Case Studies in Construction Materials最新文献_第2页

Optimizing cement-treated recycled concrete aggregates for road bases using secondary additive 优化水泥处理再生混凝土集料的道路基层使用二次添加剂

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Case Studies in Construction Materials

Pub Date : 2026-07-01 Epub Date: 2025-12-11 DOI: 10.1016/j.cscm.2025.e05687

Zainul Abedin Khan , Umashankar Balunaini , Nhu H.T. Nguyen , Susanga Costa

This study investigates the feasibility of a secondary additive treated recycled concrete aggregates (RCA) to reduce the required cement content for the construction of pavement base/subbase layers. The effectiveness of secondary additive was assessed based on extensive studies involving strength, durability and microstructural analysis considering different cement contents (2 %, 3 %, 4 %, and 5 % by weight of aggregates) and a silica-rich secondary additive (2 % and 4 %, by weight of cement). The addition of a secondary additive significantly reduced the required cement content (from 7 % to 5 %) to meet the minimum 7-day unconfined compressive strength criteria for base layers. Accordingly, 5 % cement content and 4 % additive contents are proposed in the study for base layer applications. The weight loss percentage of treated RCA specimens prepared with this optimal mix (3.1 %) is found to be less than the maximum permissible value (14 % after 12 wet-dry cycles). The 7-day cured specimens prepared with this mix showed a significantly high resilient modulus value (667 MPa). Additionally, the designed pavement section incorporating 5 % cement and 4 % additive-treated layers exhibited a 13 % reduction in pavement crust thickness compared to the non-treated pavement section. Treated RCA satisfied the requirements of pavement base/subbase layer in accordance with American, Australian, and Indian road standards and can be a viable solution towards sustainable road infrastructure. The findings demonstrate that secondary additive treated RCA can be effectively utilized in road pavement base/subbase layers with lower cement dosage and promoting sustainable road construction using recycled waste materials.

本研究探讨了二级添加剂处理再生混凝土骨料（RCA）的可行性，以减少路面基层/次基层施工所需的水泥含量。二次添加剂的有效性评估基于广泛的研究，包括强度、耐久性和微观结构分析，考虑不同的水泥含量（按骨料重量计2%、3%、4%和5% %）和富含二氧化硅的二次添加剂（按水泥重量计2%和4% %）。二级添加剂的加入显著降低了所需的水泥含量（从7 %降至5 %），以满足基层最低7天无侧限抗压强度标准。据此，在基层应用研究中提出水泥掺量为5 %，添加剂掺量为4 %。用这种最佳混合物制备的处理过的RCA试样的失重率（3.1 %）小于最大允许值（12个干湿循环后14 %）。用该混合料制备的7天固化试样显示出显著高的弹性模量值（667 MPa）。此外，与未处理的路面部分相比，含有5 %水泥和4 %添加剂处理层的设计路面部分的路面外壳厚度减少了13 %。处理后的RCA满足美国、澳大利亚和印度道路标准对路面基层/次基层的要求，是可持续道路基础设施的可行解决方案。研究结果表明，经二次添加剂处理的RCA可有效地用于低水泥用量的路面基层/亚基层，促进再生废弃物的可持续道路建设。

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引用次数: 0

Comparative life cycle assessment of chip seal preventive maintenance techniques: Cost and environmental implications 芯片密封预防性维护技术的生命周期比较评估：成本和环境影响

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Case Studies in Construction Materials

Pub Date : 2026-07-01 Epub Date: 2025-12-13 DOI: 10.1016/j.cscm.2025.e05663

Farnaz Saadat, Mohammad Zia Alavi, Fateme Labbafi

This study presents a comparative life cycle assessment and lifecycle cost analysis of seven chip-seal preventive maintenance treatments (Single, Double, and Triple chip seals; Scrub seal; Cape seal; Fiber-modified chip seal; and Rubberized chip seal) using a cradle-to-construction system boundary. Environmental impacts were quantified with SimaPro v9 (Ecoinvent) using the ReCiPe 2016 Endpoint (H) method for a functional unit of 1 m² of treated pavement and for the economic analysis, documented U.S. project costs and the Iranian price list were used and annualized with a 10 % discount rate. Results indicate that, under a cradle-to-construction boundary, Single Chip Seal and Scrub Seal have the lowest total normalized costs (1.88 and 2.6 USD/

m^{2}

), while Rubberized and Triple Chip Seals show the highest total costs (7.06 and 6.28 USD/

m^{2}

). When costs are annualized by service life, Single chip seal and Scrub seal remain the least costly (0.5 and 0.69 USD/

m^{2}

), whereas Fiber chip seal, Cape seal and Triple chip seal are the most expensive ones (1.03, 1.05, and 1.05, respectively). From an environmental standpoint, Scrub Seal has the lowest total GHG emissions (≈1545 g CO₂e) and the lowest weighted endpoint scores across Human Health, Ecosystems and Resources, whereas Cape Seal and Triple Chip Seal are the worst performers (Cape seal total GHG ≈ 5301 g CO₂e; Triple chip seal frequently attains the maximum normalized score across midpoint categories). However, when these values normalized per service year, Rubberized Chip Seal yields one of the lowest annual GHG burdens (≈177.5 g CO₂e/year), illustrating the trade-off between higher upfront material and installation impacts and longer service life. Monte Carlo uncertainty analysis (1000 runs, 95 % CI) confirms that the relative ranking of alternatives is robust. The results highlight clear cost–environment tradeoffs and the importance of life-span weighting in selecting preservation strategies.

本研究采用从摇篮到施工系统的边界，对7种切屑密封预防性维护方法（单、双、三重切屑密封、磨砂密封、角密封、纤维改性切屑密封和橡胶切屑密封）的生命周期评估和生命周期成本进行了比较分析。使用SimaPro v9 (Ecoinvent)，采用ReCiPe 2016 Endpoint (H)方法，对1 m²处理后的路面的功能单位进行了环境影响量化，并进行了经济分析，使用了记录的美国项目成本和伊朗价格表，并以10 %的折让率进行了年化。结果表明，在从支架到建筑的边界上，单片密封和磨砂密封的总标准化成本最低（分别为1.88和2.6美元/m2），而橡胶密封和三片密封的总标准化成本最高（分别为7.06和6.28美元/m2）。如果按使用寿命年化成本计算，单片密封和擦洗密封的成本最低（分别为0.5和0.69美元/平方米），而纤维密封、Cape密封和三片密封的成本最高（分别为1.03、1.05和1.05美元/平方米）。从环境的角度来看，Scrub Seal的温室气体总排放量最低（≈1545 g CO₂e），在人类健康、生态系统和资源方面的加权终点得分最低，而Cape Seal和Triple Chip Seal表现最差（Cape Seal的温室气体总排放量≈5301 g CO₂e； Triple Chip Seal经常在中点类别中获得最大的标准化得分）。然而，当这些值在每个使用年标准化时，橡胶屑密封产生的年温室气体负担最低（≈177.5 g CO₂e/年），说明了更高的前期材料和安装影响与更长的使用寿命之间的权衡。蒙特卡罗不确定性分析（1000次运行，95% CI）证实了备选方案的相对排名是稳健的。结果突出了明确的成本-环境权衡和寿命加权在选择保护策略中的重要性。

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引用次数: 0

Mix design optimisation for concrete with alternative binders and aggregates incorporating environmental, mechanical and durability performance 混合设计优化混凝土与替代粘合剂和集料结合环境，机械和耐久性性能

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Case Studies in Construction Materials

Pub Date : 2026-07-01 Epub Date: 2025-12-09 DOI: 10.1016/j.cscm.2025.e05638

A. Razmi , T. Bennett , T. Xie , P. Visintin

The design of environmentally efficient concretes remains challenging due to the conflicting requirements of reducing embodied carbon while maintaining durability and mechanical performance, particularly when recycled aggregates and supplementary cementitious materials (SCMs) are used. This study presents a performance-based optimisation framework that integrates mix design variables, service-life prediction, and life-cycle assessment (LCA) to minimise global warming potential (GWP) while meeting durability requirements. The framework combines artificial neural networks (trained on 4828 experimental mixes), phenomenological chloride diffusion modelling, and a cradle-to-gate life-cycle assessment, optimised using genetic algorithms to minimise global warming potential and natural aggregate usage while meeting chloride diffusion requirements. Results show that switching from GWP minimisation to natural aggregate conservation requires a reduction in water-to-binder ratio (w/b) by 8–30 % and an increase in binder-to-aggregate ratio (b/a) by 40–114 %, which consequently raises GWP. Among SCMs, GGBFS achieves up to 48 % lower GWP, followed by silica fume (47 %) and fly ash (35 %). Multi-objective analysis indicated that incorporating recycled aggregate at approximately 30 % balances durability, resource efficiency, and emissions, whereas full replacement significantly increases GWP unless offset by the use of large volumes of SCMs. Service-life modelling revealed that high-diffusivity concretes required up to 58

kg {CO}_{2 - eq} / m^{2}

additional emissions through increased cover depths, while SCM-enhanced mixes consistently achieved target service-lives with minimal cover penalties. By combining material optimisation with performance-based cover design, the framework identifies mix designs that balance durability, environmental efficiency, and resource conservation, supporting long-lasting, low-carbon concrete elements.

环保型混凝土的设计仍然具有挑战性，因为在保持耐久性和机械性能的同时减少隐含碳的要求相互冲突，特别是当使用回收骨料和补充胶凝材料（scm）时。本研究提出了一个基于性能的优化框架，该框架集成了混合设计变量、使用寿命预测和生命周期评估（LCA），以最大限度地降低全球变暖潜能值（GWP），同时满足耐久性要求。该框架结合了人工神经网络（在4828种实验混合物上进行了训练）、现象学氯化物扩散建模和从摇篮到gate的生命周期评估，并使用遗传算法进行了优化，以最大限度地减少全球变暖潜势和自然总量的使用，同时满足氯化物扩散要求。结果表明，从GWP最小化转变为自然骨料保护需要将水胶比（w/b）降低8-30 %，并将粘结剂与骨料比（b/a）提高40-114 %，从而提高GWP。在SCMs中，GGBFS的GWP降低率高达48% %，其次是硅灰（47% %）和粉煤灰（35% %）。多目标分析表明，采用约30% %的再生骨料可平衡耐久性、资源效率和排放，而完全替代可显著增加全球变暖潜能值，除非通过大量使用SCMs来抵消。使用寿命模型显示，通过增加覆盖深度，高扩散系数混凝土需要高达58 kgCO2−eq/m2的额外排放，而scm增强混合物始终以最小的覆盖损失实现目标使用寿命。通过将材料优化与基于性能的盖板设计相结合，框架确定了平衡耐用性、环境效率和资源节约的混合设计，支持持久、低碳的混凝土元素。

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引用次数: 0

Effects of specimen longitudinal dimensions on the compressive mechanical properties of timber: Experimental investigation and quantitative analysis 试件纵向尺寸对木材压缩力学性能的影响：试验研究与定量分析

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Case Studies in Construction Materials

Pub Date : 2026-07-01 Epub Date: 2025-12-08 DOI: 10.1016/j.cscm.2025.e05665

Jifei Liao, Zhenlin Chen, Xiao Hu, Yang Song, Huaxin Lu

Wood is recognized as a sustainable, low-carbon construction material, yet a comprehensive theoretical model explaining length-dependent size effects on its longitudinal compressive properties is lacking. Although previous studies have highlighted the importance of longitudinal compressive performance, the impact of wood species variation on this property has not been fully explored. Critically, quantitative relationships between longitudinal compressive behavior and specimen length across various species remain undefined, hindering the application of laboratory results to engineering practice. This study addresses existing knowledge gaps by examining three wood species: Pinus sylvestris var. mongolica (conifer), Elm (broadleaved) and Paulownia (broadleaved). Specimens with varying lengths were subjected to systematic longitudinal compression tests. The analysis focused on compression characteristics across different sizes and a thorough investigation of failure mechanisms. Load-displacement and stress-strain curves were used to elucidate the relationship between mechanical properties and specimen size. Longitudinal compressive strength size effect coefficients were determined using Weibull's weakest-link theory, while finite element simulations modeled axial compression behavior based on experimental data. Key findings include: (1) A significant negative correlation between longitudinal compressive strength and specimen length, with size effect coefficients of 0.08 for Pinus sylvestris var. mongolica, 0.16 for elm, and 0.18 for paulownia. (2) The elastic modulus decreased with increasing specimen length, whereas Poisson's ratio remained unaffected by size variations. (3) Finite element models accurately replicated axial compression failure patterns but required strength reduction factors to account for length-dependent size effects. The proposed model for length-dependent size effect coefficients offers a new framework for characterizing the multiscale mechanical behavior of wood.

木材被认为是一种可持续的低碳建筑材料，但缺乏一个全面的理论模型来解释长度依赖的尺寸对其纵向压缩性能的影响。虽然以前的研究强调了纵向压缩性能的重要性，但木材种类变化对这一特性的影响尚未得到充分探讨。重要的是，纵向压缩行为和不同物种的试样长度之间的定量关系仍然不确定，这阻碍了实验室结果在工程实践中的应用。本研究通过考察三种树种：蒙古松（针叶树）、榆树（阔叶）和泡桐（阔叶）来填补现有的知识空白。不同长度的试样进行了系统的纵向压缩试验。分析的重点是不同尺寸的压缩特性和对破坏机制的深入研究。采用载荷-位移曲线和应力-应变曲线分析了试样尺寸与力学性能的关系。纵向抗压强度尺寸效应系数采用Weibull最弱链接理论确定，而有限元模拟基于实验数据模拟轴向压缩行为。主要发现包括：(1)纵向抗压强度与标本长度呈显著负相关，蒙古松、榆树和泡桐的尺寸效应系数分别为0.08、0.16和0.18。(2)弹性模量随试样长度的增加而减小，泊松比不受尺寸变化的影响。(3)有限元模型准确地模拟了轴压破坏模式，但需要强度折减因子来考虑长度相关的尺寸效应。提出的长度相关尺寸效应系数模型为表征木材的多尺度力学行为提供了一个新的框架。

{"title":"Effects of specimen longitudinal dimensions on the compressive mechanical properties of timber: Experimental investigation and quantitative analysis","authors":"Jifei Liao, Zhenlin Chen, Xiao Hu, Yang Song, Huaxin Lu","doi":"10.1016/j.cscm.2025.e05665","DOIUrl":"10.1016/j.cscm.2025.e05665","url":null,"abstract":"<div><div>Wood is recognized as a sustainable, low-carbon construction material, yet a comprehensive theoretical model explaining length-dependent size effects on its longitudinal compressive properties is lacking. Although previous studies have highlighted the importance of longitudinal compressive performance, the impact of wood species variation on this property has not been fully explored. Critically, quantitative relationships between longitudinal compressive behavior and specimen length across various species remain undefined, hindering the application of laboratory results to engineering practice. This study addresses existing knowledge gaps by examining three wood species: Pinus sylvestris var. mongolica (conifer), Elm (broadleaved) and Paulownia (broadleaved). Specimens with varying lengths were subjected to systematic longitudinal compression tests. The analysis focused on compression characteristics across different sizes and a thorough investigation of failure mechanisms. Load-displacement and stress-strain curves were used to elucidate the relationship between mechanical properties and specimen size. Longitudinal compressive strength size effect coefficients were determined using Weibull's weakest-link theory, while finite element simulations modeled axial compression behavior based on experimental data. Key findings include: (1) A significant negative correlation between longitudinal compressive strength and specimen length, with size effect coefficients of 0.08 for Pinus sylvestris var. mongolica, 0.16 for elm, and 0.18 for paulownia. (2) The elastic modulus decreased with increasing specimen length, whereas Poisson's ratio remained unaffected by size variations. (3) Finite element models accurately replicated axial compression failure patterns but required strength reduction factors to account for length-dependent size effects. The proposed model for length-dependent size effect coefficients offers a new framework for characterizing the multiscale mechanical behavior of wood.</div></div>","PeriodicalId":9641,"journal":{"name":"Case Studies in Construction Materials","volume":"24 ","pages":"Article e05665"},"PeriodicalIF":6.6,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145735778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Combined influence of treated eggshell powder and polypropylene fiber on the mechanical, durability and microstructural properties of sustainable concrete: Experimental and machine learning-based analysis 处理过的蛋壳粉和聚丙烯纤维对可持续混凝土力学、耐久性和微观结构性能的综合影响：实验和基于机器学习的分析

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Case Studies in Construction Materials

Pub Date : 2026-07-01 Epub Date: 2025-12-08 DOI: 10.1016/j.cscm.2025.e05656

Samiha Islam , Md. Ikramul Hoque , Md. Habibur Rahman Sobuz , Md. Kawsarul Islam Kabbo , Abdullah Alzlfawi , Sani Aliyu Abubakar

In recent years, there has been a rise in the application of waste materials as a result of the carbon emissions associated with concrete production. This study investigates the fresh, mechanical, durability, and microstructural properties of concrete incorporating a combination of treated waste eggshell powder (ESP) at replacement levels of 5 %, 10 %, and 15 %, and polypropylene fiber (PPF) at dosages of 0.05 % and 0.10 %. Mechanical performance was evaluated through compressive, tensile, and flexural strength tests, while durability was assessed by water permeability, sorptivity, and rapid chloride permeability tests. Furthermore, the microstructures of the concrete matrix were examined using scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDX) tests. In addition, supervised machine learning (ML) models were developed to predict compressive strength. Results showed that the optimum mix of 5 % ESP and 0.10 % PPF enhanced compressive, tensile, and flexural strength by 13.47 %, 22.37 %, and 12.47 %, respectively, compared to the control. The significant durability performance was noted in the 5 % ESP and 0.10 % PPF mix, with reduced chloride permeability and water penetration. Among the ML models, XGBoost showed superior predictive accuracy, achieving an R² of 0.954 and the lowest MAE of 3.776 MPa. These study outcomes suggest that the incorporation of ESP and PPF into concrete results in elevated mechanical and durability performance, thereby committing to more sustainable and eco-friendly concrete production.

近年来，由于与混凝土生产相关的碳排放，废料的应用有所增加。本研究考察了将处理后的废蛋壳粉（ESP）替换为5 %、10 %和15 %，聚丙烯纤维（PPF）替换为0.05 %和0.10 %，结合在一起的混凝土的新鲜度、机械性能、耐久性和微观结构性能。机械性能通过压缩、拉伸和弯曲强度测试来评估，而耐久性通过透水性、吸附性和快速氯化物渗透性测试来评估。此外，采用扫描电子显微镜（SEM）和能量色散x射线光谱（EDX）测试对混凝土基体的微观结构进行了检测。此外，还开发了监督机器学习（ML）模型来预测抗压强度。结果表明，与对照相比，5 % ESP和0.10 % PPF的最佳掺量分别提高了13.47 %、22.37 %和12.47 %的抗压、抗拉和抗弯强度。在5% % ESP和0.10 % PPF的混合物中，发现了显著的耐久性能，降低了氯化物渗透率和水渗透性。在ML模型中，XGBoost的预测准确率最高，R2为0.954，MAE最低，为3.776 MPa。这些研究结果表明，在混凝土中加入ESP和PPF可以提高混凝土的机械性能和耐久性，从而实现更可持续、更环保的混凝土生产。

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引用次数: 0

Mechanical properties, durability, and life cycle assessment of recycled brick powder concrete reinforced with different fibers 不同纤维增强再生砖粉混凝土的力学性能、耐久性及生命周期评价

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Case Studies in Construction Materials

Pub Date : 2026-07-01 Epub Date: 2025-12-22 DOI: 10.1016/j.cscm.2025.e05723

Yuanyuan Zhao , Huifang Tao , Dongze Xie , Min LV , Shiqi Sun

The recycling of construction and demolition waste containing clay bricks inevitably yields waste clay brick powder as a by-product. By optimizing the particle size and replacement level of waste clay brick powder, a composite cementitious material with high mechanical strength and enhanced durability can be developed. In this study, recycled brick powder (RBP) of varying particle sizes was produced from discarded clay bricks. RBP was then used to replace cement at different substitution rates to produce recycled brick powder concrete (RBPC). Then, five types of fibers, including 12 mm long polypropylene fiber (PPF-12), 19 mm long polypropylene fiber (PPF-19), copper-coated steel fiber (CF), glass fiber (GF), and basalt fiber (BF), were added to RBPC to further enhance the performance of RBPC. The mechanical properties, durability tests, and life cycle assessment of the fiber-reinforced RBPC were also carried out. The results show that the optimal particle size and substitution rate of RBP are 0.075 mm and 5 %, respectively. CF has the best effect on improving the mechanical properties of RBPC, while PPF-12 has a stronger impact on improving the mechanical properties of RBPC than PPF-19. Scanning electron microscopy analysis showed that CF and BF had the best binding effect with cement hydration products. In addition, the durability of RBPC was improved after adding fibers. Among them, BF had the best impact on improving the high temperature resistance and corrosion resistance of RBPC, and CF had the best effect on improving the freeze-thaw resistance of RBPC, followed by BF. Life cycle assessment shows that fiber-reinforced RBPC is more sustainable and economically friendly. Among them, RBPC doped with BF has the best sustainability, while RBPC doped with PPF-12 is the most economical.

含粘土砖的建筑和拆迁垃圾的回收利用不可避免地产生废粘土砖粉作为副产品。通过优化废粘土砖粉的粒径和替代水平，可以开发出高机械强度和增强耐久性的复合胶凝材料。以废弃粘土砖为原料，制备了不同粒径的再生砖粉（RBP）。然后用RBP以不同取代率替代水泥生产再生砖粉混凝土（RBPC）。然后，在RBPC中添加12 mm长聚丙烯纤维（PPF-12）、19 mm长聚丙烯纤维（PPF-19）、镀铜钢纤维（CF）、玻璃纤维（GF）和玄武岩纤维（BF）等5种纤维，进一步提高RBPC的性能。进行了纤维增强RBPC的力学性能、耐久性试验和寿命周期评价。结果表明，RBP的最佳粒径为0.075 mm，取代率为5 %。CF对RBPC力学性能的改善效果最好，而PPF-12对RBPC力学性能的改善作用强于PPF-19。扫描电镜分析表明，CF和BF与水泥水化产物的结合效果最好。此外，添加纤维后，RBPC的耐久性得到了提高。其中，BF对提高RBPC的耐高温、耐腐蚀性能效果最好，CF对提高RBPC的抗冻融性能效果最好，BF次之。生命周期评价表明，纤维增强RBPC具有更强的可持续性和经济友好性。其中，掺BF的RBPC具有最佳的可持续性，而掺PPF-12的RBPC最具经济性。

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引用次数: 0

Impact of fiber-induced tensile strain hardening on the bearing performance of ECC and UHPC pipes: Experimental study and strength modeling 纤维诱导拉伸应变硬化对ECC和UHPC管道承载性能的影响：实验研究和强度建模

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Case Studies in Construction Materials

Pub Date : 2026-07-01 Epub Date: 2025-12-22 DOI: 10.1016/j.cscm.2025.e05726

Chung-Chan Hung, Shu-Er Chen, Ya-Jung Tsai, Cheng-Hao Yen

The mechanical and durability performance of concrete pipes is critical in modern infrastructure, particularly in regions with high load demands and stringent maintenance requirements. This study addresses these challenges by exploring the use of tensile strain-hardening cementitious materials—namely, Engineered Cementitious Composites (ECC) and Ultra-High-Performance Concrete (UHPC)—as advanced alternatives to conventional concrete. A total of seven specimens were evaluated under three-edge bearing tests in accordance with ASTM C497 to assess their damage pattern, cracking strength, ultimate strength, stiffness, and energy dissipation capacity. The effects of fiber type, fiber volume fraction, and the presence of a steel cage reinforcement were systematically explored. Experimental results demonstrated that both ECC and UHPC pipes offered significantly enhanced cracking and ultimate strengths. The inclusion of steel fibers in UHPC was particularly effective, allowing pipes with just 0.5 % fiber volume to achieve comparable or even superior stiffness and energy dissipation capacities compared to steel-reinforced conventional concrete counterparts. These findings suggest the feasibility of either reducing or completely replacing traditional steel reinforcement with high-performance fiber reinforcement. Furthermore, the study developed and validated analytical models that reasonably predict the cracking and ultimate strengths of the pipes, with an average underestimation of 5 % and 7 %, respectively.

混凝土管道的机械性能和耐久性在现代基础设施中至关重要，特别是在高负荷需求和严格维护要求的地区。本研究通过探索使用拉伸应变硬化胶凝材料（即工程胶凝复合材料（ECC）和超高性能混凝土（UHPC））作为传统混凝土的先进替代品来解决这些挑战。按照ASTM C497标准对7个试件进行了三边承载试验，评估了试件的损伤模式、开裂强度、极限强度、刚度和耗能能力。系统地探讨了纤维类型、纤维体积分数和钢笼增强物的存在的影响。实验结果表明，ECC和UHPC管道的抗裂强度和极限强度均有显著提高。在UHPC中加入钢纤维尤其有效，与钢增强的传统混凝土相比，纤维体积仅为0.5 %的管道可以获得相当甚至更好的刚度和耗能能力。这些发现表明，用高性能纤维增强材料减少或完全取代传统钢筋是可行的。此外，研究建立并验证了合理预测管道开裂和极限强度的分析模型，平均低估分别为5 %和7 %。

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引用次数: 0

Valorization of municipal solid waste incineration bottom ash in ecological cement mortar: Mechanical enhancement, effective immobilization of hazardous heavy metals, and life cycle environmental benefits 城市生活垃圾焚烧底灰在生态水泥砂浆中的增值：机械增强、有害重金属的有效固定化、全生命周期环境效益

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Case Studies in Construction Materials

Pub Date : 2026-07-01 Epub Date: 2025-12-19 DOI: 10.1016/j.cscm.2025.e05718

Jun Yan, Zhaoxi Li, Jun Wang

This study investigates the utilization of municipal solid waste incineration bottom ash (IBA), pretreated via simple co-grinding and sieving, in ecological cement mortar (ECM) designed with a modified Andreasen–Andersen particle-packing model and an ultra-low water-to-binder ratio (w/b = 0.16). Mortars with 0–15 % IBA by mass replacing natural river sand were evaluated for mechanical, microstructural, and environmental performance. Strength improved at 5–10 % IBA, with the 10 % mix reaching a 28-day compressive strength of 127.6 MPa. XRD/TGA confirmed pozzolanic reactivity, showing ∼42.9 % consumption of Portlandite (Ca(OH)₂) and additional C–A–S–H formation. SEM and MIP revealed a densified matrix and refined pore structure. Leaching concentrations of Cu, Zn, Pb, and Cr were below regulatory thresholds, and mixes with 5–10 % IBA exhibited lower values than the control. Life-cycle assessment indicated that 15 % IBA reduced global warming potential by ∼9.8 % and yielded net benefits in ecotoxicity and human-toxicity categories due to avoided-burden credits. Overall, 10 % IBA provided the best balance between mechanical performance and environmental safety, whereas 15 % maximized environmental benefits, supporting the large-scale, low-cost use of IBA in sustainable construction materials.

本研究以改良的Andreasen-Andersen颗粒填料模型和超低水胶比（w/b = 0.16）设计的生态水泥砂浆（ECM）为研究对象，研究了经简单共磨和筛分预处理的城市生活垃圾焚烧底灰（IBA）的利用。以0-15 % IBA质量代替天然河砂的砂浆进行力学、微观结构和环境性能评价。强度在5-10 % IBA时有所提高，10 %混合物的28天抗压强度达到127.6 MPa。XRD/TGA证实了火山灰的反应性，表明波特兰石（Ca(OH)2）消耗了~ 42.9 %，并形成了额外的C-A-S-H。SEM和MIP分析表明，该材料具有致密的基体和精细的孔隙结构。Cu、Zn、Pb和Cr的浸出浓度低于规定的阈值，5-10 % IBA的浸出浓度低于对照。生命周期评估表明，15 % IBA使全球变暖潜势降低了~ 9.8 %，并且由于避免了负担信用，在生态毒性和人类毒性类别中产生了净效益。总体而言，10 %的IBA在机械性能和环境安全之间提供了最佳平衡，而15 %的IBA最大限度地提高了环境效益，支持IBA在可持续建筑材料中的大规模、低成本使用。

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引用次数: 0

Pore characteristics and properties of calcium sulfoaluminate (CSA) foam concrete: Effects of foam content and water-to-binder ratio 硫铝酸钙（CSA）泡沫混凝土的孔隙特征和性能：泡沫含量和水胶比的影响

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Case Studies in Construction Materials

Pub Date : 2026-07-01 Epub Date: 2025-12-16 DOI: 10.1016/j.cscm.2025.e05708

Yun-Lin Liu , Zi-Yao Tang , Xing-Yu Zhou , Dong Guo , Yan-Shuai Wang

Calcium sulfoaluminate (CSA) cement presents a promising alternative to Ordinary Portland Cement (OPC) in the production of ultra-lightweight foam concrete for marine applications, owing to its environmentally friendly characteristics and enhanced early strength development. This study investigates mixture optimization strategies to enhance the performance of ultra-lightweight CSA cement-based foam concrete. The macroscopic properties examined include flowability, density, compressive strength, and thermal conductivity. In addition, cross-sectional images of the specimens were analyzed to quantify key microscopic pore characteristics, such as porosity, pore size distribution, and pore roundness. These properties were systematically evaluated and compared to assess the effects of foam content (ranging from 59 % to 87 %) and water-to-binder ratio (ranging from 0.70 to 0.90). The results revealed that higher foam content and water-to-binder ratio significantly increased porosity and average pore diameter of the CSA foam concrete. Moreover, both compressive strength and thermal conductivity showed an inverse relationship with the porosity, while pore roundness further influenced these key properties.

硫铝酸钙（CSA）水泥由于其环保特性和增强的早期强度发展，在生产船舶应用的超轻量泡沫混凝土方面，它是普通波特兰水泥（OPC）的一个有希望的替代品。研究了提高CSA水泥基泡沫混凝土超轻量化性能的配合比优化策略。宏观性能包括流动性、密度、抗压强度和导热性。此外，还分析了样品的横截面图像，以量化孔隙率、孔径分布和孔隙圆度等关键微观孔隙特征。系统地评估和比较了这些性能，以评估泡沫含量（范围从59 %到87 %）和水胶比（范围从0.70到0.90）的影响。结果表明，较高的泡沫掺量和水胶比显著提高了CSA泡沫混凝土的孔隙率和平均孔径。此外，抗压强度和导热系数与孔隙率呈反比关系，而孔隙圆度进一步影响了这些关键性能。

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引用次数: 0

Resource recovery for sustainable construction: Strength and microstructure characteristics of municipal solid waste incineration ash as a green alternative to cement in cementitious composites 可持续建筑的资源回收：作为水泥复合材料中绿色替代品的城市生活垃圾焚烧灰的强度和微观结构特征

IF 6.6 2区工程技术 Q1 CONSTRUCTION & BUILDING TECHNOLOGY

Case Studies in Construction Materials

Pub Date : 2026-07-01 Epub Date: 2025-12-09 DOI: 10.1016/j.cscm.2025.e05675

Siva Avudaiappan , Ramon Francisco Arrue Munoz , G. Murali , Manuel Chávez-Delgado , Ramirez-Madrid Andres , Paulraj Manidurai , Erick Saavedra Flores , Nelson Maureira-Carsalade

The building sector is confronted with significant issues related to sustainability due to high carbon emissions and resource consumption from conventional cement production. Additionally, the disposal of municipal solid waste incineration bottom ash (MSWI-BA) poses environmental risks. This study examines the potential of MSWI-BA as partial substitution of cement in cementitious composite formulations, with particular emphasis on its influence on strength and microstructure. The research aims to promote resource recovery, reduce landfill usage, lower carbon emissions, and foster eco-friendly building solutions and efficient waste utilization. Cement was partially replaced with MSWI-BA at substitution levels of 0 %, 10 %, 20 %, and 30 %, and the effects on density, porosity, water absorption, compressive strength, flexural strength, and microstructural characteristics were systematically investigated. Results show a consistent reduction in density and compressive strength with elevating the proportion of MSWI-BA. The compressive strength declined at all ages with higher MSWI-BA levels, showing a 28.49 % loss at 30 % replacement after 28 days. At early age (3 days), the mortar incorporating 10 % MSWI-BA exhibited a modest reduction in flexural performance (13.83 %). However, by 28 days, this mixture surpassed the control matrix with an 8.15 % improvement, reflecting the delayed benefits associated with BA incorporation. In contrast, higher replacement levels (20–30 %) resulted in flexural strength reductions of up to 37 %. Overall, up to 10 % MSWI-BA replacement is optimal for balancing performance and sustainability. Incorporating up to 10 % MSWI-BA as a partial cement replacement supports sustainable construction and circular economy practices without significantly affecting material performance.

由于传统水泥生产的高碳排放和资源消耗，建筑行业面临着与可持续性相关的重大问题。此外，城市生活垃圾焚烧底灰的处理存在环境风险。本研究考察了MSWI-BA在胶凝复合配方中部分替代水泥的潜力，特别强调了其对强度和微观结构的影响。该研究旨在促进资源回收，减少垃圾填埋场的使用，降低碳排放，促进生态友好的建筑解决方案和有效的废物利用。在0 %、10 %、20 %和30 %的取代水平上，用MSWI-BA部分替代水泥，系统地研究了对密度、孔隙率、吸水率、抗压强度、抗弯强度和微观结构特征的影响。结果表明，随着MSWI-BA比例的增加，密度和抗压强度呈一致的下降趋势。随着MSWI-BA水平的升高，抗压强度在所有年龄段都有所下降，在28天后更换30 %时，抗压强度下降28.49 %。在早期（3天），含有10 % MSWI-BA的砂浆显示出适度的弯曲性能降低（13.83 %）。然而，到了28天，这种混合物超过了对照基质，改善了8.15 %，反映了与BA掺入相关的延迟效益。相比之下，较高的置换水平（20-30 %）导致弯曲强度降低高达37 %。总体而言，高达10 %的MSWI-BA更换是平衡性能和可持续性的最佳选择。将高达10% %的MSWI-BA作为部分水泥替代品，支持可持续建筑和循环经济实践，而不会显著影响材料性能。

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引用次数: 0