共查询到20条相似文献，搜索用时 812 毫秒
1.
In the elastic-plastic solution of expansion of cylinder cavities based on Tresca strength criterion and Mohr-Coulomb strength criterion, the influence of neutral principal stress is not considered. In this paper the influence of neutral principal stress on elastic-plastic solution of expansion of cylinder cavities is considered. The calculation shows that the radius and displacement of plastic zone will reduce when the neutral principal stress is considered. The conclusions are of practical significance for geotechnical engineering. 相似文献
2.
In this paper, the total input earthquake energy and influencing effects for shear type,shear-bending type, bending type aseismic structures of the single freedom system and multiple freedom elastic-plastic system are analyzed by synthesizing various effects and employing the timehistory analysis method. Based on the analysis results, the total input earthquake energy spectrum is presented.The simplified methods for analyzing the total input energy of multiple freedom elastic-plastic systems are proposed to provide some basis for developing aseismic structure design method and Double-Failure Criteria. 相似文献
3.
Deformation measurement and analysis play an important role in geotechnical model tests. Using the concept of quadrilateral isoperimetric element, the strain filed was achieved from the calculation method based on displacement modes, and the verification results show that this measurement technique has a reliable precision. The soil deformation in model test of square shallow foundation was measured by using this technique, and the results show that the measurement system based on digital image correlation method can realize the whole process quantitative measurement of soil displacement field and shear strain filed. This deformation measurement technique provides a tool for the qualitative and quantitative analysis of soil micromechanics characteristics. 相似文献
4.
This paper introduces the analysis and test of prestressed flat beams in tube-in-tube concrete structures at different construction stages; moreover, the corresponding structural analysis models with FEA program are set up. Through the comparative analysis between the results of construction field test and that of calculation with FEA method, it proves the reliability of the primary design method; meanwhile, it also indicates that establishment of prestressing force and prestressed effects in similar structures is a complex procedure and should be noticed. 相似文献
5.
GUO Chao ZHANG Yong-xing LUO Jun-cai ZHOU Zhi-ming ZHANG bo-hu LI Jin-long XIE Wen-ting WU De-jun 《保鲜与加工》2011,(4):106-112
By using near crack line analysis method and Mohr-Coulomb strength criterion,the elastic-plastic solution for near crack line of an eccentric cracks loaded by the pore water pressure under large scale yielding condition is analyzed.The elastic stress fields,the plastic stress field,the unit normal vector of the elastic-plastic boundary near the crack line,the elastic-plastic stress fields near crack line are identified.The change pattern of the length of the plastic zone and the pore water pressure is presented.Besides,the elastic-plastic analytical solution for an eccentric cracks loaded by the pore water pressure is obtained. 相似文献
6.
This paper introduced basic concept and resolvent of nonlinear FEA, the analysis of intensity and stiffness of the rear leaf spring on SC1020 vehicle was carried out with contact nonlinear function of FEA program ANSYS, and the pre-stress distribution and pre-deformation after assembled were introduced , the stress distribution and deformation under different loads had also been presented. Thus we can calculate the mechanical and dynamic performance of leaf spring at the design stage. The result showed a great agreement with the test. It is convinced that the CAE (Computer Aided Engineering) technology can improve the design of vehicle suspension and the cost and time can be saved. 相似文献
7.
Wang Cheng Zhang Jianhui Deng Anfu 《保鲜与加工》1998,(4):58-63
In this paper the problem of collinear multi-joint in rockmass loaded by shearing-compressive stresses is simplified as that of a joint in finite rockmass. The basic equations with Mohr-Coulomb criterion are solved by the line field analysis method near the joint line in an elastic-perfectly plastic materials. Through a reasonable boundary condition on the joint surface and matching conditions at the elastic-plastic boundary, the relation between length of the plastic region on the joint line and the shearing-compressive stresses is obtained. The failure laws of the rockmass contained collinear joints are also obtained. 相似文献
8.
In process of the tunnel construction throw New Austrian Tunnelling Method, the result of smoothwall blasting to rock tunnel is not good, there are more and more cavities produced behind the lining. On the basis of engineering project, this paper makes the three-dimensional elastic-plastic analysis throw numerical simulation, discusses the stress-strain behavior of primary support when there is a different size of rectangle cavity behind the lining. In addition the safety factor of tunnel is calculated with cavity based on the strength reduction finit element method. This factor is compared with the factor of health tunnel. The stability of tunnel structure system is estimated through the linear regression analysis between stress of lining and safety factor. 相似文献
9.
In this paper, the elastic-plastic transitional interface in an elastic body under impacting has been analyzed by means of a new experiment method, a satisfied strain field is obtained, hence a reliable basis for the calculating of dynamic yielding stresses is provided. 相似文献
10.
ZHOU Xiao-ping~ 《保鲜与加工》2004,(1):73-76
In elastic-plastic solution of expansion of spherical cavities, based on Mohr-Coulomb strength criterion, the effect of intermediate principal stress on yield and failure of soil is not analyzed. Therefore, there is disparity between results obtained by Mohr-Coulomb strength criterion and those obtained from experimental data. In this paper, the elastic-plastic solution of expansion of spherical cavities, based on unified strength theory is established and unified solutions are obtained. The corresponding solutions of different materials can be obtained. The unified solution cannot only be used to fit the properties of the materials with different tension-pressure strength, but also those with equal tension-pressure strength. The results show that by this solution, full use of the properties of the materials can be attained to reduce supports, which is of important significance for engineering 相似文献
11.
This paper calculated the maximum elastic displacment respose based on the elastic acceleration spectrum in the current Seismic Design Code, and find the vary relations of the ratio of the elastic-plastic displacement to elastic displacement with the nature peorid of the SDOM systmes. The simplified formulas to calculate the elastic-plastic displacement are given based on the elastic acceleration specturem in the current Seismic Design Code by regression method. 相似文献
12.
Dendriform connections of concrete filled steel rectangular tubes (CFSRT) are composed of a bifurcated column and double cruciform beam column connections. A 3 D nonlinear finite element analysis (FEA) which considers all nonlinear effects of materials, geometry and contact interfaces is established. Analysis of the FEA results show that the load displacement curves at the ends of the beam and hysteretic curves obtained experimentally and via FEA agreed with each other. The stiffener transfers the tension compression stress efficiently, the middle hole has little influence on the stress transfer, and the compressive zone of the core concrete under repeated loading has a greater contribution to the compression stress transfer. 相似文献
13.
XIAO Ming_kui YAN Tao WANG Yao_wei LAI Ming 《保鲜与加工》1999,(5):117-121
The research on seismic response spectra of Elastic-Plastic structures has gained a lot of useful results with the development of the research on seismic response of elastic-plastic structures.This paper discusses the various kinds of elastic-plastic response spectra and points out the key problem which must be solved for their use in seismic design. 相似文献
14.
To investigate the work condition of the aircraft actuators in high temperatureheat transfer process of the output unit of a cycloidal reducer of the actuator is taken into account by Unigraphics NXHypermesh and ANSYS softwares based on finite element analysis(FEA).The temperature distribution of the output unit is obtained by meshing modelapplying loads and solving discrete problems.Thenthe temperature variation of the output unit is gotten by sampling and processing the data of FEA results.In the endthree main conclusions are drawn.Firstthe heat transfer process of the output units of cycloidal reducers of actuators can be analyzed by FEA efficiently.Secondthe temperature of the rudder and the design position of cycloid gears are two major factors in the operating life of reducers.Thirdthe operating life can be improved by lowering the rudder temperature and installing the cycloidal gear as far as possible away from the heat source. 相似文献
15.
It provides several typical mega plane frame designs on condition that the variables are the combination of varying amplification factors of moment at bottom sections of ground floor columns of the minor frame on the major beams. The elastic-plastic dynamic analysis program Drain-2d+ of the plane structure is used to get elastic-plastic time-history analysis for each typical mega frame under the action of seism. The autuors obtain the information of the mechanical transmutation characteristics, the emergency of the plastic hinge and the weak point of the whole structure under the action of seism, from which the correct thinking of how to obtain the design value of amplification factors of moments at bottom sections of ground floor columns of the minor frame on the major beams is found. The reasonable design values are recommended in order to provide some suggestions for the design of the reinforced concrete mega-frame structure. 相似文献
16.
17.
Based on a project of pipe truss roof framing in Chengdu, the ultimate limit state analysis is performed on cast steel joints by using FEM, in which Linear hardening elastic-plastic constitutive model is considered. The results show that, the joint has a great accumulation of plastic strain in ultimate loads, and the point of maximum stress is different from that in elastic with the development of the yielding zone. The paper propoes to use rate-type tensor for the large strain geometric nonlinear problem, shows the criterion of failure formation , and indicates that its essential to apply limit state analysis to the determination of the weakest location on cast steel joint design, which provides basis for understanding the failure modes and failure mechanism of cast steel joint and the cast steel joint design. 相似文献
18.
This paper presents a simplified plastic zone method with consideration of the in-fluences of the PDelta. residual stress ,degradation of crosssectional stiffness and plastic zone lengthon the stiffness matrix for second-order elastic-plastic analysis of steel frames. The method not onlymakes up for a insufficiency which is that the degradation of crosssectional stiffness and plasticzone length in a member ean not be considered by a plastic hinge method but also overcomes a defectwhich is very costly and time-consuming because a fine mesh discretization across the crosssectionand along the member length is required by a plastic zone methed. Analysis result Shows proposedsimplified rnethod is simple and practical. 相似文献
19.
Zhou Shizhen 《保鲜与加工》1996,(2):61-76
In this paper, ultimate loading capacity of eccentric compressed timber column and elastic-plastic behaviour of the material of the cross section are considered.An approximate theoretic method dealing with the maximum mid-span deflection of the column when breaking is advanced.As a result, a formula calculating failure deflection of the rectangular cross section is derived. The results of theoretic calculation are well coincident with those of tests. 相似文献
20.
Performance-based seismic design involves how to confirm inelastic displacement demand of structures under earthquake in concise and reasonable way. Two shortages need to improve in analyzing the elastic-plastic seismic responses of structures if the traditional capacity methods are employed. The shortages are the uncertainty of equivalent high damp of elastic-plastic structures and the limitation of the higher order vibration mode effect being not taken into account. To solve these problems, the authors propose the concept and analyzing process of improved capacity spectrum method based on modal pushover analysis and the elastic seismic responses spectrum modified by strength reduction coefficient and ductile coefficient. The example of analyzing the performance of frame structure is shown which may be a simple and effective method used in engineering. This method has application potential in Performance-based seismic design. 相似文献