The purpose of this study was to evaluate the performance of gravel impact compaction piers system (GICPs) in improving a 3.5m thick loose silty sand in a multilayer coastal soil system located in Bushehr, Iran. The liquefiable sandy soil layer was layered on clay layers with moderate to very stiff consistency and below the engineering embankment layer with a thickness of 1.8 m. Implementation of gravel impact compaction piers is a new generation of aggregate piers. Gravel impact compaction piers were used to improve the liquefiable soil layers and to increase the bearing capacity and reduce subgrade settlement to withstand surface infrastructures. The process of making gravel impact compaction piers in a triangular or square-patterned grid was created using three types of special mandrels and feeding and compacting the gravels in the cavity in several stages without removing the soil from the cavities. The experience gained in this case study showed that artificial liquefiable was created immediately after the construction of these piers in a limited area and the soil became unstable. After about 11-14 days, the soil stabilized rapidly. The results of the standard penetration test in the matrix soil around the piers showed that the amount of (N1)60 in compacted soils was in the range of 21-30 and on average 15 times the amount of (1-3) in the initial soil. Also, the relative density of the initial soil was increased from 25% to 75% after soil improvement. Accordingly, by relying merely on the compaction properties of the piers and without relying on other primary soil remediation factors, such as piers drainage and soil texture change, the safety factor of the improved soil is 1.7-1.95 times the minimum required according to the two risk levels in the design.
{"title":"Gravel impact compaction piers as a method of soil improvement","authors":"B. Niroumand, H. Niroumand","doi":"10.7764/rdlc.21.3.539","DOIUrl":"https://doi.org/10.7764/rdlc.21.3.539","url":null,"abstract":"The purpose of this study was to evaluate the performance of gravel impact compaction piers system (GICPs) in improving a 3.5m thick loose silty sand in a multilayer coastal soil system located in Bushehr, Iran. The liquefiable sandy soil layer was layered on clay layers with moderate to very stiff consistency and below the engineering embankment layer with a thickness of 1.8 m. Implementation of gravel impact compaction piers is a new generation of aggregate piers. Gravel impact compaction piers were used to improve the liquefiable soil layers and to increase the bearing capacity and reduce subgrade settlement to withstand surface infrastructures. The process of making gravel impact compaction piers in a triangular or square-patterned grid was created using three types of special mandrels and feeding and compacting the gravels in the cavity in several stages without removing the soil from the cavities. The experience gained in this case study showed that artificial liquefiable was created immediately after the construction of these piers in a limited area and the soil became unstable. After about 11-14 days, the soil stabilized rapidly. The results of the standard penetration test in the matrix soil around the piers showed that the amount of (N1)60 in compacted soils was in the range of 21-30 and on average 15 times the amount of (1-3) in the initial soil. Also, the relative density of the initial soil was increased from 25% to 75% after soil improvement. Accordingly, by relying merely on the compaction properties of the piers and without relying on other primary soil remediation factors, such as piers drainage and soil texture change, the safety factor of the improved soil is 1.7-1.95 times the minimum required according to the two risk levels in the design.","PeriodicalId":54473,"journal":{"name":"Revista de la Construccion","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71305939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper studies 123 hydraulic bridge failures in China from 1998 to 2018. The geographic distribution, age distribution, bridge type distribution, time distribution and the hydraulic bridge failure causes are analyzed. Six typical failure cases of hydraulic bridges are analyzed in detail. 100 hydraulic bridge failures occurred in southern China so hydraulic bridge failures are much more common in this area. The average service life of these bridges is 28.9 years. The beam bridge accounts for the largest proportion of hydraulic bridge failure because 71 (57.7%) beam bridges were destroyed by flood. Hydraulic bridge failure mainly occurred between 2009 and 2014, which was related to the impact of the Wenchuan earthquake. The incidents major causes include unexpected flood, earthquake, old bridge, over sand exploitation, low awareness of hydraulic bridge damage, extreme morphology of the river, etc. There are both natural factors and man-made factors. These results show that three aspects should be paid attention to: (1) unexpected flood; (2) appropriate bridge type; and (3) extreme morphology of the river.
{"title":"Recent hydraulic bridge failures in China: review and discussion","authors":"S. Qin","doi":"10.7764/rdlc.21.2.193","DOIUrl":"https://doi.org/10.7764/rdlc.21.2.193","url":null,"abstract":"This paper studies 123 hydraulic bridge failures in China from 1998 to 2018. The geographic distribution, age distribution, bridge type distribution, time distribution and the hydraulic bridge failure causes are analyzed. Six typical failure cases of hydraulic bridges are analyzed in detail. 100 hydraulic bridge failures occurred in southern China so hydraulic bridge failures are much more common in this area. The average service life of these bridges is 28.9 years. The beam bridge accounts for the largest proportion of hydraulic bridge failure because 71 (57.7%) beam bridges were destroyed by flood. Hydraulic bridge failure mainly occurred between 2009 and 2014, which was related to the impact of the Wenchuan earthquake. The incidents major causes include unexpected flood, earthquake, old bridge, over sand exploitation, low awareness of hydraulic bridge damage, extreme morphology of the river, etc. There are both natural factors and man-made factors. These results show that three aspects should be paid attention to: (1) unexpected flood; (2) appropriate bridge type; and (3) extreme morphology of the river.","PeriodicalId":54473,"journal":{"name":"Revista de la Construccion","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71304973","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The objective of this study was to improve the performance of flexible pavement through suitable aggregate gradation. Thus, initially, the dynamic modulus of asphalt mixtures |E*| for different aggregate gradations were predicted, and suitable aggregate gradation was determined. Then the performance of three different pavement structures for two aggregate gradations (Mid and Suitable), using AASHTOWare Pavement ME Design 2.5. 5, were evaluated for local conditions of Izmir, Turkey. The analysis result revealed that using suitable values compared to middle values increased the |E*| and improved the rutting and fatigue resistance of all pavement structures for any traffic levels. The output of this study can be used as a guide for hot mixed asphalt mix design and pavement design based on Mechanistic-Empirical Pavement Design Guide as well.
本研究的目的是通过合适的骨料级配来改善柔性路面的性能。因此，初步预测了不同骨料级配下沥青混合料的动态模量|E*|，并确定了合适的骨料级配。然后使用AASHTOWare pavement ME Design 2.5对两种骨料级配(中等和适宜)下的三种不同路面结构进行性能分析。5，对土耳其伊兹密尔的当地情况进行了评估。分析结果表明，与中间值相比，选择合适的值可提高所有路面结构在任何交通水平下的车辙性能和抗疲劳性能。本文的研究成果可为热拌沥青混合料的设计和基于力学-经验路面设计指南的路面设计提供指导。
{"title":"Improving flexible pavement performance through suitable aggregate gradation","authors":"Mohammad Razeq Shakhan, A. Topal, B. Sengoz","doi":"10.7764/rdlc.21.2.295","DOIUrl":"https://doi.org/10.7764/rdlc.21.2.295","url":null,"abstract":"The objective of this study was to improve the performance of flexible pavement through suitable aggregate gradation. Thus, initially, the dynamic modulus of asphalt mixtures |E*| for different aggregate gradations were predicted, and suitable aggregate gradation was determined. Then the performance of three different pavement structures for two aggregate gradations (Mid and Suitable), using AASHTOWare Pavement ME Design 2.5. 5, were evaluated for local conditions of Izmir, Turkey. The analysis result revealed that using suitable values compared to middle values increased the |E*| and improved the rutting and fatigue resistance of all pavement structures for any traffic levels. The output of this study can be used as a guide for hot mixed asphalt mix design and pavement design based on Mechanistic-Empirical Pavement Design Guide as well.","PeriodicalId":54473,"journal":{"name":"Revista de la Construccion","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71305339","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Concrete decomposing the organic compounds on because of natural or anthropogenic contaminating sources with photocatalysis existing in its structure is called self-cleaning concrete. In this study, the self-cleaning concrete with industrial waste has been searched from the point of mechanical and physical characteristics. Fly ash, blast furnace slag and sepiolite materials has been used as industrial waste in concrete. Titanium dioxide (TiO2) has been used as photocatalysis material. Specimens with the dimensions 15×15×15 cm were produced using 0 %, 10 %, 20 % and 30 % industrial wastes and 0 %, 1 %, 3 %, 5 % TiO2 by weight instead of cement. Compressive strength, unit weight, and ultrasonic pulse velocity tests were performed on the specimens after 28 days standard cure. Rhodamine-B test in Italian UNI 11259 standard and additional Phenantroquinone test have been performed as self-cleaning test. XRF test also has been made on some of the samples for the chemical analysis. The best photocatalysis performance has showed in the concrete including 5 % TiO2. Test results show that 10 % use of industrial wastes in self-cleaning concrete production is recommended from the point of economic and environmental benefits
{"title":"Effect of industrial wastes on self-cleaning properties of concrete containing anatase-TiO2","authors":"Serdal Ünal, M. Canbaz","doi":"10.7764/rdlc.21.3.493","DOIUrl":"https://doi.org/10.7764/rdlc.21.3.493","url":null,"abstract":"Concrete decomposing the organic compounds on because of natural or anthropogenic contaminating sources with photocatalysis existing in its structure is called self-cleaning concrete. In this study, the self-cleaning concrete with industrial waste has been searched from the point of mechanical and physical characteristics. Fly ash, blast furnace slag and sepiolite materials has been used as industrial waste in concrete. Titanium dioxide (TiO2) has been used as photocatalysis material. Specimens with the dimensions 15×15×15 cm were produced using 0 %, 10 %, 20 % and 30 % industrial wastes and 0 %, 1 %, 3 %, 5 % TiO2 by weight instead of cement. Compressive strength, unit weight, and ultrasonic pulse velocity tests were performed on the specimens after 28 days standard cure. Rhodamine-B test in Italian UNI 11259 standard and additional Phenantroquinone test have been performed as self-cleaning test. XRF test also has been made on some of the samples for the chemical analysis. The best photocatalysis performance has showed in the concrete including 5 % TiO2. Test results show that 10 % use of industrial wastes in self-cleaning concrete production is recommended from the point of economic and environmental benefits","PeriodicalId":54473,"journal":{"name":"Revista de la Construccion","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71305892","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, the dynamic behavior of one of the prominent structures in Istanbul, Üsküdar Observation Tower (UOT) has been investigated. The structural system of the tower is formed by a reinforced concrete circular tube having 2.8 meters outside diameter with a 40 centimeter thickness. By referring to the ground level, it starts from -18.2 meter due to five basement stories around the tower and its height is 44 meters. Two reinforced concrete floors were partially hanged over at 36 meter and 40 meter in height. The tower has an independent structural system from the ground level but a non-structural cladding assembly connects it to an adjacent building in the complex. With the mentioned structural features, Ambient Vibration Survey (AVS) was utilized to obtain the dynamic characteristics of UOT by Peak Picking (PP) method. The obtained dynamic properties were discussed with the peculiarities of UOT. While the performed analysis revealed the ineffectiveness of the adjacent building and the underground stories in the dynamic behavior of UOT, the torsion action of the floors has been noted. A numerical model has also been constructed to obtain the dynamic characteristics of UOT by Finite Element Analysis (FEA). The model calibration required to increase the code-based modulus of elasticity of the concrete by 23% for pairing the experimental and numerical dynamic properties. The reasons of the increase and the correlation between AVS and FEA were discussed.
{"title":"Experimental and numerical dynamic identification in an RC tower","authors":"F. Aras, Tarık Tufan","doi":"10.7764/rdlc.21.3.555","DOIUrl":"https://doi.org/10.7764/rdlc.21.3.555","url":null,"abstract":"In this study, the dynamic behavior of one of the prominent structures in Istanbul, Üsküdar Observation Tower (UOT) has been investigated. The structural system of the tower is formed by a reinforced concrete circular tube having 2.8 meters outside diameter with a 40 centimeter thickness. By referring to the ground level, it starts from -18.2 meter due to five basement stories around the tower and its height is 44 meters. Two reinforced concrete floors were partially hanged over at 36 meter and 40 meter in height. The tower has an independent structural system from the ground level but a non-structural cladding assembly connects it to an adjacent building in the complex. With the mentioned structural features, Ambient Vibration Survey (AVS) was utilized to obtain the dynamic characteristics of UOT by Peak Picking (PP) method. The obtained dynamic properties were discussed with the peculiarities of UOT. While the performed analysis revealed the ineffectiveness of the adjacent building and the underground stories in the dynamic behavior of UOT, the torsion action of the floors has been noted. A numerical model has also been constructed to obtain the dynamic characteristics of UOT by Finite Element Analysis (FEA). The model calibration required to increase the code-based modulus of elasticity of the concrete by 23% for pairing the experimental and numerical dynamic properties. The reasons of the increase and the correlation between AVS and FEA were discussed.","PeriodicalId":54473,"journal":{"name":"Revista de la Construccion","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71305947","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Morales-Segura, D. Caballol, Á. Raposo, Francisco Gil-Carrillo
The reverberation time was tested in a reverberation chamber with three acoustic absorbent materials commonly used in construction. The tests were performed with different materials, setups, and back air layers. Results have been compared with those where this material is placed as a single piece. Analyzing obtained data, a linear regression model is established to predict, for certain frequencies, the alteration produced in the reverberation time. So, knowing the absorption coefficient of an amount of material, it is possible to predict the different absorption coefficients placing the same material in separated pieces and different distances from room walls. The model has been validated and tested, which demonstrates its accuracy, it has also been proved to be applicable to a wide variety of materials. It becomes a simple predictive tool that allows to estimate in situ the alteration in the reverberation time due to the separation of the absorbent material in patches.
{"title":"Acoustic absorption prediction by placing absorbent material in separate pieces with or without back air layer","authors":"M. Morales-Segura, D. Caballol, Á. Raposo, Francisco Gil-Carrillo","doi":"10.7764/rdlc.21.1.156","DOIUrl":"https://doi.org/10.7764/rdlc.21.1.156","url":null,"abstract":"The reverberation time was tested in a reverberation chamber with three acoustic absorbent materials commonly used in construction. The tests were performed with different materials, setups, and back air layers. Results have been compared with those where this material is placed as a single piece. Analyzing obtained data, a linear regression model is established to predict, for certain frequencies, the alteration produced in the reverberation time. So, knowing the absorption coefficient of an amount of material, it is possible to predict the different absorption coefficients placing the same material in separated pieces and different distances from room walls. The model has been validated and tested, which demonstrates its accuracy, it has also been proved to be applicable to a wide variety of materials. It becomes a simple predictive tool that allows to estimate in situ the alteration in the reverberation time due to the separation of the absorbent material in patches.","PeriodicalId":54473,"journal":{"name":"Revista de la Construccion","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71304552","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Karaca, Kamil Tekin, Süleyman Bahadır Keskin, Özlem Kasap Keskin
In this study, the effect of particle size of quartz sand on the fresh and hardened properties of engineered cementitious composites (ECC) was investigated. For this purpose, three ECC mixtures that are identical except for the gradation of quartz sands used in their composition were designed. One of the mixtures includes a combination of quartz sands with amounts determined by the Andreasen and Andersen particle size optimization model while the remaining two have a finer and a coarser gradation. In the fresh state, mini slump, mini V-funnel and bleeding tests were applied, and rheological parameters were determined according to Bingham and modified Bingham models by using a rotational viscometer. In the hardened state, flexural strengths, mid-span deflections and numbers of microcracks formed under flexural loading were determined at 7 and 28 days. It was observed that the particle size optimization of the quartz sand can provide a balance between flow and bleeding characteristics of ECC mixtures. Although a reduction in flexural strength occurred at both ages in the optimized ECC mixture, the deflection capacity and the crack formation capacity under loading were significantly increased, reaching a deflection value of over 10 mm with at least 11 cracks formed during the test. As a result, it was revealed that particle size optimization can yield a mixture with the highest ductility without compromising the workability of ECC.
{"title":"Effects of particle size optimization of quartz sand on rheology and ductility of engineered cementitious composites","authors":"H. Karaca, Kamil Tekin, Süleyman Bahadır Keskin, Özlem Kasap Keskin","doi":"10.7764/rdlc.21.2.447","DOIUrl":"https://doi.org/10.7764/rdlc.21.2.447","url":null,"abstract":"In this study, the effect of particle size of quartz sand on the fresh and hardened properties of engineered cementitious composites (ECC) was investigated. For this purpose, three ECC mixtures that are identical except for the gradation of quartz sands used in their composition were designed. One of the mixtures includes a combination of quartz sands with amounts determined by the Andreasen and Andersen particle size optimization model while the remaining two have a finer and a coarser gradation. In the fresh state, mini slump, mini V-funnel and bleeding tests were applied, and rheological parameters were determined according to Bingham and modified Bingham models by using a rotational viscometer. In the hardened state, flexural strengths, mid-span deflections and numbers of microcracks formed under flexural loading were determined at 7 and 28 days. It was observed that the particle size optimization of the quartz sand can provide a balance between flow and bleeding characteristics of ECC mixtures. Although a reduction in flexural strength occurred at both ages in the optimized ECC mixture, the deflection capacity and the crack formation capacity under loading were significantly increased, reaching a deflection value of over 10 mm with at least 11 cracks formed during the test. As a result, it was revealed that particle size optimization can yield a mixture with the highest ductility without compromising the workability of ECC.","PeriodicalId":54473,"journal":{"name":"Revista de la Construccion","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71305473","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Transverse joint spacing is one of the fundamental input parameters in structural design of jointed plain concrete pavement (JPCP). It has to be determined considering many factors to produce a well-performing and cost-effective JPCP. In this study, a comprehensive evaluation of transverse joint spacing in JPCP was carried out based on the followings: (1) guidelines based on previous studies, the Federal Highway Administration and the American Concrete Pavement Association recommendations were summarized; (2) empirical and mechanistic-empirical (M-E) pavement design methodologies were reviewed; (3) current state highway agency practices in USA were surveyed as part of this study and the survey results were documented; (4) effects of joint spacing on JPCP performance were evaluated based on field observations; and (5) lastly, an economic analysis was performed to evaluate effects of joint spacing on life-cycle costs. This study demonstrated that a joint spacing between 15-18 ft (4.6-5.5 m) seems to be provide a safe zone for both performance and cost effectiveness.
{"title":"Comprehensive evaluation of transverse joint spacing in jointed plain concrete pavement","authors":"O. Kaya","doi":"10.7764/rdlc.21.3.618","DOIUrl":"https://doi.org/10.7764/rdlc.21.3.618","url":null,"abstract":"Transverse joint spacing is one of the fundamental input parameters in structural design of jointed plain concrete pavement (JPCP). It has to be determined considering many factors to produce a well-performing and cost-effective JPCP. In this study, a comprehensive evaluation of transverse joint spacing in JPCP was carried out based on the followings: (1) guidelines based on previous studies, the Federal Highway Administration and the American Concrete Pavement Association recommendations were summarized; (2) empirical and mechanistic-empirical (M-E) pavement design methodologies were reviewed; (3) current state highway agency practices in USA were surveyed as part of this study and the survey results were documented; (4) effects of joint spacing on JPCP performance were evaluated based on field observations; and (5) lastly, an economic analysis was performed to evaluate effects of joint spacing on life-cycle costs. This study demonstrated that a joint spacing between 15-18 ft (4.6-5.5 m) seems to be provide a safe zone for both performance and cost effectiveness.","PeriodicalId":54473,"journal":{"name":"Revista de la Construccion","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71305564","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the recent years, there has been increased in concern on shrinkage response of concrete systems as abundant cases of premature deterioration were reported. The major factors affecting the deterioration of a concrete system are quality, composition and the surrounding environment. In connection with this, the work concentrates on the study of long-term effects on materials used in the concrete (supplementary cementitious materials SCMs) such as fly ash, slag and silica fume as a blended concrete system. To carry out the experimental work, nine concrete mixes were designed for varying proportions of SCMs and w/b. Evolution of compressive strength, elastic modulus, shrinkage and selected durability parameters were tested under a controlled laboratory condition. Based on the work, it was found that the inclusion of fly ash, slag and silica fume on the concrete systems enhance the compressive strength in long-term, also the shrinkage response of the ternary systems shows a substantial reduction in the measured strain. Durability performance like chloride penetration and sorptivity had a better performance in comparison with the conventional concrete systems.
{"title":"Prediction of strength and shrinkage of ternary blended concrete with fly ash, slag and silica fume","authors":"T. Sakthivel, K. Arulraj","doi":"10.7764/rdlc.21.3.669","DOIUrl":"https://doi.org/10.7764/rdlc.21.3.669","url":null,"abstract":"In the recent years, there has been increased in concern on shrinkage response of concrete systems as abundant cases of premature deterioration were reported. The major factors affecting the deterioration of a concrete system are quality, composition and the surrounding environment. In connection with this, the work concentrates on the study of long-term effects on materials used in the concrete (supplementary cementitious materials SCMs) such as fly ash, slag and silica fume as a blended concrete system. To carry out the experimental work, nine concrete mixes were designed for varying proportions of SCMs and w/b. Evolution of compressive strength, elastic modulus, shrinkage and selected durability parameters were tested under a controlled laboratory condition. Based on the work, it was found that the inclusion of fly ash, slag and silica fume on the concrete systems enhance the compressive strength in long-term, also the shrinkage response of the ternary systems shows a substantial reduction in the measured strain. Durability performance like chloride penetration and sorptivity had a better performance in comparison with the conventional concrete systems.","PeriodicalId":54473,"journal":{"name":"Revista de la Construccion","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71305661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
P. Loganathan, R. Mohanraj, S. Senthilkumar, K. Yuvaraj
In the presented paper, an attempt has been made to first find the permeability of the Euphorbia tortilis cactus (ETC) concrete by the water permeability method and infiltration method. After that, the flexural strength of the ETC RC beam wrapped with AFRP kelvar 149 is carried out by a 2-point load test. This research aimed to develop a more durable, flexural, and sustainable beam under static load. Based on the state-of-the-art information available in the literature, 3-layer Kelvar 149 AFRP is considered as a laminate to solve the deflections of the ETC beam. In this project, RCC beams were strengthened by ETC and aramid FRP sheets. Novel results are obtained by different layers and patterns of Aramid FRP sheets. Based on the investigation 3-layers Kelvar 149 perform well than a normal concrete beam. As no result based on hydraulic conductivity and drying shrinkage of a beam with AFRP laminates are available in the literature, the obtained results are validated with the finite element method (ABAQUS) under static load conditions.
{"title":"Mechanical performance of ETC RC beam with U-framed AFRP laminates under a static load condition","authors":"P. Loganathan, R. Mohanraj, S. Senthilkumar, K. Yuvaraj","doi":"10.7764/rdlc.21.3.678","DOIUrl":"https://doi.org/10.7764/rdlc.21.3.678","url":null,"abstract":"In the presented paper, an attempt has been made to first find the permeability of the Euphorbia tortilis cactus (ETC) concrete by the water permeability method and infiltration method. After that, the flexural strength of the ETC RC beam wrapped with AFRP kelvar 149 is carried out by a 2-point load test. This research aimed to develop a more durable, flexural, and sustainable beam under static load. Based on the state-of-the-art information available in the literature, 3-layer Kelvar 149 AFRP is considered as a laminate to solve the deflections of the ETC beam. In this project, RCC beams were strengthened by ETC and aramid FRP sheets. Novel results are obtained by different layers and patterns of Aramid FRP sheets. Based on the investigation 3-layers Kelvar 149 perform well than a normal concrete beam. As no result based on hydraulic conductivity and drying shrinkage of a beam with AFRP laminates are available in the literature, the obtained results are validated with the finite element method (ABAQUS) under static load conditions.","PeriodicalId":54473,"journal":{"name":"Revista de la Construccion","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2022-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"71305669","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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