T. A. Biyindi, Fabrice Kwefeu Mbakop, Eric Toumi, Belmondo Woumbeng Etonleu, Joseph Pondi
The present work deals with a comparative study of the physical-mechanical characteristics of different types of cement CEM II 42.5R produced and used in Cameroon. Indeed, the recent policy of integration and promotion of products in the sub-region has allowed some manufacturers (04) to settle in Cameroon and propose their products that characteristics are most often ignored by consumers. In order to handle this work correctly, we have conducted several tests on cements CEM II 42.5R of CIMENCAM and DANGOTE. These trials were carried out on fresh concrete, mortar, and also on a normalized cement paste. The present study mainly shows the specificities and the characteristics of CEM II 42.5R cement from other brands.
本文对喀麦隆生产和使用的不同类型CEM II 42.5R水泥的物理力学特性进行了比较研究。事实上，最近在该次区域的产品整合和推广政策已经允许一些制造商(04)在喀麦隆定居，并提出他们的产品特征最常被消费者忽视。为了正确处理这项工作，我们对CIMENCAM和DANGOTE的水泥CEM II 42.5R进行了多次测试。这些试验是在新混凝土、砂浆和正规整水泥浆上进行的。本研究主要展示了其他品牌CEM II 42.5R水泥的特性和特点。
{"title":"Comparative Physico Mechanical Study of Cements CEM II 42.5R in Cameroon: Case of DANGOTE and CIMENCAM","authors":"T. A. Biyindi, Fabrice Kwefeu Mbakop, Eric Toumi, Belmondo Woumbeng Etonleu, Joseph Pondi","doi":"10.4236/OJCE.2019.91002","DOIUrl":"https://doi.org/10.4236/OJCE.2019.91002","url":null,"abstract":"The present work deals with a comparative study of the physical-mechanical characteristics of different types of cement CEM II 42.5R produced and used in Cameroon. Indeed, the recent policy of integration and promotion of products in the sub-region has allowed some manufacturers (04) to settle in Cameroon and propose their products that characteristics are most often ignored by consumers. In order to handle this work correctly, we have conducted several tests on cements CEM II 42.5R of CIMENCAM and DANGOTE. These trials were carried out on fresh concrete, mortar, and also on a normalized cement paste. The present study mainly shows the specificities and the characteristics of CEM II 42.5R cement from other brands.","PeriodicalId":302856,"journal":{"name":"Open Journal of Civil Engineering","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127211006","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, the effect of substituting boron compounds with glycol-based grinding aids to the compressive strength performances of cement was investigated. Monoethylene glycol (MEG) and diethylene glycol (DEG) were used as glycol-based grinding aids, and anhydrous borax and boric acid were used as boron compounds in the tests. CEM I type cement production was carried out with the addition of grinding aid mixtures to Portland clinker and some gypsum in the experiments. All produced cement samples were tested for Blaine fineness, xrf elemental analysis and 2, 7 and 28 days compressive strength tests. Test results of grinding aids of MEG and boron compounds mixture showed no increase in any age of compressive strengths performances related to MEG used itself. However, with the addition of boron compounds to DEG increased grinding aid performance at all ages (2, 7 and 28 days). Possible reasons for this increase could be borate esters formed with DEG and boric acid in a basic medium.
{"title":"Effects of Adding Boron Compounds to Glycol Based Grinding Aids on Cement Compressive Strengths Performance","authors":"Murat Çallı, E. Pehlivan","doi":"10.4236/ojce.2019.91003","DOIUrl":"https://doi.org/10.4236/ojce.2019.91003","url":null,"abstract":"In this study, the effect of substituting boron compounds with glycol-based grinding aids to the compressive strength performances of cement was investigated. Monoethylene glycol (MEG) and diethylene glycol (DEG) were used as glycol-based grinding aids, and anhydrous borax and boric acid were used as boron compounds in the tests. CEM I type cement production was carried out with the addition of grinding aid mixtures to Portland clinker and some gypsum in the experiments. All produced cement samples were tested for Blaine fineness, xrf elemental analysis and 2, 7 and 28 days compressive strength tests. Test results of grinding aids of MEG and boron compounds mixture showed no increase in any age of compressive strengths performances related to MEG used itself. However, with the addition of boron compounds to DEG increased grinding aid performance at all ages (2, 7 and 28 days). Possible reasons for this increase could be borate esters formed with DEG and boric acid in a basic medium.","PeriodicalId":302856,"journal":{"name":"Open Journal of Civil Engineering","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2019-02-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122119683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Various studies have been conducted in the past by researchers who have proposed diverse solutions to control the premature degradation noted on flexible pavements. It turns out that the binder content remains a parameter so far not mastered and its optimization remains an imperative to produce a quality mix capable of meeting the technical and economic requirements sought in a formulation study. This article mainly aimed to optimize the hydrocarbon binder content of a 0/14 granular class semi-granular bituminous concrete using the Marshall and Duriez method. In the first part of the study, the different constituents were characterized according to the standards in force. The second allowed to describe the methodology used to determine the mixture and calculated the theoretical binder content. A theoretical mixture, entering the reference zone was defined at first. Following the characterization of the mixture in the laboratory, the granulometry curve of the mixture was inserted into the reference zone. This mixture was then preserved for the rest of the study. Then, it was theoretically determined bitumen contents ranging from 5.13% to 5.75% for wealth modules ranging from 3.3% to 3.7%. Thus, the Marshall method was used to characterize the performance of the mixture as a function of the binder content. The results obtained led to the selection of two grades of binders 5.13% and 5.28% for the study of water resistance using the Duriez method. On the basis of the results obtained on the Duriez test, the mixture with a binder content of 5.28% satisfies a good part of the criteria selected. This content corresponds to a wealth module of 3.4%.
{"title":"Optimization of the Bitumen Content of a Basaltic Semi-Granular Bituminous Concrete","authors":"Souleymane Mbengue, D. Sow, I. Cissé","doi":"10.4236/ojce.2018.84032","DOIUrl":"https://doi.org/10.4236/ojce.2018.84032","url":null,"abstract":"Various studies have been conducted in the past by researchers who have proposed diverse solutions to control the premature degradation noted on flexible pavements. It turns out that the binder content remains a parameter so far not mastered and its optimization remains an imperative to produce a quality mix capable of meeting the technical and economic requirements sought in a formulation study. This article mainly aimed to optimize the hydrocarbon binder content of a 0/14 granular class semi-granular bituminous concrete using the Marshall and Duriez method. In the first part of the study, the different constituents were characterized according to the standards in force. The second allowed to describe the methodology used to determine the mixture and calculated the theoretical binder content. A theoretical mixture, entering the reference zone was defined at first. Following the characterization of the mixture in the laboratory, the granulometry curve of the mixture was inserted into the reference zone. This mixture was then preserved for the rest of the study. Then, it was theoretically determined bitumen contents ranging from 5.13% to 5.75% for wealth modules ranging from 3.3% to 3.7%. Thus, the Marshall method was used to characterize the performance of the mixture as a function of the binder content. The results obtained led to the selection of two grades of binders 5.13% and 5.28% for the study of water resistance using the Duriez method. On the basis of the results obtained on the Duriez test, the mixture with a binder content of 5.28% satisfies a good part of the criteria selected. This content corresponds to a wealth module of 3.4%.","PeriodicalId":302856,"journal":{"name":"Open Journal of Civil Engineering","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-12-03","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132033626","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study dynamic analysis of Soil Structure Interaction (SSI) effect on multi story reinforced concrete (RC) frame founded on soft soil (flexible base) is made and compared with fixed base. Two model 2D RC frames with 7 and 12 story are selected for analysis. Winkler Spring and half space direct method models are used for flexible base for the frames founded on two types of soft soils with shear velocity Vs < 150 m/s Asper Seismic Codes of Chinese GB50011-2010 Soil IV and Ethiopian ES8-2015 soil D. The frames are subjected to strong ground motion matched to response spectrums of soft soil of Chinese GB50011-2010 and Ethiopian ES8-2015 for linear time history analysis. The dynamic analysis result shows Spring and Fixed base mass participation 90% reaches in 2 or 3 modes but in direct method 11 to 30 modes for story 12 and 7 respectively. However, both flexible base models have bigger fundamental period of vibration and inter story drift but smaller base shear than fixed base. In addition, within the flexible base models the inter-story drift, second order effect (P-Δ) and Story shear distribution are different along the height of frames. The spring model shows larger Story drift and second order effect (P-Δ) at the bottom of Story for both soft soils types. On the other hand, half space direct method model indicates value reverse to spring model; it gives bigger Story drift and P-Δ effect in the top stories than fixed base. Finally, this study concludes that base shear reduction due to SSI may not be always beneficial. Because the gravity load is constant in both fixed and flexible bases that cause bigger P-Δ effect at the bottom stories due to increase, inter story drift and decrease story shear in flexible base.
{"title":"Dynamic Analysis of Soil Structure Interaction Effect on Multi Story RC Frame","authors":"Hailu Getachew Kabtamu, Gang Peng, Denghong Chen","doi":"10.4236/OJCE.2018.84030","DOIUrl":"https://doi.org/10.4236/OJCE.2018.84030","url":null,"abstract":"In this study dynamic analysis of Soil Structure Interaction (SSI) effect on multi story reinforced concrete (RC) frame founded on soft soil (flexible base) is made and compared with fixed base. Two model 2D RC frames with 7 and 12 story are selected for analysis. Winkler Spring and half space direct method models are used for flexible base for the frames founded on two types of soft soils with shear velocity Vs < 150 m/s Asper Seismic Codes of Chinese GB50011-2010 Soil IV and Ethiopian ES8-2015 soil D. The frames are subjected to strong ground motion matched to response spectrums of soft soil of Chinese GB50011-2010 and Ethiopian ES8-2015 for linear time history analysis. The dynamic analysis result shows Spring and Fixed base mass participation 90% reaches in 2 or 3 modes but in direct method 11 to 30 modes for story 12 and 7 respectively. However, both flexible base models have bigger fundamental period of vibration and inter story drift but smaller base shear than fixed base. In addition, within the flexible base models the inter-story drift, second order effect (P-Δ) and Story shear distribution are different along the height of frames. The spring model shows larger Story drift and second order effect (P-Δ) at the bottom of Story for both soft soils types. On the other hand, half space direct method model indicates value reverse to spring model; it gives bigger Story drift and P-Δ effect in the top stories than fixed base. Finally, this study concludes that base shear reduction due to SSI may not be always beneficial. Because the gravity load is constant in both fixed and flexible bases that cause bigger P-Δ effect at the bottom stories due to increase, inter story drift and decrease story shear in flexible base.","PeriodicalId":302856,"journal":{"name":"Open Journal of Civil Engineering","volume":"110 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114259031","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this study, the effect of iron powder (Fe2O3) on the compressive strength, tensile strength, workability, and porosity of the binary blended concrete were experimentally investigated. For this purpose, Portland cement was partially replaced by 1.5%, 2.5%, 3.5%, and 5% by weighing of iron powder. The amount of water-binder-ratio was considered constant. The workability of the fresh composite concrete was determined using cone Abrams method; mechanical properties were determined included compressive and tensile strengths at 7, 14, and 28 days and durability evaluated by water absorption and permeable porosity. It was observed that the compressive and tensile strengths change with the replacement of iron powder by up to 5%. However, the maximum improvement was gained at 2.5 wt% for compressive strength and 1.5 wt% for tensile strength. The workability of the fresh mixtures decreased when iron powder amount increased. It was observed that the porosity decreased respectively by 21.88% and 26.77% at 1.5 wt% and 2.5 wt% replacement. Moreover, this present study shows the importance and benefits to improve concrete properties by using micro-particles materials.
{"title":"Effect of Iron Powder (Fe 2 O 3 ) on Strength, Workability, and Porosity of the Binary Blended Concrete","authors":"Moussa Anan Largeau, R. Mutuku, J. Thuo","doi":"10.4236/OJCE.2018.84029","DOIUrl":"https://doi.org/10.4236/OJCE.2018.84029","url":null,"abstract":"In this study, the effect of iron powder (Fe2O3) on the compressive strength, tensile strength, workability, and porosity of the binary blended concrete were experimentally investigated. For this purpose, Portland cement was partially replaced by 1.5%, 2.5%, 3.5%, and 5% by weighing of iron powder. The amount of water-binder-ratio was considered constant. The workability of the fresh composite concrete was determined using cone Abrams method; mechanical properties were determined included compressive and tensile strengths at 7, 14, and 28 days and durability evaluated by water absorption and permeable porosity. It was observed that the compressive and tensile strengths change with the replacement of iron powder by up to 5%. However, the maximum improvement was gained at 2.5 wt% for compressive strength and 1.5 wt% for tensile strength. The workability of the fresh mixtures decreased when iron powder amount increased. It was observed that the porosity decreased respectively by 21.88% and 26.77% at 1.5 wt% and 2.5 wt% replacement. Moreover, this present study shows the importance and benefits to improve concrete properties by using micro-particles materials.","PeriodicalId":302856,"journal":{"name":"Open Journal of Civil Engineering","volume":"577 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-11-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131847353","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper describes the installation and management of the monitoring system of the “Our Lady of Tears Shrine” in Syracuse, whose dome is an imposing r.c. and prestressed r.c. structure of about 22,000 ton that was seismically isolated by flat sliding devices with hysteretic dampers. The monitoring system, representing an upgrading and improvement of an old system never made working, has some innovative features, because it allows to manage with the same dedicated hardware and software both the slow (thermal variations, relative humidity, wind direction and velocity) and the fast acquisitions (dynamic vibrations by wind and earthquake). The monitoring system was inserted among those structures maintained and controlled by the Seismic Observatory of Structures of the National Department of Civil Protection. Some records of low magnitude earthquakes allowed to validate the correct behaviour of the whole structure, as well as to make a dynamic identification of the complex construction and to calibrate a detailed finite element model of the Sanctuary, thus predicting isolators’ behaviour under design earthquake.
{"title":"Monitoring and Identification of the Seismically Isolated “Our Lady of Tears” Shrine in Syracuse","authors":"D. Losanno, M. Spizzuoco","doi":"10.4236/ojce.2018.84028","DOIUrl":"https://doi.org/10.4236/ojce.2018.84028","url":null,"abstract":"This paper describes the installation and management of the monitoring system of the “Our Lady of Tears Shrine” in Syracuse, whose dome is an imposing r.c. and prestressed r.c. structure of about 22,000 ton that was seismically isolated by flat sliding devices with hysteretic dampers. The monitoring system, representing an upgrading and improvement of an old system never made working, has some innovative features, because it allows to manage with the same dedicated hardware and software both the slow (thermal variations, relative humidity, wind direction and velocity) and the fast acquisitions (dynamic vibrations by wind and earthquake). The monitoring system was inserted among those structures maintained and controlled by the Seismic Observatory of Structures of the National Department of Civil Protection. Some records of low magnitude earthquakes allowed to validate the correct behaviour of the whole structure, as well as to make a dynamic identification of the complex construction and to calibrate a detailed finite element model of the Sanctuary, thus predicting isolators’ behaviour under design earthquake.","PeriodicalId":302856,"journal":{"name":"Open Journal of Civil Engineering","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134554942","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This experimental research is focused on the effect of concrete made by incorporating lime treated Palm Kernel Shell (PKS) & Sugarcane Bagasse Ash (SCBA) as partial replacements of coarse aggregates and Ordinary Portland Cement (OPC) respectively. An experimental analysis for concrete grade 30 with a mix design ratio of 1:1.97:3.71 of cement:fine aggregates:coarse aggregates with a constant water to cement ratio of 0.5, was used. Physical tests such as workability on fresh concrete and water absorption on hardened concrete of each batch were carried out. Mechanical tests like compressive strength and split tensile strength were carried out on hardened concrete cubes (100 mm × 100 mm × 100 mm) and cylinders (100 mm × 200 mm) at 7 and 28 days. The experimental results obtained in this study indicate the possibility of using up 15% of lime treated PKS and 10% of SCBA for production of structural concrete.
本实验研究的重点是用石灰处理的棕榈仁壳(PKS)和甘蔗甘蔗渣灰(SCBA)分别部分替代粗骨料和普通硅酸盐水泥(OPC)制成混凝土的效果。采用水泥:细骨料:粗骨料的设计配合比为1:1.97:3.71、水灰比恒定为0.5的30级混凝土试验分析。对每批混凝土进行了新拌混凝土和易性、硬化混凝土吸水性等物理试验。在第7天和第28天分别对硬化混凝土立方体(100 mm × 100 mm × 100 mm)和圆柱体(100 mm × 200 mm)进行抗压强度和劈裂抗拉强度等力学试验。本研究的实验结果表明，使用15%石灰处理的PKS和10%的SCBA生产结构混凝土的可能性。
{"title":"Experimental Investigation of Lime Treated Palm Kernel Shell and Sugarcane Bagasse Ash as Partial Replacement of Coarse Aggregate and Cement Respectively in Concrete","authors":"Mahfouz O. A. Djima, G. Mang’uriu, J. Mwero","doi":"10.4236/ojce.2018.84027","DOIUrl":"https://doi.org/10.4236/ojce.2018.84027","url":null,"abstract":"This experimental research is focused on the effect of concrete made by incorporating lime treated Palm Kernel Shell (PKS) & Sugarcane Bagasse Ash (SCBA) as partial replacements of coarse aggregates and Ordinary Portland Cement (OPC) respectively. An experimental analysis for concrete grade 30 with a mix design ratio of 1:1.97:3.71 of cement:fine aggregates:coarse aggregates with a constant water to cement ratio of 0.5, was used. Physical tests such as workability on fresh concrete and water absorption on hardened concrete of each batch were carried out. Mechanical tests like compressive strength and split tensile strength were carried out on hardened concrete cubes (100 mm × 100 mm × 100 mm) and cylinders (100 mm × 200 mm) at 7 and 28 days. The experimental results obtained in this study indicate the possibility of using up 15% of lime treated PKS and 10% of SCBA for production of structural concrete.","PeriodicalId":302856,"journal":{"name":"Open Journal of Civil Engineering","volume":"08 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131169603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Repair and reinformcement of aged civil steel structures is one of the important issues for maintaining and using them for a long term. For repair and reinforcement of deteriorated civil steel structures due to fatigue and corrosion, patch plate reinforcement is widely applied. Bolting is generally used because of easy quality control and many construction achievements. However, bolting has downsides including holes made and weight increase. Welding is considered to overcome these demerits but in reality the application of welding is unsatisfactory due to the possibility of fatigue crack occurring from the welded part. In this study, a patch plate strengthening system of welded joint assisted with bonding has been proposed. The compressive behaviors of weld-bond jointed specimen were investigated by a series of experiments and FE analysis. It was confirmed that use of welding and bonding was effective to enhance compressive strength of specimen, due to better load-carrying capacity of patch plate compared with sole use of welding.
{"title":"Compressive Behavior of Steel Members Reinforced by Patch Plate with Welding and Bonding","authors":"Xiaoyan Liu, M. Hirohata","doi":"10.4236/OJCE.2018.84026","DOIUrl":"https://doi.org/10.4236/OJCE.2018.84026","url":null,"abstract":"Repair and reinformcement of aged civil steel structures is one of the important issues for maintaining and using them for a long term. For repair and reinforcement of deteriorated civil steel structures due to fatigue and corrosion, patch plate reinforcement is widely applied. Bolting is generally used because of easy quality control and many construction achievements. However, bolting has downsides including holes made and weight increase. Welding is considered to overcome these demerits but in reality the application of welding is unsatisfactory due to the possibility of fatigue crack occurring from the welded part. In this study, a patch plate strengthening system of welded joint assisted with bonding has been proposed. The compressive behaviors of weld-bond jointed specimen were investigated by a series of experiments and FE analysis. It was confirmed that use of welding and bonding was effective to enhance compressive strength of specimen, due to better load-carrying capacity of patch plate compared with sole use of welding.","PeriodicalId":302856,"journal":{"name":"Open Journal of Civil Engineering","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123700524","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Akhil Subedi, Gopal S. Bhandari, Paribesh Parajuli
This paper focuses on the seismic performance of mountainous railway bridges having different pier type i.e. rectangular hollow piers and solid piers. The piers used were of same materials and inertial properties. For this, 3-D FEM models of these bridges were created by ANSYS 15.0. For seismic assessment, Response Spectrum and Dynamic Time-History Analysis methods were adopted. Different types of earthquake waves used were Elcentro, Wenchuan and Nepal earthquakes, all normalized to 0.3 g Peak Ground Acceleration (PGA). The study concluded that even though the hollow pier bridges are susceptible to large displacements, its dealing with internal forces is remarkable compared to solid pier bridges.
{"title":"Seismic Performances of Mountainous Continuous Rigid Frame Solid and Hollow Pier Railway Bridges","authors":"Akhil Subedi, Gopal S. Bhandari, Paribesh Parajuli","doi":"10.4236/ojce.2018.84035","DOIUrl":"https://doi.org/10.4236/ojce.2018.84035","url":null,"abstract":"This paper focuses on the seismic performance of mountainous railway bridges having different pier type i.e. rectangular hollow piers and solid piers. The piers used were of same materials and inertial properties. For this, 3-D FEM models of these bridges were created by ANSYS 15.0. For seismic assessment, Response Spectrum and Dynamic Time-History Analysis methods were adopted. Different types of earthquake waves used were Elcentro, Wenchuan and Nepal earthquakes, all normalized to 0.3 g Peak Ground Acceleration (PGA). The study concluded that even though the hollow pier bridges are susceptible to large displacements, its dealing with internal forces is remarkable compared to solid pier bridges.","PeriodicalId":302856,"journal":{"name":"Open Journal of Civil Engineering","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115608264","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In this paper, the evaluation of the mechanical and hygro-thermal properties of expanded polystyrene-sanded lightweight concrete (EPSLC) was examined. Evaluated are the mechanical properties in terms of density; and the hygro-thermal property using water absorption (capillary absorption and total immersion) as measures. The research used 30% volume of EPS to replace natural coarse aggregate to produce a lightweight concrete, which is expected to be economical, serviceable and meet the required standards for lightweight concretes. The concrete bulk and oven dry densities were obtained as 1789 KN/m3 and 1674 kg/m3 respectively, while the total water and capillary water absorption increases with time of suction. The high rate of water absorption at the early periods of the test has corresponding capillary coefficient of steep slope within the same period. The relationship between the variables Q the water absorption per unit area of the specimen and K the capillary coefficient, is that as the water absorption gets higher, so does the capillary coefficient and the percentage of the variation is expressed by the correlation coefficient R2. Therefore, the values of R2 as depicted in the graphs shows a high percentage of variation. The moisture capacity is 6.9%. All the laboratory tests were, conducted in accordance with standard codes of practice. The significance of the research is that innovative technology is employed to modify and improve processes in construction industry, thus, enhancing sustainable environmental, management of industrial waste, and cheaper and economic construction. With the 30% replacement of coarse aggregate, the density and water absorption properties of concrete produced are within acceptable limits. Therefore, EPS can be used to produce lightweight concrete that will perform the required function at this level of replacement.
{"title":"An Evaluation of the Water Absorption and Density Properties of Expanded Polystyrene Sanded Concrete","authors":"J. Abah, E. Ndububa, E. Ikpe","doi":"10.4236/ojce.2018.84037","DOIUrl":"https://doi.org/10.4236/ojce.2018.84037","url":null,"abstract":"In this paper, the evaluation of the mechanical and hygro-thermal properties of expanded polystyrene-sanded lightweight concrete (EPSLC) was examined. Evaluated are the mechanical properties in terms of density; and the hygro-thermal property using water absorption (capillary absorption and total immersion) as measures. The research used 30% volume of EPS to replace natural coarse aggregate to produce a lightweight concrete, which is expected to be economical, serviceable and meet the required standards for lightweight concretes. The concrete bulk and oven dry densities were obtained as 1789 KN/m3 and 1674 kg/m3 respectively, while the total water and capillary water absorption increases with time of suction. The high rate of water absorption at the early periods of the test has corresponding capillary coefficient of steep slope within the same period. The relationship between the variables Q the water absorption per unit area of the specimen and K the capillary coefficient, is that as the water absorption gets higher, so does the capillary coefficient and the percentage of the variation is expressed by the correlation coefficient R2. Therefore, the values of R2 as depicted in the graphs shows a high percentage of variation. The moisture capacity is 6.9%. All the laboratory tests were, conducted in accordance with standard codes of practice. The significance of the research is that innovative technology is employed to modify and improve processes in construction industry, thus, enhancing sustainable environmental, management of industrial waste, and cheaper and economic construction. With the 30% replacement of coarse aggregate, the density and water absorption properties of concrete produced are within acceptable limits. Therefore, EPS can be used to produce lightweight concrete that will perform the required function at this level of replacement.","PeriodicalId":302856,"journal":{"name":"Open Journal of Civil Engineering","volume":"351 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-10-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133911123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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