Pub Date : 2024-11-15DOI: 10.1016/j.conbuildmat.2024.139081
Bei Zhang , Xiang Wang , Longting Ding , Quansheng Zang , Bori Cong , Hongjian Cai , Tairan Liu , Yanhui Zhong
Ground Penetrating Radar (GPR) is widely utilized in detecting subsurface distress. However, its identification and analysis still face challenges. We propose a method based on the Generative Adversarial Network (GAN) to process GPR B-scan data containing semi-rigid base loose distress. An end-to-end GAN invert GPR B-scan into cross-sectional images of the road. A U-net is used in the generator to transform from GPR B-scan to road loose models. A patchGAN is used in the discriminator to determine the correlation between the GPR B-scan and road loose models. We used Finite-Difference Time-Domain (FDTD) and random mediums to construct the road loose distress model. Based on this model, the simulated dataset of 14,000 sets of images was randomly generated. Post-processing of the simulated dataset generated the synthetic dataset of 14,000 sets of images. The identification results trained on the simulated dataset and synthetic dataset achieved 90 % and 97 % average Structural Similarity Index (SSIM) compared to the source images. Through threshold segmentation of the generated images, 3D models are reconstructed using Marching Cubes (MC). Validation with the actual project indicates that this method effectively recognizes loose distress, and the generated 3D distribution model accurately represents the road condition. This approach offers a promising solution to the challenge of radar image identification and introduces a new data inversion method for road nondestructive testing.
{"title":"Identification and 3D reconstruction of semi-rigid base loose distress from GPR B-scan using Generative Adversarial Network","authors":"Bei Zhang , Xiang Wang , Longting Ding , Quansheng Zang , Bori Cong , Hongjian Cai , Tairan Liu , Yanhui Zhong","doi":"10.1016/j.conbuildmat.2024.139081","DOIUrl":"10.1016/j.conbuildmat.2024.139081","url":null,"abstract":"<div><div>Ground Penetrating Radar (GPR) is widely utilized in detecting subsurface distress. However, its identification and analysis still face challenges. We propose a method based on the Generative Adversarial Network (GAN) to process GPR B-scan data containing semi-rigid base loose distress. An end-to-end GAN invert GPR B-scan into cross-sectional images of the road. A U-net is used in the generator to transform from GPR B-scan to road loose models. A patchGAN is used in the discriminator to determine the correlation between the GPR B-scan and road loose models. We used Finite-Difference Time-Domain (FDTD) and random mediums to construct the road loose distress model. Based on this model, the simulated dataset of 14,000 sets of images was randomly generated. Post-processing of the simulated dataset generated the synthetic dataset of 14,000 sets of images. The identification results trained on the simulated dataset and synthetic dataset achieved 90 % and 97 % average Structural Similarity Index (SSIM) compared to the source images. Through threshold segmentation of the generated images, 3D models are reconstructed using Marching Cubes (MC). Validation with the actual project indicates that this method effectively recognizes loose distress, and the generated 3D distribution model accurately represents the road condition. This approach offers a promising solution to the challenge of radar image identification and introduces a new data inversion method for road nondestructive testing.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139081"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663834","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}
Pub Date : 2024-11-15DOI: 10.1016/j.conbuildmat.2024.139160
Lijie Chen , Kun Liang , Ray Kai Leung Su , Zhenyu Huang
The mechanical performance of basalt fiber reinforced polymer (BFRP) bars can deteriorate as a result of creep rupture due to sustained loading and alkaline corrosion caused by concrete alkalinity. Unfortunately, the effect of alkaline corrosion on the creep rupture performance of BFRP bars remains unclear. This study aims to investigate the effects of the pH value and temperature of the simulated pore solution of supplementary cementitious material (SCM) seawater sea sand concrete (SWSSC) subject to carbonation, on the creep rupture of BFRP bars. The pH value, chemical composition of pore solution, phase composition and pore structure of SCM concrete subject to natural carbonation have been characterized. The creep rupture performance of BFRP bars in simulated pore solutions have been tested at various pH values (9.0, 11.0 and 13.5) and temperatures (25 °C, 45 °C and 65 °C). A theoretical model for predicting the creep rupture strength of BFRP bars in air, simulated pore solution and real concrete environments has been developed and validated in comparison with experimental data in existing literature. Experimental results suggest that reducing the pH value (down to 10–11) and temperature of the pore solution can significantly improve the creep rupture performance of BFRP bars. The application of limestone calcined clay cement (LC3) concrete and concrete carbonation is promising in mitigating the alkaline corrosion effect on the creep rupture performance of BFRP bars by lowering pH values, as evidenced by the improvements of creep rupture strength at one million hours of OPC concrete, from 24.1 % to 50.3 % and 71.2 %, respectively.
{"title":"Effects of pH value and temperature in pore solution of carbonated SCM concrete on creep rupture performance of BFRP bars","authors":"Lijie Chen , Kun Liang , Ray Kai Leung Su , Zhenyu Huang","doi":"10.1016/j.conbuildmat.2024.139160","DOIUrl":"10.1016/j.conbuildmat.2024.139160","url":null,"abstract":"<div><div>The mechanical performance of basalt fiber reinforced polymer (BFRP) bars can deteriorate as a result of creep rupture due to sustained loading and alkaline corrosion caused by concrete alkalinity. Unfortunately, the effect of alkaline corrosion on the creep rupture performance of BFRP bars remains unclear. This study aims to investigate the effects of the pH value and temperature of the simulated pore solution of supplementary cementitious material (SCM) seawater sea sand concrete (SWSSC) subject to carbonation, on the creep rupture of BFRP bars. The pH value, chemical composition of pore solution, phase composition and pore structure of SCM concrete subject to natural carbonation have been characterized. The creep rupture performance of BFRP bars in simulated pore solutions have been tested at various pH values (9.0, 11.0 and 13.5) and temperatures (25 °C, 45 °C and 65 °C). A theoretical model for predicting the creep rupture strength of BFRP bars in air, simulated pore solution and real concrete environments has been developed and validated in comparison with experimental data in existing literature. Experimental results suggest that reducing the pH value (down to 10–11) and temperature of the pore solution can significantly improve the creep rupture performance of BFRP bars. The application of limestone calcined clay cement (LC<sup>3</sup>) concrete and concrete carbonation is promising in mitigating the alkaline corrosion effect on the creep rupture performance of BFRP bars by lowering pH values, as evidenced by the improvements of creep rupture strength at one million hours of OPC concrete, from 24.1 % to 50.3 % and 71.2 %, respectively.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139160"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663827","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}
Pub Date : 2024-11-15DOI: 10.1016/j.conbuildmat.2024.139137
Zheng Chen , Guoxin Zhao , Ben Chen , Shengzhao Chen , Jing Li , Yumei Nong
The time-varying evolution of the flocculation structure of cement paste is the fundamental cause of fluidity loss and rheological property degradation. To quantitatively analyze these time-dependent behaviors, the flocculation structure, fluidity, rheological property, and hydration heat of cement paste affected by different factors were tested and analyzed in this study. In addition, the correlations between the mesoscopic flocculation structure and the macroscopic fluidity, rheological property of cement paste were quantitatively analyzed based on fractal theory. Results reveal that a larger fractal dimension corresponds to a smaller size and greater dispersion of the flocculation structure, while a smaller fractal dimension corresponds to a larger size and higher compactness of the flocculation structure. As time progresses, the fractal dimension decreases, indicating a larger flocculation structure size and reduced self-similarity. The fractal dimension curve and the fluidity curve show similar trends, with a positive correlation between fluidity and the fractal dimension of the flocculation structure. In contrast, the fractal dimension curve and the rheological parameter curve exhibit opposite trends, indicating a negative correlation between rheological parameters and the fractal dimension of the flocculation structure. The water-cement ratio and PCE content significantly affect the initial flocculation structure size, while the addition of a retarder brings no impact. A higher water-cement ratio and PCE content result in a larger fractal dimension. Based on the hydration degree of cement and the dispersing mechanism of PCE, and considering the relation between fluidity and fractal dimension, an analytical model was established for the time-dependent fluidity of cement paste. Additionally, using the YODEL model and the Krieger-Dougherty model, and considering the relation between yield stress, plastic viscosity of cement paste and fractal dimension of flocculation structure, analytical models were developed for the rheological property of cement paste. The study established functional analytical models between the mesoscopic flocculation structure and the macroscopic fluidity, rheological property of cement paste, providing essential guidance for controlling the fluidity and rheological property of cement-based materials.
{"title":"Influence of flocculation structure on time-dependent fluidity and rheological property of cement paste: Analytical models based on fractal theory","authors":"Zheng Chen , Guoxin Zhao , Ben Chen , Shengzhao Chen , Jing Li , Yumei Nong","doi":"10.1016/j.conbuildmat.2024.139137","DOIUrl":"10.1016/j.conbuildmat.2024.139137","url":null,"abstract":"<div><div>The time-varying evolution of the flocculation structure of cement paste is the fundamental cause of fluidity loss and rheological property degradation. To quantitatively analyze these time-dependent behaviors, the flocculation structure, fluidity, rheological property, and hydration heat of cement paste affected by different factors were tested and analyzed in this study. In addition, the correlations between the mesoscopic flocculation structure and the macroscopic fluidity, rheological property of cement paste were quantitatively analyzed based on fractal theory. Results reveal that a larger fractal dimension corresponds to a smaller size and greater dispersion of the flocculation structure, while a smaller fractal dimension corresponds to a larger size and higher compactness of the flocculation structure. As time progresses, the fractal dimension decreases, indicating a larger flocculation structure size and reduced self-similarity. The fractal dimension curve and the fluidity curve show similar trends, with a positive correlation between fluidity and the fractal dimension of the flocculation structure. In contrast, the fractal dimension curve and the rheological parameter curve exhibit opposite trends, indicating a negative correlation between rheological parameters and the fractal dimension of the flocculation structure. The water-cement ratio and PCE content significantly affect the initial flocculation structure size, while the addition of a retarder brings no impact. A higher water-cement ratio and PCE content result in a larger fractal dimension. Based on the hydration degree of cement and the dispersing mechanism of PCE, and considering the relation between fluidity and fractal dimension, an analytical model was established for the time-dependent fluidity of cement paste. Additionally, using the YODEL model and the Krieger-Dougherty model, and considering the relation between yield stress, plastic viscosity of cement paste and fractal dimension of flocculation structure, analytical models were developed for the rheological property of cement paste. The study established functional analytical models between the mesoscopic flocculation structure and the macroscopic fluidity, rheological property of cement paste, providing essential guidance for controlling the fluidity and rheological property of cement-based materials.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139137"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663830","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}
Pub Date : 2024-11-15DOI: 10.1016/j.conbuildmat.2024.139076
Ya’nan Cui , Kun Geng , Qiaoyan Zhou , Shuyan Zhang
<div><div>In view of the shifting focus of highway development in China from construction to maintenance, a substantial amount of Recycled Asphalt Pavement (RAP) materials is generated every year. Therefore, the recycling technology for asphalt pavements and methods to enhance the utilization rate of RAP materials have become focal points of academic research and engineering practice. The adhesion between asphalt and aggregates is crucial for the strength and durability of asphalt pavements. Given the complex composition of warm mix recycled asphalt and the unclear interactions with aggregates, it is of great practical significance to evaluate the applicability of warm mix recycled asphalt by exploring the adhesion between warm mix recycled asphalt and aggregate. To analyze the adhesion properties of warm mix recycled asphalt, this study employs Atomic Force Microscopy (AFM), contact angle tests, and pull-out tests to examine the effects of aged asphalt content, regeneration agents, warm mix agents, and various types of aggregates on the interfacial adhesion between asphalt and aggregates at both macro and micro scales. The results indicate that the incorporation of warm mix agents and regeneration agents can mitigate the negative impact of aged asphalt content on adhesion force. Specifically, when the aged asphalt proportion reaches 60 %, the adhesion force of warm mix recycled asphalt only decreases by 12.2 %. Moreover, the microstructural morphology of warm mix recycled asphalt is the closest to that of the original asphalt. The interfacial failure energy between asphalt and aggregates decreases with increasing proportions of aged asphalt. The adhesion of granite to asphalt is significantly affected by the aged asphalt content, while limestone exhibits lesser sensitivity to such changes. The addition of warm mix agents and regeneration agents contributes to an increase in the interfacial failure energy between asphalt and aggregates, with warm mix recycled asphalt displaying the highest interfacial failure energy. Aging not only weakens the cohesion work of asphalt but also reduces the adhesion work between asphalt and aggregates. As the aged asphalt proportion increases from 15 % to 60 %, the strongest adhesion work occurs under the synergistic action of warm mix agents and regeneration agents. Both contact angle tests and pull-out tests show that the adhesion performance of various aggregates with asphalt follows the order: limestone > basalt > granite. Correlation analysis reveals a robust relationship between macro and micro indicators, enabling an effective evaluation of the adhesion between warm mix recycled asphalt and aggregates. Overall, these experimental results demonstrate that warm mix recycling is an effective method that reduces the adverse effects of increasing aged asphalt content on adhesion performance, ensuring compatibility between asphalt and aggregates, and facilitating successful engineering implementation.</div><
{"title":"Research on the adhesion between warm mix recycled asphalt and aggregates at macro and micro scales","authors":"Ya’nan Cui , Kun Geng , Qiaoyan Zhou , Shuyan Zhang","doi":"10.1016/j.conbuildmat.2024.139076","DOIUrl":"10.1016/j.conbuildmat.2024.139076","url":null,"abstract":"<div><div>In view of the shifting focus of highway development in China from construction to maintenance, a substantial amount of Recycled Asphalt Pavement (RAP) materials is generated every year. Therefore, the recycling technology for asphalt pavements and methods to enhance the utilization rate of RAP materials have become focal points of academic research and engineering practice. The adhesion between asphalt and aggregates is crucial for the strength and durability of asphalt pavements. Given the complex composition of warm mix recycled asphalt and the unclear interactions with aggregates, it is of great practical significance to evaluate the applicability of warm mix recycled asphalt by exploring the adhesion between warm mix recycled asphalt and aggregate. To analyze the adhesion properties of warm mix recycled asphalt, this study employs Atomic Force Microscopy (AFM), contact angle tests, and pull-out tests to examine the effects of aged asphalt content, regeneration agents, warm mix agents, and various types of aggregates on the interfacial adhesion between asphalt and aggregates at both macro and micro scales. The results indicate that the incorporation of warm mix agents and regeneration agents can mitigate the negative impact of aged asphalt content on adhesion force. Specifically, when the aged asphalt proportion reaches 60 %, the adhesion force of warm mix recycled asphalt only decreases by 12.2 %. Moreover, the microstructural morphology of warm mix recycled asphalt is the closest to that of the original asphalt. The interfacial failure energy between asphalt and aggregates decreases with increasing proportions of aged asphalt. The adhesion of granite to asphalt is significantly affected by the aged asphalt content, while limestone exhibits lesser sensitivity to such changes. The addition of warm mix agents and regeneration agents contributes to an increase in the interfacial failure energy between asphalt and aggregates, with warm mix recycled asphalt displaying the highest interfacial failure energy. Aging not only weakens the cohesion work of asphalt but also reduces the adhesion work between asphalt and aggregates. As the aged asphalt proportion increases from 15 % to 60 %, the strongest adhesion work occurs under the synergistic action of warm mix agents and regeneration agents. Both contact angle tests and pull-out tests show that the adhesion performance of various aggregates with asphalt follows the order: limestone > basalt > granite. Correlation analysis reveals a robust relationship between macro and micro indicators, enabling an effective evaluation of the adhesion between warm mix recycled asphalt and aggregates. Overall, these experimental results demonstrate that warm mix recycling is an effective method that reduces the adverse effects of increasing aged asphalt content on adhesion performance, ensuring compatibility between asphalt and aggregates, and facilitating successful engineering implementation.</div><","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139076"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664191","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}
Pub Date : 2024-11-14DOI: 10.1016/j.conbuildmat.2024.139133
Ibrahim Wahab Adebayo , Guangcheng Long , Zhuo Tang , Mohammad Osman Ghone , Saifurahman Zaland , Mustapha Jamaa Garba , Kai Yang , Khalid Akhunzada , Usman Abdulfatai Oluwasina
Although geopolymer concrete has been regarded as an eco-friendly alternative to traditional concrete, it exhibits the same features of high brittleness or low ductility as traditional concrete. To address these challenges and promote sustainability, this study investigated the effects of crumb rubber (CR) and polyethylene (PE) fiber on the physical properties, strength, and toughness of fly ash/slag-based geopolymer concrete, in which CR produced from recycled rubber was replaced by natural sand at volume fractions of 5 %, 10 %, and 15 %, while PEF was added at volume fractions of 0.25 %, 0.5 %, and 0.75 %. The test results show that while the mechanical strength of CR specimens was low, their toughness and failure characteristics improved. PEF greatly enhanced the mechanical strength and toughness, which enhanced the failure mode. Notably, the synergistic impact of mixing CR and PEF produced better results than using these toughening materials separately, hybrid mix of 5 % CR and 0.75 % PEF were found to provide optimum toughness and moderate strength. These results were validated by microstructural analysis, highlighting the enhanced bonding with PEF and the negative impact of excessive CR on the concrete matrix.
{"title":"Effect of crumb rubber and polyethylene fiber on the strength and toughness of fly ash/slag-based geopolymer concrete","authors":"Ibrahim Wahab Adebayo , Guangcheng Long , Zhuo Tang , Mohammad Osman Ghone , Saifurahman Zaland , Mustapha Jamaa Garba , Kai Yang , Khalid Akhunzada , Usman Abdulfatai Oluwasina","doi":"10.1016/j.conbuildmat.2024.139133","DOIUrl":"10.1016/j.conbuildmat.2024.139133","url":null,"abstract":"<div><div>Although geopolymer concrete has been regarded as an eco-friendly alternative to traditional concrete, it exhibits the same features of high brittleness or low ductility as traditional concrete. To address these challenges and promote sustainability, this study investigated the effects of crumb rubber (CR) and polyethylene (PE) fiber on the physical properties, strength, and toughness of fly ash/slag-based geopolymer concrete, in which CR produced from recycled rubber was replaced by natural sand at volume fractions of 5 %, 10 %, and 15 %, while PEF was added at volume fractions of 0.25 %, 0.5 %, and 0.75 %. The test results show that while the mechanical strength of CR specimens was low, their toughness and failure characteristics improved. PEF greatly enhanced the mechanical strength and toughness, which enhanced the failure mode. Notably, the synergistic impact of mixing CR and PEF produced better results than using these toughening materials separately, hybrid mix of 5 % CR and 0.75 % PEF were found to provide optimum toughness and moderate strength. These results were validated by microstructural analysis, highlighting the enhanced bonding with PEF and the negative impact of excessive CR on the concrete matrix.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139133"},"PeriodicalIF":7.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664274","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}
Pub Date : 2024-11-14DOI: 10.1016/j.conbuildmat.2024.139130
Chuanxi Li , Bohai Ji , Yue Yao
Notch fatigue significantly challenges the structural integrity of notched components in engineering. This study improved traditional theory of critical distance (TCD) by refining its effective stress formula and critical distance model, while also incorporating Weibull distribution to develop probabilistic fatigue assessment frameworks. Subsequently, the feasibility of these frameworks was validated using fatigue test data from typical notched specimens made of Al2024-T351 and En3B materials. Based on this validation, P-S-N curves for typical notched details in steel bridges were estimated. The results show that the predicted P-S-N curves closely align with fatigue test data and have lower prediction errors than traditional TCD, which verifies the effectiveness of the proposed frameworks in evaluating typical notched details in steel bridges. Additionally, these P-S-N curves offer a potential for assessing the probabilistic fatigue life of similar notched details in steel bridges.
{"title":"Critical distance-based probabilistic fatigue analysis of base-material notches in steel bridges considering size effect","authors":"Chuanxi Li , Bohai Ji , Yue Yao","doi":"10.1016/j.conbuildmat.2024.139130","DOIUrl":"10.1016/j.conbuildmat.2024.139130","url":null,"abstract":"<div><div>Notch fatigue significantly challenges the structural integrity of notched components in engineering. This study improved traditional theory of critical distance (TCD) by refining its effective stress formula and critical distance model, while also incorporating Weibull distribution to develop probabilistic fatigue assessment frameworks. Subsequently, the feasibility of these frameworks was validated using fatigue test data from typical notched specimens made of Al2024-T351 and En3B materials. Based on this validation, <em>P-S-N</em> curves for typical notched details in steel bridges were estimated. The results show that the predicted <em>P-S-N</em> curves closely align with fatigue test data and have lower prediction errors than traditional TCD, which verifies the effectiveness of the proposed frameworks in evaluating typical notched details in steel bridges. Additionally, these <em>P-S-N</em> curves offer a potential for assessing the probabilistic fatigue life of similar notched details in steel bridges.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139130"},"PeriodicalIF":7.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664250","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}
Pub Date : 2024-11-14DOI: 10.1016/j.conbuildmat.2024.139132
Rihan Zhang , Tongcai Wang , Tingting Zhao , Gong Wang
Establishing lunar bases is pivotal for furthering lunar research and propelling deep space exploration. Lunar regolith based in-site construction is identified as the most feasible method for lunar structures. In addition, the reliance on Earth-Moon transportation, the energy required for lunar regolith manufacturing and the quality of the fabricated products are key factors in choosing a suitable forming method. This study proposes a novel way for in-site lunar regolith construction by utilizing a small amount of resin-based binding material and a combined processing method of molding and thermosetting. A specific thermosetting resin is developed to achieve fully solidification of the mixed material at lunar daytime temperatures of approximately 120 °C, addressing the high energy consumption associated with the sintering process. Mold pressing is used to provide the rapid pre-forming of mixed materials and greatly reduce the proportion of additives. The binder additions ranging from 5 wt% to 1 wt% were investigated. It was found that the formed part with a binder proportion of 2 wt% could achieve a compressive strength exceeding 26 MPa and the low thermal conductivity of about 0.371 W/(m·K). The proposed method has advantages of high in-situ utilization rate, low-energy consumption and rapid formation rate, enabling efficient forming of high performance lunar regolith structure and providing feasibility for future lunar construction projects.
{"title":"Rapid formation of high-performance lunar regolith composite via combined mold pressing and thermocuring processing with low content of resin-based additives","authors":"Rihan Zhang , Tongcai Wang , Tingting Zhao , Gong Wang","doi":"10.1016/j.conbuildmat.2024.139132","DOIUrl":"10.1016/j.conbuildmat.2024.139132","url":null,"abstract":"<div><div>Establishing lunar bases is pivotal for furthering lunar research and propelling deep space exploration. Lunar regolith based in-site construction is identified as the most feasible method for lunar structures. In addition, the reliance on Earth-Moon transportation, the energy required for lunar regolith manufacturing and the quality of the fabricated products are key factors in choosing a suitable forming method. This study proposes a novel way for in-site lunar regolith construction by utilizing a small amount of resin-based binding material and a combined processing method of molding and thermosetting. A specific thermosetting resin is developed to achieve fully solidification of the mixed material at lunar daytime temperatures of approximately 120 °C, addressing the high energy consumption associated with the sintering process. Mold pressing is used to provide the rapid pre-forming of mixed materials and greatly reduce the proportion of additives. The binder additions ranging from 5 wt% to 1 wt% were investigated. It was found that the formed part with a binder proportion of 2 wt% could achieve a compressive strength exceeding 26 MPa and the low thermal conductivity of about 0.371 W/(m·K). The proposed method has advantages of high in-situ utilization rate, low-energy consumption and rapid formation rate, enabling efficient forming of high performance lunar regolith structure and providing feasibility for future lunar construction projects.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139132"},"PeriodicalIF":7.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664273","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}
Pub Date : 2024-11-14DOI: 10.1016/j.conbuildmat.2024.139106
Henggen Zhang , Tao Liu , Yuxue Cui , Jianguo Zheng , Weihua Wang , Yanbin Li
Sandstone, a primary construction material for many renowned historical structures, may experience long-term stability degradation due to combined effects of fire and acidic hydrochemical environments. To effectively protect and restore these historical buildings, it is crucial to investigate the deterioration patterns and mechanisms of mechanical properties of sandstone under thermo-acid (t-a) coupling conditions. In this study, red sandstone specimens were subjected to coupled treatment of high temperatures (300°C and 600°C) and sulfuric acid (H2SO4) solutions at pH=2. Subsequently, the physical properties (including appearance, mass, P-wave velocity, and porosity) and mechanical properties (including static and dynamic compressive and tensile strengths) of the treated specimens were evaluated. Techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray computed tomography (CT) were utilized to investigate the mineralogy, microstructure, and crack propagation of specimens. The results revealed that the t-a coupling treatment led to a significant increase in mass loss and porosity, along with a decrease in P-wave velocity. Above the threshold temperature, high temperature became the dominant damage factor, and damage exhibited a distinct size effect. The static and dynamic mechanical properties of red sandstone decreased significantly after t-a coupling treatment, with the failure mode being more complex. After immersion in coupling with H2SO4 solution at 600°C, the amount of gypsum formed on the specimen surface decreased, and the static peak stress (σt) and dynamic peak stress (σd) decreased by 41.18 % and 26.21 %, respectively. High temperatures caused the connections between mineral particles to weaken, primarily affecting minerals other than feldspars, while immersion in H2SO4 solution initiated intense reactions between calcite, goethite, hematite, and chlorite with H+ ions. After t-a coupling treatment, the crack morphology became more intricate, with an increase in the three-dimensional (3D) crack volume.
{"title":"Experimental study on the deterioration mechanisms of physical and mechanical properties of red sandstone after thermal-acid coupling treatment","authors":"Henggen Zhang , Tao Liu , Yuxue Cui , Jianguo Zheng , Weihua Wang , Yanbin Li","doi":"10.1016/j.conbuildmat.2024.139106","DOIUrl":"10.1016/j.conbuildmat.2024.139106","url":null,"abstract":"<div><div>Sandstone, a primary construction material for many renowned historical structures, may experience long-term stability degradation due to combined effects of fire and acidic hydrochemical environments. To effectively protect and restore these historical buildings, it is crucial to investigate the deterioration patterns and mechanisms of mechanical properties of sandstone under thermo-acid (t-a) coupling conditions. In this study, red sandstone specimens were subjected to coupled treatment of high temperatures (300°C and 600°C) and sulfuric acid (H<sub>2</sub>SO<sub>4</sub>) solutions at pH=2. Subsequently, the physical properties (including appearance, mass, P-wave velocity, and porosity) and mechanical properties (including static and dynamic compressive and tensile strengths) of the treated specimens were evaluated. Techniques such as X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), and X-ray computed tomography (CT) were utilized to investigate the mineralogy, microstructure, and crack propagation of specimens. The results revealed that the t-a coupling treatment led to a significant increase in mass loss and porosity, along with a decrease in P-wave velocity. Above the threshold temperature, high temperature became the dominant damage factor, and damage exhibited a distinct size effect. The static and dynamic mechanical properties of red sandstone decreased significantly after t-a coupling treatment, with the failure mode being more complex. After immersion in coupling with H<sub>2</sub>SO<sub>4</sub> solution at 600°C, the amount of gypsum formed on the specimen surface decreased, and the static peak stress (<em>σ</em><sub>t</sub>) and dynamic peak stress (<em>σ</em><sub>d</sub>) decreased by 41.18 % and 26.21 %, respectively. High temperatures caused the connections between mineral particles to weaken, primarily affecting minerals other than feldspars, while immersion in H<sub>2</sub>SO<sub>4</sub> solution initiated intense reactions between calcite, goethite, hematite, and chlorite with H<sup>+</sup> ions. After t-a coupling treatment, the crack morphology became more intricate, with an increase in the three-dimensional (3D) crack volume.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139106"},"PeriodicalIF":7.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664248","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}
Pub Date : 2024-11-14DOI: 10.1016/j.conbuildmat.2024.139134
Weixiang Zhao , Wu Wen , Haoran Li , Jing Hu
In order to investigate the expansion of steel slag and improving the performance of steel slag asphalt mixtures, 5 %, 10 % and 15 % concentrations of acetic acid solution were used for the pretreatment of steel slag. Fundamental physical-mechanical properties of steel slag were assessed, and the chemical composition and microscopic morphology of acid-treated steel slag were examined using XRF, SEM, EDS, and XRD analyses. Furthermore, steel slag asphalt mixtures were prepared by substituting the acid-treated steel slag for basalt aggregates, and the high-temperature performance, low-temperature performance, volume stability, water resistance, and fatigue behavior of asphalt mixtures incorporating acid-treated steel slag were investigated. Additionally, The comprehensive three-dimensional analysis of the pore structure in acid-treated steel slag asphalt mixtures was conducted to show the fundamental connection between their microscopic and macroscopic properties. The results reveal that the acetic acid pretreatment decreases the levels of f-MgO and f-CaO in steel slag effectively, thereby reducing its expansion. Moreover, the surface roughening induced by acetic acid pretreatment significantly enhances adhesion between asphalt and the steel slag surface. Meanwhile, acetic acid treatment also enhances road performance of steel slag asphalt mixtures, particularly exemplified by A15-AM (15 % acid-treated steel slag asphalt mixture). Additionally, the pore structure of the acid-treated steel slag asphalt mixture was refined, leading to an improvement in its road performance.
{"title":"Research on the performance of asphalt mixture with acid-treated steel slag based on microscopic properties","authors":"Weixiang Zhao , Wu Wen , Haoran Li , Jing Hu","doi":"10.1016/j.conbuildmat.2024.139134","DOIUrl":"10.1016/j.conbuildmat.2024.139134","url":null,"abstract":"<div><div>In order to investigate the expansion of steel slag and improving the performance of steel slag asphalt mixtures, 5 %, 10 % and 15 % concentrations of acetic acid solution were used for the pretreatment of steel slag. Fundamental physical-mechanical properties of steel slag were assessed, and the chemical composition and microscopic morphology of acid-treated steel slag were examined using XRF, SEM, EDS, and XRD analyses. Furthermore, steel slag asphalt mixtures were prepared by substituting the acid-treated steel slag for basalt aggregates, and the high-temperature performance, low-temperature performance, volume stability, water resistance, and fatigue behavior of asphalt mixtures incorporating acid-treated steel slag were investigated. Additionally, The comprehensive three-dimensional analysis of the pore structure in acid-treated steel slag asphalt mixtures was conducted to show the fundamental connection between their microscopic and macroscopic properties. The results reveal that the acetic acid pretreatment decreases the levels of f-MgO and f-CaO in steel slag effectively, thereby reducing its expansion. Moreover, the surface roughening induced by acetic acid pretreatment significantly enhances adhesion between asphalt and the steel slag surface. Meanwhile, acetic acid treatment also enhances road performance of steel slag asphalt mixtures, particularly exemplified by A15-AM (15 % acid-treated steel slag asphalt mixture). Additionally, the pore structure of the acid-treated steel slag asphalt mixture was refined, leading to an improvement in its road performance.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139134"},"PeriodicalIF":7.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664246","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}
Pub Date : 2024-11-14DOI: 10.1016/j.conbuildmat.2024.139158
Fubin Zhang , Rujun Zheng , Gaoyu Liao , Dianchao Wang , Zhengyi Lu , Haining Meng , Zheng Lu
Self-compacting recycled concrete (SCC) has properties of significant shrinkage deformation and early cracking, which limits its wide application in civil engineering applications. Waste fiber addition offers an effective solution to these challenges. This research focuses on waste glass fiber and explored the impact of various parameters on the performance of recycled glass fiber-reinforced self-compacting recycled aggregate concrete (RGF-SCRC). Incorporating waste glass fiber effectively inhibits the long-term shrinkage rate of RGF-SCRC and improves its axial compressive strength, with the improvement of 2.2∼15.3 % in axial compressive strength and a reduction of 17.9∼66.5 % in the long-term shrinkage rate. However, excessive fiber addition shows an negatively effect on the performance of RGF-SCRC. The optimum addition was concluded as 7.5 kg/m³. On the other hand, the waste alkali-resistant glass fiber showed a higher improvement than waste glass fiber. Moreover, microstructure analysis reveals that the waste fibers could be uniformly dispersed within the investigated specimen, effectively bridging gaps and significantly enhancing the concrete’s strength and toughness. Furthermore, the number of large pores and overall porosity were reduced, resulting in greater compactness, improved axial compressive strength, and reduced long-term shrinkage of RGF-SCRC. After 180 days of curing, the porosity of the specimens significantly decreased when compared to the 28 day curing specimens. Based on experimental results, the axial compression stress-strain relationship and long-term shrinkage curves of RGF-SCRC were fitted and modified, and proposed an axial compression constitutive relationship and a long-term shrinkage theoretical analysis model which are applicable to RGF-SCRC. The models' correctness was verified by comparing them with experimental results. These research outcomes offer valuable insights for the future practical implementation of RGF-SCRC.
{"title":"Axial compressive and long-term shrinkage behaviors of self-compacting recycled concrete reinforced with recycled glass fiber","authors":"Fubin Zhang , Rujun Zheng , Gaoyu Liao , Dianchao Wang , Zhengyi Lu , Haining Meng , Zheng Lu","doi":"10.1016/j.conbuildmat.2024.139158","DOIUrl":"10.1016/j.conbuildmat.2024.139158","url":null,"abstract":"<div><div>Self-compacting recycled concrete (SCC) has properties of significant shrinkage deformation and early cracking, which limits its wide application in civil engineering applications. Waste fiber addition offers an effective solution to these challenges. This research focuses on waste glass fiber and explored the impact of various parameters on the performance of recycled glass fiber-reinforced self-compacting recycled aggregate concrete (RGF-SCRC). Incorporating waste glass fiber effectively inhibits the long-term shrinkage rate of RGF-SCRC and improves its axial compressive strength, with the improvement of 2.2∼15.3 % in axial compressive strength and a reduction of 17.9∼66.5 % in the long-term shrinkage rate. However, excessive fiber addition shows an negatively effect on the performance of RGF-SCRC. The optimum addition was concluded as 7.5 kg/m³. On the other hand, the waste alkali-resistant glass fiber showed a higher improvement than waste glass fiber. Moreover, microstructure analysis reveals that the waste fibers could be uniformly dispersed within the investigated specimen, effectively bridging gaps and significantly enhancing the concrete’s strength and toughness. Furthermore, the number of large pores and overall porosity were reduced, resulting in greater compactness, improved axial compressive strength, and reduced long-term shrinkage of RGF-SCRC. After 180 days of curing, the porosity of the specimens significantly decreased when compared to the 28 day curing specimens. Based on experimental results, the axial compression stress-strain relationship and long-term shrinkage curves of RGF-SCRC were fitted and modified, and proposed an axial compression constitutive relationship and a long-term shrinkage theoretical analysis model which are applicable to RGF-SCRC. The models' correctness was verified by comparing them with experimental results. These research outcomes offer valuable insights for the future practical implementation of RGF-SCRC.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139158"},"PeriodicalIF":7.4,"publicationDate":"2024-11-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664249","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}
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