Journal of Civil, Construction and Environmental Engineering最新文献

{"title":"Mechanical Properties of Foundation Concrete Exposed to a Swampy Area for a Prolonged Period","authors":"Nsahlai Leonard Nyuykongi, Y. Emmanuel, N. Bilong, Blaise Ngwem Bayiha, M. Kuma","doi":"10.11648/J.JCCEE.20210605.11","DOIUrl":"https://doi.org/10.11648/J.JCCEE.20210605.11","url":null,"abstract":"A total of 24 concrete samples of nominal dimensions 300mm x 150mm x 100mm each were produced for laboratory testing using six cement dosages of 150 Kg/m3, 200 Kg/m3, 250 Kg/m3, 300 Kg/m3, 350, and 400 Kg/m3. Samples were buried at a swampy area with a moisture content of 67.38% for 56days, 84days, 112days and 196days. For concrete dosed at 400 Kg/m3, compressive strengths of 20.8MPa, 19MPa, 16.5MPa, and 12.7MPa were recorded for 56days, 84days, 112days, and 196days, respectively. The modulus of elasticity for the concrete dosed at 400 Kg/m3 is 29741.38 MPa, and the Poisson ratio is 0.177. The bulk modulus for concrete dosed at 400 Kg/m3 was found to be 15346.43MPa and the shear modulus was 12634.4 MPa. Concrete dosed at 150Kg/m3 recorded a Von Mises stress of 15.407MPa, while concrete dosed at 400 Kg/m3 recorded a higher von Mises stress of 21.984 MPa. The Von Mises stresses were far greater than most of the average uni-axial failure stresses. The maximum distortion energy for concrete dosed at 150 Kg/m3 is 9.028 KJ/m3, while that dosed at 400 Kg/m3 has a distortion energy of 6.067 KJ/m3. Other mechanical properties such as the strains, principal stresses, and failure angles were also assessed. The general trend of the analyses revealed that prolonged exposure of concrete to a humid environment has an adverse effect on the engineering performance of concrete.","PeriodicalId":262934,"journal":{"name":"Journal of Civil, Construction and Environmental Engineering","volume":"283 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-10-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121137956","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}

{"title":"Study of Eccentric and Buckling-Restrained Bracing Systems Used in Frames","authors":"A. Bahrami","doi":"10.11648/J.JCCEE.20210604.13","DOIUrl":"https://doi.org/10.11648/J.JCCEE.20210604.13","url":null,"abstract":"The present paper studies eccentric braces (EBs) and buckling-restrained braces (BRBs) used in steel frames. The eccentrically braced frames (EBFs) and buckling-restrained braced frames (BRBFs) that have respectively employed the EBs and BRBs are considered with different types of links as shear, moment-shear and moment links depending on their link length which is an important factor in the design of the EBFs and BRBFs. The BRB consists of a steel core and its surrounding steel tube filled with concrete. The concrete confinement prevents buckling of the steel core. The analysed EBFs and BRBFs by the finite element software ABAQUS under earthquake records are taken into account. Effects of the links of the EBFs and BRBFs on the performance of the frames are discussed. The results uncover that most of the lateral displacements of the EBFs and BRBFs having the shear link are smaller than their counterparts having the moment-shear and moment links, whilst, all the base shear capacities of the former are the greatest. However, majority of the EBFs and BRBFs with the moment link dissipate less energy than their counterparts with the shear and moment-shear links, whereas, most of the link rotations of the former are smaller than the latter. In addition, the BRBFs generally demonstrate better performance than their EBF counterparts.","PeriodicalId":262934,"journal":{"name":"Journal of Civil, Construction and Environmental Engineering","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128746388","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}

{"title":"Assessment of the Semi-Adiabatic Temperature Rise of Mass Concrete Containing Bagasse Ash","authors":"Amanuel Bersisa, Adil Zekaria","doi":"10.11648/J.JCCEE.20210604.12","DOIUrl":"https://doi.org/10.11648/J.JCCEE.20210604.12","url":null,"abstract":"Previous studies show that pozzolan materials are a wise choice for retarding significant heat in mass concrete placements. This research aims at studying the early age thermal property of concrete containing bagasse ash under different ambient temperatures. Moreover, the compressive strength of concrete specimens with varying ratios of the mix is assessed. Semi-adiabatic temperature rise data of four different concrete mixtures (containing pure Portland cement, 6.5%, 13%, and 20% dosage of bagasse ash by volume) are determined. Concrete specimens of size 30cm*30cm*40cm were cast and insulated using Styrofoam. The temperature measurement is taken at three different locations for every 30 minutes of interval. The influence of ambient temperature on specimens' early age thermal response is studied using a temperature chamber capable of simulating 25.15°C, 35.54°C, and 43.77°C average ambient temperatures. The results indicated that bagasse ash could replace the cement up to an optimum replacement level of 10 percent even if an early age strength drop is observed. The experiment revealed that the bagasse ash in the concrete mixture shift the temperature rise-time profile, reduces the total heat of hydration, and decreases the thermal gradient in the specimens. The peak temperature gauge of all mixes elevated as the ambient temperature increased, but mixtures containing bagasse ash show a slower heat liberation rate relative to the control group. The study proves pozzolan reaction is slow, releasing heat over a long period and not taking place early. It has merit in a massive concrete placement where cooling can lead to cracking following a significant temperature rise.","PeriodicalId":262934,"journal":{"name":"Journal of Civil, Construction and Environmental Engineering","volume":"59 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115094453","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}

{"title":"Embankment Dam Seepage and Slope Stability Analysis: The Case of Arjo-dedessa Dam, Ethiopia","authors":"Ayansa Gamachu Aga","doi":"10.11648/J.JCCEE.20210604.11","DOIUrl":"https://doi.org/10.11648/J.JCCEE.20210604.11","url":null,"abstract":"Dams have one of the greatest significant roles in operating water resources. Seepage and slope stability failures cause completely failure of embankment dams. Dam disasters not only hazard community safety, they also can cost our economy millions of dollars in compensations. The study area is found in Oromia regional state between East Wollega and Bunno Bedele Zone. The dam is located on Dedessa River, tributary of Blue Nile River. Analysis of seepage quantity was done by Darcy’s phreatic line, and SEEP/W software model for both homogeneous and zoned dam. The expected quantity of seepage estimated with the SEEP/W software model analysis that includes foundation seepage is 6.6*10-6m3/sec. Slope stability study is to contribute to the safe and economic design of upstream and downstream slope of the dam. The factory of safety obtained by Morgenstern-Price method for end construction is (FOS=1.99), for steady state (FOS=2.03) and rapid drawdown (FOS=2.91). However, at the design document shell material hadn’t been designed properly. Finally the paper concluded that the likely corrective measures for seepage controls are impermeable blanket, grouting, and the downstream slope miscarriage by eliminating the pathetic zone and seal with like graded quantifiable, regular repairs and shield the downstream slope with grasses.","PeriodicalId":262934,"journal":{"name":"Journal of Civil, Construction and Environmental Engineering","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-08-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121659465","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}

{"title":"Hydrological Response of Land Use Land Cover Change on Stream Flow of Anger Watershed, Blue Nile Basin, Ethiopia","authors":"Getachew Rabo","doi":"10.11648/J.JCCEE.20210603.12","DOIUrl":"https://doi.org/10.11648/J.JCCEE.20210603.12","url":null,"abstract":"Stream flow of Anger watershed (7,982 km2), located in Western Oromia Regional State, Ethiopia was simulated by using soil and water assessment tool (SWAT) model. Assessment of layer staking, mosaicking, image classification and accuracy was carried by ArcGIS. The main target of this study was to determine the SWAT Model applicability and impact of past land-use land-cover change on stream flow of the Anger watershed. The time series data from 1990 to 1999 was used for model parameter calibration, and data from 2000 to 2004 were used to validate the model using the input parameter set. The performance of the SWAT model was evaluated by both R2 time series plots and ENS the statistical measures. The results of the model during calibration for monthly stream flow was R2= 0.90, ENS= 0.76 and during validation R2= 0.84, ENS= 0.63 respectively. Validation of image classification is achieved through Mosaicking image and Google Earth image. The performance of the Arc GIS model was evaluated by using the overall accuracy and kapa coefficient. The agreement between classified land use image and ground truth of the year 1986, 2000 and 2010 were showed a good agreement with result of overall accuracy=88%, 85% and 87% and kapa coefficient=81%, 79% and 82% respectively. Simulation of steam flow of the watershed under the impacts of past land-use land-cover changes can be determined by using SWAT model as a tool for water resources planning and management in this watershed.","PeriodicalId":262934,"journal":{"name":"Journal of Civil, Construction and Environmental Engineering","volume":"10 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114018932","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}

{"title":"Production Process Automation for Construction of Monolithic Buildings and Structures","authors":"V. Vladimir","doi":"10.11648/J.JCCEE.20210603.11","DOIUrl":"https://doi.org/10.11648/J.JCCEE.20210603.11","url":null,"abstract":"Article presents a scientific approach to creating a complex production process automation system for construction of monolithic buildings and structures (MBS). Specific features of systems with complex structure which present themselves in the way they function and by the interaction of local control systems within integrated system for production process automation were discovered. Justification is given to the structure of creation of local systems for automation of MBS construction processes and their functioning within interconnected complex control system. Model for optimal transportation of concrete mixture to the pouring site with sliding thermo-active formwork with hydraulic actuators is presented in the article. The model is integrated by parameters of physical and mechanical processes. Concept of production process automation for construction of MBS was outlined. The concept is implemented in accordance with specific operational and technological and IT support of integrated system for automated control. The greatest potential for increasing the rate of housing construction is possessed by the technology of monolithic housing construction. However, traditional methods of erecting monolithic structures are associated with increased labor intensity, a significant share of manual operations, and the lack of objective instrumental control of the quality of concrete work, which significantly affects the increase in the time and cost of construction. A radical solution to the problem of increasing the efficiency of monolithic housing construction technology is possible only through the integrated use of automation, robotization and microprocessor technology. A method and means have been developed for automating the processes of feeding, distributing, laying and compacting concrete mixture, which make it possible to fundamentally change not only the nature of the work of construction workers, but also its organization, productivity, quality and intellectual saturation. The technical requirements for the automated structures of switchgears are formulated, based on taking into account the specific technological conditions for the production of concrete works. A criterion is proposed and a methodology for choosing the optimal kinematic structure of an automated switchgear for the production of concrete works is developed. The problem of determining the geometric characteristics (the length of the links, the angles of rotation of the joints), the distribution booms for the given constructive and technological conditions of concreting has been solved.","PeriodicalId":262934,"journal":{"name":"Journal of Civil, Construction and Environmental Engineering","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132416231","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}

{"title":"Assessment of Quality Management Practices of Building Construction Firms in Uganda: A Case of Kamwenge District","authors":"M. Lawrence, B. Andrew, Mubiru Joel","doi":"10.11648/J.JCCEE.20210602.17","DOIUrl":"https://doi.org/10.11648/J.JCCEE.20210602.17","url":null,"abstract":"Quality management in the construction industry includes quality control, quality planning and quality assurance to improve the quality of buildings. However, there have been challenges related to cost variations, timeliness and delays in maintenance which affect quality management of buildings. The study assessed quality management practices of building construction firms in Uganda with the purpose of developing a framework that can be used by construction firms to improve on the quality of buildings. In this study, descriptive design was employed in which both qualitative and quantitative data were collected from a sample size of 54 respondents purposively selected from employees of construction firms and Kamwenge local government using a survey questionnaire and documentary reviews. Data were analyzed using descriptive and multivariate analysis in SPSS version 25. The contribution of each of the factors on the quality of construction firms was determined by use of Relative Importance Index (RII) and the ranking of these attributes in terms of their criticality as perceived by the respondents. The findings indicated that procurement systems, third party certification and on site supervision greatly influenced the cost, timeliness and delivery of buildings hence affecting the quality management practices. The developed framework shall be used to engage stakeholders in the phases of the construction projects mainly buildings to improve on cost estimation and timely completion hence improving on quality management of buildings and service delivery.","PeriodicalId":262934,"journal":{"name":"Journal of Civil, Construction and Environmental Engineering","volume":"7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115925895","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}

{"title":"Effect of Different Material Schemes on Carbon Emissions in Construction Material Production Stage","authors":"Yang Hu, Bin Dai, Jianhong Wu, Yinan Wu, Jing Yuan","doi":"10.11648/J.JCCEE.20210602.16","DOIUrl":"https://doi.org/10.11648/J.JCCEE.20210602.16","url":null,"abstract":"Introduction: Building energy consumption accounts for a large proportion of global energy consumption, and it is urgent to reduce building carbon emissions. There are many different components in the Building, each of which produces a somewhat different amount of carbon emissions, such as column, beam, floor, exterior wall and interior wall. This Paper is focusing on looking for the components’ differences in carbon emission in order to provide some valuable advises in choosing building materials. Methods: Using the building information model, the sample building is divided into five parts: column, beam, floor, exterior wall and interior wall. Firstly, the quantities of each part of the building is calculated from building information model. Secondly, the method of permutation and combination is performed by choosing different materials including concrete, steel, wood, brick and glass, and then forming 14 schemes. Finally, carbon emissions at production stages are calculated of all 14 schemes by known carbon emission factors. Conclusion: The average proportion of each part of carbon emissions is obtained both with the carbon emissions from different materials. Choosing the lowest and highest theoretical scheme in order to analysis the influence of different materials on carbon emissions in construction production stage, so that the effective data reference for building energy saving and emission reduction can be concluded.","PeriodicalId":262934,"journal":{"name":"Journal of Civil, Construction and Environmental Engineering","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128159171","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}

{"title":"Analysis on Disease State of Urban Operational Subway Tunnels","authors":"F. Dong, Jun Huang, Ao Li, Caichi Gao","doi":"10.11648/J.JCCEE.20210602.14","DOIUrl":"https://doi.org/10.11648/J.JCCEE.20210602.14","url":null,"abstract":"Structure form, steel bar and service time were considered to be the main factors of the tunnel disease state, based on the disease inspection results of subway tunnels in Beijing. The conclusion indicated that the diseases of shield tunnel such as ovalization of tunnel cross section, lining cracks, crushing and dislocation of duct pieces and water leakage were caused by the deformation of segment joints. Lining crack was the main disease form in monolithic tunnel. The width and depth of cracks were greatly influenced by tunnel operation time and had the characteristics of discreteness and random. Steel bar used in concrete lining could significantly enhance safety of tunnel structures. Water leakage in subway tunnel was influenced by rainfall and usually could be observed at the gaps of tunnel structures, such as bolt holes and segment joint of shield tunnel or the construction joints, deformation joints and lining cracks of monolithic tunnel. The most lining cavities were found located at the vault and the cavity shape was similar to strip, square or oval with lining cracking nearby. The carbonation depth of lining concrete was proportional to tunnel operation time and its value and speed at ballast bed was most, sidewall less and vault least. It is hoped that the results can provide some reference for the disease law analysis and treatment of urban tunnel.","PeriodicalId":262934,"journal":{"name":"Journal of Civil, Construction and Environmental Engineering","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-04-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133219968","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}

{"title":"Strengthening Strategy of Old Bridge in Indonesia (Tukad Yeh Bakung) by Using Optimization and Preservation Approach","authors":"I. N. Sutarja, I. G. M. Susila, Made Ari Ariarsha Sumekar","doi":"10.11648/J.JCCEE.20210602.13","DOIUrl":"https://doi.org/10.11648/J.JCCEE.20210602.13","url":null,"abstract":"A reliable, integrated and sustainable highway road network system throughout the national territory needs to include an upgraded structural capacity of bridges; particularly Tukad Yeh Bakung bridge in Bali-Indonesia. It was essentially needed to improve transportation services to provide direct impacts of economic growth and social welfare locally. To upgrade structural capacity an old bridge has been done by applying a preservation method sustainably: maintenance and rehabilitation in order to keep the bridges provide services properly. This preservation method has also been intended to provide an acceptance and functional criteria (certification of life services) of bridge 50 up to 100 year, and further. An old bridge (Tukad Yeh Bakung) was built in 1977 located along the national road network between Denpasar and Gilimanuk with reference (stationing of km 54+400). The bridge was suffered with structural damages due to exceeded load services, earthquakes, and material degradation. The damages of bent was essentially needed to be preserved since the damages found such as cracked and porous on concrete deck/slab and exposed of slab/bending reinforcement which clearly hazard from corrosions as well as decreasing its capacity. Simple bridge preservation has been done by giving additional or replacement of flexural reinforcement as well as a confinement method for the concrete column. Ultimate capacity ratio (Mu/φMn) of bent has been evaluated and typical confinement method will also increase lateral load capacity of the pier and prevents of collapse (due to local and global/longitudinal buckling).","PeriodicalId":262934,"journal":{"name":"Journal of Civil, Construction and Environmental Engineering","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2021-03-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131350103","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}