Materials and Structures最新文献_第10页

Study on pore structure characteristics of circulating fluidized bed fly ash-based lightweight foamed filler based on X-ray computed tomography 基于x射线计算机断层成像的循环流化床粉煤灰轻质泡沫填料孔隙结构特征研究

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-07 DOI: 10.1617/s11527-024-02543-3

Jingchao Yang, Xingyi Wang, Xi Huang, Yansen Pei, Xiaoyuan Wang, Pengju Han, Xiaohong Bai

{"title":"Study on pore structure characteristics of circulating fluidized bed fly ash-based lightweight foamed filler based on X-ray computed tomography","authors":"Jingchao Yang, Xingyi Wang, Xi Huang, Yansen Pei, Xiaoyuan Wang, Pengju Han, Xiaohong Bai","doi":"10.1617/s11527-024-02543-3","DOIUrl":"10.1617/s11527-024-02543-3","url":null,"abstract":"<div>As the main solid waste of coal-fired power plants, circulating fluidized bed fly ash (CFBFA) has a huge emission, but its resource utilization in the field of construction materials is limited due to the generation of volume-expanding substances such as caliche and gypsum during the hydration process. A lightweight foamed filler (LFF) was prepared by taking CFBFA as the main material and mixing the foam produced by mechanical foaming to obtain a LFF, which utilizes its internal porosity to alleviate the expansion. The pore structure characteristic parameters such as porosity, homogeneity, pore size distribution, fractal dimension, sphericity, etc. of LFF specimens with different foam doping amounts were investigated from the three-dimensional level using X-CT tomography and other technical means. As the foam doping increases, the phenomena of foam rupture and dissipation and merger and fusion were frequent, which led to the deterioration of the consistency of the morphology of the pores in the LFF materials, and the inhomogeneity of the pore size and the average pore size increased, but the distribution of the pore size conformed to the log-normal distribution. The parameters of the LFF such as the porosity, the homogeneity of the pore distribution, the pore size, etc., were exponentially related to the compressive strength, and relationships of the sphericity with the pore size and homogeneity were quasi-linear.</div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142789176","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

Study on the shrinkage and restrained cracking of concrete with different surface curing methods 不同表面养护方法对混凝土收缩和抑制开裂的影响研究

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-07 DOI: 10.1617/s11527-024-02541-5

Jiahe Wang, Huajian Li, Yanbin Tan, Jiaxuan Wang, Yu Gao

{"title":"Study on the shrinkage and restrained cracking of concrete with different surface curing methods","authors":"Jiahe Wang, Huajian Li, Yanbin Tan, Jiaxuan Wang, Yu Gao","doi":"10.1617/s11527-024-02541-5","DOIUrl":"10.1617/s11527-024-02541-5","url":null,"abstract":"<div>The shrinkage of concrete cured with plastic film, controlled permeability formwork liner (CPFL) and moisture retention curing film (MRCF) were experimentally measured using the designed test devices. The compressive strain on the inner surface of steel ring was also studied during the steel ring restrained test. The correlation between the development of shrinkage and strain on the steel ring was analyzed from the perspective of concrete creep. The results show that: The surface curing method has a significant impact on the shrinkage deformation and restrained cracking process of concrete. The curing method should be adapted to the characteristics of the concrete body (w/b), otherwise there will be negative effects. CPFL can effectively reduce the drying shrinkage and the risk of restrained cracking of concrete by reducing the local w/b on the surface of concrete. It has a better effect on the low and medium strength grade concrete (C30 and C50), but has adverse effects on high-strength concrete (C80); MRCF can effectively reduce the shrinkage deformation and the risk of restrained cracking through the water supplement effect of the pre-absorbent materials. It has a better effect on the high-strength concrete, while its effect on low and medium strength grade concrete is relatively small. The creep capacity of concrete is closely related to the relative humidity level. It is stronger during the humidity saturation period, and weaker during the humidity decline period.</div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142789177","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

Early-age compressive behavior and stress–strain relationship of high -strength SSP-cement mortar 高强度ssp水泥砂浆早期抗压特性及应力-应变关系

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-06 DOI: 10.1617/s11527-024-02538-0

Guohua Sheng, Huiyu Tian, Shengji Jin, He Liu, Jingtao Xiu, Zheng Wei

{"title":"Early-age compressive behavior and stress–strain relationship of high -strength SSP-cement mortar","authors":"Guohua Sheng, Huiyu Tian, Shengji Jin, He Liu, Jingtao Xiu, Zheng Wei","doi":"10.1617/s11527-024-02538-0","DOIUrl":"10.1617/s11527-024-02538-0","url":null,"abstract":"<div>Steel slag powder-cement composite mortar (SSP-cement mortar), a low-carbon building material with industrial solid waste can effectively utilize SSP. However, the low hydration activity of SSP has a significant adverse effect on its early-age behavior. In this study, the early-age compressive behavior and stress–strain relationship of a high-strength SSP-cement mortar at the first curing period of 7 days were comprehensively studied. The mix proportion parameters include the replacement ratio of SSP Rs, cement strength grade fce, mesh of SSP ν, and water-binder ratio W/B. The curing temperature was set at T = 20℃ and T = 80℃. The results indicate that: firstly, at T = 20℃ and T = 80℃, the optimal values for cube compressive strength fcu are 71.2 MPa and 112.4 MPa, respectively, axial compressive strength fc are 50.1 MPa and 85.4 MPa, respectively. Secondly, with the increase of Rs, the fc, elastic modulus Ec, and toughness U, showed decreasing trends, the peak strain εcp shows an increasing trend. The trends have weakened at T = 80 ℃. With the increase of fce and ν, all the indexes (fc, εcp, Ec, and U) show an upward trend. With the increase of W/B, all the indexes show a decreasing trend and are more pronounced at T = 20℃. Finally, an early compressive stress–strain relationship of SSP-cement mortar was established. Based on the given parameters and curing temperatures, a compressive strength prediction model is provided to guide engineering applications.</div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142789239","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

Cementitious versus alkali-activated textile reinforced mortars for combined energy and seismic upgrade of masonry panels 水泥与碱活化纤维增强砂浆用于砌体面板的联合节能和抗震升级

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-06 DOI: 10.1617/s11527-024-02537-1

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

{"title":"Cementitious versus alkali-activated textile reinforced mortars for combined energy and seismic upgrade of masonry panels","authors":"Panagiotis Kapsalis, Paraskevi D. Askouni, Catherine G. Papanicolaou, Thanasis C. Triantafillou","doi":"10.1617/s11527-024-02537-1","DOIUrl":"10.1617/s11527-024-02537-1","url":null,"abstract":"<div>Masonry retrofitting systems combining seismic with energy upgrading features are increasingly gaining popularity in the scientific community during the past years since they simultaneously address two of the most pressing needs related to the existing building stock. This is commonly realized by applying textile reinforced mortar (TRM) overlays combined with thermal insulation boards on building envelopes. At the same time, the urge for eco-friendly and environmentally sustainable interventions calls for low-cement or even cement-free solutions. This study aims to combine these requirements by experimentally investigating an integrated seismic/energy retrofitting system that incorporates alkali-activated materials (AAM) based on industrial waste. The system is compared to a counterpart one comprising conventional cementitious materials. The relative position of the strengthening and the thermal insulation layers is yet another parameter of this study. The latter includes tests performed on retrofitted masonry specimens aiming to assess their mechanical performance in terms of masonry-to-overlay bond and flexural capacity. This is achieved by shear bond tests, and in-plane and out-of-plane bending tests, respectively. The results show that the replacement of cementitious binders by alkali-activated ones in TRM jackets is a promising alternative, eliminating cement consumption while ensuring comparable load bearing capacities with ‘conventional’ TRM systems. It is also indicated that the effectiveness of the AAM-based system is improved when the strengthening layer is applied externally, i.e., on top of the insulating boards. However, further research is needed for the optimization of the system’s mechanical and long-term performance.</div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142789241","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

Designing low-carbon ultra-high performance concrete with co-combustion ash of sewage sludge and rice husk 污水污泥与稻壳混烧灰低碳超高性能混凝土的设计

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-06 DOI: 10.1617/s11527-024-02535-3

Yan Xia, Daquan Shi, Yading Zhao, Jian Wang, Xiaobing Ma, Kunyang Yu, Huanyu Li, Lei Wang, Jianhua Yan

{"title":"Designing low-carbon ultra-high performance concrete with co-combustion ash of sewage sludge and rice husk","authors":"Yan Xia, Daquan Shi, Yading Zhao, Jian Wang, Xiaobing Ma, Kunyang Yu, Huanyu Li, Lei Wang, Jianhua Yan","doi":"10.1617/s11527-024-02535-3","DOIUrl":"10.1617/s11527-024-02535-3","url":null,"abstract":"<div>Ultra-high performance concrete (UHPC) exhibits excellent mechanical properties and durability. However, UHPC requires high content of cementitious materials, associating with high carbon footprints and economic cost. This study aimed to investigate the effects of co-combustion ash of sewage sludge and rice husk (CCA) in UHPC on the hydration mechanism, microstructure, mechanical properties and environmental impact. CCA-based UHPCs were designed by replacing cement or SF with CCA at replacement percentages of 5, 10, 15 and 20 wt%. The results indicated that CCA exhibited excellent pozzolanic reactivity. The maximum compressive strength of CCA-based UHPC exceeded 130 MPa. The total reaction degree of cementitious materials was increased by the incorporation of 10 wt% CCA, thus enhancing the strength development of UHPCs. Besides, additional C–A–S–H gels generated via the pozzolanic reaction of CCA, which increased the length of silicate chain of C–A–S–H gels and refined the pore structure of CCA-based UHPCs. Life-cycle assessment results revealed that replacing 20 wt% cement with CCA could reduce carbon emissions and fossil fuel depletion of UHPCs by 12% and 16%, respectively. Hence, the innovative approach of this study can recycle CCA to manufacture UHPCs with excellent performance and environmental benefits.</div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142789238","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

Depassivation of reinforcing steel due to accelerated-carbonation in limestone calcined clay cement concretes 石灰石煅烧粘土水泥混凝土中加速碳化引起的钢筋钝化

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-05 DOI: 10.1617/s11527-024-02485-w

Luis Felipe Salazar-Mayorga, Juan Lizarazo-Marriaga, Juan F. Arango-L

{"title":"Depassivation of reinforcing steel due to accelerated-carbonation in limestone calcined clay cement concretes","authors":"Luis Felipe Salazar-Mayorga, Juan Lizarazo-Marriaga, Juan F. Arango-L","doi":"10.1617/s11527-024-02485-w","DOIUrl":"10.1617/s11527-024-02485-w","url":null,"abstract":"<div>The effect of carbonation on corrosion of reinforced steel was investigated in five limestone and calcined clay (LC3) concrete mixtures designed adjusting their cement SO3 content. Accelerated carbonation tests were carried out according to BS EN 12390-12, while simultaneously the rebar corrosion activity was also monitored using electrochemical tests such as the linear polarization resistance (LPR). This paper reports on the methodology proposed to evaluate the reinforcement's response to corrosion while concrete carbonates. Results showed that LC3 concretes had a significant increase in the carbonation rate and demonstrated a Carbonation Index (CI) between 0.6–0.9, a parameter defined as the carbonation-depth to concrete-cover ratio, indicating the presence of active corrosion in the rebar, measured in terms of corrosion potential (Eoc) and current density (icorr). This condition represents an early stage of depassivation because the steel corrosion processes started before the carbonation front reached the rebar (CI < 1). This finding goes against traditional durability models in which the propagation stage begins when all cover concrete is already carbonated (CI = 1). Consequently, concrete using very high limestone and calcined clay replacement levels are much more vulnerable to accelerated carbonation.</div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142778397","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

Temperature dependence of the cohesive strength of asphalt binder in low- and medium-temperature zone and its mechanism 低、中温区沥青粘结剂黏结强度的温度依赖性及其机理

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-04 DOI: 10.1617/s11527-024-02539-z

Zhenfeng Song, Chuanfeng Zheng, Jing Zhao, Hanjun Li, Weidong Jin, Fuyv Wang, Chuanhao Lin, Haisong Luo

{"title":"Temperature dependence of the cohesive strength of asphalt binder in low- and medium-temperature zone and its mechanism","authors":"Zhenfeng Song, Chuanfeng Zheng, Jing Zhao, Hanjun Li, Weidong Jin, Fuyv Wang, Chuanhao Lin, Haisong Luo","doi":"10.1617/s11527-024-02539-z","DOIUrl":"10.1617/s11527-024-02539-z","url":null,"abstract":"<div>This study studied the changes in the bond strength of asphalt binders in medium and low temperature areas, focusing on the temperature-dependent mechanism that affects the bond strength of asphalt. The quantitative testing technology independently developed by the team was used to accurately measure the bond strength of three representative asphalt types (Type I, Type II, and Type III), and their change curves in the temperature range of 25 to − 35 °C were plotted. The experimental results show that within this temperature range, the bond strength of the three asphalts all showed significant peaks, and there were significant differences in the temperature and change rate when they appeared. These differences are mainly related to the differences in the asphalt component ratio and brittle temperature. The study also revealed the key influence of the asphalt brittle temperature on its low-temperature performance. The results show that by adjusting the asphalt composition to reduce the brittle temperature, its low-temperature bonding performance can be significantly improved. This study provides a theoretical basis for the selection of asphalt binders in road construction in cold areas, and proposes the importance of using brittle temperature as a screening indicator.</div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142778104","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

Mechanical and microscopic properties of low alkali sulfoaluminate and magnesium phosphate cement slurries modified recycled aggregate concrete 低碱硫铝酸盐和磷酸镁水泥浆改性再生骨料混凝土的力学和微观性能

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-03 DOI: 10.1617/s11527-024-02530-8

Jun Liu, Haoshen Zhao, Huazhong Ou, Zhongyu Lu, Baifa Zhang, Jianhe Xie

{"title":"Mechanical and microscopic properties of low alkali sulfoaluminate and magnesium phosphate cement slurries modified recycled aggregate concrete","authors":"Jun Liu, Haoshen Zhao, Huazhong Ou, Zhongyu Lu, Baifa Zhang, Jianhe Xie","doi":"10.1617/s11527-024-02530-8","DOIUrl":"10.1617/s11527-024-02530-8","url":null,"abstract":"<div>The use of recycled coarse aggregates (RCAs) in concrete often results in a decrease in mechanical properties due to the poor bonding performance between new and old interfaces. This study impregnated RCA with low-alkali sulfoaluminate (LASAC) and magnesium phosphate cement (MPC) to improve the mechanical properties of RCA, and the axial compressive strength and stress–strain characteristics of the recycled aggregate concrete (RAC) were performed. The experimental results showed that LASAC impregnation modification produced thick encapsulation layers and decreased the compressive strength. MPC modified RAC showed good mechanical properties. The thick encapsulation layer caused by LASAC weakened the bonding performance of the interfacial transition zones (ITZs), which led to mechanical properties decreased. MPC modification can effectively improve the ITZs between RCAs and new mortar. Scanning electron microscopy with energy dispersive X-ray spectrometry (SEM–EDS) results showed that LASAC slurries encapsulation layer loosened the ITZs of RCAs and new mortar. The hydration products of MPC acted on RCAs and the new mortar, mainly being clustered on the new mortar to densify the interface between RCAs and the new mortar, which increased the mechanical properties of RAC. Nanoindentation method was used to verify the microscopic mechanical properties between phases in RAC and support the experimental conclusion.</div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761793","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

Shear versus flexural bond tests of Textile-Reinforced Mortar applied to masonry substrates 用于砌筑基材的纺织增强砂浆的剪切与弯曲粘结试验

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-02 DOI: 10.1617/s11527-024-02529-1

Paraskevi D. Askouni, Catherine G. Papanicolaou

{"title":"Shear versus flexural bond tests of Textile-Reinforced Mortar applied to masonry substrates","authors":"Paraskevi D. Askouni, Catherine G. Papanicolaou","doi":"10.1617/s11527-024-02529-1","DOIUrl":"10.1617/s11527-024-02529-1","url":null,"abstract":"<div>The existing recommendations for the experimental investigation of the bond characteristics along interfaces comprising Textile-Reinforced Mortar (TRM) overlays and various types of substrates ignore the effect of out-of-plane stresses. This study investigates the in-plane and out-of-plane bond of two TRM systems with masonry substrate, employing the Single-Lap/Single-Prism (SL/SP) and the Modified Hinged Beam (MHB) set-up, respectively. The two systems shared the same cementitious matrix and comprised either Alkali Resistant (AR)-glass or carbon dry fibers textile (named GTRM and CTRM, respectively), while they had comparable axial rigidity. The failure mode of the specimens was due to slippage of the textile form within the matrix, regardless of the examined TRM system as well as the used set-up. Based on the comparison of the maximum textile axial stress obtained from the SL/SP and MHB tests for each TRM system, it was found that the normal stresses developed during bending enhanced the bond capacity of the CTRM system by almost 30%, whereas they had no apparent effect on the bond capacity of the GTRM system. The results of the current and previous related studies suggest that the bending stiffness, EfibIfib, of fibers is a parameter that could be correlated with the effect of the normal stress, in case dry fiber textiles are considered. Finally, it is concluded that for both adopted TRM systems the Cohesive Material Law calibrated based on the response curves obtained from the SL/SP and MHB tests is affected by the type of both the bond test and the textile’s fibers.</div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761729","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

Service life estimation, failure mechanisms, and specifications of galvanic anodes for corroding reinforced concrete structures 腐蚀钢筋混凝土结构用电阳极的使用寿命估计、失效机制和规范

IF 3.4 3区工程技术

Materials and Structures Pub Date : 2024-12-02 DOI: 10.1617/s11527-024-02536-2

Karthikeyan Manickam, Deepak K. Kamde, Radhakrishna G. Pillai

{"title":"Service life estimation, failure mechanisms, and specifications of galvanic anodes for corroding reinforced concrete structures","authors":"Karthikeyan Manickam, Deepak K. Kamde, Radhakrishna G. Pillai","doi":"10.1617/s11527-024-02536-2","DOIUrl":"10.1617/s11527-024-02536-2","url":null,"abstract":"<div>Cathodic protection using galvanic anodes is a proven technique to control or prevent corrosion of steel in reinforced concrete structures. However, huge variations have been observed in the properties of various galvanic anodes available in the concrete repair market and their resulting performance. This work assessed the performance of five commercially available galvanic anodes using an earlier developed Galvanic Anode Performance (GAP) test. In addition, a methodology to estimate the guaranteed minimum service life (SLmin) of galvanic anodes in concrete systems exposed to specific environmental conditions is developed. This methodology involves the determination of electrochemical capacity (i.e., total electrical charge drawn) of galvanic anodes and the corrosion rate of galvanic anodes using potentiostatic scans. It was found that the average SLmin of the five anodes tested under severe laboratory exposure conditions (Relative humidity of 100% and temperature of 25 ± 2 °C) ranged from about 3 months to 7 years – indicating huge variation in the quality of various galvanic anodes. The analysis of the physico-chemical characteristics of the encapsulating mortar of pristine and aged galvanic anodes showed that the average SLmin depends on the pH, activator content, total pore volume, and critical pore entry diameter of the encapsulating mortar and is irrespective of the mass of zinc. Also, the failure mechanisms of galvanic anodes observed during the GAP test are conceptualized and correlated to the properties of encapsulating mortar. Finally, a set of prescriptive and performance specifications for the selection of galvanic anode systems to achieve a target service life of repair is presented.</div>","PeriodicalId":691,"journal":{"name":"Materials and Structures","volume":"58 1","pages":""},"PeriodicalIF":3.4,"publicationDate":"2024-12-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142761730","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