Computers and Concrete最新文献_第10页

Shear strength of match-cast-free dry joint in precast girders 预制梁无配浇干缝抗剪强度研究

IF 4.1 4区工程技术

Computers and Concrete Pub Date : 2020-08-01 DOI: 10.12989/CAC.2020.26.2.161

Haibo Jiang, Jiahui Feng, Jie Xiao, Mingzhu Chen, Weibin Liang

{"title":"Shear strength of match-cast-free dry joint in precast girders","authors":"Haibo Jiang, Jiahui Feng, Jie Xiao, Mingzhu Chen, Weibin Liang","doi":"10.12989/CAC.2020.26.2.161","DOIUrl":"https://doi.org/10.12989/CAC.2020.26.2.161","url":null,"abstract":"Shear keys in precast concrete segmental bridges (PCSBs) are usually match-casting which is very labour intensive. In this research, an innovative match-casting-free construction was proposed by leaving small gap between the convex and the concave castellated shear keys in the joints of PCSBs. Specimen experiment, shear strength analysis and numerical simulation were conducted, investigating the loading performance of this new type of dry joints, the gap dry joints. Compared with matchcasting joint specimens, it has been found from experiment that shear capacity of gap joint specimens significantly decreased ranging from 17.75% to 42.43% due to only partially constrained and contacted in case of gap dry joints. Through numerical simulation, the effects of bottom contacting location, the heights of the gap and the shear key base were analyzed to investigate strength reduction and methods to enhance shear capacity of gap joint specimens. Numerical results proved that shear capacity of gap dry joints under full contact condition was higher than that under partial contact. In addition, left contact destroyed the integrity of shear keys, resulting in significant strength reduction. Larger shear key base remarkably increased shear capacity of the gap joint. Experimental tests indicated that AASHTO provision underestimated shear capacity of the match-casting dry joint specimens, while the numerical results for the gap dry joint showed that AASHTO provision underestimated shear capacity of full contact specimens, but overestimated that of left contact specimens.","PeriodicalId":50625,"journal":{"name":"Computers and Concrete","volume":"204 1","pages":"161"},"PeriodicalIF":4.1,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72772843","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}

引用次数: 5

A generalized 4-unknown refined theory for bending and free vibration analysis of laminated composite and sandwich plates and shells 层合复合材料和夹层板壳弯曲和自由振动分析的广义4未知精化理论

IF 4.1 4区工程技术

Computers and Concrete Pub Date : 2020-08-01 DOI: 10.12989/CAC.2020.26.2.185

O. Allam, K. Draiche, A. A. Bousahla, F. Bourada, A. Tounsi, K. H. Benrahou, S. R. Mahmoud, E. A. Bedia, A. Tounsi

{"title":"A generalized 4-unknown refined theory for bending and free vibration analysis of laminated composite and sandwich plates and shells","authors":"O. Allam, K. Draiche, A. A. Bousahla, F. Bourada, A. Tounsi, K. H. Benrahou, S. R. Mahmoud, E. A. Bedia, A. Tounsi","doi":"10.12989/CAC.2020.26.2.185","DOIUrl":"https://doi.org/10.12989/CAC.2020.26.2.185","url":null,"abstract":"This research is devoted to investigate the bending and free vibration behaviour of laminated composite/sandwich \u0000plates and shells, by applying an analytical model based on a generalized and simple refined higher-order shear deformation theory (RHSDT) with four independent unknown variables. The kinematics of the proposed theoretical model is defined by an undetermined integral component and uses the hyperbolic shape function to include the effects of the transverse shear stresses through the plate/shell thickness; hence a shear correction factor is not required. The governing differential equations and associated boundary conditions are derived by employing the principle of virtual work and solved via Navier-type analytical \u0000procedure. To verify the validity and applicability of the present refined theory, some numerical results related to displacements, stresses and fundamental frequencies of simply supported laminated composite/sandwich plates and shells are presented and compared with those obtained by other shear deformation models considered in this paper. From the analysis, it can be concluded that the kinematics based on the undetermined integral component is very efficient, and its use leads to reach higher accuracy than conventional models in the study of laminated plates and shells.","PeriodicalId":50625,"journal":{"name":"Computers and Concrete","volume":"92 1","pages":"185"},"PeriodicalIF":4.1,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"90506574","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}

引用次数: 91

On static bending of multilayered carbon nanotube-reinforced composite plates 多层碳纳米管增强复合材料板的静态弯曲研究

IF 4.1 4区工程技术

Computers and Concrete Pub Date : 2020-08-01 DOI: 10.12989/CAC.2020.26.2.137

A. Daikh, Ismail Bensaid, Attia Bachiri, M. Houari, A. Tounsi, T. Merzouki

引用次数: 7

A model to characterize the effect of particle size of fly ash on the mechanical properties of concrete by the grey multiple linear regression 建立了粉煤灰粒径对混凝土力学性能影响的灰色多元线性回归模型

IF 4.1 4区工程技术

Computers and Concrete Pub Date : 2020-08-01 DOI: 10.12989/CAC.2020.26.2.175

Yunpeng Cui, Jun Liu, Licheng Wang, Run-qing Liu, B. Pang

{"title":"A model to characterize the effect of particle size of fly ash on the mechanical properties of concrete by the grey multiple linear regression","authors":"Yunpeng Cui, Jun Liu, Licheng Wang, Run-qing Liu, B. Pang","doi":"10.12989/CAC.2020.26.2.175","DOIUrl":"https://doi.org/10.12989/CAC.2020.26.2.175","url":null,"abstract":"Fly ash has become an important component of concrete as supplementary cementitious material with the development of concrete technology. To make use of fly ash efficiently, four types of fly ash with particle size distributions that are in conformity with four functions, namely, S.Tsivilis, Andersen, Normal and F distribution, respectively, were prepared. The four particle size distributions as functions of the strength and pore structure of concrete were thereafter constructed and investigated. The results showed that the compressive and flexural strength of concrete with the fly ash that conforming to S.Tsivilis, Normal, F distribution increased by 5-10 MPa and 1-2 MPa, respectively, compared to the reference sample at 28 d. The pore structure of the concrete was improved, in which the total porosity of concrete decreased by 2-5% at 28 d. With regarding to the fly ash with Andersen distribution, it was however not conducive to the strength development of concrete. Regression model based on the grey multiple linear regression theory was proved to be efficient to predict the strength of concrete, according to the characteristic parameters of particle size and pore structure of the fly ash.","PeriodicalId":50625,"journal":{"name":"Computers and Concrete","volume":"11 1","pages":"175"},"PeriodicalIF":4.1,"publicationDate":"2020-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80342553","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}

引用次数: 4

Free vibration of sandwich micro-beam with porous foam core,GPL layers and piezo-magneto-electric facesheets via NSGT 多孔泡沫芯、GPL层和压电磁电面板夹层微梁的NSGT自由振动

IF 4.1 4区工程技术

Computers and Concrete Pub Date : 2020-07-01 DOI: 10.12989/CAC.2020.26.1.075

M. Mohammadimehr, S. Firouzeh, Mahsa Pahlavanzadeh, Yaser Heidari, M. Irani-Rahaghi

{"title":"Free vibration of sandwich micro-beam with porous foam core,GPL layers and piezo-magneto-electric facesheets via NSGT","authors":"M. Mohammadimehr, S. Firouzeh, Mahsa Pahlavanzadeh, Yaser Heidari, M. Irani-Rahaghi","doi":"10.12989/CAC.2020.26.1.075","DOIUrl":"https://doi.org/10.12989/CAC.2020.26.1.075","url":null,"abstract":"The aim of this research is to investigate free vibration of a novel five layer Timoshenko microbeam which consists of a transversely flexible porous core made of Al-foam, two graphen platelets (GPL) nanocomposite reinforced layers to enhance the mechanical behavior of the structure as well as two piezo-magneto-electric face sheets layers. This microbeam is subjected to a thermal load and resting on Pasternak's foundation. To accomplish the analysis, constitutive equations of each layer are derived by means of nonlocal strain gradient theory (NSGT) to capture size dependent effects. Then, the Hamilton's principle is employed to obtain the equations of motion for five layer Timoshenko microbeam. They are subsequently solved analytically by applying Navier's method so that discretized governing equations are determined in form of dynamic matrix giving the possibility to gain the natural frequencies of the Timoshenko microbeam. Eventually, after a validation study, the numerical results are presented to study and discuss the influences of various parameters such as nonlocal parameter, strain gradient parameter, aspect ratio, porosity, various volume fraction and distributions of graphene platelets, temperature change and elastic foundation coefficients on natural frequencies of the sandwich microbeam.","PeriodicalId":50625,"journal":{"name":"Computers and Concrete","volume":"109 1","pages":"75"},"PeriodicalIF":4.1,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"79589393","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}

引用次数: 3

Research on damage of 3D random aggregate concrete modelunder ultrasonic dynamic loading 超声动荷载作用下三维随机骨料混凝土模型损伤研究

IF 4.1 4区工程技术

Computers and Concrete Pub Date : 2020-07-01 DOI: 10.12989/CAC.2020.26.1.011

Lixiao Wang, Qidong Chen, Xin Liu, Bin-bin Zhang, Shen Yichen

引用次数: 0

Minimum cost design of RCMRFs based on consistent approximation method 基于一致逼近法的rcmrf最小成本设计

IF 4.1 4区工程技术

Computers and Concrete Pub Date : 2020-07-01 DOI: 10.12989/CAC.2020.26.1.001

A. Habibi, Mobin Shahryari, H. Rostami

引用次数: 0

Vibration analysis of porous nanocomposite viscoelastic plate reinforced by FG-SWCNTs based on a nonlocal strain gradient theory 基于非局部应变梯度理论的FG-SWCNTs增强多孔纳米复合粘弹性板振动分析

IF 4.1 4区工程技术

Computers and Concrete Pub Date : 2020-07-01 DOI: 10.12989/CAC.2020.26.1.031

P. Khazaei, M. Mohammadimehr

{"title":"Vibration analysis of porous nanocomposite viscoelastic plate reinforced by FG-SWCNTs based on a nonlocal strain gradient theory","authors":"P. Khazaei, M. Mohammadimehr","doi":"10.12989/CAC.2020.26.1.031","DOIUrl":"https://doi.org/10.12989/CAC.2020.26.1.031","url":null,"abstract":"This paper investigates the size dependent effect on the vibration analysis of a porous nanocomposite viscoelastic plate reinforced by functionally graded-single walled carbon nanotubes (FG-SWCNTs) by considering nonlocal strain gradient theory. Therefore, using energy method and Hamilton's principle, the equations of motion are derived. In this article, the effects of nonlocal parameter, aspect ratio, strain gradient parameter, volume fraction of carbon nanotubes (CNTs), damping coefficient, porosity coefficient, and temperature change on the natural frequency are perused. The innovation of this paper is to compare the effectiveness of each mentioned parameters individually on the free vibrations of this plate and to represent the appropriate value for each parameter to achieve an ideal nanocomposite plate that minimizes vibration. The results are verified with those referenced in the paper. The results illustrate that the effect of damping coefficient on the increase of natural frequency is significantly higher than the other parameters effect, and the effects of the strain gradient parameter and nonlocal parameter on the natural frequency increase are less than damping coefficient effect, respectively. Furthermore, the results indicate that the natural frequency decreases with a rise in the nonlocal parameter, aspect ratio and temperature change. Also, the natural frequency increases with a rise in the strain gradient parameter and CNTs volume fraction. This study can be used for optimizing the industrial and medical designs, such as automotive industry, aerospace engineering and water purification system, by considering ideal properties for the nanocomposite plate.","PeriodicalId":50625,"journal":{"name":"Computers and Concrete","volume":"21 1","pages":"031"},"PeriodicalIF":4.1,"publicationDate":"2020-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78252955","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}

引用次数: 2

Prediction of the critical buckling load of SWCNT reinforcedconcrete cylindrical shell embedded in an elastic foundation 弹性地基中swcnts钢筋混凝土圆柱壳的临界屈曲荷载预测

IF 4.1 4区工程技术

Computers and Concrete Pub Date : 2020-07-01 DOI: 10.12989/CAC.2020.26.1.053

A. Timesli

引用次数: 12

Bending analysis of functionally graded porous platesvia a refined shear deformation theory 基于精细剪切变形理论的功能梯度多孔板弯曲分析

IF 4.1 4区工程技术

Computers and Concrete Pub Date : 2020-07-01 DOI: 10.12989/CAC.2020.26.1.063

A. Zine, A. A. Bousahla, F. Bourada, K. H. Benrahou, A. Tounsi, E. A. Bedia, S. R. Mahmoud, A. Tounsi

引用次数: 98