Construction and Building Materials最新文献

{"title":"The mechanism of accelerator types on calcium leaching in shotcrete","authors":"Ziwei Zhang ,&nbsp;Mengdie Niu ,&nbsp;Zhentao Liu ,&nbsp;Guoxin Li","doi":"10.1016/j.conbuildmat.2024.139353","DOIUrl":"10.1016/j.conbuildmat.2024.139353","url":null,"abstract":"<div><div>In regions characterized by abundant water, the surrounding rock exhibits a high water content, which leads to calcium leaching in the shotcrete of the tunnel. This poses a significant hazard to the safe operation of the tunnel. The experimental design focuses on three commonly used accelerators in the market and investigates the leaching process of samples under accelerated leaching conditions. By integrating XRD, TG, and SEM-EDS testing, the calcium leaching mechanism of shotcrete was elucidated. Results revealed that sodium aluminate-based liquid accelerator exhibits the highest detrimental effect on mortar resistance against calcium leaching, followed by fluoroaluminic acid-based liquid accelerator. Additionally, an appropriate amount of aluminum sulfate-based liquid accelerator can effectively mitigate performance degradation during leaching processes in shotcrete. The addition of aluminum sulfate reduces CH content and C-S-H Ca/Si ratio of hydration products, leading to wrapping AFt generated by cement hydration with C-S-H and thereby slowing down solid calcium-containing substance dissolution in hydration products. A moderate accelerator can enhance shotcrete porosity so that corrosive products like CaCl₂ accumulate in existing pores first, reducing shotcrete performance deterioration rate.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"457 ","pages":"Article 139353"},"PeriodicalIF":7.4,"publicationDate":"2024-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745463","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experimental study on the high temperature performance of UHPCFST stub columns at different concrete age","authors":"Zhonghui Wang ,&nbsp;Min Yu ,&nbsp;Tan Wang ,&nbsp;Zewen Sun ,&nbsp;Jianqiao Ye","doi":"10.1016/j.conbuildmat.2024.139232","DOIUrl":"10.1016/j.conbuildmat.2024.139232","url":null,"abstract":"<div><div>Fire is one of the serious incidents occurring in the construction phase of Ultra-High Performance Concrete filled steel tubes (UHPCFST) columns, which may cause damage to materials, delays to construction and risk to life. This paper investigates the high temperature performance of UHPCFST columns at different concrete ages to simulate the occurrence of fire at construction phase. Axial compression experiments on 24 stub columns are conducted to investigate the effect of temperature levels, age of UHPC on the mechanical response of the UHPCFST columns at different construction stages. The findings reveal that the bearing capacity of the UHPCFST stub columns shows an increase and then a decrease with rising temperatures, and columns of earlier age exhibit a greater increase in fire-resistance bearing capacity. Notably, the load-bearing capacity at room temperature increase with the age of UHPC. At 300 ℃, a marginal increment in capacity correlating with age is observed, whereas at 700 ℃, there is a slight decline. Furthermore, the incorporation of coarse aggregate substantially contributes to the augmentation of load-bearing capabilities across diverse conditions. Meanwhile, a formula for calculating the load bearing capacity and equivalent stress-strain curve of UHPCFST stub columns under elevated temperature at different concrete ages is proposed and validated. This research is expected to provide valuable insights for assessing fire safety and reliability of UHPCFST structure in construction settings.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"457 ","pages":"Article 139232"},"PeriodicalIF":7.4,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745371","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Durability of Basalt fiber-reinforced aeolian sand concrete in extreme environments: Resistance to wind-sand erosion and salt freeze-thaw cycles","authors":"Yu Ye,&nbsp;Tianyu Xie,&nbsp;Tong Guo,&nbsp;Wei Ding","doi":"10.1016/j.conbuildmat.2024.139264","DOIUrl":"10.1016/j.conbuildmat.2024.139264","url":null,"abstract":"<div><div>This study investigates the mechanical properties and durability of basalt fiber aeolian sand concrete (BF-ASC) under wind-sand erosion (WSE) and salt freeze-thaw cycles (SFTC). The research explores the individual and combined effects of basalt fiber (BF) content (0.10 %, 0.15 %, 0.20 %) and aeolian sand (AS) substitution ratios (20 % and 100 %) on concrete properties. Mechanical tests include compressive, splitting tensile, and flexural strength, while durability tests focus on WSE and SFTC resistance. Base on the experimental results, several major findings are undisclosed. It is found that concrete with 20 % AS replacement and 0.15–0.20 % BF content significantly exhibits enhanced mechanical- and durability- related properties. A three-dimensional blue light scanning technique effectively quantifies the surface damage of AS concrete after WSE, demonstrating that 20 % AS based concrete has the least surface porosity and higher stability in surface roughness post-erosion, while 100 % AS concrete shows severe erosion effects, including mortar detachment and increased pitting. Moreover, the characterizations at the microstructural level demonstrates that a content AS incorporation (20 %) improves internal structure and hence the SFTC durability, with less pores and cracks compared to the companion conventional concrete. This research contributes vital insights into BF-ASC behavior under extreme conditions, offering guidance for optimal mix designs in harsh environments. The findings have significant implications for sustainable construction practices, particularly in regions facing challenges of desert sand utilization and severe environmental conditions.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"457 ","pages":"Article 139264"},"PeriodicalIF":7.4,"publicationDate":"2024-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142745372","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"A friction energy-based damage model for discrete element simulation of fatigue damage evolution in concrete","authors":"Pei Zhang ,&nbsp;Chao Liu ,&nbsp;Yang Liu ,&nbsp;Xin Gu","doi":"10.1016/j.conbuildmat.2024.139225","DOIUrl":"10.1016/j.conbuildmat.2024.139225","url":null,"abstract":"<div><div>The discrete results of concrete fatigue tests limit the research of concrete fatigue theory. Numerical simulation methods can model the damage of materials from multiple scales, which helps to reveal the fatigue damage mechanism and compensate for the inadequacy of physical tests. This study presents a novel damage model for simulating the fatigue damage evolution of cementitious materials within the framework of discrete element methods. The proposed friction energy-based fatigue damage model is underpinned by a clear fatigue damage mechanism and has only two independent parameters. The model underwent validation through a comparison between its predictions and the results of compression cycle tests performed on concrete specimens. The model reproduces the evolution characteristics of various fatigue damage indicators, including deformation, modulus, hysteretic energy, and number of cracks, and the fatigue damage accumulation rate presents sensitivity to the stress level. Furthermore, the model predicts a clear regularity in the fatigue damage thresholds, which is an important reference value for establishing fatigue failure criteria. The model can be used to predict fatigue life of fatigue tests with various maximum and minimum stress levels and the S-N curves obtained from the simulations fall within the range of test results.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"456 ","pages":"Article 139225"},"PeriodicalIF":7.4,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743029","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Mechanical strength, hydration products, and microstructure of waste-derived composite-activated cementitious materials by varying titanium gypsum phase composition","authors":"Ning Chang ,&nbsp;Hui Li ,&nbsp;Wenhuan Liu ,&nbsp;Xiaoyu Jiao ,&nbsp;Wukui Zheng ,&nbsp;Ziwei Yan ,&nbsp;Wenbin Yuan ,&nbsp;Zhou Zhou ,&nbsp;Qulang Mai ,&nbsp;Lu Zhang ,&nbsp;Xingzi Wu","doi":"10.1016/j.conbuildmat.2024.139328","DOIUrl":"10.1016/j.conbuildmat.2024.139328","url":null,"abstract":"<div><div>The high carbon footprint of commercial chemical activators has hindered the industrial application of alkali-activated cementitious materials as a substitute for Portland cement, leading to substantial pollution and carbon emissions. This study aims to investigate the effect of the Titanium Gypsum (TiG) phase composition on the mechanical strength, hydration products, and microstructure of Red Mud (RM)-Granulated Blast Furnace Slag (GBFS)-based waste-derived composite-activated cementitious Materials (GRGM). The properties were characterized through flexural and compressive strength measurements, XRD, FTIR, TG-DTG, MIP, and SEM-EDS. The results revealed that GRGM mortars, prepared by combining dihydrate gypsum and hemihydrate gypsum in specific proportions as a waste-derived sulphate activator, exhibited flexural and compressive strengths of 8.9 MPa and 56.5 MPa at 28 d, respectively. It was observed that the presence of hemihydrate gypsum played a crucial role in promoting the transformation of C(N)-A-S-H gel to C-S-H gel, enhancing the growth of ettringite and influencing its degree of polymerization. A hemihydrate gypsum content of at least 15 % significantly accelerated this transformation process, resulting in a broader range of hydration products. This diversification ultimately led to the densification of the pore structure in GRGM paste, thereby improving the mechanical strength of the specimens. Additionally, a hemihydrate gypsum content of less than 15 % resulted in a significant reduction in mechanical strength. Furthermore, the production energy consumption of GRGM was calculated to be 89.388 MJ/t, much lower than the energy consumption and carbon emissions typically associated with cement manufacturing. This paper elucidates the mechanisms by which various single-phase and double-phase waste-derived sulphate activators influence several critical physicochemical properties of waste-derived composite-activated cementitious materials. The study further explores the potential of TiG as a waste-derived activator for the design of waste-derived composite-activated cementitious materials, thereby strengthening the theoretical framework supporting their applications.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"456 ","pages":"Article 139328"},"PeriodicalIF":7.4,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743028","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Deep generative modelling for nonlinear analysis and in-situ assessment of masonry using multiple mechanical fields","authors":"Ahmad Adaileh ,&nbsp;Bahman Ghiassi ,&nbsp;Riccardo Briganti","doi":"10.1016/j.conbuildmat.2024.138745","DOIUrl":"10.1016/j.conbuildmat.2024.138745","url":null,"abstract":"<div><div>Design and in-situ assessment of masonry structures is a challenging task due to the brittle and nonlinear nature of this widely used material, the complex interaction between its components, and the vast variability of material properties in its design space. Current methodologies often rely on oversimplified assumptions that inadequately capture the true mechanical behaviour of masonry or require extensive knowledge and expertise for reliable implementation or interpretation of the obtained results. To overcome these limitations, this article presents an innovative generative machine learning approach, based on conditional generative adversarial network (cGAN), that allows establishing a direct or reverse link between masonry meso-structure and multiple mechanical fields without any specific knowledge of the properties or constitutive laws. The developed cGAN model interprets relationships among multiple mechanical maps using a single model, which leads to enhanced predictions in both linear and nonlinear stages for a wide range of unseen scenarios. The model shows an excellent capability to capture the effect of local and global variability of material properties, constituents sizes, and loading scenarios on the results in both direct (i.e. predicting the strain maps from meso-structure and material properties) and reverse (i.e. predicting the meso-structure and material properties from strain maps) problems. The proposed cGAN modelling approach emerges as a versatile tool with potential broad applications for the design and evaluation of nonlinear composite materials and mechanical behaviour of materials in general, addressing a wide spectrum of engineering challenges.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"456 ","pages":"Article 138745"},"PeriodicalIF":7.4,"publicationDate":"2024-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743143","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Influence of interface transition zones (ITZ) and pore structure on the compressive strength of recycled aggregate concrete","authors":"Chenggong Lu ,&nbsp;Qijun Yu ,&nbsp;Jiangxiong Wei ,&nbsp;Yanfei Niu ,&nbsp;Yafang Zhang ,&nbsp;Chun Lin ,&nbsp;Peixin Chen ,&nbsp;Chuan Shi ,&nbsp;Pengfei Yang","doi":"10.1016/j.conbuildmat.2024.139299","DOIUrl":"10.1016/j.conbuildmat.2024.139299","url":null,"abstract":"<div><div>This study aims to clarify the influence of interfacial transition zones (ITZs) and pore structure on the compressive strength of the recycled aggregate concrete (RAC). The compressive strength of the RAC are evaluated with the change of five different replacement ratios (10 %, 20 %, 30 %, 40 % and 50 %) and four various of particle sizes (5–10 mm, 10–16 mm, 16–20 mm and 20–25 mm) of the recycled coarse aggregate (RCA), the evolution process of crack propagation behavior have been accurately characterized, and the ITZs and pore structure of the RAC are analyzed. The results showed that the RAC incorporated 30 % RCA with particle size of 10–16 mm exhibited the maximum compressive strength, crack area and fractal dimension. There is a new interfacial transition zone (ITZ₂) with an average elastic modulus and microhardness of about 15 GPa and 1 GPa respectively between RCA and new matrix, which deteriorates the homogeneity inside RAC; As the particle size of recycled aggregate increases, the width of ITZ₂ first increases and then decreases. When the particle size of aggregate is 10–16 mm, the width of ITZ₂ reaches the maximum of 50μm. Compared with ITZ₂, the old interfacial transition zones (recycled aggregate-bonded mortar, ITZ₃, new mortar-bonded mortar, ITZ₄) have weaker mechanical properties, larger widths, and more obvious interface effects. Under uniaxial compression load, the old ITZs (ITZ₃ and ITZ₄) are an important factor affecting the performance and crack development of RAC. Taking the harmful pore structure of adhered mortar phase, new mortar phase, and ITZs phase as independent variables and the compressive strength of RAC as the dependent variable, a multiple linear regression model is established; through the analysis of the regression model, it is found that the ITZs are the main factor affecting the compressive strength of RAC.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"456 ","pages":"Article 139299"},"PeriodicalIF":7.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743213","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Development of a thermoplastic constitutive model for steel based on the generalized Mises yield criterion","authors":"Shuobiao Li ,&nbsp;Zhen Wang ,&nbsp;Wenqi Ding ,&nbsp;Qingzhao Zhang ,&nbsp;Linlin Gu","doi":"10.1016/j.conbuildmat.2024.139275","DOIUrl":"10.1016/j.conbuildmat.2024.139275","url":null,"abstract":"<div><div>Steel is widely used in building structures, and the constitutive model that describes the steel's response to load is an essential component of structural mechanics analysis. This paper aims to investigate the thermoplastic behavior of steel at elevated temperatures. Based on the classical elastoplastic mechanics framework, this study introduces a generalized Mises yield criterion derived from energy theory, which takes into account the temperature effect. In conjunction with relevant assumptions, hardening condition, flow rule, the generalized Hooke's law, and consistency condition, we derive a novel incremental thermoplastic constitutive model for steel. And the new thermoplastic constitutive model's rationality is further verified by utilizing high-temperature steady-state tensile test data. It is encouraging that this new model can accurately describe the mechanical behavior of steel in high-temperature environment such as fire, which is of significant importance for fire safety design of building structures.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"456 ","pages":"Article 139275"},"PeriodicalIF":7.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743314","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Bio-colonisation, durability, and microstructural analysis of concrete incorporating magnetite and oyster shell waste aggregates in marine environment","authors":"Mohammed Zelloufi ,&nbsp;Violeta Ramos ,&nbsp;Badreddine El Haddaji ,&nbsp;Amel Bourguiba ,&nbsp;Gavyn K. Rollinson ,&nbsp;Jens Andersen ,&nbsp;Nassim Sebaibi ,&nbsp;Mohamed Boutouil","doi":"10.1016/j.conbuildmat.2024.139269","DOIUrl":"10.1016/j.conbuildmat.2024.139269","url":null,"abstract":"<div><div>This study evaluates the impact of bio-colonisation and seawater attack on the durability, microstructure and mineralogy of two distinct concrete formulations. These formulations are designed to meet the specifications of marine infrastructure applications, particularly those intended as biomimetic solutions for infrastructures typically used for boat anchoring, which are commonly responsible for the displacement and destruction of marine habitats. The first formulation incorporates magnetite aggregates, resulting in a heavy concrete capable of stabilising the base structure of the biomimetic concrete mooring. In the second formulation, natural gravel is partially substituted by oyster shell waste, to reduce the carbon footprint of these marine infrastructures. Experimental tests were conducted to evaluate the bio-colonisation and durability of the two concrete formulations under marine exposure. After 24 months of immersion, the surface biomass on both formulations exhibited similar kinetic bio-receptivity, primarily attributed to the binder and surface roughness rather than the type of aggregates used. The porosity accessible to water decreases in marine conditions, suggesting that the biofilm contributes to this decrease. Durability results indicate that while both concrete types deteriorate under seawater exposure, the oyster shell aggregates demonstrated better resilience to natural seawater aggressiveness compared to magnetite aggregates over long-term exposure. Elemental mapping showed no obvious zonation of elements. However, a slight increase in surface roughness was observed, with no macroscopic damage detected. This research enhances our understanding of how magnetite and oyster shell waste aggregates respond to bio-colonisation and seawater attack, which are critical factors in the development of biomimetic marine infrastructure.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"456 ","pages":"Article 139269"},"PeriodicalIF":7.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743315","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of CO2 curing on the resistance of calcium sulfoaluminate cement paste to elevated temperature","authors":"Xuanru Wu ,&nbsp;Raju Sharma ,&nbsp;Kunal Krishna Das ,&nbsp;Jiwhan Ahn ,&nbsp;Jeong Gook Jang","doi":"10.1016/j.conbuildmat.2024.139338","DOIUrl":"10.1016/j.conbuildmat.2024.139338","url":null,"abstract":"<div><div>This study investigates the effect of CO₂ curing on the resistance to elevated temperatures of calcium sulfoaluminate (CSA) cement paste. Water and CO₂-cured CSA cement paste specimens were exposed to elevated temperatures of 150 °C, 300 °C, 500 °C, and 800 °C to evaluate their physicochemical and mechanical properties. The results demonstrate that CO₂ infiltration alters the hydration mechanism of CSA cement, consequently enhancing its physical properties and thermal stability. Exposure to elevated temperatures induces changes in color and the formation of cracks in cement paste samples, with water-cured samples exhibiting more prominent cracks compared to CO₂-cured samples. CO₂-cured samples demonstrate less of a reduction in the compressive strength at high temperatures compared to water-cured samples, an outcome attributed to the enhanced stability and uniform pore size distribution. In conclusion, the CO₂ curing process transforms ettringite and monosulfate into thermally stable calcium carbonate, which significantly enhances the thermal stability of the cement paste.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"456 ","pages":"Article 139338"},"PeriodicalIF":7.4,"publicationDate":"2024-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142743321","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}