Pub Date : 2024-11-15DOI: 10.1016/j.conbuildmat.2024.139182
Filip Broniewicz, Mirosław Broniewicz
Fibreglass lighting poles have gained a considerable amount of popularity in the market due to their advantages, and interest in them continues to grow. Consequently, the challenge of ensuring their safe design is becoming increasingly important. However, the current standard design procedure is not sufficient, because it does not consider one of the most common failure modes of composite poles, namely local buckling in the vicinity of the inspection opening. A verification of the standard’s calculated values has been done with the use of experimental testing. The calculated design bending strength was three times higher than the actual bending strength for 3.0 m high poles and twice higher for 9.0 m high poles. This paper proposes an improved method for estimating the bending resistance of composite poles with inspection openings. The method was developed using results from tests on full-scale poles, material sample tests, and experiments in a FEM environment. The proposed method provides more accurate results than the procedure for assessing the bending strength of these poles as presented in the EN 40–3–3 standard. The bending resistance value obtained using the modified calculation method is higher than the experimental value by an average of 6.6 %.
玻璃纤维照明灯杆因其优点而在市场上大受欢迎,人们对它们的兴趣也与日俱增。因此,如何确保其安全设计变得越来越重要。然而,目前的标准设计程序并不充分,因为它没有考虑到复合材料灯杆最常见的失效模式之一,即检查口附近的局部屈曲。通过实验测试对标准的计算值进行了验证。对于 3.0 米高的电杆,计算得出的设计抗弯强度是实际抗弯强度的三倍,而对于 9.0 米高的电杆,计算得出的设计抗弯强度是实际抗弯强度的两倍。本文提出了一种改进的方法,用于估算带有检查开口的复合材料电杆的抗弯强度。该方法是利用全尺寸电杆测试、材料样品测试和有限元环境实验的结果开发出来的。与 EN 40-3-3 标准中评估这些电杆抗弯强度的程序相比,所提出的方法能提供更精确的结果。使用修改后的计算方法得出的抗弯强度值比实验值平均高出 6.6%。
{"title":"Modified procedure for assessing the bending strength of composite GFRP poles","authors":"Filip Broniewicz, Mirosław Broniewicz","doi":"10.1016/j.conbuildmat.2024.139182","DOIUrl":"10.1016/j.conbuildmat.2024.139182","url":null,"abstract":"<div><div>Fibreglass lighting poles have gained a considerable amount of popularity in the market due to their advantages, and interest in them continues to grow. Consequently, the challenge of ensuring their safe design is becoming increasingly important. However, the current standard design procedure is not sufficient, because it does not consider one of the most common failure modes of composite poles, namely local buckling in the vicinity of the inspection opening. A verification of the standard’s calculated values has been done with the use of experimental testing. The calculated design bending strength was three times higher than the actual bending strength for 3.0 m high poles and twice higher for 9.0 m high poles. This paper proposes an improved method for estimating the bending resistance of composite poles with inspection openings. The method was developed using results from tests on full-scale poles, material sample tests, and experiments in a FEM environment. The proposed method provides more accurate results than the procedure for assessing the bending strength of these poles as presented in the EN 40–3–3 standard. The bending resistance value obtained using the modified calculation method is higher than the experimental value by an average of 6.6 %.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139182"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664189","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.2024.139157
Zhengyi Kong , Bo Yang , Xiaofei Wang , Cuiqiang Shi , Rui Li , Ningning Hu , Qinglin Tao , George Vasdravellis , Quang-Viet Vu
This study examines the stability behavior of corroded circular steel tubes (CST) under eccentric compression. Accelerated corrosion testing is utilized to obtain 12 CST with different corrosion degree, and 3D scanning technology is then applied to analyze the surface corrosion characteristics of the CST members. Eccentric compression tests are performed on the CST members to assess the impact of corrosion on the stability behavior. A finite element (FE) method with corrosion characteristics, based on the 3D reverse reconstructed method and surface corrosion characteristics, is developed for the prediction of buckling response of corroded CST. Corrosion weakens the mechanical properties of Q345B steel, progressively shortening or eliminating the yield plateau of stress-strain curves. When the corrosion rate reaches 21.47 %, the ultimate load and local buckling load of the CST members drop by 44.99 % and 43.44 %, respectively. Uniform corrosion primarily affects the bearing capacity (BCP) of CST members, while the failure mode of CST is significantly influenced by local corrosion. Current specifications are inaccuracy for the BCP of corroded CST under eccentric compression as they do not consider the impact of local corrosion. A new formula modified from current specification is developed to accurately predict the BCP of CST members after corrosion.
{"title":"Stability performance of corroded circular steel tube under eccentric compression","authors":"Zhengyi Kong , Bo Yang , Xiaofei Wang , Cuiqiang Shi , Rui Li , Ningning Hu , Qinglin Tao , George Vasdravellis , Quang-Viet Vu","doi":"10.1016/j.conbuildmat.2024.139157","DOIUrl":"10.1016/j.conbuildmat.2024.139157","url":null,"abstract":"<div><div>This study examines the stability behavior of corroded circular steel tubes (CST) under eccentric compression. Accelerated corrosion testing is utilized to obtain 12 CST with different corrosion degree, and 3D scanning technology is then applied to analyze the surface corrosion characteristics of the CST members. Eccentric compression tests are performed on the CST members to assess the impact of corrosion on the stability behavior. A finite element (FE) method with corrosion characteristics, based on the 3D reverse reconstructed method and surface corrosion characteristics, is developed for the prediction of buckling response of corroded CST. Corrosion weakens the mechanical properties of Q345B steel, progressively shortening or eliminating the yield plateau of stress-strain curves. When the corrosion rate reaches 21.47 %, the ultimate load and local buckling load of the CST members drop by 44.99 % and 43.44 %, respectively. Uniform corrosion primarily affects the bearing capacity (BCP) of CST members, while the failure mode of CST is significantly influenced by local corrosion. Current specifications are inaccuracy for the BCP of corroded CST under eccentric compression as they do not consider the impact of local corrosion. A new formula modified from current specification is developed to accurately predict the BCP of CST members after corrosion.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139157"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663829","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.2024.139046
Tenglong Rong , Jiawei Wang , Lujun Wang , Sheng Zhang , Xiaojian Ren , Yilu Yang , Yijia Zhou
In order to ensure the stability of rock-concrete composite (RCC) in coal mine underground reservoirs (CMURs), the theoretical damage model of the RCC was constructed in the present work. Considering the deformation compatibility between two different media of RCC on loading, the damage variable of RCC is deduced based upon the relationship between the damage variables of rock and concrete following the strain equivalence principle. Adjudging the failure of rock and concrete by different strength criteria, a damage model of RCC in coal mine underground reservoir (RCCD model) was developed. The experiments on the uniaxial and triaxial compressions of rock, concrete and RCC were used to validate the proposed damage model. The RCCD model curves exhibited four different periods in triaxial compression. The correlation coefficients between the values of RCCD model and the test values were determined to be 0.959, 0.981, 0.998 and 0.996. In addition, the correlation coefficients of rock and concrete were higher than 0.959. Moreover, the correlation of the parameters in the RCCD model was analyzed. The sensitivity of Weibull distribution parameters, height ratio coefficient, elastic modulus ratio and tension compression ratio of RCC were discussed. The study illustrates that the proposed RCCD model can satisfactorily characterize the mechanical characteristics of RCC under various loadings.
{"title":"A damage model of rock-concrete composite in coal mine underground reservoirs","authors":"Tenglong Rong , Jiawei Wang , Lujun Wang , Sheng Zhang , Xiaojian Ren , Yilu Yang , Yijia Zhou","doi":"10.1016/j.conbuildmat.2024.139046","DOIUrl":"10.1016/j.conbuildmat.2024.139046","url":null,"abstract":"<div><div>In order to ensure the stability of rock-concrete composite (RCC) in coal mine underground reservoirs (CMURs), the theoretical damage model of the RCC was constructed in the present work. Considering the deformation compatibility between two different media of RCC on loading, the damage variable of RCC is deduced based upon the relationship between the damage variables of rock and concrete following the strain equivalence principle. Adjudging the failure of rock and concrete by different strength criteria, a damage model of RCC in coal mine underground reservoir (RCCD model) was developed. The experiments on the uniaxial and triaxial compressions of rock, concrete and RCC were used to validate the proposed damage model. The RCCD model curves exhibited four different periods in triaxial compression. The correlation coefficients between the values of RCCD model and the test values were determined to be 0.959, 0.981, 0.998 and 0.996. In addition, the correlation coefficients of rock and concrete were higher than 0.959. Moreover, the correlation of the parameters in the RCCD model was analyzed. The sensitivity of Weibull distribution parameters, height ratio coefficient, elastic modulus ratio and tension compression ratio of RCC were discussed. The study illustrates that the proposed RCCD model can satisfactorily characterize the mechanical characteristics of RCC under various loadings.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139046"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664247","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.2024.138940
Rong Xi , Jian Xie , Tao Wang , Jia-Bao Yan
This study experimentally investigated the quasi-static and dynamic compressive stress-strain behaviours of wet-sieved mortar (WSM) at 20 °C–−165 °C. Quasi-static and dynamic compression tests were carried out on 129 WSM cylinders using a 2000-kN universal test machine and a Ø75-mm split Hopkinson pressure bar device combined with a high-speed camera. Strain rates and low temperatures greatly influenced the failure processes and modes of WSM materials subjected to dynamic compression loadings. Test results showed that the decreasing temperature enhanced the strain rate effects on compressive strength and strain, modulus of elasticity, and specific energy absorption. Specifically, compared with the static compressive strength at ambient temperatures, the compressive strength at a strain rate of 200 s-1 was increased by 106.7 % and 251.2 % as the temperature equalled to 20 °C and −165 °C, respectively. Furthermore, empirical equations of low-temperature dynamic increasing factors were established through regression analyses. Finally, a modified low-temperature dynamic stress-strain model was proposed for WSM materials. Validations confirmed that the developed model reasonably described the stress-strain behaviours of WSM materials at 20 °C–−165 °C. The study results can be utilized to optimize the design of concrete at low temperatures, and the proposed stress-strain relationships can be employed to conduct more precise dynamic mesoscopic numerical simulations.
{"title":"Quasi-static and dynamic compressive behaviours of wet-sieved mortar at low temperatures","authors":"Rong Xi , Jian Xie , Tao Wang , Jia-Bao Yan","doi":"10.1016/j.conbuildmat.2024.138940","DOIUrl":"10.1016/j.conbuildmat.2024.138940","url":null,"abstract":"<div><div>This study experimentally investigated the quasi-static and dynamic compressive stress-strain behaviours of wet-sieved mortar (WSM) at 20 °C–−165 °C. Quasi-static and dynamic compression tests were carried out on 129 WSM cylinders using a 2000-kN universal test machine and a Ø75-mm split Hopkinson pressure bar device combined with a high-speed camera. Strain rates and low temperatures greatly influenced the failure processes and modes of WSM materials subjected to dynamic compression loadings. Test results showed that the decreasing temperature enhanced the strain rate effects on compressive strength and strain, modulus of elasticity, and specific energy absorption. Specifically, compared with the static compressive strength at ambient temperatures, the compressive strength at a strain rate of 200 s-1 was increased by 106.7 % and 251.2 % as the temperature equalled to 20 °C and −165 °C, respectively. Furthermore, empirical equations of low-temperature dynamic increasing factors were established through regression analyses. Finally, a modified low-temperature dynamic stress-strain model was proposed for WSM materials. Validations confirmed that the developed model reasonably described the stress-strain behaviours of WSM materials at 20 °C–−165 °C. The study results can be utilized to optimize the design of concrete at low temperatures, and the proposed stress-strain relationships can be employed to conduct more precise dynamic mesoscopic numerical simulations.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 138940"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664193","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.2024.139087
Muhammad Riaz Ahmad , Ana Fernàndez-Jimenez , Bing Chen , Zhen Leng , Jian-Guo Dai
The construction industry's heavy reliance on ordinary Portland cement (OPC) significantly contributes to global carbon emissions, accounting for 7–9 % of CO2 emissions. This paper reviews low-carbon cementitious materials (LCCMs) as sustainable alternatives to OPC. Key LCCMs examined include supplementary cementitious materials (SCMs), limestone calcined clay cements (LC3), alkali-activated materials (AAMs), belite-rich Portland cements (BRPCs), ye’elimite-rich cements (YRCs), and non-hydraulic carbonatable binders (CBs). The paper examines the reaction mechanisms, hydration products, and properties of these materials, whereas scalability potential, cost, environmental impact, barriers, and research gaps are also highlighted. LC3 demonstrates high scalability potential due to its similarities with OPC, cost-effectiveness, and the abundant availability of raw materials. Environmentally, AAMs offer the most significant impact reduction, achieving a 40–75 % decrease compared to OPC, followed by LC3 (∼40 %), CBs (∼37 %), YRC (∼20–25 %), and BRPC (∼10 %). However, the costs of AAMs, YRC, and CBs may be higher than OPC and other LCCMs. Technical challenges and research gaps for LCCMs include low reactivity of SCMs, low early-age strength, prolonged setting times, availability of suitable activators, finding compatible superplasticizers, and a lack of long-term performance studies, which shall be further explored in the future. Existing infrastructure may not be adaptable for the new LCCMs, which may require a significant initial investment. Policy barriers are also significant, as updating standards is linked with the satisfactory long-term performance of LCCMs and is hindered by the dominance of OPC market. There is a need of enhanced collaboration efforts among researchers, industry, and policymakers to overcome these technical, economic, and policy barriers, paving the way for sustainable construction practices.
{"title":"Low-carbon cementitious materials: Scale-up potential, environmental impact and barriers","authors":"Muhammad Riaz Ahmad , Ana Fernàndez-Jimenez , Bing Chen , Zhen Leng , Jian-Guo Dai","doi":"10.1016/j.conbuildmat.2024.139087","DOIUrl":"10.1016/j.conbuildmat.2024.139087","url":null,"abstract":"<div><div>The construction industry's heavy reliance on ordinary Portland cement (OPC) significantly contributes to global carbon emissions, accounting for 7–9 % of CO<sub>2</sub> emissions. This paper reviews low-carbon cementitious materials (LCCMs) as sustainable alternatives to OPC. Key LCCMs examined include supplementary cementitious materials (SCMs), limestone calcined clay cements (LC3), alkali-activated materials (AAMs), belite-rich Portland cements (BRPCs), ye’elimite-rich cements (YRCs), and non-hydraulic carbonatable binders (CBs). The paper examines the reaction mechanisms, hydration products, and properties of these materials, whereas scalability potential, cost, environmental impact, barriers, and research gaps are also highlighted. LC3 demonstrates high scalability potential due to its similarities with OPC, cost-effectiveness, and the abundant availability of raw materials. Environmentally, AAMs offer the most significant impact reduction, achieving a 40–75 % decrease compared to OPC, followed by LC3 (∼40 %), CBs (∼37 %), YRC (∼20–25 %), and BRPC (∼10 %). However, the costs of AAMs, YRC, and CBs may be higher than OPC and other LCCMs. Technical challenges and research gaps for LCCMs include low reactivity of SCMs, low early-age strength, prolonged setting times, availability of suitable activators, finding compatible superplasticizers, and a lack of long-term performance studies, which shall be further explored in the future. Existing infrastructure may not be adaptable for the new LCCMs, which may require a significant initial investment. Policy barriers are also significant, as updating standards is linked with the satisfactory long-term performance of LCCMs and is hindered by the dominance of OPC market. There is a need of enhanced collaboration efforts among researchers, industry, and policymakers to overcome these technical, economic, and policy barriers, paving the way for sustainable construction practices.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139087"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664026","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}
The research evaluates the performance of Stone Mastic Asphalt (SMA) mixtures using residual cotton fibres from the Peruvian textile industry to address the environmental pollution caused by this sector. A reference SMA20 mixture was established with 0.30 % commercial fibre and 6 % asphalt. Subsequently, this fibre was replaced by textile fibre in the same proportions. It was found that 0.20 % textile fibre optimally met the volumetric requirements and binder drainage tests. Performance tests showed that the textile fibre achieved a TSR of 95 %, compared to 82 % for the commercial fibre, and a rutting resistance of 2.82 mm compared to 2.46 mm for the commercial fibre. Additionally, the textile fibre demonstrated a better dynamic modulus at high temperatures. In conclusion, residual Peruvian cotton fibres can efficiently replace commercial fibres in SMA20 mixtures, with 0.20 % being the optimal amount, thus promoting sustainable material reuse.
{"title":"Performance evaluation of Stone Mastic Asphalt (SMA) mixtures with textile waste fibres","authors":"Wilder Rodríguez , Julián Rivera , Miguel Sevillano , Tania Torres","doi":"10.1016/j.conbuildmat.2024.139125","DOIUrl":"10.1016/j.conbuildmat.2024.139125","url":null,"abstract":"<div><div>The research evaluates the performance of Stone Mastic Asphalt (SMA) mixtures using residual cotton fibres from the Peruvian textile industry to address the environmental pollution caused by this sector. A reference SMA20 mixture was established with 0.30 % commercial fibre and 6 % asphalt. Subsequently, this fibre was replaced by textile fibre in the same proportions. It was found that 0.20 % textile fibre optimally met the volumetric requirements and binder drainage tests. Performance tests showed that the textile fibre achieved a TSR of 95 %, compared to 82 % for the commercial fibre, and a rutting resistance of 2.82 mm compared to 2.46 mm for the commercial fibre. Additionally, the textile fibre demonstrated a better dynamic modulus at high temperatures. In conclusion, residual Peruvian cotton fibres can efficiently replace commercial fibres in SMA20 mixtures, with 0.20 % being the optimal amount, thus promoting sustainable material reuse.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139125"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663739","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}
Efflorescence of geopolymers is a common phenomenon, which is caused by overuse of activators and dissolution-crystallization of carbonate. It has been widely focused on, but its behavior and mechanism remain highly disputed. In the study, the behavior and mechanism of four alkali-activated burnt coal cinder-based geopolymers under two curing conditions of intensifying and inhibiting efflorescence was discussed. The study results show that the deterioration of geopolymer properties caused by efflorescence has a strong timeliness and is closely related to the progress of geopolymerization. Furthermore, through comparative verification of performance testing and phases analysis, the direct factor of the degradation of geopolymer properties is not the carbonate produced by excessive alkaline activators. The direct factor of it is that soluble active components (Si, Al or P) are carried to the surface of the geopolymer by the efflorescence substances, resulting in the permanent loss of gel products. Moreover, the efflorescence also shows a complex and close relationship with the types of activator combination, pore structure and curing system. The perception of the association between efflorescence formation and affecting factors provides important insights into the manufacturing and application of geopolymer related materials.
{"title":"Efflorescence behavior and mechanism of burnt coal cinder-based geopolymers under different alkali activators","authors":"Muyang Huang , Shenxu Bao , Yimin Zhang , Zichen Zhou , Xiangke Jiao","doi":"10.1016/j.conbuildmat.2024.139057","DOIUrl":"10.1016/j.conbuildmat.2024.139057","url":null,"abstract":"<div><div>Efflorescence of geopolymers is a common phenomenon, which is caused by overuse of activators and dissolution-crystallization of carbonate. It has been widely focused on, but its behavior and mechanism remain highly disputed. In the study, the behavior and mechanism of four alkali-activated burnt coal cinder-based geopolymers under two curing conditions of intensifying and inhibiting efflorescence was discussed. The study results show that the deterioration of geopolymer properties caused by efflorescence has a strong timeliness and is closely related to the progress of geopolymerization. Furthermore, through comparative verification of performance testing and phases analysis, the direct factor of the degradation of geopolymer properties is not the carbonate produced by excessive alkaline activators. The direct factor of it is that soluble active components (Si, Al or P) are carried to the surface of the geopolymer by the efflorescence substances, resulting in the permanent loss of gel products. Moreover, the efflorescence also shows a complex and close relationship with the types of activator combination, pore structure and curing system. The perception of the association between efflorescence formation and affecting factors provides important insights into the manufacturing and application of geopolymer related materials.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139057"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664158","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.2024.139206
Jiahao Liu , Cong Qi , Quantao Liu , Huan Wang , Chong Wang , Yonghan Zhang , Shaopeng Wu , Na Li
During the construction process, the rubber asphalt (RA) results in the generation of considerable quantities of noxious fumes, endangering the safety of those employed in the field and causing unavoidable environmental damage. The traditional inorganic fume suppressants can reduce fume emissions, but compromise the low-temperature performance of asphalt. This paper addresses this issue by employing a combination of organic inhibitor and inorganic fume suppressant. Mechanical and rheological experiments reveal that the organic-inorganic composite inhibitor simultaneously enhance the rutting resistance of RA at high temperatures and the cracking resistance at low temperatures. The results of gas chromatography-mass spectrometry (GC-MS) show that the types of hydrocarbon derivatives (HYDs) and sulfides substances (SCs) in the volatile organic compounds (VOCs) of inorganic- organic composite inhibitor modified asphalt (INOORA) are reduced by 71.4 % and 76.9 % compared to RA, respectively. Brunauer-Emmett-Teller (BET), Fourier Transform Infrared Test (FT-IR), and Thermogravimetric analysis (TG-DTG) results suggest that the organic inhibitor reacts chemically with rubber asphalt components, increasing the size of certain small molecular VOCs in rubber asphalt, which is more readily adsorbed by the pores of diatomaceous earth, thereby synergistically reducing the VOCs concentration in rubber asphalt. The results provided a new method for preventing the volatilization of noxious substances from rubber asphalt, without compromising its road performance.
在施工过程中,橡胶沥青(RA)会产生大量有毒烟雾,危及现场工作人员的安全,并对环境造成不可避免的破坏。传统的无机烟雾抑制剂可以减少烟雾排放,但会影响沥青的低温性能。本文采用有机抑制剂和无机烟尘抑制剂的组合来解决这一问题。机械和流变实验表明,有机-无机复合抑制剂可同时增强 RA 在高温下的抗车辙能力和低温下的抗开裂能力。气相色谱-质谱(GC-MS)分析结果表明,无机-有机复合抑制剂改性沥青(INOORA)的挥发性有机化合物(VOCs)中碳氢化合物衍生物(HYDs)和硫化物(SCs)的种类与 RA 相比分别减少了 71.4% 和 76.9%。布鲁瑙尔-艾美特-泰勒(BET)、傅立叶变换红外测试(FT-IR)和热重分析(TG-DTG)结果表明,有机抑制剂与橡胶沥青成分发生化学反应,增大了橡胶沥青中某些小分子 VOC 的尺寸,而硅藻土的孔隙更容易吸附这些小分子 VOC,从而协同降低了橡胶沥青中的 VOC 浓度。研究结果为防止橡胶沥青中有害物质的挥发提供了一种新方法,同时又不影响其路面性能。
{"title":"Study on the effects of organic-inorganic composite inhibitor on fume emissions of rubber modified asphalt","authors":"Jiahao Liu , Cong Qi , Quantao Liu , Huan Wang , Chong Wang , Yonghan Zhang , Shaopeng Wu , Na Li","doi":"10.1016/j.conbuildmat.2024.139206","DOIUrl":"10.1016/j.conbuildmat.2024.139206","url":null,"abstract":"<div><div>During the construction process, the rubber asphalt (RA) results in the generation of considerable quantities of noxious fumes, endangering the safety of those employed in the field and causing unavoidable environmental damage. The traditional inorganic fume suppressants can reduce fume emissions, but compromise the low-temperature performance of asphalt. This paper addresses this issue by employing a combination of organic inhibitor and inorganic fume suppressant. Mechanical and rheological experiments reveal that the organic-inorganic composite inhibitor simultaneously enhance the rutting resistance of RA at high temperatures and the cracking resistance at low temperatures. The results of gas chromatography-mass spectrometry (GC-MS) show that the types of hydrocarbon derivatives (HYDs) and sulfides substances (SCs) in the volatile organic compounds (VOCs) of inorganic- organic composite inhibitor modified asphalt (INOORA) are reduced by 71.4 % and 76.9 % compared to RA, respectively. Brunauer-Emmett-Teller (BET), Fourier Transform Infrared Test (FT-IR), and Thermogravimetric analysis (TG-DTG) results suggest that the organic inhibitor reacts chemically with rubber asphalt components, increasing the size of certain small molecular VOCs in rubber asphalt, which is more readily adsorbed by the pores of diatomaceous earth, thereby synergistically reducing the VOCs concentration in rubber asphalt. The results provided a new method for preventing the volatilization of noxious substances from rubber asphalt, without compromising its road performance.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139206"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664025","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.2024.139184
Wei Dong , Junfeng Wang
Northwest China, represented by Inner Mongolia, is rich in desert resources, and the reasonable use of aeolian sand (AS) as fine aggregate for the preparation of aeolian sand concrete (ASC) can not only reduce land desertification but also alleviate the shortage of river sand (RS) resources. At the same time, more salt lakes in Inner Mongolia lead to concrete structures often accompanied by salt corrosion and freeze-thaw cycle (FTC) and other erosion effects. Therefore, this paper carries out the capillary water absorption (CWA) test on ASC under the coupling of sulphate FTC, and analyses the effects of different erosive environments (5 %Na2SO4, 10 %Na2SO4, 5 %Na2SO4+3.5 %NaCl) and the amount of AS dosage (0 %, 20 %, 100 %) on the CWA performance of ASC. The results show that, under the coupling effect of sulphate FTC, the expansion stress produced by moisture phase change and erosion products increases continuously, the initial defects inside the concrete develop continuously, the percentage of gel pores and less harmful pores decreases gradually, the compressive strength, relative dynamic elastic modulus (RDEM) and mass decrease gradually, and the concrete is damaged most seriously in the composite salt environment. The CWA of ASC mainly occurs before 2 h1/2, and there is a good correlation between the initial water absorption rate (IWAR) and the depth of CWA and the degree of freeze-thaw damage. The cumulative water absorption and the IWAR of ASC became smaller with the increase of AS dosage. By applying the fractal theory to the pore structure, it was found that the relationship between the fractal dimension and the IWAR and damage degree was good, and that a reasonable increase in the proportion of small pores below 50 nm was more favourable to the frost durability of ASC.
{"title":"Research on capillary water absorption characteristics of aeolian sand concrete under sulfate freeze-thaw coupling based on fractal theory","authors":"Wei Dong , Junfeng Wang","doi":"10.1016/j.conbuildmat.2024.139184","DOIUrl":"10.1016/j.conbuildmat.2024.139184","url":null,"abstract":"<div><div>Northwest China, represented by Inner Mongolia, is rich in desert resources, and the reasonable use of aeolian sand (AS) as fine aggregate for the preparation of aeolian sand concrete (ASC) can not only reduce land desertification but also alleviate the shortage of river sand (RS) resources. At the same time, more salt lakes in Inner Mongolia lead to concrete structures often accompanied by salt corrosion and freeze-thaw cycle (FTC) and other erosion effects. Therefore, this paper carries out the capillary water absorption (CWA) test on ASC under the coupling of sulphate FTC, and analyses the effects of different erosive environments (5 %Na<sub>2</sub>SO<sub>4</sub>, 10 %Na<sub>2</sub>SO<sub>4</sub>, 5 %Na<sub>2</sub>SO<sub>4</sub>+3.5 %NaCl) and the amount of AS dosage (0 %, 20 %, 100 %) on the CWA performance of ASC. The results show that, under the coupling effect of sulphate FTC, the expansion stress produced by moisture phase change and erosion products increases continuously, the initial defects inside the concrete develop continuously, the percentage of gel pores and less harmful pores decreases gradually, the compressive strength, relative dynamic elastic modulus (RDEM) and mass decrease gradually, and the concrete is damaged most seriously in the composite salt environment. The CWA of ASC mainly occurs before 2 h<sup>1/2</sup>, and there is a good correlation between the initial water absorption rate (IWAR) and the depth of CWA and the degree of freeze-thaw damage. The cumulative water absorption and the IWAR of ASC became smaller with the increase of AS dosage. By applying the fractal theory to the pore structure, it was found that the relationship between the fractal dimension and the IWAR and damage degree was good, and that a reasonable increase in the proportion of small pores below 50 nm was more favourable to the frost durability of ASC.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139184"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142663768","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.2024.139166
Yafei Ma , Jie Yang , Xiaochao Su , Anyin Peng , Lei Wang , Ke Huang
The steel strands in pretensioned prestressed concrete are susceptible to corrosion and expansion due to threatening environmental conditions, leading to concrete cracking, reduction in the bearing capacity and durability of structures. This paper presents an electrochemical accelerated corrosion test on steel strands. The internal strain, surface strain, and crack propagation in concrete specimens during the entire corrosion process of steel strands are continuously monitored using the digital image correlation (DIC) method and strain detection methods. The study investigates the effects of concrete cover thickness and stirrup arrangement on the surface strain field and crack propagation in concrete. A mesoscopic numerical model of concrete cracking under non-uniform corrosion of steel strands is established. The reliability of the constructed model is verified using experimental data. The results show that compared with traditional strain detection methods, the DIC method can detect initial cracks on the concrete surface 20 hours in advance. The proposed non-uniform mesoscopic simulation model can accurately simulate the entire process of concrete cracking induced by non-uniform corrosion of steel strands. The finite element (FE) model is consistent with the results obtained from DIC monitoring.
{"title":"Crack propagation characterization of concrete under non-uniform corrosion of steel strand using digital image correlation","authors":"Yafei Ma , Jie Yang , Xiaochao Su , Anyin Peng , Lei Wang , Ke Huang","doi":"10.1016/j.conbuildmat.2024.139166","DOIUrl":"10.1016/j.conbuildmat.2024.139166","url":null,"abstract":"<div><div>The steel strands in pretensioned prestressed concrete are susceptible to corrosion and expansion due to threatening environmental conditions, leading to concrete cracking, reduction in the bearing capacity and durability of structures. This paper presents an electrochemical accelerated corrosion test on steel strands. The internal strain, surface strain, and crack propagation in concrete specimens during the entire corrosion process of steel strands are continuously monitored using the digital image correlation (DIC) method and strain detection methods. The study investigates the effects of concrete cover thickness and stirrup arrangement on the surface strain field and crack propagation in concrete. A mesoscopic numerical model of concrete cracking under non-uniform corrosion of steel strands is established. The reliability of the constructed model is verified using experimental data. The results show that compared with traditional strain detection methods, the DIC method can detect initial cracks on the concrete surface 20 hours in advance. The proposed non-uniform mesoscopic simulation model can accurately simulate the entire process of concrete cracking induced by non-uniform corrosion of steel strands. The finite element (FE) model is consistent with the results obtained from DIC monitoring.</div></div>","PeriodicalId":288,"journal":{"name":"Construction and Building Materials","volume":"455 ","pages":"Article 139166"},"PeriodicalIF":7.4,"publicationDate":"2024-11-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142664160","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}