Electronic Journal of Structural Engineering最新文献_第8页

Evaluation the Effect of Carbon Nanotube on the Rheological and Mechanical Properties of Bitumen and Hot Mix Asphalt (HMA) 碳纳米管对沥青和热拌沥青（HMA）流变和力学性能影响的评价

IF 0.6

Electronic Journal of Structural Engineering Pub Date : 2017-01-01 DOI: 10.56748/ejse.17221

M. Zahedi, M Barati, M. Zarei

{"title":"Evaluation the Effect of Carbon Nanotube on the Rheological and Mechanical Properties of Bitumen and Hot Mix Asphalt (HMA)","authors":"M. Zahedi, M Barati, M. Zarei","doi":"10.56748/ejse.17221","DOIUrl":"https://doi.org/10.56748/ejse.17221","url":null,"abstract":"The technical characteristics of modified bitumen and asphalt have provided many study opportunities around the world. This article has assessed the effects of adding the Nanomaterial on the rheological specifications of bitumen by adding carbon nanotubes to bitumen and it also has evaluated the physical characteristics and bulk parameters of the surface (Topeka) layer of asphalt concrete sample by conducting Marshall Tests. In this regard, the technical characteristics of bitumen such as penetration grade, softening point, viscosity and thermal sensitivity were tested by adding carbon nanotubes with the amounts of 0.25, 0.50, 1 and 1.5 percent by weight of bitumen. The results show that adding carbon nanotube to the bitumen has been accompanied with a reduction in the penetration grade and an increase in softness of the bitumen, which improves the specifications of bitumen and therefore reduces asphalt tracking at high temperature. Following, the asphalt samples reinforced with carbon nanotubes evaluated for conducting Marshall Test. The results showed that the additive alters the Marshall Test parameters such as increasing the strength and decreasing the flow. Meanwhile, the specific gravity of asphalt mixture was increased and the void space percent of the aggregates was relatively decreased. Moreover, the void space of the asphalt mixture and the void space percent filled with bitumen were relatively increased. Economic analysis was evaluated for a 3-way path. Finally, according to the results and analysis of the Nanomaterial on the Nano specifications of bitumen and asphalt, technically, the results strongly suggest the use of carbon nanotubes. Although economically, the use of carbon nanotubes is limited.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49421016","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}

引用次数: 25

Minimum Longitudinal Reinforcement Requirements for Boundary Elements of Limited Ductile Walls for AS 3600 AS 3600有限延性墙边界构件的最低纵向钢筋要求

IF 0.6

Electronic Journal of Structural Engineering Pub Date : 2017-01-01 DOI: 10.56748/ejse.17218

R.D. Hoult

{"title":"Minimum Longitudinal Reinforcement Requirements for Boundary Elements of Limited Ductile Walls for AS 3600","authors":"R.D. Hoult","doi":"10.56748/ejse.17218","DOIUrl":"https://doi.org/10.56748/ejse.17218","url":null,"abstract":"Observations of poor performance of reinforced concrete walls in recent earthquake events have been associated with a light amount of longitudinal reinforcement. In particular, single-crack failures have been observed for reinforced concrete walls that have an insufficient amount of longitudinal reinforcement to allow secondary cracking. It has been proposed that the next revision of the Concrete Structures code in Australia (AS 3600) increase the current minimum longitudinal reinforcement required for limited ductile reinforced concrete walls to mitigate against this type of failure in the event of a large earthquake. This research investigates the current and proposed longitudinal reinforcement requirements of AS 3600. A reinforced concrete wall is analysed using a state-of-the-art finite element modelling program for a range of different longitudinal reinforcement configurations. The wall detailed to the minimum longitudinal reinforcement requirements proposed for the next revision of AS 3600, which requires boundary elements, was found to allow secondary cracking and using less bars than a wall with distributed reinforcement. The displacement capacities of the walls that formed secondary cracks are found to be limited unless transverse reinforcement is used to confine the longitudinal reinforcement in the boundary ends of the wall.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"44933575","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}

引用次数: 2

Experimental Study on the Effect of Resin Anchoring Agent Mixing with Steel Grit 树脂锚固剂与钢渣混合效果的试验研究

IF 0.6

Electronic Journal of Structural Engineering Pub Date : 2017-01-01 DOI: 10.56748/ejse.17216

J Han, W.J. Xie, M. Zhang, H.D. Zhang, C. Cao

引用次数: 0

Investigating Amorphous Composition Mix Design Performance and Properties of Fly Ash-Based Geopolymer 粉煤灰基地聚合物非晶态组合料设计、性能及性能研究

IF 0.6

Electronic Journal of Structural Engineering Pub Date : 2017-01-01 DOI: 10.56748/ejse.17217

J. Sweeney, T. Htut, W.Y. Huen, V. Vimonsatit, T.S. Ng

{"title":"Investigating Amorphous Composition Mix Design Performance and Properties of Fly Ash-Based Geopolymer","authors":"J. Sweeney, T. Htut, W.Y. Huen, V. Vimonsatit, T.S. Ng","doi":"10.56748/ejse.17217","DOIUrl":"https://doi.org/10.56748/ejse.17217","url":null,"abstract":"Identifying viable replacement for Ordinary Portland Cement (OPC) is part of the effort to limit CO2 emission during its production. Fly ash-based geopolymer composites have emerged as a sustainable and promising replacement product with proven comparable binding properties, coupled with superior characteristic in some area, when compared to OPC. However, fly ash being a by-product of coal combustion, remains unfavourable in industry application due to its deferring composition dependent on the type of coal feedstock, resulted in inconsistent mechanical and chemical properties produced. In order to overcome this shortcoming, a unified method to evaluate fly ash at the amorphous composition level is required. This study aims to tackle this challenge by establishing a framework to effectively identify relationship among the fly ash amorphous content and identifying an optimum proportion of alkaline activator in order to optimise its full potential in geopolymer concrete or mortar production. This is achieved by utilising XRF and Q-XRD analyses on geopolymer specimen’s amorphous compositions and evaluate their respective compressive strength through laboratory testing. A number of testing variants are carried out including curing regime, alkaline activator concentrations, presence of mechanical activation and deferring water content are investigated.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43272158","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}

引用次数: 2

Strain Rates in Prestressed Concrete Sleepers and Effects on Cracking Loads 预应力混凝土枕木的应变率及其对开裂荷载的影响

IF 0.6

Electronic Journal of Structural Engineering Pub Date : 2017-01-01 DOI: 10.56748/ejse.17220

J. Taherinezhad, M. Sofi, P. Mendis, T. Ngo

{"title":"Strain Rates in Prestressed Concrete Sleepers and Effects on Cracking Loads","authors":"J. Taherinezhad, M. Sofi, P. Mendis, T. Ngo","doi":"10.56748/ejse.17220","DOIUrl":"https://doi.org/10.56748/ejse.17220","url":null,"abstract":"Prestressed concrete sleepers (PCSs) play an essential role in structural response and performance of ballasted railway tracks. Due to defects in track or train components, high magnitude dynamic loads may generate at the rail head and transfer to the PCSs which can generate cracks in PCSs. Cracking from dynamic loads have been reported as the most critical problem of PCSs around the world and impose an early replacement of sleepers which is a financial burden to the rail industry. This paper investigates the effects of strain rates on the strength enhancement of PCS. By using available measurements, the strain rates are calculated at two critical points of the PCSs, the rail seat and midspan. Considering the dynamic increase factor (DIF) of concrete, the cracking loads of a PCS are calculated and are compared with commonly occurring dynamic loads. Results show that the maximum strain rates at both rail seat and midspan are about 0.08 and 0.016 1/s, respectively. The increase of cracking wheel load due to the strain rate effects is about 5 to 26 percent. The results are also shown to be able to demonstrate the level cracking from dynamic loads with very short return periods.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":" ","pages":""},"PeriodicalIF":0.6,"publicationDate":"2017-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42887227","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}

引用次数: 3

Residual Strength of Blended Cement Pastes and Mortar Exposed to Elevated Temperatures 高温下混合水泥膏体和砂浆的残余强度

IF 0.6

Electronic Journal of Structural Engineering Pub Date : 2016-01-01 DOI: 10.56748/ejse.16208

Hyuk Lee, Vanissorn Vimonsatit, Prinya Chindaprasirt

{"title":"Residual Strength of Blended Cement Pastes and Mortar Exposed to Elevated Temperatures","authors":"Hyuk Lee, Vanissorn Vimonsatit, Prinya Chindaprasirt","doi":"10.56748/ejse.16208","DOIUrl":"https://doi.org/10.56748/ejse.16208","url":null,"abstract":"This paper presents the outcome of a series of tests to determine properties of blended cement pastes and mortar mixtures using Taguchi’s design of experiment approach. Fly ash (FA), water to cementitious material ratio (w/c), superplasticiser (SP) and sand to cementitious material ratio (s/c) are the main parameters considered. Mixture samples were tested at varying temperatures up to 800oC. The ANOVA results and regression analysis show that an increase in FA content and w/c ratio lead to a decrease in the density of blended cement. For compressive strength development, an increase in FA content and s/c ratio decreased the compressive strength development. Within the tested levels of the parameters, the optimum mix to achieve the highest compressive strength of blended cement mixtures is 20% of FA content, 1.5 of s/c ratio, 0.35 of w/c ratio and 0.2% of SP. Increasing the content of FA and SP improved the overall residual strength, and the optimum mix design to achieve the highest residual strength is 20% of FA, 1.5 of s/c ratio, 0.35 of w/c ratio and 0.2 of SP. Based on all the test results, an empirical formula for predicting residual strength of blended cement paste and mortar is proposed.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2016-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70725986","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}

引用次数: 0

Heavy concrete on cement with slag of low-carbon ferrochrome 低碳铬铁渣水泥的重质混凝土

IF 0.6

Electronic Journal of Structural Engineering Pub Date : 2016-01-01 DOI: 10.56748/ejse.16205

Zyryanov, F. A., A. B. Bukreev, O. O. Zyryanova

引用次数: 1

Prestress Loss Distributions along Simply Supported Pretensioned Concrete Beams 简支预应力混凝土梁的预应力损失分布

IF 0.6

Electronic Journal of Structural Engineering Pub Date : 2016-01-01 DOI: 10.56748/ejse.16207

J. Kent Hsiao

引用次数: 0

A Comprehensive Review of Spalling and Fire Performance of Concrete Members 混凝土构件的剥落和防火性能综述

IF 0.6

Electronic Journal of Structural Engineering Pub Date : 2015-06-01 DOI: 10.56748/ejse.15199

M. Hedayati, M. Sofi, P. Mendis, T. Ngo

引用次数: 19

Study on the Seismic Response Parameters of Steel Medium-Height Buildings with Framed-Tube Skeleton under Near-Fault Records 近断层记录下框架-筒骨架钢结构中高层建筑地震反应参数研究

IF 0.6

Electronic Journal of Structural Engineering Pub Date : 2015-06-01 DOI: 10.56748/ejse.15204

M. Azhdarifar, A. Meshkat-Dini, A. Sarvghad-Moghadam

{"title":"Study on the Seismic Response Parameters of Steel Medium-Height Buildings with Framed-Tube Skeleton under Near-Fault Records","authors":"M. Azhdarifar, A. Meshkat-Dini, A. Sarvghad-Moghadam","doi":"10.56748/ejse.15204","DOIUrl":"https://doi.org/10.56748/ejse.15204","url":null,"abstract":"In this research, the performance abilities of tube type lateral load resistant framed systems are studied in order to assess the dynamic response properties of mid-rise steel structures under effects of far and near-field ground motions. For this purpose, three 10 story structural models with separated framed tube based skeletons were selected and designed. The structural models have been designed according to the Iranian seismic code 2800 (4th edition). The main criterion which was considered to select powerful ground motions for performing nonlinear time history analyses is the existence of energized coherent velocity pulses as well as high amplitude acceleration spikes in the time history of each earthquake record. Assessment of the analytical results should emphasize the importance of both lateral displacement and drift parameters which must be taken into account during the structural design phase. Furthermore, it was concluded that the maximum drift demand is more than 0.035 and the upper level of rotation of rigid connecting zones was obtained more than 5 percentages of a radian. As a general note, it was concluded that the seismic response parameters of mid-rise steel framed tube structures are intensively influenced by those strong earthquake records which contain powerful forward directivity effects and are able to emerge long period pulses in their time histories.","PeriodicalId":52513,"journal":{"name":"Electronic Journal of Structural Engineering","volume":"1 1","pages":""},"PeriodicalIF":0.6,"publicationDate":"2015-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"70726130","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}

引用次数: 0