been a viable technique for at least a decade. An interesting and useful application is strengthening of slabs or walls where openings are introduced. In these situations, FRP sheets are very suitable; not only because of their strength, but also due to that they are easy to apply in comparison to traditional steel girders or other lintel systems. Even though many benefits have been shown by strengthening openings with FRPs not much research have been presented in the literature. In this paper, laboratory tests on 11 slabs with openings, loaded with a distributed load are presented together with analytical and numerical evaluations. Six slabs with openings have been strengthened with carbon fibre reinforced polymers (CFRPs) sheets. These slabs are compared with traditionally steel reinforced slabs, both with (four slabs) and without openings (one slab). The slabs are quadratic with a side length of 2.6 m and a thickness of 100 mm. Two different sizes of openings are used, 0.85 × 0.85 m and 1.2 × 1.2 m. The results from the tests show that slabs with openings can be strengthened with externally bonded CFRP sheets. The performance is even better than for traditionally steel reinforced slabs. The numerical and analytical evaluations show good agreement with the experimental results.
46.	Escalera, Edwin, et al. (författare) The production of porous brick material from diatomaceous earth and Brazil nut shell ash 2015 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 98, s. 257-264 Tidskriftsartikel (refereegranskat)abstract Diatomaceous earth was mixed with Brazil nut shell ash (BNS ash) in different amounts between 0 and 30 wt% and sintered at temperatures between 750 and 950 °C. The BNS ash contains 33 wt% K2O and 11 wt% CaO mainly in carbonate form. The addition of BNS ash into the diatomaceous earth caused significant changes of the microstructure after sintering. The BNS ash addition produces lightweight porous bricks with acceptable strength at lower sintering temperature. The best combination of strength and porosity was achieved for a mixture of 10 wt% of BNS ash in the diatomaceous earth sintered at 850 °C. The achieved high porosity was 49%, density 1.06 g/cm3, thermal conductivity 0.20 W/(m K) and the compressive strength was 8.5 MPa.
47.	Espersson, Maria (författare) Effect in the high modulus asphalt concrete with the temperature 2014 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 71, s. 638-643 Tidskriftsartikel (refereegranskat)abstract The use of the high modulus asphalt concrete in the base course of airport pavements is not of recent utilization, but at present there is a considerable gap in the regulation for the use of this bitumen. The main objective of this paper is to present the results of the research that has been done using the experimental dynamic modulus of different mixtures of conventional bitumen with different penetration index B40/50, B60/70, B100/150, B150/200 and the high modulus bitumen B13/22 to calculate the percentage of reduction in thickness of the base course in airport pavements when is used High Modulus Asphalt Concrete (HMAC) compare with conventional bitumen mixtures and is also taken into account the temperature. In order to obtain the reduction in thickness depending on the temperature and the use of HMAC, the tests have been performed at the different temperatures -20 degrees C, -10 degrees C, 0 degrees C, 10 degrees C, 20 degrees C and all the results in this paper are presented for these temperatures. To perform the calculations of this research the Airbus A380 has been taken as Aircraft Design.
48.	Fadil, Hassan, et al. (författare) A New Viscoelastic Micromechanical Model for Bitumen-Filler Mastic 2020 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 253 Tidskriftsartikel (refereegranskat)abstract A new micromechanical model for predicting viscoelastic properties of mastic is proposed and validated with experiments. The developed model is based on the finite element method and allows predicting the viscoelastic properties of mastic by means of the fundamental mechanical and geometrical properties of its constituents. The influence of modelling parameters on the model’s accuracy is evaluated and optimal parameter combinations are identified. It is shown that the proposed model can capture the measured viscoelastic behaviour of mastics for the range of loading, temperature and material parameters examined. Accordingly, it may be a useful tool for optimizing mastics material design meeting the target viscoelastic properties.
49.	Falchi, Laura, et al. (författare) Influence and effectiveness of water-repellent admixtures on pozzolana-lime mortars for restoration application 2013 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618 .- 1879-0526. ; 49, s. 272-280 Tidskriftsartikel (refereegranskat)abstract Pozzolana-lime mortars modified with water-repellent admixtures were designed and studied to obtain mortars for restoration application. Powdered silane and calcium stearates were mixed with pozzolana, lime and sand and the chemical-physical properties of the resulting mortars were evaluated by X-ray diffraction, electron microscopy (SEM-EDX), thermogravimetric analysis and FT-IR spectroscopy. The mechanical behavior, the pore structure and the hygric behavior were measured. The resistance of water-repellent mortars to the salt crystallization was evaluated. Both calcium stearates and powdered silane allowed good water-repellent protection even if the water-repellent agents and their dosage modified some physical properties and the hydration kinetic.
50.	Fan, Xu, et al. (författare) Effects of different supplementary cementitious materials on the performance and environment of eco-friendly mortar prepared from waste incineration bottom ash 2022 Ingår i: Construction and Building Materials. - : Elsevier BV. - 0950-0618. ; 356 Tidskriftsartikel (refereegranskat)abstract Municipal solid waste incineration bottom ash (MSWIBA) is a by-product produced by municipal waste incineration treatment. In this study, MSWIBA particle size distribution, chemical composition and particle shape were investigated and confirmed its value for reuse in the construction field and its good research potential. MSWIBA was used as fine aggregates, while coal fly ash (FA) and ground granulated blast furnace slag (GGBFS) were used as auxiliary cementitious materials to replace part of cement to manufacture the eco-friendly mortar (EFM). The effect of FA/GGBFS on the mechanical and microscopic properties of EFM with different material ratios was mainly investigated. And the analysis of the environmental friendliness and economy of this EFM was made. The results show that the combination of FA and GGBFS at the same time reduces the early mechanical properties of the mortar. However, the strength developed rapidly after 7 days, with an increase of more than 6 times the rate before 7 days. Compared with GGBFS, FA is more helpful in improving the mechanical properties of the EFM. After 28 days of full hydration, the hydration products within the EFM are numerous and well bonded to each other. Not only do these hydration products increase the mechanical strength of EFM, but they also successfully solidify the hazardous components in MSWIBA and reduce their negative environmental effects. In addition, the use of MSWIBA instead of sand for mortar preparation reduces energy consumption and CO2 emissions, and it reduces the cost by more than 50 %. This indicates that MSWIBA may perform well in the future development of the civil infrastructures. As well as recycling waste resources, it makes a valuable contribution to the development of green and sustainable building materials.

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