Materials and Structures最新文献_第2页

RILEM TC 275-HDB round-robin tests and proposals: moisture buffer value of vegetal concrete

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2025-01-14 DOI: 10.1617/s11527-024-02550-4

Florence Collet, Stijn Mertens, Paulina Faria

{"title":"RILEM TC 275-HDB round-robin tests and proposals: moisture buffer value of vegetal concrete","authors":"Florence Collet, Stijn Mertens, Paulina Faria","doi":"10.1617/s11527-024-02550-4","DOIUrl":"10.1617/s11527-024-02550-4","url":null,"abstract":"<div><p>Previous studies on the moisture buffering characterization of hemp concrete have shown some discrepancies and difficulties for comparison. The aim of this paper is to raise warning points and define a robust protocol for Moisture Buffer Value (MBV) measurement of vegetal concrete. The applicability of the NORDTEST protocol was assessed by two round robin tests (RRT) on an industrial hemp concrete. Seven laboratories participated to the RRT. The first RRT specified a method for the conditioning of specimens prior to the MBV test, without added recommendation. Based on the shortcomings of the first RRT, a second RRT was performed with additional recommendations. For the test, the specimens should be representative of in-situ ones regarding exchange surface and orientation versus moisture flux. RRT2 confirmed that the exchange surface finishing widely affects the MBV results. Moreover, it underlined the effect of air velocity and the least efficiency of climate chambers with Peltier technology. The results obtained following this more detailed protocol were comparable between laboratories, suggesting their robustness to assess MBV of vegetal concrete.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-01-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142976514","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}

引用次数: 0

Experimental and analytical study of RC columns strengthened with cementitious grout under small eccentric compression

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2025-01-13 DOI: 10.1617/s11527-025-02568-2

Gang Peng, Xiaopeng Hu, Ditao Niu, Shuai Zhong

{"title":"Experimental and analytical study of RC columns strengthened with cementitious grout under small eccentric compression","authors":"Gang Peng, Xiaopeng Hu, Ditao Niu, Shuai Zhong","doi":"10.1617/s11527-025-02568-2","DOIUrl":"10.1617/s11527-025-02568-2","url":null,"abstract":"<div><p>In this paper, compressive tests of RC columns strengthened with cementitious grout under small eccentric compression were performed to explore the strengthening response. The effects of reinforcement position and thickness on the failure modes, bearing capacity, ductility, and stiffness of the columns were analyzed. Results indicated that the bearing capacity and corresponding deflection of the columns increased gradually with the increase of reinforcement thickness, and the enhancements in bearing capacity of compressive-side strengthened columns were obviously greater than that of the tensile-side strengthened columns. Simultaneously, the ductility coefficients presented a decreasing trend with the increase of reinforcement thickness while the influence of reinforcement position on the ductility coefficients of the columns did not show consistent variations. Moreover, the stiffness degradation rate of the compressive-side strengthened columns was slower than that of tensile-side strengthened columns, and the stiffness degradation rate of the columns decreased with the increase of the reinforcement thickness. Thereafter, a rational calculation method for predicting the bearing capacity of the columns strengthened with cementitious grout under small eccentric compression was proposed.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-01-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142976421","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}

引用次数: 0

Correction: Cementitious versus alkali-activated textile reinforced mortars for combined energy and seismic upgrade of masonry panels

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2025-01-13 DOI: 10.1617/s11527-024-02561-1

Panagiotis Kapsalis, Paraskevi D. Askouni, Catherine G. Papanicolaou, Thanasis C. Triantafillou

引用次数: 0

Effect of prior in-plane damage on the out-of-plane behavior of adobe block walls

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2025-01-10 DOI: 10.1617/s11527-024-02563-z

Daxing Chen, Kang Yuan, Yin Liu, Zihao Li

{"title":"Effect of prior in-plane damage on the out-of-plane behavior of adobe block walls","authors":"Daxing Chen, Kang Yuan, Yin Liu, Zihao Li","doi":"10.1617/s11527-024-02563-z","DOIUrl":"10.1617/s11527-024-02563-z","url":null,"abstract":"<div><p>Adobe block walls are prone to out-of-plane collapse under seismic actions. Current research on the in-plane seismic performance of adobe block walls is relatively comprehensive, while studies on out-of-plane seismic performance and the relationship between in-plane and out-of-plane seismic performance are lacking. This paper conducted in-plane cyclic loading tests and out-of-plane airbag monotonic loading tests on adobe block walls, obtaining the out-of-plane failure modes, load-bearing capacity, deformation characteristics, under different in-plane damage conditions. Based on this, theoretical analysis was used to derive a method for calculating the load-bearing capacity of adobe block walls in the out-of-plane direction and establish an empirical relationship between in-plane damage severity and out-of-plane load-bearing capacity. The research findings indicate that adobe block walls experience bending tensile failure along the bottom horizontal mortar joint when subjected to uniformly distributed out-of-plane loads. The difference between the cracking load and peak load is relatively small. The wall displaces linearly along the height direction, with the maximum out-of-plane displacement occurring at the top of the wall. There is a clear interaction between in-plane damage severity and out-of-plane strength of the wall. As the in-plane damage severity increases, the out-of-plane load-bearing capacity of the wall decreases by 6.25% to 34.87%.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142941201","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}

引用次数: 0

Thermal, chemical, and rheological characterization of bio-asphalt prepared using sugarcane molasses

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2025-01-10 DOI: 10.1617/s11527-024-02549-x

Dheeraj Mehta, Nikhil Saboo

{"title":"Thermal, chemical, and rheological characterization of bio-asphalt prepared using sugarcane molasses","authors":"Dheeraj Mehta, Nikhil Saboo","doi":"10.1617/s11527-024-02549-x","DOIUrl":"10.1617/s11527-024-02549-x","url":null,"abstract":"<div><p>Asphalt binder replacement with bio-materials (bio-asphalt) has recently gained significant attention. Bio-asphalt serves as a sustainable avenue and is currently being researched for reducing the dependency on asphalt binder. This work is aimed towards understanding the thermal, morphological, chemical, and rheological behaviour of asphalt binder partially replaced with sugarcane molasses (SM). The optimum dosage for partial replacement was arrived as 30% (by weight of asphalt binder). Two base binders (VG 40 and VG 30) along with five SM sources were used to prepare the bio-asphalts. The thermal stability evaluated using thermogravimetric analysis revealed that bio-asphalts have acceptable thermal resistance withstanding temperature up to 200 °C. Fluorescence microscopy exhibited that SM particles were uniformly dispersed in the base binder, rendering a stable structure. Through chemical analysis (asphaltene–maltene ratio) it was found that the asphaltene percentage marginally increases after the addition of SM. Rheological characterization comprised of multiple stress creep recovery and linear amplitude sweep tests. Test results indicated that incorporation of SM resulted in lower non-recoverable creep compliance (<i>J</i><sub>nr</sub>), decreased permanent strain, and similar/slightly higher percent recovery (% R). The fatigue life of bio-asphalts improved due to the formulation of compounds capable of imparting elasticity to the bio-asphalts.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-01-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-024-02549-x.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142941202","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}

引用次数: 0

Impact of loading protocol on the repair efficiency of heat-damaged concrete beams with SNSM CFRP ropes

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2025-01-09 DOI: 10.1617/s11527-025-02569-1

Rami H. Haddad, Rawan S. Obeidat

{"title":"Impact of loading protocol on the repair efficiency of heat-damaged concrete beams with SNSM CFRP ropes","authors":"Rami H. Haddad, Rawan S. Obeidat","doi":"10.1617/s11527-025-02569-1","DOIUrl":"10.1617/s11527-025-02569-1","url":null,"abstract":"<div><p>The influence of static-load distribution and symmetry on the flexural performance of reinforced concrete beams, strengthened/repaired using side near-surface-mounted (SNSM) carbon fiber reinforced polymer (CFRP) ropes with parabolic and straight profiles is investigated. For this, eighteen reinforced concrete beams (150 × 250 × 1600 mm) were fabricated using a ready-mix concrete of 35 MPa strength grade before cured in wet burlap for 28 days. Nine beams were exposed to an elevated temperature at 450 °C for three hours, while the remaining ones were left in laboratory air, as controls. Six specimens from each group were retrofitted using SNSM of straight and parabolic profiles then tested with references ones under four- and six-point symmetrical and six-point asymmetrical loadings with load response versus deflection and strain in SNSM ropes acquired. Furthermore, cracking initiation and propagation leading to failure was monitored and reported. Generally, the study revealed that the mechanical performance of the concrete beams was influenced by the loading regime as well as by the rope profile (straight, parabolic) as well as heat-damage. The performance factor (PF), computed based on strength and deformability performances, varied from 5.4 to 7.9 for strengthened compared to 10.9–16.3 for repaired and heat-damaged specimens. Furthermore, all strengthened/repaired beams failed by concrete-cover separation following the sudden rupture of the SNSM CFRP ropes except for that repaired with a straight profile of SNSM CFRP rope and subjected to asymmetrical loading.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142939075","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}

引用次数: 0

Enhancement in stability of air bubbles in mortar at fresh state with different SCMs

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2025-01-09 DOI: 10.1617/s11527-024-02566-w

Qian Jiang, Cheng Yu, Qian Zhang

{"title":"Enhancement in stability of air bubbles in mortar at fresh state with different SCMs","authors":"Qian Jiang, Cheng Yu, Qian Zhang","doi":"10.1617/s11527-024-02566-w","DOIUrl":"10.1617/s11527-024-02566-w","url":null,"abstract":"<div><p>The stability of air bubbles is a critical factor in determining the performance of concrete. This study investigated the influence of various supplementary cementing materials (SCMs), with a 20% replacement of cement by weight, on the stability of foam in solutions and air bubbles in fresh mortars. Air bubble size distributions were measured using an air void analyzer and X-ray computed tomography at two intervals: from 5 to 60 min and from 60 to 180 min after the mixture was prepared. The results demonstrated that the number of small bubbles decreased while the number of large bubbles increased over time, with the most significant changes occurring within the initial 60 min. The results of the wettability tests were combined with those from the X-ray diffraction (XRD) analysis to identify a correlation between the stability of air bubbles and the wetting angle of the SCMs. It was observed that the contact angle of the SCMs approached 90° in cases where the air bubbles exhibited increased stability. The XRD patterns revealed significant differences in the mineral compositions between the bubble shells and the screened pastes from fresh mortar. The presence of a higher concentration of SCMs and hydration products on the bubble shells, compared to the paste, was identified as a potential reason for the observed differences in bubble stability. The utilization of specific SCMs has the potential to enhance bubble stability, in addition to the use of chemical admixtures.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142939282","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}

引用次数: 0

Evaluation of connectors' influence on the interface behaviour between concrete layers

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2025-01-09 DOI: 10.1617/s11527-024-02553-1

Juozas Masėnas, Juozas Valivonis

{"title":"Evaluation of connectors' influence on the interface behaviour between concrete layers","authors":"Juozas Masėnas, Juozas Valivonis","doi":"10.1617/s11527-024-02553-1","DOIUrl":"10.1617/s11527-024-02553-1","url":null,"abstract":"<div><p>The behavior of concrete interfaces cast at different times is influenced by many variables, including material characteristics, interface surface preparation, interface geometry and many more. The performance of such interfaces is not yet fully understood and is particularly challenging to predict. This paper presents and discusses the results of 17 experimental push-off tests, which varied in interface types and connector arrangements. Three types of interface connector arrangements were tested and compared: one perpendicular to the interface and two lattice girder configurations. Interfaces with lattice girder connectors exhibited greater adhesion resistance. Among these, one specific lattice girder arrangement demonstrated the highest resistance to shear following adhesion failure. A second type of lattice girder arrangement was responsible for the lowest interface crack width. When the perpendicular interface connector arrangement was used, the widest interface crack was observed. The experimental specimens also featured different interface surface types: smooth and shear key interfaces. The shear key interface achieved the highest overall shear capacity. Additionally, a novel theoretical model was employed to predict interface behavior up to considerable slippage. The impact of differential shrinkage on the adhesion resistance of the interface was demonstrated using theoretical shrinkage and interface behavior results.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1617/s11527-024-02553-1.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142939076","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}

引用次数: 0

Investigation of the seepage property of a concrete fracture in a marine environment

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2025-01-09 DOI: 10.1617/s11527-025-02570-8

Yun Chen, Shuaishuai Miao, Mingfeng Xu, Guowei Ma

{"title":"Investigation of the seepage property of a concrete fracture in a marine environment","authors":"Yun Chen, Shuaishuai Miao, Mingfeng Xu, Guowei Ma","doi":"10.1617/s11527-025-02570-8","DOIUrl":"10.1617/s11527-025-02570-8","url":null,"abstract":"<div><p>Concrete fractures, commonly considered as dominant flow channels in a submarine immersed tunnel at the stage of damage, greatly influence the structural long-term service performance in a marine environment. This study investigates the coupled process of the chemical interaction and the fluid flow behavior in concrete fractures, based on seepage tests of specimens experiencing immersion processes in an artificial marine environment with a depth of 50 m below sea level. The salt ion ratio used in the immersion tests comes from the field data of the actual marine environment where locates the immersed tunnel of the Hong Kong–Zhuhai–Macao Bridge immersed tunnel. Seventy cylindrical concrete specimens with dimensions of 25 mm × 50 mm are prepared, and each specimen is split to obtain a rough-walled fracture. The specimens are evenly divided into seven groups with different immersion periods, and the variation of the equivalent hydraulic apertures as well as the reaction products after the immersion tests of the concrete fractures are investigated. The surface morphology and composition analyses along the fracture surfaces indicate that the chemical reaction products during the immersion process are gypsum and ettringite. Furthermore, the variation results of the hydraulic properties indicate that the permeability of concrete fractures gradually reduces as the immersion period increases, and the equivalent hydraulic aperture varies less for the concrete fracture with relatively high roughness. An equivalent seepage model for a concrete fracture in a marine environment is then established to evaluate the equivalent hydraulic aperture considering the immersion environment and the fracture geometry, which provides a theoretical basis for analyzing seepage properties of concrete fractures in a marine environment and the long-term service performance of a submarine immersed tunnel.Kindly check and confirm whether the corresponding affiliation is correctly identified.The corrsponding affiliation is correcly identified.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2025-01-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142939281","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}

引用次数: 0

Cellulose nanofibrils in pervious concrete: improving mechanical properties and durability

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-26 DOI: 10.1617/s11527-024-02559-9

Jingchen Li, Weidong Cao, Ziqi Yan, Zunhao Zhan, Yingjian Li

{"title":"Cellulose nanofibrils in pervious concrete: improving mechanical properties and durability","authors":"Jingchen Li, Weidong Cao, Ziqi Yan, Zunhao Zhan, Yingjian Li","doi":"10.1617/s11527-024-02559-9","DOIUrl":"10.1617/s11527-024-02559-9","url":null,"abstract":"<div><p>Pervious concrete (PC), commonly used in urban pavement, is known for its high permeability, which contributes to mitigating the urban heat island effect. However, the low strength and durability of PC limit its use. The objective of this study is to improve mechanical properties and durability of PC by adding cellulose nanofibrils (CNFs). The results showed that CNFs significantly enhanced compressive strength, flexural strength, and salt frost resistance, with optimal performance at 0.15% CNF. At this concentration, compressive and flexural strengths increased by 26.5% and 25.8%, respectively, despite a slight reduction of 10.2% in permeability. CNFs also improved resistance to salt-induced freeze–thaw cycles, reducing spalling and maintaining a higher value of the dynamic modulus of elasticity, particularly at 0.1% and 0.15% dosages. Scanning electron microscope (SEM) analyses revealed that CNFs create a denser, more uniform network of hydrated products, enhancing microstructure and interfacial bonding. This study confirms that CNFs can significantly enhance the mechanical properties and durability of PC.</p></div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142889736","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}

引用次数: 0