| 1. |
- Badanoiu, Alina, et al.
(författare)
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Cementitious composites reinforced with continuous carbon fibres for strengthening of concrete structures
- 2003
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Ingår i: Cement & Concrete Composites. - 0958-9465 .- 1873-393X. ; 25:3, s. 387-394
-
Tidskriftsartikel (refereegranskat)abstract
- Continuous fibre wrapping technique is becoming a common repair and strengthening technique for concrete structures. In this method continuous fibre sheets are bonded to the surface of a concrete structure using organic resins. The main disadvantages of this method are: (i) the use of resins (organic compounds) which are hazardous for the manual worker, and (ii) the low permeability of this type of organic materials. These problems could be solved if a cement-based matrix is used instead of epoxy matrix. In the current development stage one of the limiting parameter in a cementitious carbon fibre composite is the bond between the fibres and the cementitious matrix. The main objective of the study presented in this paper was to improve the bond between the carbon fibres and the cementitious matrix. Two possible methods were studied: (i) the design of a complex binder based on Portland cement with polymer and silica fume additions and (ii) surface treatment of the carbon fibres prior to their casting in the cementitious composite.
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| 2. |
- Buasiri, Thanyarat, et al.
(författare)
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Sensing mechanisms of nanomodified Portland cement composites
- 2024
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Ingår i: Cement & Concrete Composites. - : Elsevier. - 0958-9465 .- 1873-393X. ; 151
-
Tidskriftsartikel (refereegranskat)abstract
- Mortar sensors were fabricated as beams incorporating different amounts of carbon nanofibers (CNFs) synthesized in-situ on cement particles. Changes in electrical resistivity were measured and compared to recorded changes in compressive stress, temperature, and humidity. Sensing mechanisms and corresponding models were developed. The findings of the study indicate that the piezoresistive effect is influenced by the critical concentration of CNFs inside the composite matrix and the tunneling effect. In addition, water absorption and desorption, as well as the amount of chemically bound water played an important role in humidity sensing. Thermal fluctuation-induced tunneling conduction was dominant for the temperature sensitivity.
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| 3. |
- Falchi, Laura, et al.
(författare)
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The influence of water-repellent admixtures on the behaviour and the effectiveness of Portland limestone cement mortars
- 2015
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Ingår i: Cement & Concrete Composites. - : Elsevier. - 0958-9465 .- 1873-393X. ; 59, s. 107-118
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Tidskriftsartikel (refereegranskat)abstract
- Abstract Water-repellent mortars were prepared using different hydrophobic compounds as admixtures. Calcium and zinc stearates, silane/siloxane products (as liquid solution and powder) were mixed into limestone cement mortars for obtaining in-bulk water-repellent mortars suitable for building protection and resistant to the degrading action of water. The influences of the admixtures on the hydration and structure of the designed mortars were investigated by SEM, TG–DSC, FT-IR, XRD, and isothermal calorimetry. The effectiveness of these agents against water action was evaluated by using techniques and methods such as mercury intrusion porosimetry, water absorption tests and contact angle measurements. Siloxane products conveyed good water-repellent effectiveness, without strongly influencing the setting and hydration of the binder, while the zinc stearates slowed down the hydration reactions.
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| 4. |
- Hallgren, Mikael, et al.
(författare)
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Non-linear finite element analyses of punching shear failure of column footings
- 2002
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Ingår i: Cement & Concrete Composites. - 0958-9465 .- 1873-393X. ; 24:6, s. 491-496
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Tidskriftsartikel (refereegranskat)abstract
- Current design methods and code formulas for the assessment of the punching shear strength are normally based on tests on slabs with relatively high slenderness, i.e., with high shear-span to depth ratios. Column footings normally have low shear-span to depth ratios. Previous punching tests on column footings indicate that the failure mechanism for punching of slabs with low shear-span to depth ratios differs from that of slabs with high shear-span to depth ratios. In this investigation, punching tests on two circular column footings of reinforced concrete were simulated numerically. The results show how the failure mechanism differs from that of more slender slabs. A parametric study also confirms that the punching shear strength of the analysed slabs strongly depends on the compressive strength of concrete.
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| 5. |
- Johannesson, Björn
(författare)
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Dimensional and ice content changes of hardened concrete at different freezing and thawing temperatures
- 2010
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Ingår i: Cement & Concrete Composites. - : Elsevier BV. - 0958-9465 .- 1873-393X. ; 32:1, s. 73-83
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Tidskriftsartikel (refereegranskat)abstract
- Samples of concrete at different water-to-cement ratios and air contents subjected to freeze/thaw cycles with the lowest temperature at about -80 degrees C are investigated. By adopting a novel technique, a scanning calorimeter is used to obtain data from which the ice contents at different freeze temperatures can be calculated. The length change caused by temperature and ice content changes during test is measured by a separate experiment using the same types of freeze-thaw cycles as in the calorimetric tests. In this way it was possible to compare the amount of formed ice at different temperatures and the corresponding measured length changes. The development of cracks in the material structure was indicated by an ultra-sonic technique by measuring on the samples before and after the freeze-thaw tests. Further the air void structure was investigated using a microscopic technique in which air'bubble' size distributions and the so-called spacing factor, indicating the mean distance between air bubbles, were measured. By analyzing the experimental result, it is concluded that damages occur in the temperature range of about -10 degrees C to -55 degrees C, when the air content is lower than about 4% of the total volume. For a totally water-saturated concrete, damages always occur independently of the use of entrained air or low water-to-cement ratios. It is, further, concluded that the length changes of these samples correspond to the Calculated ice contents at different temperatures in a linear fashion. @ 2009 Elsevier Ltd. All rights reserved.
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| 6. |
- John, Vanderley, et al.
(författare)
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Durability of slag mortar reinforced with coconut fibre
- 2005
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Ingår i: Cement & Concrete Composites. - : Elsevier BV. - 0958-9465 .- 1873-393X. ; 27:5, s. 565-574
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Tidskriftsartikel (refereegranskat)abstract
- A comparative study of the microstructure of both new and in-use aged blast-furnace slag cement coir reinforced composite was performed. Aged samples came from internal and external walls of a 12-year-old house, built in Sao Paulo. The panels of the house were produced using 1:1.5:0.504 (binder: sand: water, by mass) mortar reinforced with 2% of coir fibre by Volume. The binder was blast-furnace slag activated by 2% of lime and 10% of gypsum. Fibres were removed from the composite and Subsequently cleaned with acid solution (chloridric acid, 10%) in an ultrasonic bath. Both aged and new fibres were studied under low pressure BSE SEM with EDS analysis. The lignin content of the fibre was measured by the acetyl bromide method and qualitatively evaluated by Weisner reaction using an optical microscope. Cement transformations were Studied by X-ray diffraction and TG. Its pore water composition was also determined. Carbonation was measured by phenolphthalein. Composites were Studied under low vacuum SEM. Interfaces and deposition of inorganic species in the fibre lumen were also investigated. Methods are described. After 12 years, the cement was fully carbonated. Fibres removed from the old samples seem to be undamaged when examined under SEM. Qualitative lignin content determination by Wiesner reaction suggests that old samples have lower content of guaiacyl lignin units. Nevertheless. the total lignin content of old fibres when measured by using the acetyl bromide method, is comparable to that reported in literature. No significant difference was found in the lignin content of fibres removed from external and those removed from internal wails.
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| 7. |
- Justnes, Harald, et al.
(författare)
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Microstructure and performance of energetically modified cement (EMC) with high filler content
- 2007
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Ingår i: Cement & Concrete Composites. - : Elsevier BV. - 0958-9465 .- 1873-393X. ; 29:7, s. 533-541
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Tidskriftsartikel (refereegranskat)abstract
- Energetically modified cement (EMC) has been produced by high intensive grinding/activation of normal portland caemnet (NPC) together with 20% and 50% quartz sand. EMC concretes were compared to NPC based concrete using the k-factor concept. The k-factor for concrete with w/c = 0.60 - 0.45 was 0.7 - 0.9 for 1 day and 1.1 - 1.3 for 28 days compressive strength. k > 1 for both capillay suction, porosity, vapor diffusion and chloride permeability. For carboantion resistance k was approximately 0.55.Microstructure of EMC paste with 50 % quartz sand and w/c = 0.40 showed that the quartz was extensively ground and formed agglomerates with concrete having a high inner surface. The degree of hydration of the cement in EMC was as high as 71 % after 1 day comparted to 45 % for untreated blend. Refind pore sizr distribution of EMC versus blend means that even for equal hydration at higher ages EMC will perform better.
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| 8. |
- Schlegel, Moritz Caspar, et al.
(författare)
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Spatially resolved investigation of complex multi-phase systems using μxRF, SEM-EDX and high resolution SyXRD
- 2013
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Ingår i: Cement & Concrete Composites. - : Elsevier BV. - 0958-9465 .- 1873-393X. ; 37:1, s. 241-245
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Tidskriftsartikel (refereegranskat)abstract
- Spatially resolved analysis of complex multi-phase systems can be validated through different analytical methods. This study compares investigations by scanning electron microscopy coupled with energy dispersive X-ray fluorescence analysis and high resolution X-ray diffraction. The studied sulfate attacked cement paste containing fly ashes consists of different interacting crystalline and amorphous phases. The complementary methods revealed in detail changes in phase composition due to the chemical attack. The advantages and disadvantages of both methods are discussed and suggestions are given for combining them with additional methods to maximize the information content.
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| 9. |
- Srivastava, Sumit, et al.
(författare)
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Carbonated steel slags as supplementary cementitious materials : Reaction kinetics and phase evolution
- 2023
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Ingår i: Cement & Concrete Composites. - : Elsevier Ltd. - 0958-9465 .- 1873-393X. ; 142
-
Tidskriftsartikel (refereegranskat)abstract
- With increasing interest in utilizing metallurgical slags for mineral carbonation, there is a need to find applications for carbonated slags. The scope of this study is to explore the utilization potential of carbonated steel furnace slags (SFS) as supplementary cementitious materials (SCM) to produce low-CO2 cement-based materials. Two different types of SFS are studied with comparable amounts of major oxides but significantly different mineral phase compositions. In the first phase of the study, several parameters that affect the CO2 uptake during mineral carbonation are considered (temperature, CO2 pressure, particle size, and duration) for the two slags namely, basic oxygen furnace slag (BOFS) and desulfurized slag (DeSS). Among the two slags, the DeSS exhibited significantly higher degrees of carbonation than BOFS, and the higher carbonation of DeSS is attributed to the presence of Ca as Ca(OH)2 rather than Ca–Si in BOFS. For both the slags, increase in temperature and CO2 pressure generally led to increase in the degree of carbonation. In the second phase of the study, 30 wt% of white Portland cement (WPC) was replaced by carbonated slags (used as SCM) in the cement mixture. The cement mixture with the BOFS carbonated at 60 °C and 1 bar CO2 pressure, as SCM, exhibited compressive strength comparable with that of WPC. Higher degrees and rates of carbonation under different conditions appears to have reduced their reactivities as SCM. © 2023 The Author(s)
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| 10. |
- Taheri, Hesam, et al.
(författare)
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Selection of suitable cellulose nanofibers derived from eco-friendly sources for the production of lightweight cementitious composites with tuned rheological, mechanical, and microstructure properties
- 2024
-
Ingår i: Cement & Concrete Composites. - : Elsevier BV. - 0958-9465 .- 1873-393X. ; 151
-
Tidskriftsartikel (refereegranskat)abstract
- Different cellulose nanofibers (CNF) and ordinary Portland cement (OPC) were combined to prepare CNF-OPC composite pastes at different water to cement ratios (W/C) to optimize density, thermal conductivity, and mechanical strength. The rheological data of CNF-OPC composites showed that the viscosity and yield stress of the mixtures were abruptly increased in comparison to those of OPC pastes at equal W/C. Rheological and morphological data showed that the uniformity of the CNF and degree of fiber entanglement plays a significant role in tuning the composite properties. CNF suspensions with short fibers were observed to improve the mechanical properties of the composite while suspensions with entangled fiber networks were found to decrease density and thermal conductivity. Loss of flexural strength of CNF-OPC compared to OPC was found to be to a lesser extent than loss of compressive strength. The dry density and thermal conductivity of the CNF-OPC composites were substantially reduced to the range of 750 (kg/m(3)) and 0.1 (W/m(-1)K(-1)) at W/C = 2. CNF caused a reduction in peak temperature and postponed the hydration peak by more than 2 h compared to OPC.
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| 11. |
- Westerholm, Mikael, et al.
(författare)
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Influence of fine aggregate characteristics on the rheological properties of mortars
- 2008
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Ingår i: Cement & Concrete Composites. - : Elsevier BV. - 0958-9465 .- 1873-393X. ; 30:4, s. 274-282
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents results from a laboratory study on the influence of crushed fine aggregate on the rheological properties, i.e., yield stress and plastic viscosity, of the mortar phase of concrete. The effect of grading, particle shape, etc. of the fine aggregates has been evaluated with the use of a viscometer suited for coarse particle suspensions. The evaluation has been done at different dosages of super-plasticizer and paste volumes by the use of an inert artificial "cement paste". The results show that the properties and amount of fine aggregate have a strong influence on the water demand and workability of the mortar, i.e., the rheology. The large amounts of fines often found in crushed fine aggregate primarily increases the yield stress of the mortar. The amount of fines also contributes to the plastic viscosity by increased interparticle friction. However, the results clearly show that the particle shape of the fine aggregate strongly contributes to the plastic viscosity. The influence of the properties of the fine aggregate is largely dependent on the paste volume of the mortar. Thus, by increasing the paste volume, negative effects of poorly graded and shaped aggregates can be eliminated or significantly reduced.
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| 12. |
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| 13. |
- Bado, Mattia Francesco, et al.
(författare)
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Characterization of concrete shrinkage induced strains in internally-restrained RC structures by distributed optical fiber sensing
- 2021
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Ingår i: Cement and Concrete Composites. - : Elsevier BV. - 0958-9465. ; 120
-
Tidskriftsartikel (refereegranskat)abstract
- The present paper reports the result of an inter-university experimental investigation on concrete shrinkage induced strains on embedded rebars instrumented with Distributed Optical Fiber Sensors (DOFS). The monitoring was performed for a standard 28 days drying time and for a shorter 6 days time span (reflecting realistic constructions schedules accelerations to meet set deadlines). The tested specimens were Reinforced Concrete (RC) tensile members differing in their geometry, DOFS employed and fiber/rebar bonding techniques. Regarding the latter, a combination of cyanoacrylate (for gluing) and silicone (protection) was found to be the optimal one for deployments inside RC structures. The DOFS-reported combined effect of concrete shrinkage and creep on the embedded rebars is compared with the Model Code 2010's predictions and employed to extract conclusions on the residual performance of the RC members at the end of their drying phase.
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| 14. |
- Berrocal, Carlos Gil, 1986, et al.
(författare)
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Electrical resistivity measurements in steel fibre reinforced cementitious materials
- 2018
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Ingår i: Cement and Concrete Composites. - : Elsevier BV. - 0958-9465. ; 89, s. 216-229
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Tidskriftsartikel (refereegranskat)abstract
- This paper reports results from experiments aimed at better understanding the influence of fibre dosage and fibre geometry on the AC frequency needed to determine the DC resistivity of cementitious materials containing steel fibres. Impedance spectroscopy and DC galvanodynamic measurements were performed on mortar prisms with varying fibre reinforcement to determine the matrix resistivity (related to ionic current within the pore solution) and composite resistivity (accounting for both ionic current and electronic current through the fibres). The results showed that adding steel fibres did not significantly affect the DC nor the AC matrix resistivity of the mortar prisms. However, the steel fibres yielded a drastic reduction of the frequency associated to the AC matrix resistivity from ∼1 kHz in plain mortar to ∼1 Hz in steel fibre reinforced mortar. These findings revealed the need to adequately adjust the frequency in AC resistivity measurements of steel fibre reinforced cementitious materials.
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| 15. |
- Cui, Hongzhi, et al.
(författare)
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Possible pitfall in sample preparation for SEM analysis - A discussion of the paper “Fabrication of polycarboxylate/graphene oxide nanosheet composites by copolymerization for reinforcing and toughening cement composites” by Lv et al.
- 2017
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Ingår i: Cement and Concrete Composites. - : Elsevier BV. - 0958-9465. ; 77, s. 81-85
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a discussion of the paper published by Lv et al. in Cement and Concrete Composites, 2016, 66: 1–9. The discussion is mainly focused on whether or not graphene oxide (GO) nanosheets can regulate formation of flower-like cement hydration crystals. Lv et al. in their paper proposed a regulation mechanism stating that GO nanosheets can control ettringite (AFt), monosulfate (AFm) and calcium hydroxide (CH) to form the flower-like and polyhedron crystals, whilst our experimental results show that there might be a possible pitfall in sample preparation for SEM analysis. It is here suggested that the main chemical components of flower-like and polyhedron crystals are calcium carbonates, which are not the products from cement hydration but from carbonation of cementitious hydrates. It is therefore suggested that further study is needed to verify the regulation mechanism of GO on cement hydration crystals proposed by Lv et al. in the discussed paper.
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| 16. |
- Hong, Shuxian, et al.
(författare)
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Determination of impressed current efficiency during accelerated corrosion of reinforcement
- 2020
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Ingår i: Cement and Concrete Composites. - : Elsevier BV. - 0958-9465. ; 108
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Tidskriftsartikel (refereegranskat)abstract
- Impressed current technique is a widely adopted method for accelerating corrosion of steel reinforcement. The mass loss of steel can be theoretically estimated by Faraday's law with the assumption that all of the impressed current participated in the corrosion reaction. In the present study, accelerated corrosion process of reinforcing steel with impressed current was non-destructively traced by X-ray micro-computed tomography (μCT) with high accuracy. The mass loss of steel at different accelerated corrosion periods was analyzed and the efficiency of impressed current was calculated. It was found that the mass loss of steel did not always follow Faraday's law, and impressed current efficiencies varied with different corrosion periods. In the early corrosion periods, the water electrolysis occurred and lowered the current efficiency due to the high anode potential. While in the late corrosion periods, the natural corrosion caused the current efficiency to exceed 100%.
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| 17. |
- Huang, Liming, 1993, et al.
(författare)
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Real-time monitoring the electrical properties of pastes to map the hydration induced microstructure change in cement-based materials
- 2022
-
Ingår i: Cement and Concrete Composites. - : Elsevier BV. - 0958-9465. ; 132
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Tidskriftsartikel (refereegranskat)abstract
- The effect of the supplementary materials (SCMs) on the moisture content and ion diffusivity at different hydration time is important for the service life modelling of modern concrete. This study designed a simple but valid method to monitor the microstructure change in pastes during hydration. A procedure easy to implement was proposed to detect the water content in pastes. The electrical conductivity of pore solution was evaluated by the evaporable water content in pastes and chemical composition in the binders. Results show that the electrical properties of pastes (conductivity, formation factor and its growth rate) can effectively indicate the hydration reactivity of binder, pore connectivity and volume of pore solution in the hardened pastes. The effect of waterbinder ratio and SCMs on the structure of pastes are effectively indexed by the formation factor which is the conductivity of pore solution divided by that of paste. The inflection point of average growth rate of formation factor is a good index for the final setting of pastes. The relation between volume of evaporable water and formation factor is well demonstrated by the extended percolation theory. The real-time monitored electrical conductivity and formation factor of pastes can be used to calculate the chloride migration coefficient in hardened cement pastes.
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| 18. |
- Lindvall, Anders, 1971
(författare)
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Chloride ingress data from field and laboratory exposure - Influence of salinity and temperature
- 2007
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Ingår i: Cement and Concrete Composites. - : Elsevier BV. - 0958-9465. ; 29:2, s. 88-93
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Tidskriftsartikel (refereegranskat)abstract
- Marine exposure conditions provide an aggressive environment for reinforced concrete structures, mainly due to the occurrence of chloride-induced reinforcement corrosion. There are several influencing factors, but despite a lot of research little is known about the influence from variations in the exposure conditions. Therefore an exposure programme has been made, where concrete specimens, made from one single concrete composition, have been exposed at 12 marine locations around the world, along with a parallel study under laboratory conditions. The specimens have been constantly submerged during the exposure to get well-defined exposure conditions. The purpose was to get a quantitative measure of how different exposure conditions influence the durability of reinforced concrete, measured in terms of chloride ingress into the concrete. The results indicate that the exposure conditions (salinity and temperature of seawater), as expected, influenced the chloride ingress. This is further analysed and discussed in the paper. (c) 2006 Elsevier Ltd. All rights reserved.
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| 19. |
- Liu, Jun, et al.
(författare)
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Determining the influence of LC2 and FA on the iodide diffusion coefficient of in seawater and sea sand concrete: A novel modified RIM test method
- 2023
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Ingår i: Cement and Concrete Composites. - 0958-9465. ; 143
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Tidskriftsartikel (refereegranskat)abstract
- A novel modified Rapid Iodide Migration (RIM) test method was used to determine the influence of LC2 and FA on iodide ion diffusion coefficient of seawater and sea sand concrete (SSC). A 0.1 mol/L AgNO3 solution was selected as the indicator to develop the colour of iodide in SSC, and a lowered mass fraction of NaI solution was selected to improve the RIM test. An X-Ray Fluorescence (XRF) test was employed to detect the feasibility of the modified RIM test. Additionally, the effects of the w/c ratio, the type and substitution rate of supplementary cementitious materials (SCMs), and the compressive strength on the iodide ion diffusion coefficient of SSC were studied using the modified RIM test. The results show that it is completely feasible to use AgNO3 solution as an indicator. A lower mass fraction of NaI solution not only does not change the iodide ion diffusion coefficient of concrete but also reduces the test cost by 77.46% when using a 5 wt% NaI solution. Moreover, using SCMs to replace cement, liking fly ash (FA) and calcined clay and limestone (LC2), significantly reduces the iodide ion permeability of SSC, especially the use of LC2. Furthermore, there is a nonlinear relationship between the compressive strength and the iodide ion diffusion coefficient of SSC. This work is beneficial for the promotion of the application of modified RIM tests in studies of concrete contaminated with chloride and can provide a theoretical basis for the application of seawater and sea sand in engineering practices.
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| 20. |
- Olsson, Nilla, et al.
(författare)
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Non-Saturated Ion Diffusion In Concrete–A New Approach To Evaluate Conductivity Measurements
- 2013
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Ingår i: Cement & Concrete Composites. - : Elsevier BV. - 0958-9465. ; 40, s. 40-47
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Tidskriftsartikel (refereegranskat)abstract
- Non-saturated ion diffusion properties of cementitious materials were evaluated in an experimental study. To assess these properties, resistivity measurements have been performed on mortars with different binders (ordinary Portland cement – OPC, OPC with 5% silica fume, 40% slag and 70% slag, respectively) and different water-to-binder ratios (w/b, 0.38 and 0.53). Specimens have been conditioned to eight different climates with relative humidity (RH) from 100% to 33% RH in order to assess an effective diffusion coefficient. The results from the resistivity measurements have been corrected for changes of the conductivity of the pore solution when drying to different degrees of saturation. The diffusion coefficients for Portland cement binders within the range 100–59% RH are presented.They showed that the diffusion coefficient of the mortar with high w/b ratio was higher at high RH,but at low RH the opposite trend was found. By comparing these results with the corresponding desorption isotherms, it is shown that the diffusion coefficient for the two w/b ratios have the same dependency on the degree of saturation.
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| 21. |
- Oxfall, Mikael, et al.
(författare)
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Long-term hygrothermal performance of nuclear reactor concrete containments - Laboratory evaluations of measurement setup, in situ sampling, and moisture flux calculations
- 2016
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Ingår i: Cement & Concrete Composites. - : Elsevier BV. - 0958-9465. ; 65, s. 128-138
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Tidskriftsartikel (refereegranskat)abstract
- A measurement setup for in situ sampling of internal relative humidity and temperature in concrete structures was developed. The setup was used to evaluate the moisture conditions and to determine whether drying of the concrete components within a nuclear reactor containment contributes to the moisture conditions. The measurement setup was tested for accuracy and thereafter installed in Swedish nuclear reactor containments for in situ monitoring. Results from the measurements confirmed that the setup is suitable, especially for long-term measurements at depths of 50 mm or more. Complementary moisture transport calculations showed that the moisture flux from the concrete to the interior of the reactor containment have a noticeable effect on the environmental conditions in the containments. The calculations of the moisture condition in the concrete show that 15-30% of the evaporable water in the concrete has been dried out during the 30 years of operation. (C) 2015 Elsevier Ltd. All rights reserved.
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| 22. |
- Sciegaj, A., et al.
(författare)
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Experiments and calibration of a bond-slip relation and efficiency factors for textile reinforcement in concrete
- 2022
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Ingår i: Cement and Concrete Composites. - : Elsevier BV. - 0958-9465. ; 134
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Tidskriftsartikel (refereegranskat)abstract
- Textile reinforcement yarns consist of many filaments, which can slip relative each other. At modelling of the global structural behaviour, interfilament slip in the yarns, and slip between the yarns and the concrete can be considered by efficiency factors for the stiffness and strength of the yarns, and by applying a bond-slip relation between yarns and concrete. In this work, an effective and robust method for calibration of such models was developed. Two-sided asymmetrical pull-out tests were carried out, with varying embedment lengths designed to obtain both pull-out and rupture of the textile as failure mode. The efficiency factors for strength and stiffness of the textile were very similar, 34% and 35% respectively. This indicates the stress distribution within a yarn to be uneven in a similar manner for small and large stress levels, and that interfilament slip has a larger influence than variation of filaments’ strength.
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