bluuebunny/crossref_metadata_2025_split huggingface dataset:
A Compact Review on the Waste-Based Lightweight Concrete: Advancement and Possibilities
Authors: Islam M. M. U. , Li J. , Roychand R. , Saberian M. 
Published: July 2023

AbstractLightweight concrete (LWC) has been used for more than 2000 years, and the technical development of waste-based LWC is still proceeding. Notably, the very first representative concrete mix of infrastructural LWC was introduced for building a family house in Berlin, Germany, a few decades ago. The unique and distinctive combination of waste-based LWC successfully creates an appealing alternative to traditional concrete aggregates in terms of durability, robustness, cost, energy-saving, transportation, environmental advantages, innovative architectural designs and implementations, and ease of construction. Numerous researchers have attempted to utilize waste materials to produce LWC, aiming to bring both ecological and economical solutions to the construction industry over the past few decades. Waste materials, such as crushed glass, waste tire rubber, masonry rubber, chip rubber, plastics, coconut shells, palm oil fuel ash, palm kernel shells, fly ash, and rice husks, possess lower specific gravity than traditional concrete aggregates. Thus waste-based LWC can be a significant replacement for conventional raw materials (cementitious material and aggregates) as it requires less strength than conventional concrete for both structural and non-structural applications. Although waste-based LWC is well recognized and has proven its scientific potential in a broad range of applications, there are still uncertainties and hesitations in practice. Therefore, the primary objective of this study was to demonstrate the current state-of-the-art understanding and advancement of waste-based LWC over the past decades. Furthermore, an equally critical discussion is reported to shed light on the potential benefits of LWC. We highlight how the performance of LWC has been enhanced significantly over the period, and understanding of the properties of waste-based LWC has advanced.
Creep of Slag Blended Cement Concrete with and Without Activator
Authors: Thanh H. T. , Tapas M. J. , Chandler J. , Sirivivatnanon V. 
Published: July 2023

AbstractPartly replacing Portland cement (PC) with lower carbon footprint cementitious materials such as ground granulated blast furnace slag (slag) is considered as a practical method for reducing CO2 emissions in the cement concrete industry. To mitigate the slow reactivity of slag in a cementitious system and enhance early-age strength, the addition of a chemical activator is a solution. However, the effect of the activator on creep behaviour of slag-blended cement concretes remains unclear. This work presents the effect of sodium sulfate (Na2SO4) activator on the compressive creep of PC concrete blended with 50 and 70 wt% slag. Four concrete mixes (with and without 2.5% Na2SO4 activator) containing 395 kg of cementitious material were prepared. The creep strain measurements were conducted on 150 × 300 mm cylindrical specimens for 140 days under sustained compressive load. The results showed that the 70% slag concrete had lower creep strain than 50% slag-blended cement concrete. The presence of Na2SO4 helped reduce the creep strain of 50% slag concrete but slightly increased that of 70% slag-blended cement concrete. In addition, the applicability of the predictive model in AS3600:2018 for the creep behaviour of high slag content concrete was assessed.
Thermal Transfer Effects of CRTS II Slab Track Under Various Meteorological Conditions
Authors: Zhou R. , Yuan W. H. , Du Y. D. , Liu H. L. , Zhang L. H. 
Published: July 2023

AbstractWith the evolution of climate change, the thermal transfer effects of ballastless track in high-speed railways under complicated environmental conditions becomes increasingly important, governed by a number of meteorological factors, including solar radiation, ambient temperature, wind speed and direction, humidity, and many others (Matias SR, Ferreira PA, Constr Build Mater 322:126445, 2022).
Effect of Carbonation on the Microstructure and Phase Development of High-Slag Binders
Authors: Tapas M. J. , Yan A. , Thomas P. , Holt C. , Sirivivatnanon V. 
Published: July 2023

AbstractThe drive for sustainable concrete production favors the use of high replacement levels of supplementary cementitious materials (SCMs) in the concrete mix. The use of SCMs such as fly ash and slag, however, although they improve the sustainability of concrete production as well as most concrete durability properties, increases the carbonation rate. Carbonation decreases the pH of the concrete pore solution, making the steel reinforcement susceptible to corrosion. The effect of carbonation is, however, not confined to the change in pH of the pore solution. We investigated changes in the microstructure and phases of high-slag binders due to carbonation. The carbonation resistance of mortars with 50 and 70% slag replacement were investigated at exposure conditions of 2%CO2, 50%RH, 23 °C. The carbonated and non-carbonated parts of the mortars were subjected to various characterization techniques to investigate the effect of carbonation on microstructure and phase development. Results confirmed the absence of portlandite in all the carbonated regions (“colorless” by phenolphthalein test, which indicated that the change in color of the phenolphthalein solution was due to the absence of portlandite to buffer the pH). Significant reduction in the amount of C-S-H, as well as increase in the amount of calcium carbonate, were been observed in the carbonated regions. Aragonite, a polymorph of CaCO3, was very prominent in all the carbonated mortars.
Accelerated Mortar Bar Test to Assess the Effect of Alkali Concentration on the Alkali–Silica Reaction
Authors: Boyd-Weetman B. , Thomas P. , DeSilva P. , Sirivivatnanon V. 
Published: July 2023

AbstractWe report the outcomes of a study into the influence of alkali concentration on expansion induced by the alkali–silica reaction (ASR), a deleterious reaction that causes cracking and durability loss in concrete structures. We assessed the effect of alkali concentration on mortar bar expansion using a modified form of AS1141.60.1, the accelerated mortar bar test (AMBT). Mortar prisms were prepared with a reactive aggregate and immersed in alkali solutions of varying concentrations (from 0.4 to 1.0 M NaOH) and saturated limewater at 80 °C. Expansion was monitored for 28 days. The degree of expansion was observed to increase with increasing alkali concentration and an induction period prior to expansion was observed for the 0.4 M NaOH. No expansion was observed for mortar bars immersed in the control saturated lime water bath. Additionally, no expansion was observed for mortars using blended cements containing fly ash (FA) and ground granulated blast furnace slag, suggesting the AMBT is a viable technique for demonstrating the efficacy of mitigation strategies.
Machine Vision-Based Scanning Strategy for Defect Detection in Post-Additive Manufacturing
Authors: Zhang S. , Chen Z. , Granland K. , Tang Y. , Chen C. 
Published: July 2023

AbstractThe surge in 3D printer availability, and its applications over the past decade as an alternative to industry-standard subtractive manufacturing, has revealed a lack of post-manufacturing quality control. Developers have looked towards automated machine learning (ML) and machine-vision algorithms, which can be effective in developing such additive manufacturing (AM) technologies for industry-wide adoption. Currently, most research has explored in-situ monitoring methods, which aim to detect printing errors during manufacturing. A significant limitation is the single, fixed monitoring angle and low resolution, which fail to identify small or hidden defects due to part geometry. Therefore, we investigated a novel ex-situ scanning strategy that combines the advantages of robotics and machine vision to address the limitations; specifically, the viability of image-recognition algorithms in the context of post-fabrication defect detection, and how such algorithms can be integrated into current infrastructure by automatically classifying surface faults in printed parts. A state-of-the-art and widely accepted ML-based vision model, YOLO, was adapted and trained by scanning for prescribed defect categories in a sample of simple parts to identify the strengths of this method over in-situ monitoring. An automated scanning algorithm that uses a KUKA robotic arm and high-definition camera is proposed and its performance was assessed according to the percentage of accurate defect predictions, in comparison with a typical in-situ model.
Spalling Resistance of Hybrid Polyethylene and Steel Fiber-Reinforced High-Strength Engineered Cementitious Composite
Authors: Rawat S. , Zhang Y. X. , Lee C. K. 
Published: July 2023

AbstractWe analyzed the effect of elevated temperatures on the integrity of high-strength engineered cementitious composite (ECC) made with a hybrid combination of polyethylene (PE) and steel fibers. The 50 mm cube specimens were subjected to temperature ranging from 200 to 800 °C at three different heating rates: 1, 5, and 10 °C/min. Five different types of mixes with varying content of supplementary cementitious materials and fibers were evaluated. No spalling was observed at 1–5 °C/min heating rate and <400 °C. However, at a heating rate of 10 °C/min for temperature 600–800 °C, all ECC specimens with a PE fiber volume of 1.25 and 1% steel fiber spalled explosively. Moreover, cementitious matrix with silica fume was more prone to spalling at 800 °C and the use of slag or quaternary blend of slag and dolomite at an optimum content was effective in maintaining the integrity of the ECC specimens even at very high heating rates. Thus, the type of cementitious matrix is equally important to consider, as well as fiber type and content, while analyzing the spalling resistance of ECC.
Modeling the Alkali–Silica Reaction and Its Impact on the Load-Carrying Capacity of Reinforced Concrete Beams
Authors: Nguyen T. N. , Li J. , Sirivivatnanon V. , Sanchez L. 
Published: July 2023

AbstractThe alkali–silica reaction (ASR) is one of the most harmful distress mechanisms affecting concrete infrastructure worldwide. The reaction leads to cracking, loss of material integrity, and consequently compromises the serviceability and capacity of the affected structures. In this study, a modeling approach was proposed to simulate ASR-induced expansion considering three-dimensional stress/restraint conditions, and its impact on the structural capacity of reinforced concrete members. Both the losses in concrete mechanical properties and prestressing effects induced by the expansion under restraints are taken into account in the model. Validation of the developed model is conducted using reliable experimental datasets derived from different laboratory testings and field exposed sites. With the capability of modelling both ASR-induced expansion and its impact on structural capacity, the model provides valuable results to specify effective repair and/or mitigation strategies for concrete structures affected by ASR.
Guidelines for Enzymatic Soil Stabilization
Authors: O’Donnell B. , Swarup A. , Sidiq A. , Robert D. , Setunge S. 
Published: July 2023

AbstractThere are numerous manuals to guide practitioners in utilizing traditional additives in the construction of road, rail and dam construction but they fall short of specific guidance for non-standard additive-based ecofriendly and cost-effective soil stabilization. Increased attention has recently been on the use of non-standard additives for stabilizing weak soils due to environmental and cost concerns associated with traditional additives. We summarize the specific guidelines of using environmental-friendly enzymes to treat weak soils. We elaborate on the requirements and specifications for the Eko-Soil multi-enzyme product that is manufactured from water and proteins extracted from fermented exudes of plants. Specific tests (laboratory and field) and conditions required for soil stabilization using Eko-Soil enzyme are elaborated using the experience of past construction projects. The guide also elaborates enhancing the efficiency of enzymatic soil stabilization by correctly incorporating the required mixing proportions and pre-requisite condition tests. Professionals and practitioners will benefit from using novel eco-friendly sustainable stabilization techniques in the treatment of weak soils covering many applications including roads, foundations, water containment areas, landfills, working platforms and slope erosion control.
Transfer and Substrate Effects on 2D Materials for Their Sensing and Energy Applications in Civil Engineering
Authors: Zhang Q. , Zheng C. , Sagoe-Crentsil K. , Duan W. 
Published: July 2023

AbstractThe recent emergence of two-dimensional (2D) materials such as graphene and transition metal dichalcogenides (TMDs) of the family (Mo, W)(S, Se)2 has attracted interest from a broad range of engineering applications, including advanced sensing and energy harvesting and conservation, because of their distinctive properties. However, it is critical important to achieve intact delamination and transfer of these atomically thin materials, as well as to understand the effects of the target substrates on their optical and electronic properties. Therefore, we developed and compared techniques for transferring as-grown WS2 crystals to arbitrary substrates. Polystyrene-assisted wet transfer can realize improved preservation of monolayer WS2 crystals than the commonly used poly(methyl methacrylate) (PMMA)-assisted wet transfer method, due to minimal chemical etching involved in the 2D material delamination process. The intercalation of alkali ions in the PMMA-based transfer method induces chemical doping over the transferred 2D crystals, leading to the formation of trions. Moreover, the edges of the crystals on hydrophilic substrates, such as sapphire or SiO2/Si, are subject to ambient water intercalation, which locally affects the photoluminescence behavior of the monolayer WS2 by doping and changing of the dielectric environment. This non-uniform optical behavior is absent when the crystal is transferred onto a hydrophobic substrate through which ambient water cannot penetrate. These results have important implications for the choice of target substrate and transfer method adopted for 2D TMD-based applications such as next-generation strain sensing, photodetectors, gas sensing, bio sensing, solar energy harvesting and radiative cooling in which uniform behavior of the channel material is required.
Experimental and Numerical Studies on the In-Plane Shear Behavior of PVC-Encased Concrete Walls
Authors: Kildashti Kamyar , Samali Bijan 
Published: July 2023

AbstractThe effective application of lightweight stay-in-place concrete forms for casting shear walls subjected to wind and seismic loading is of particular concern to practitioners. Insufficient technical data available for new kinds of wall systems, such as Polyvinyl Chloride (PVC) form walls, hinder their implementation in construction practice. To that end, an effective experimental and numerical campaign was launched at Western Sydney University to investigate the structural performance of PVC form walls when subjected to in-plane shear loading. A set of push-out specimens was designated to conduct monotonic in-plane shear tests until failure. All failure phenomena, capping strengths, and ductility capacities were monitored. Test results indicated that the embedded PVC latticed webs could efficiently protect the concrete web from sudden crushing and improve ductility capacity and failure pattern of the specimens. Nonlinear finite element analysis on test specimens was also conducted and good correlation with experiment results was achieved.
Economic Impacts of Environmentally Friendly Blocks: The Case of Nu-Rock Blocks
Authors: Tam V. W. Y. , Le K. N. , Illankoon I. M. C. S. , Tran C. N. N. , Rahme D. , Liu L. 
Published: July 2023

AbstractThere are numerous industry byproducts that have negative environmental impacts. Pond ash accumulated from coal power plants is one such byproduct that creates major environmental and social issues, especially with regard to decommissioning a coal power plant. Using pond ash in the block manufacturing process is a promising solution proposed by Nu-Rock. This research study evaluated the economic impact throughout the life cycle of Nu-Rock blocks. Nu-Rock block production use a technology called “Nu-creeting” in ash dams to prevent dust generation followed by the block manufacturing process using pond ash as a raw material. Nu-Rock technology can process approximately 250,000 tonnes of ash per annum and manufacture the equivalent of up to 330,000 tonnes volume of traditional building materials. This manufacturing process already generates jobs and pays tax and royalty fees to local governments, which is an added advantage. The total operating cost for 1 tonne of Nu-Rock blocks amounts to approximately AUD48, and the cost of a Nu-Rock block is AUD1.50–2.40, which is within the range of common bricks. Although there is a considerable initial cost to this process, it derives significant economic benefits in terms of manufacturing blocks using industrial byproducts, job creation and even tax revenue. Apart from these economic benefits, the Nu-Rock block manufacturing process generates environmental benefits through the reuse of pond ash from decommissioned coal power plants.
Composition of Alkali–Silica Reaction Products in Laboratory and Field Concrete
Authors: Tapas M. J. , Vessalas K. , Thomas P. , Gowripalan N. , Sirivivatnanon V. 
Published: July 2023

AbstractThis study investigated the composition of alkali–silica reaction (ASR) products formed in mortar and concrete that underwent accelerated ASR testing using two test methods: the accelerated mortar bar test (AMBT) and the simulated pore solution immersion test (SPSM). The composition of the ASR products formed in the accelerated tests was compared with those in a 25-year old bridge in New South Wales demolished due to ASR. Results showed that the ASR products inside an aggregate contained calcium (≈20%), silicon (≈60%), and alkalis (≈20%) regardless of the ASR test method used. The ASR products in the AMBT sample only contained sodium, whereas the ASR products in the SPSM test and the demolished bridge both contained significant amounts of sodium and potassium, which indicated that the type of alkali in the ASR product is largely affected by the dominant alkali in the pore solution. However, considering that the total alkali content (Na + K) in the ASR products was similar regardless of the ASR test method used, this suggests that the total alkali content has more influence on the rate of expansion than the type of alkali. The composition of the ASR products also notably varied depending on the location in the concrete. ASR products closer to the cement paste had a higher calcium and lower alkali content than those inside an aggregate, which suggests that the calcium as well as the alkali content of the ASR products plays a significant role in the degree of ASR expansion.
Life Cycle Assessment (LCA) of Recycled Concrete Incorporating Recycled Aggregate and Nanomaterials
Authors: Xing W. , Tam V. , Le K. , Hao J. L. , Wang J. , Yang P. 
Published: July 2023

AbstractNanotechnology is widely used in construction to advance high performance and durability materials, as represented by concrete, in which nanomaterials such as nanosilica (SiO2), nano-alumina (Al2O3), and nanotitanium oxide (TiO2) are used to replace cement as a partial binder. Suitable amounts of adding these nanomaterials are beneficial with regard to the mechanical, economic, and environmental aspects of concrete.
Analysis of the Compressive Strength of CO2 Concrete While Eliminating Overshadowing Concrete Variables
Authors: Tam V. W. Y. , Butera A. , Le K. N. , Liu L. 
Published: July 2023

AbstractAlthough other technologies for the improvement of recycled aggregate, such as removal of adhered cement, improvement of aggregate by methods including nanomaterials, sequential mixing and precoating, the ideology of sequestration of CO2 into cementitious materials provides great potential for both the enhancement and utilisation of recycled concrete materials and sequestration of CO2.
Effects of Graphene Oxide Content on the Reinforcing Efficiency of C–S–H Composites: A Molecular Dynamics Study
Authors: Chen W. , Xiang J. , Gao Y. , Zhang Z. 
Published: July 2023

AbstractDetermining the graphene oxide (GO) content is the key to applying GO to reinforce the mechanical performance and durability of cementitious composites. However, most of the previous studies are conducted from the perspective of experiments and lack elaboration on the mechanism of the GO-reinforced cementitious composite under different GO content. Hence, we investigated the effect of GO content on the reinforcing efficiency of calcium–silicate–hydrate (C–S–H) to trade off the enhancement of GO in cementitious composites and the corresponding economic benefits. The results demonstrated that an appropriate number of GO nanosheets can reinforce the cementitious composite with simultaneous high enhancing efficiency and economic benefits. The microdamage evolution of GO/C–S–H composites and the GO reinforcing mechanisms are reported. Our findings deepen the understanding of the enhancing mechanisms of GO embedded in C–S–H nanocomposites and help to determine the suitable GO content in practical engineering.
Investigation of ASR Effects on the Load-Carrying Capacity of Reinforced Concrete Elements by Ultra-Accelerated Laboratory Test
Authors: Cao J. , Gowripalan N. , Sirivivatnanon V. , Nairn J. 
Published: July 2023

AbstractThe alkali–silica reaction (ASR) can cause expansion, cracking, and degradation of the mechanical properties of affected concrete. Concerns about the safety of ASR-damaged reinforced concrete structures have driven the demand for studying the effects of ASR on residual load capacity of the deteriorated structure. Conventionally, field load testing methods are used to assess the residual load capacity of ASR-affected structures. In this study, a novel accelerated laboratory test using the LVSA 50/70 autoclave to accelerate ASR was applied to investigate the flexural and shear behavior of small-scale reinforced concrete beams affected by ASR. The specimens were subjected to three cycles of 80 °C steam curing at atmospheric pressure in the autoclave, with 60 h/cycle. Significant expansion and ASR damage were observed. Load carrying capacity tests on the small-scale reinforced concrete beams showed that, at the expansion levels achieved, the flexural capacity of the reinforced concrete beams was not significantly affected. Shear resistance of the reinforced concrete beams, however, was found to increase compared with their 28-day counterparts, which could be attributed to the prestressing effect due to ASR expansion. It appears that the multicycle 80 °C steam-curing autoclave test is suitable for investigating ASR deterioration of actual concrete mixes within a short period of time. ASR effects on the load carrying capacity of reinforced concrete elements at higher expansion levels, however, need further investigation.