Materials and Structures最新文献

{"title":"Experimental investigation on bond performance of UHPFRC wet joint by direct tension test","authors":"Haichun Li,&nbsp;Chuanxi Li,&nbsp;Yumei Wen,&nbsp;Zijian Zhu,&nbsp;Jiahao Peng,&nbsp;Siyang Li,&nbsp;Zheng Feng","doi":"10.1617/s11527-024-02421-y","DOIUrl":"10.1617/s11527-024-02421-y","url":null,"abstract":"<div><p>Ultra-high-performance fiber-reinforced concrete (UHPFRC) is applied to joint nodes with its excellent mechanical properties, which helps to improve the force transfer performance of UHPFRC structures. The strength of the connections is dependent on the adhesion and friction between the connected materials in the bridge design procedure. This research aims to identify the adhesion performance between UHPFRC and UHPFRC under different interfacial roughening methods. To this end, the maximum tensile stress and the load–displacement curves of UHPFRC wet joints treated by high-pressure water jet roughening, uniform plastic formwork roughening, embedded wire mesh roughening, manual mechanical roughening, and epoxy resin were obtained via direct tension tests. The test results indicate that the bond strength of UHPFRC wet joints can reach 22.36%-68.06% of the tensile strength after different interfacial treatments, among which the roughening methods using high-pressure water jet significantly improve the bond performance of UHPFRC wet joints, followed by the roughing method of uniform plastic formwork and embedded steel wire mesh. Physical roughening treatment has less effect on the stiffness of UHPFRC wet joints and exhibits a typical brittle failure mode. A tensile constitutive model in the elastic phase of the UHPFRC wet joint interface and the simplified interfacial tensile stress-relative displacement model were proposed. Finally, the performance of the interfacial adhesion parameters was appraised by finite element modeling. The finite element analysis showed a good agreement with the experimental results.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141609752","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Assessing the setting behavior of ultra-high performance concrete","authors":"Naveen Saladi,&nbsp;Luca Montanari,&nbsp;Alireza Mohebbi,&nbsp;Michelle A. Cooper,&nbsp;Benjamin Graybeal","doi":"10.1617/s11527-024-02408-9","DOIUrl":"10.1617/s11527-024-02408-9","url":null,"abstract":"<div><p>The setting behavior of ultra-high performance concrete (UHPC) is demonstrably different from that of conventional concrete; thus, tools and guidance extending beyond common test methods such as Vicat and penetration are needed. While UHPC is known for its enhanced mechanical and durability properties, due to the low water and high cementitious contents, UHPC-class materials are prone to early-age autogenous shrinkage. Recognizing that UHPCs are commonly supplied to construction sites as prebagged, proprietary mixes with unknown constituents, and that accurate determination of setting time is crucial in determining the early-age autogenous shrinkage of UHPC-class materials as well as for scheduling construction operations and quality control actions, this study explores alternate test methods such as isothermal calorimetry (ASTM C1679), semi-adiabatic calorimetry (ASTM C1753), autogenous shrinkage (ASTM C1698), chemical shrinkage (ASTM C1608), and dual ring test (American Association of State Highway and Transportation Officials (AASHTO T 363) to evaluate the setting behavior of UHPCs. Setting times obtained using the alternate test methods aligned well with each other and were found to be different than the setting times indicated through standard test methods. Discussion and guidance on the applicability and the use of alternate test methods to determine the setting time of UHPCs for various laboratory and field applications are provided.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-024-02408-9.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141577744","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Effect of different carbonate fillers on the durability of mortars","authors":"Antonela Di Salvo Barsi,&nbsp;Gisela Cordoba,&nbsp;Mónica A. Trezza,&nbsp;Edgardo F. Irassar","doi":"10.1617/s11527-024-02414-x","DOIUrl":"10.1617/s11527-024-02414-x","url":null,"abstract":"<div><p>This paper investigates the durability performance of mortars with varying replacement levels of dolostone or limestone filler (0–30% by mass) and the stability of mortars with dolostone filler for 2 years. Compressive strength, total porosity, capillary water absorption, and chloride migration coefficients were determined. Results show that compressive strength decreases and the total porosity increases with increasing filler content due to a dilution effect, regardless of the filler composition. The capillary water absorption and the chloride migration coefficients rise significantly for mortars with 20–30% filler. However, the dolostone filler cements have lower chloride coefficients than those with limestone blended cement. Volumetric stability assessments reveal no significant expansion, and XRD and FT-IR analyses suggest the formation of hydrotalcite-like phases.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141572278","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Experiments and modeling of structural behavior of different BFRP reinforcements in concrete compressive members","authors":"Zeeshan Ahmad,&nbsp;Abdelatif Salmi,&nbsp;Mohamed Hechmi El Ouni,&nbsp;Mohd Ahmed,&nbsp;Bilal Ahmed,&nbsp;Nejib Ghazouani","doi":"10.1617/s11527-024-02416-9","DOIUrl":"10.1617/s11527-024-02416-9","url":null,"abstract":"<div><p>Previous investigations have primarily focused on the use of circular basalt fiber reinforced polymer (BFRP) bars in concrete compression members, neglecting the application of these lightweight composites in different structural sections. This study aims to address this research gap by examining the structural efficiency of square concrete compressive members reinforced with various BFRP sections. A total of eight samples were cast, including seven with BFRP angle sections, BFRP plate sections, BFRP tubes, and BFRP circular rebars, and one control sample with conventional steel rebars as the main reinforcement and stainless steel rebars as lateral reinforcement. All samples had a square cross-section of 200 mm width and 1200 mm height, except for the BFRP tube compressive member, which had a cross-section of 180 mm × 180 mm and the same height. The experimental results demonstrated that failure patterns were influenced by the reinforcement material, reinforcement section, and vertical spacing of stainless-steel stirrups. The sample with steel reinforcement exhibited the highest strength of 1451 kN. The ultimate strength reductions for samples with BFRP angle sections, BFRP plate sections, BFRP tubes, and BFRP circular rebars were 22%, 10.3%, 49.6%, and 10%, respectively. The study found that the vertical spacing of ties significantly impacted the load–deflection behavior. For angle section BFRP rebars, increasing the tie spacing from 50 to 100 mm resulted in a 9.50% increase in strength and a 22.20% increase in axial deflection. In contrast, for plate section BFRP rebars, increasing the tie spacing led to a 14.2% decrease in load and a 5.7% decrease in deflection. Members reinforced with BFRP circular rebars showed a 4% decrease in strength and a 13.4% increase in deflection. A finite element analysis (FEA) model was developed to evaluate the structural efficiency of members reinforced with BFRP sections and to conduct a parametric investigation. The concrete damaged plasticity (CDP) model was employed in the FEA to simulate concrete behavior. The proposed FEA model showed discrepancies of 7.2% for the ultimate load and 5.5% for the equivalent deflection and accurately captured crack patterns. Additionally, to compare with theoretical computations, predictions from three international codes were calculated to highlight differences between experimental measurements, FEA results, and theoretical predictions.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-07-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141550879","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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 the end conditions on the response of glass textile reinforced cementitious composites under uniaxial tension","authors":"Ramakrishna Samanthula,&nbsp;Ravindra Gettu,&nbsp;Sachin Paul,&nbsp;Raul Luis Zerbino","doi":"10.1617/s11527-024-02413-y","DOIUrl":"10.1617/s11527-024-02413-y","url":null,"abstract":"<div><p>Textile Reinforced Concrete is a cementitious composite with non-metallic distributed reinforcement, which could exhibit strain-hardening response under uniaxial tensile loading. The tensile behaviour must be characterized properly in order to obtain reliable and appropriate input for structural design. However, it is seen that the end conditions of the test specimen could affect the response, which is discussed in this paper by considering two extreme types of boundary conditions, with the end rotation during testing either being negated or permitted. The strains and displacements were monitored using Digital Image Correlation, along with axial extensometers. The data indicate that fixed ends result in unsymmetric cracking and non-uniform strain distribution across the lateral section of the test specimen whereas rotating ends lead to more uniform cracking and strain distributions. It was further found that the mean width of the strain localization zone is larger for rotating ends. On the other hand, ultimate stress and strain, as well as the average crack opening are comparable for both the end conditions, The maximum crack widths were in the order of 0.2 mm for about 0.8% nominal strain (i.e., close to failure), for the specimens considered. The analysis suggests that rotating end conditions be used to obtain more unambiguous response.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-07-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-024-02413-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141550880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Enhancing bio-based concrete mechanical properties: a novel approach with composite sandwiches and confined cylinders","authors":"Rafik Bardouh,&nbsp;Omayma Homoro,&nbsp;Nadège Reboul,&nbsp;Mohamed Saidi,&nbsp;Sofiane Amziane","doi":"10.1617/s11527-024-02400-3","DOIUrl":"10.1617/s11527-024-02400-3","url":null,"abstract":"<div><p>This paper addresses the growing use of bio-based materials in Europe, thanks to their low embodied energy and carbon sequestration. Despite favorable hygrothermal and acoustic properties, the inherent challenge lies in the low mechanical properties of biobased concrete. This study presents an innovative approach to strengthen hemp concrete through natural FRCM (Fabric Reinforced Cementitious Matrix), using two distinct reinforcement techniques. Firstly, a bending reinforcement consists of applying natural FRCM as the outer skins of a composite sandwich, with hemp concrete as the core. The effect of textile layers and pre-impregnation on the FRCM mechanical properties within the composite sandwich is evaluated. Secondly, compressive reinforcement entails confining hemp concrete specimens with FRCM. The results show a significant improvement in the mechanical properties of hemp concrete, with bending and compressive reinforcement leading to increases in the mechanical strength up to 17,530% and 258%, respectively. Configurations involving mineral-impregnated fabric (PM FRCM) demonstrate superior mechanical reinforcement since it allows a better interphase bond between fabric and cementitious matrix. Different failure modes are observed between reference (non-reinforced) specimens and reinforced specimens, with bending reinforced specimens exhibiting shear failure and debonding at the interface of the composite sandwich, while reference specimens fail in bending. Moreover, compressive reinforced specimens undergo crushing of hemp concrete after tensioning rupture of the fabric, while reference specimens present angular shear path in the middle of the specimens. The results underscore the promise of FRCM in mechanically reinforcing bio-based concrete, opening new opportunities for their expanded use in the construction industry.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-024-02400-3.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141512934","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Experimental research on seismic performance of hybrid connected prefabricated composite columns","authors":"Zhangfeng Zhu,&nbsp;Pengcheng Jin,&nbsp;Yongfeng Zheng,&nbsp;Baoqian Zhang","doi":"10.1617/s11527-024-02415-w","DOIUrl":"10.1617/s11527-024-02415-w","url":null,"abstract":"<div><p>Ensuring the reliability of the joint of prefabricated composite columns is crucial for the overall performance of assembled steel–concrete composite structures. Hybrid connected prefabricated composite columns, utilizing the steel pipe connection with post-tensioning connection, was proposed to enhance the joint integrity. Horizontal low-cyclic repeated loading test was performed on one cast-in-place specimen and three precast specimens with varying steel pipes. The precast specimens exhibited higher load carrying capacity, stiffness and ductility properties along with comparable energy consumption capacity, compared to the cast-in-place specimen. The impact of parameters such as sectional dimension and anchorage length of the steel pipe, thickness of cover plates, and post-tensioning stress, was also examined based on the experimental results and corresponding finite element analysis.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-024-02415-w.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141508271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Coupling effect of freezing-thawing cycles and dynamic loading on the accumulative deformation and microstructure of foam concrete","authors":"Zhen-Dong Cui,&nbsp;Long-Ji Zhang,&nbsp;Kun-Kun Fan,&nbsp;Li Yuan","doi":"10.1617/s11527-024-02409-8","DOIUrl":"10.1617/s11527-024-02409-8","url":null,"abstract":"<div><p>Foam concrete is characterized by lightweight, self-compacting and high flowability, thereby widely used as a subgrade bed filler. High-speed railway subgrades usually experience inhomogeneous deformation due to the occurrence of freezing-thawing cycles in seasonally frozen soil areas. It is essential to study the deformation behavior of foam concrete under the coupling effect of freezing-thawing cycles and dynamic loading. In this paper, dynamic triaxial tests were performed to study the accumulative deformation of the foam concrete under different numbers of freezing-thawing cycles, freezing temperatures, amplitudes and frequencies of dynamic loading. Based on the scanning electron microscopy (SEM) tests, the characteristics of the pore structure were analyzed quantitatively by introducing the directional distribution frequency and fractal dimension. The research results illustrate that the damage caused by freezing-thawing progress to the pore structure results in more significant deformation of the foam concrete subjected to dynamic loading. There exists an accumulative damage effect induced by the coupling action of long-term dynamic loading and freezing-thawing progress on the microstructure and mechanical properties of foam concrete. The development of the fractal dimension agrees with that of the accumulative strain, indicating a close connection between the microstructure and the dynamic behavior of foam concrete. The findings concluded in this study contribute to a sufficient understanding of the performance of foam concrete used as high-speed railway subgrade fillers subjected to seasonal freezing.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-024-02409-8.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141508272","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Strengthening cement paste via organic-inorganic network formation","authors":"Qing Liu,&nbsp;Yunjian Li,&nbsp;Qiao Wang,&nbsp;Miaomiao Wang,&nbsp;Zongjin Li,&nbsp;Guoqing Geng","doi":"10.1617/s11527-024-02405-y","DOIUrl":"10.1617/s11527-024-02405-y","url":null,"abstract":"<div><p>The inherent brittleness of cement hydrates poses a major issue to the mechanical and durable performances of concrete. To conquer this issue, we constructed an organic–inorganic network within the cement matrix by utilizing the synergy of in situ polymerization of monomers and cement hydration, which significantly enhances its flexural strength and toughness while maintaining a comparable compressive strength with ordinary Portland cement (OPC). By tuning the proportions of acrylic acid (AA), methacrylic acid (MAA), and acrylamide (AM), the cement paste experienced an 86% increase in flexural strength with a similar compressive strength to OPC. The in situ formed organic–inorganic (polymer-cement) network provided both flexibility and stiffness, playing a pivotal role in the increased mechanical strength. Cement hydration was retarded with the incorporation of the AMA copolymer, which was supported by the offset of the maximum hydration temperature. In contrast, in situ polymerization of monomers proved more effective than directly adding polymer in improving the fluidity and mechanical strength. We hope this strategy provides a new way to increase the crack resistance of cementitious materials and thereby contributes to their overall durability.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-06-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-024-02405-y.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141512933","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"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":"Impact of relative humidity on strength and microscopic pore structure of air lime-stabilized compressed earth","authors":"Yi Luo,&nbsp;Jieting Xu,&nbsp;Yongwei Huang,&nbsp;Pengpeng Ni,&nbsp;Wentao Li","doi":"10.1617/s11527-024-02411-0","DOIUrl":"10.1617/s11527-024-02411-0","url":null,"abstract":"<div><p>To investigate the impact of relative humidity on the mechanical properties and microscopic pore structure of air lime-stabilized compressed earth, unconfined compression strength (UCS), mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM) tests were conducted by varying the air lime content and relative humidity (RH) in compressed earth. The results revealed three typical failure modes in unconfined compression strength tests of lime-stabilized compressed earth. Both the unconfined compression strength and characteristic parameters of pore structure in lime-stabilized compressed earth exhibited a trend of initial increase, following by a decrease as the air lime content and relative humidity increased. At the microscopic level, the relative humidity and air lime content interacted with the changes in macro-level unconfined compression strength, and the increase of both could promote the lime hydration reactions, inhibiting the crack development. Considering the influence of relative humidity, mechanical performance, and economic benefit improvement, the recommended air lime content for high humidity and low humidity were 0–28% and 0–26%, respectively, offering valuable insights for the optimization and application of lime-stabilized compressed earth as a modern construction material for structural walls.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":null,"pages":null},"PeriodicalIF":3.4,"publicationDate":"2024-06-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-024-02411-0.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141512938","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}