| 1. |
- Al-Gburi, Majid, et al.
(författare)
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Reducing Thermal Crack Risks Caused by Restraint in Young Concrete - A Case Study on Walls of Water Tanks
- 2022
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter. - 0800-6377 .- 2545-2819. ; 66:1, s. 41-54
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Tidskriftsartikel (refereegranskat)abstract
- Concrete cracks in structures such as water tanks and nuclear power stations cause anxiety to owners, contractors and engineers. These cracks may significantly increase the structure’s permeability and thus increase leakage, reduce durability, and eventually lead to loss of structural functionality. Therefore it is important to minimize their occurrence and size. To identify effective ways of minimizing cracking in young concrete segments, a parametric study was conducted using the finite element method (FEM). Parameters considered include casting sequence, joint position, wall height, and cooling. The study examined continuous and jumped casting approaches to the casting of a cylindrical reinforced concrete tank for a sewage-treatment plant, with and without the application of the ‘kicker’ technique in which the lower part of the wall is cast with the slab. The main cause of cracking is thermal change and restraint imposed by adjacent older structures, and the FEM predictions agree well with experimental observations. Continuous casting is most effective at minimizing cracking because it creates only two contact edges between newly cast and existing structures producing the lowest level of restraint. The kicker technique is shown to be very effective for reducing restraint and consider rephasing.
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| 2. |
- Andersson, Louise, et al.
(författare)
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Effect of High-Pressure Washing on Chloride Ingress in Concrete : Development of an Accelerated Test Method
- 2022
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 67:2, s. 35-50
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Tidskriftsartikel (refereegranskat)abstract
- Bridges constitute an important part of the infrastructure. For bridges to have the longest possible service life with minimum repairs, the maintenance is of great importance. One type of bridge maintenance that is rarely researched is the continuous preventive maintenance. The continuous preventive maintenance consists of removal of vegetation, cleaning of bridge joints and drainage systems as well as high-pressure washing of the structure. The effect of washing is discussed but not properly researched. A study on the effectiveness of high-pressure washing on concrete is therefore being conducted. An accelerated test method is being developed to mimic field testing. The method has been developed through tests on small concrete specimens subjected to fluctuating temperature, fluctuating moisture, and repeatable exposure to de-icing salt during several cycles. The specimens are of two recipes where one represents an old concrete bridge with rather high water-cement ratio (0.6) and the other one represents a new concrete bridge with a low water-cement ratio (0.4). The first two versions of the method are described. The second version shows promising results, but the method needs further development to incorporate additional factors.
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| 3. |
- Baba Ahmadi, Arezou, 1985, et al.
(författare)
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Utilization of Bio Ashes in Cement-based Materials: A Case Study in Cooperation with Pulp and Paper and Energy Production Industries in Sweden
- 2020
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 63:2, s. 63-78
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Tidskriftsartikel (refereegranskat)abstract
- Worldwide increased concern of the CO2 emissions has led to the replacement of coal by biomass in combustion-based power plants. However, this would cause the scarcity of fly ash, one of the most well-known rest products from coal combustion, which is used as supplementary cementitious materials (SCM) in construction sector to reduce the large environmental footprint of cement production. Seeking to find alternative SCMs, this article aims to demonstrate the viability of using bio ashes in Sweden as SCM, which, due to lack of studies validating their value, are landfilled today. According to the obtained results, bio ashes produced at pulp and paper industries have a considerably consistent chemical composition and exhibit a satisfactory pozzolanic behaviour. Nevertheless, according to the conclusions of this study, the pozzolanicity of these alternative binders is not reflected equally with respect to the most known reactivity tests for common SCMs. The results imply that although “R3” tests method infers the pozzolanic characteristics of the bio ashes in focus of this study, the “activity index test” as well as “calcium consumption test” indicate otherwise.
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| 4. |
- Gram, Annika, et al.
(författare)
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Evaluation of Crushed Fine Materials
- 2022
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 67:2, s. 65-77
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Tidskriftsartikel (refereegranskat)abstract
- As natural resources of sand and fine material used in the concrete industry are becoming more scarce, crushed materials are being used to a greater extent. Shape and texture of machine crushed materials differ from aggregates naturally ground, layered and sorted under the course of millions of years. It is assumed that crushed aggregates are more angular and of less smooth texture than natural aggregates, which will affect the flow behaviour of a suspension containing crushed material. In the mix design process of cementitous suspensions, an adequate rheology of the micro mortar (all constituents in the concrete being able to pass a 0.125 mm sieve, including the cement) is crucial. In this paper, the shape of fine particles is linked to the micro mortar plastic viscosity of the filler suspension including cement. The plastic viscosity here serves as an important quality assessment of the filler, since the micro mortar workability features are vital for the final mix design quality of the concrete workability.
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| 5. |
- Hasholt, Marianne Tange, et al.
(författare)
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Nordic Concrete Research workshop : "Accelerated freeze-thaw testing of concrete", Lyngby, 20th April 2022
- 2022
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Ingår i: Nordic Concrete Research. - : SCIENDO. - 0800-6377 .- 2545-2819. ; 66:1, s. 113-133
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Tidskriftsartikel (refereegranskat)abstract
- A one-day Nordic Concrete Research workshop on "Accelerated freeze-thaw testing of concrete" attracted approx. 30 participants. The workshop included presentations on various aspects, such as observed frost damage in the field and the importance of the temperature curve during testing as well as other interactions with the surroundings of the concrete. The workshop also included examples of recent research, which can improve our knowledge about the frost damage mechanism and therefore provide input to improving the standardised test methods. The present paper is a summary of the nine presentations and the discussion arising from the presentations.
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| 6. |
- Hernández Vargas, Jose, et al.
(författare)
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Grading Material Properties in 3D Printed Concrete Structures
- 2022
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 66:1, s. 73-89
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Tidskriftsartikel (refereegranskat)abstract
- Functionally graded materials (FGMs) describe composite materials with a gradual change in properties along one or several axes. A major advantage with this approach is the avoidance of discontinuities between different layers of material. 3D Printing offers the possibility to control the material composition and spatial placement along the printing process to create structures with graded properties. However, there are very few examples of the application of this approach to 3D concrete printing (3DCP). This paper presents a review of the current approaches of and methods to grade the material properties of a 3DCP structure, as well as a review of similar methods used in other 3D printing processes. Finally, the potential applicability of these principles into concrete are presented and discussed.
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| 7. |
- Lindh, Per, et al.
(författare)
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Resonant Frequency Ultrasonic P-Waves for Evaluating Uniaxial Compressive Strength of the Stabilized Slag–Cement Sediments
- 2021
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 65:2/2021, s. 39-62
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Tidskriftsartikel (refereegranskat)abstract
- Marina sediment kan stabiliseras med ultrahöghållfasta bindemedel: cement, Cement Kiln Dust (CKD) och slagg. Egenskaperna hos den stabiliserade jorden indikerar potential för återanvändning. Den här studien undersökte prestandan för den enaxiella tryckhållfastheten (UCS) i smarina sediment stabiliserade med bindemedel (cement, CKD, slagg), testade med ultraljuds P-vågor. Material omfattar 194 prover insamlade från Göteborgs hamn. Experimentet utfördes av Sveriges Geotekniska Institutet (SGI). Tryckhållfastheten hos prover stabiliseras med olika förhållande av bindemedel (cement, CKD, slagg) testades med resonansfrekvenser (P-vågor). Korrelationsprofilerna för lågt vatten/hög bindemedel (LW/HB) cement/slagg (40/60 %) kontrollerades genom härdningstid. Simplextesten för slagg-cement-CKD visade UCS av prover med låg/hög vattenhalt och olika bindemedelsförhållande av cement (kg/m3). Förhållandet mellan cementbindemedel och härdningstid spelar en avgörande roll för ökningen av UCS följt av mekaniska egenskaper hos prover och spänningsintensitet. De högsta värdena 1000 m/s i P-vågor. Resultaten visade hög förklaringsgrad (97 %) och beröringsfritt tillvägagångssätt för att testa tryckhållfasthet hos stabiliserade sediment. Seismiska metoder fungerar bra och kan användas för att testa det stabiliserades sediment i labb och fält via seismisk CPT, ytvågsseismik eller cross hole seismik.
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| 8. |
- Oliva Rivera, Alexander, et al.
(författare)
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Accelerated Carbonation of Binders Containing SCM at High CO2 Concentration
- 2023
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Ingår i: Nordic Concrete Research. - : Nordic Concrete Federation. - 0800-6377 .- 2545-2819. ; 69:2, s. 1-10
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Tidskriftsartikel (refereegranskat)abstract
- Accelerated carbonation of recycled concrete aggregates (RCA) could be an efficient way to reduce the carbon footprint. High CO2-concentration under optimal relative humidity could accelerate the CO2 binding capacity of the hydrated cement paste in the RCA. The latter is the topic of this paper. The study looks into the forced carbonation of crushed cement pastes as a basis to understand the CO2 uptake in relation to various binders containing supplementary cementitious materials (SCM) such as fly ash (FA) and ground granulated blast furnace slag (GGBS). Samples include three cement pastes: ordinary Portland cement, substitution rate of 30 % FA and 50 % GGBS respectively at a water/binder ratio of 0.45. All binders were graded to 0/2, 2/4 and 4/8 mm fraction sizes and preconditioned before exposed to CO2 concentration of 10 % under controlled temperature at 20 C-degrees and 65 % RH. All tested binders presented a high CO2 uptake within the first hours of exposure with clear differences concerning the fraction sizes and the composition. The phase content before and after carbonation was observed by X-ray diffraction and the portlandite and calcite were quantified by thermogravimetric analyses and their derivative curves for fraction size 4/8 mm.
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| 9. |
- Peterson, Viktor, et al.
(författare)
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Static and Dynamic Four-Point Flexural Tests of Concrete Beams with Variation in Concrete Quality, Reinforcement Properties and Impact Velocity
- 2021
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 65:2, s. 19-38
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Tidskriftsartikel (refereegranskat)abstract
- This paper discusses the results from three experimental test series previously conducted. The tests consist of quasi-static monotonic and dynamic four-point flexural tests on reinforced concrete beams. The effect of varying material and load parameters on the plastic strain distribution and energy absorbed by the reinforcement is discussed. The main findings are the significant effect of the post-elastic region of the steel reinforcement and the impact velocity during dynamic loading. The results will be used to validate and construct numerical models in future work, where the findings presented can be investigated further.
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| 10. |
- Rajczakowska, Magdalena, et al.
(författare)
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Is Cement Paste Modified with Carbon Nanomaterials Capable of Self-Repair after a Fire?
- 2022
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter. - 0800-6377 .- 2545-2819. ; 67:2, s. 79-97
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Tidskriftsartikel (refereegranskat)abstract
- This manuscript presents preliminary results on the cement paste potential, with and without carbon nanomaterials, to heal high-temperature cracks. Cement paste beams were subjected to thermal loading of 200 & DEG;C and 400 & DEG;C after 28 days of water curing. High temperature caused the formation of microcrack networks on the specimen's surface. Self-healing was achieved by exposing the cracked samples to cyclic water immersion. The efficiency of the process was evaluated based on the crack closure and mechanical properties recovery after 24 days. The results indicated a distinct dependence of the healing on the loading temperature. Carbon nanotubes had a positive effect on self-repair efficiency.
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| 11. |
- Rogers, Patrick, et al.
(författare)
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Chloride Ion Diffusion Resistance of Bulk Hydrophobic Concrete : Comparison of w/c and Dosages
- 2023
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 68:1, s. 17-38
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Tidskriftsartikel (refereegranskat)abstract
- Post-cast application of hydrophobic agents onto hardened concrete is successful at reducing external ion diffusion into cement paste, this work examines pre-cast application of hydrophobic admixtures in fresh concrete. Concretes, with water to cement ratios (w/c) 0.45 and 0.50 (CEM I; low C3A), were mixed. Adding alkyltrialkoxysilane or triacylglycerol admixtures ranging from 1 to 3 wt%cem in these concretes were evaluated. Increasing the dosage of hydrophobic admixtures decreased the compressive strength. The usage of these admixtures did not hinder the further development of the microstructure as all concretes gained strength after one year, but not in the same percentage increase as the reference concrete. Chloride ion diffusion, after exposure to 3 wt% NaCl solution at 20 °C for 91 days, in concretes with 1 wt%cem admixture showed slight reductions in diffusion rate (8-17%) compared to the reference. At 3 wt%cem, triacylglycerol admixtures showed better hindering effects of inward chloride diffusion, this was especially evident in w/c = 0.45. Equivalent addition of alkyltrialkoxysilane-based admixtures increased the diffusion of chloride ions transferred into the cement matrix.
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| 12. |
- Roy, Rahul, 1996-, et al.
(författare)
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Encapsulation Techniques and Test Methods of Evaluating the Bacteria-Based Self-Healing Efficiency of Concrete : A Literature Review
- 2020
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Ingår i: Nordic Concrete Research. - : Nordic Concrete Federation. - 0800-6377 .- 2545-2819. ; :1/2020, s. 63-85
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Tidskriftsartikel (refereegranskat)abstract
- Crack formation in concrete structures due to various load and non-load factors leading todegradation of service life is very common. Repair and maintenance operations are, therefore,necessary to prevent cracks propagating and reducing the service life of the structures.Accessibility to affected areas can, however, be difficult as the reconstruction and maintenanceof concrete buildings are expensive in labour and capital. Autonomous healing by encapsulatedbacteria-based self-healing agents is a possible solution. During this process, the bacteria arereleased from a broken capsule or triggered by water and oxygen access. However, itsperformance and reliability depend on continuous water supply, protection against the harshenvironment, and densification of the cementitious matrix for the bacteria to act. There are vastmethods of encapsulating bacteria and the most common carriers used are: encapsulation inpolymeric materials, lightweight aggregates, cementitious materials, special minerals,nanomaterials, and waste-derived biomass. Self-healing efficiency of these encapsulatedtechnologies can be assessed through many experimental methodologies according to theliterature. These experimental evaluations are performed in terms of quantification of crackhealing,recovery of durability and mechanical properties (macro-level test) andcharacterization of precipitated crystals by healing agent (micro-level test). Until now,quantification of crack-healing by light microscopy revealed maximum crack width of 1.80mmhealed. All research methods available for assesing self-healing efficiency of bacteria-basedhealing agents are worth reviewing in order to include a coherent, if not standardizedframework testing system and a comparative evaluation for a novel incorporated bacteria-basedhealing agent.
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| 13. |
- Saback de Freitas Bello, Vanessa, et al.
(författare)
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Asset Management of Existing Concrete Bridges Using Digital Twins and BIM: a State-of-the-Art Literature Review
- 2022
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter. - 0800-6377 .- 2545-2819. ; 66:1, s. 91-111
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Forskningsöversikt (refereegranskat)abstract
- The need to optimize investments in bridge maintenance has created a demand for improved bridge management systems (BMS). Outdated practices in bridge inspection and constant advances in information technology have also contributed to this demand. The use of Digital Twins (DT), although well established in other industries, is still incipient for asset management and structural analysis of bridges. There is a great deal of research on Building Information Modelling (BIM) for bridge inspection, but its post-construction potential is still under-explored. This study presents a state-of-the-art review of the literature on asset management for bridges using digital models such as BIM and digital twins. The review was conducting using a systematic approach. Despite the rapid increase in research on DT and the amount of existing research on BIM, several gaps remain to be addressed, such as the lack of consensus about the definition of digital twins, which has led to wrongful categorisation of digital models as DT. The complex data flow and software compatibility required to develop a functional DT have hindered the exploitation of their full potential so far. The integration of BIM post-construction to BMS and existing automation technologies can also significantly improve current practices of bridge management.
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| 14. |
- Sadagopan, Madumita, 1987-, et al.
(författare)
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Effects of Slag Addition and Mechanical Pre-Processing on the Properties of Recycled Concrete in Terms of Compressive Strength and Workability
- 2021
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 64:1, s. 11-29
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Tidskriftsartikel (refereegranskat)abstract
- Concrete waste as crushed concrete aggregates (CCA) in structural concrete prolongs the technical life of the reference concrete accomplishing closed loop recycling. CCA concrete reaches the reference concrete compressive strength and workability by the densification of CCA and cement paste. Our previous study demonstrates CCA densification by mechanical pre-processing, aggregate quality improvements discerned by increased packing density giving reference concrete strength and workability. This study addresses paste densification with blast furnace slag (GGBS) to replace 30 (wt.%) of Portland cement at reference concrete w/b ratio 0.5 and a lower w/b 0.42. Two CCA replacements are investigated: fine aggregates, CCA50; overall aggregate replacement, CCA100. Compressive strength results show that both CCA50, CCA100 mixes achieve reference values at w/b 0.42, only CCA100 achieves reference value at w/b 0.5 as a climate-optimized concrete. The CCA50 mix-w/b 0.5 reaches reference strength when paste densification by GGBS is combined with CCA densification from mechanical pre-processing of aggregates. The 7-day strength of CCA100 with GGBS increases by 11% by mixing with pre-soaked GGBS. Statistical analysis of CCA100 strength results shows significant improvements with GGBS compared to mechanical pre-processing. Significant improvements are possible in CCA50 mix for a combination of mechanical pre-processed aggregates and GGBS replacement.
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| 15. |
- Silfwerbrand, Johan
(författare)
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Concrete and Sustainability - Some Thoughts from a Swedish Horizon
- 2020
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Ingår i: Nordic Concrete Research. - : NORDIC CONCRETE FEDERAT. - 0800-6377 .- 2545-2819. ; 63:2, s. 79-87
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Tidskriftsartikel (refereegranskat)abstract
- Concrete production, especially the cement production, stands for 5-8 percent of the global CO2 emissions. Since concrete is the most frequently used man-made construction materials, this fact is not surprising. Concrete is also the only realistic alternative in order to improve the living circumstances in many countries around the world. Due to its size, the concrete sector has a great responsibility for limiting the consequences of the on-going climate change. The Swedish cement producer Cementa has an ambitious zero vision stating zero CO2 emissions in year 2030. The measures include energy efficiency, bio mass instead of fossil fuels, blended cements, CO2 uptake through carbonation and Carbon Capture Storage (CCS). This paper discusses these measures but also others such as optimization of the concrete mix, optimization of the structural geometry and prolongation of the service life. The paper is ended by a section on adaptation since concrete will also have an important role concerning protection of the built environment for climate change. Protection structures against flood, reconstruction of dams, new waste-water systems and bright permeable concrete pavements reflecting sunlight and improving drainage after heavy rain constitute some examples.
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| 16. |
- Strömberg, Larissa, et al.
(författare)
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Making Concrete Pavements Competitive by Using the Standardized Framework for Comparisons of Infrastructure Projects in Terms of Cost-Efficiency and Climate Impact
- 2020
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 62:1, s. 21-39
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Recension (refereegranskat)abstract
- espite the new Swedish client requirement to reduce the climate impact from the construction of roads, there has been relatively little research so far on how the optimization measures regarding the environmental impact of road pavements can be integrated in the traditional design. An increase in axle weights, changes of the traditional ways of travel, e.g. the use of automated and guided vehicles, and stricter customer requirements on reducing the climate impact require new approaches to steer the road and pavement industry towards more climate neutral solutions. This paper analyzes the latest standards for sustainability assessment of engineering works in an attempt to adjust these standards for assessing various road design options in a comparable and fair way, also when various materials are included.
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| 17. |
- Veganzones Muñoz, José Javier, 1989-, et al.
(författare)
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Assessment of Effective and Minimal Slab Widths for Evaluating the Shear Capacity of RC Overhang Slabs
- 2023
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377. ; 68:1, s. 64-85
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Tidskriftsartikel (refereegranskat)abstract
- The effective width is a relevant parameter for the design of bridge overhang slabs under concentrated loads. Experimental tests have been used to assess expressions for its calculation. However, the load capacity increases with the width until a transition area is reached. Test specimens may have lacked enough width to reach full shear capacity, affecting thus the evaluation of the results. On the other hand, within the transition area, a threshold value has been hypothesized to match the effective width. This paper aims to provide recommendations for minimal widths that guarantee the full capacity of overhang slabs and to assess the calculation of the effective width by means of the threshold value and other formulations. The effect of the edge beam is also considered. A campaign of validated non-linear FE-simulations based on experiments on range of width-span ratios was performed. The results suggest using a width-span ratio of at least 4.0 for slabs without an edge beam and 5.3 for slabs with an edge beam for the experimental practice. The efficiency of the formulation for the effective widths is diffuse and the use of threshold value leads to unsafe predictions. Instead, linear-elastic FE-analyses are recommended for the design practice.
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| 18. |
- Wahlbom, David, et al.
(författare)
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Cryosuction Experiments on Concrete Containing Ground Granulated Blast-Furnace Slag : Influence of Temperature, Air Entrainment And Salt
- 2023
-
Ingår i: Nordic Concrete Research. - : Sciendo. - 0800-6377. ; 68:1, s. 1-15
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Tidskriftsartikel (refereegranskat)abstract
- Frost deterioration of concrete is an important durability issue for structures exposed to high degree of saturation, low temperatures and de-icers. The material can then be severely damaged with internal cracking and/or scaling of the surface, which can lead to e.g. reduced protection of the reinforcement and loss of load bearing capacity. Experiments with liquid uptake in concrete using different temperature cycles was made to study cryosuction. The material used was concrete with different air content and different replacement levels of ground granulated blast-furnace slag (GGBS). The concrete samples were preconditioned by capillary suction. Three temperature conditions were used: constant temperatures of +20 degrees C and-20 degrees C, and temperature that cycled between-20 degrees C and +20 degrees C. As liquid medium, deionized water and a 3% NaCl salt solution were used. Air entrainment generally increased the liquid uptake. The amount of GGBS and the NaCl concentration in the liquid did not have any significant impact on the liquid uptake in these experiments.
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| 19. |
- Westerlind, Helena, et al.
(författare)
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Towards the Application of Mesostructures in 3D Concrete Printing : Evaluating Load-bearing Performance
- 2023
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377. ; 69:2, s. 87-100
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Tidskriftsartikel (refereegranskat)abstract
- In concrete structures, material performance is typically determined at the level of the concrete mix (the microscale) and the overall shape and dimensions of a building element (the macroscale). However, recent developments in the field of 3D Concrete Printing (3DCP) are demonstrating that the design of concrete now also can take place at a previously impossible intermediate scale involving the shaping and placement of the material at the level of the printing nozzle (the mesoscale). By focusing directly on the design of print paths, advanced surface effects and internal porous material distributions can be achieved that significantly affect the aesthetic experience and structural performance of 3DCP structures. This ability to design the distribution of concrete according to local architectural, structural, and functional design criteria is an especially interesting application of 3DCP that could be exploited to customise material performance while at the same time optimising material use and reducing the self-weight of building elements. This paper specifically examines how four different three-dimensional print patterns produce distinct material structures at the mesoscale (mesostructures) and presents an experimental procedure for evaluating their load-bearing capacity.
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| 20. |
- Yaqoob, Saima, et al.
(författare)
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Evaluation of Rapid Repair of Concrete Pavements Using Precast Concrete Technology : A Sustainable and Cost-Effective Solution
- 2021
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Ingår i: Nordic Concrete Research. - : Walter de Gruyter GmbH. - 0800-6377 .- 2545-2819. ; 65:2, s. 107-128
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Tidskriftsartikel (refereegranskat)abstract
- Concrete and asphalt are the two competitive materials for a highway. In Sweden, the predominant material for the highway system is asphalt. But under certain conditions, concrete pavements are competitive alternatives. For example, concrete pavements are suitable for high-traffic volume roads, roads in tunnels, concentrated loads (e.g., bus stops and industrial pavement). Besides the load-carrying capacity, the concrete pavement has many advantages such as durability (wear resistance), resistance against frost heave, environment (pollution, recycling, and low rolling resistance leading to fuel savings), fire resistance, noise limitations, brightness, evenness and aesthetics. Concrete pavements are long-lasting but need final repair. Single slabs may crack in the jointed concrete pavement due to various structural and non-structural factors. Repair and maintenance operations are, therefore, necessary to increase the service life of the structures. To avoid extended lane closures, prevent traffic congestions, and expedite the pavement construction process, precast concrete technology is a recent innovative construction method that can meet the requirement of rapid construction and rehabilitation of the pavement. This paper evaluates rapid repair techniques of concrete pavement using precast concrete technology by analysing three case studies on jointed precast concrete pavements. The study showed that the required amount of time to re-open the pavement to traffic is dramatically reduced with jointed precast concrete panels.
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