Papers by Keyword: Deformation

Abstract: To research the deformation regularity of large section loess tunnel in construction procession with different construction methods, 3D Numerical Simulation is applied and the large-section loess tunnel of highway is taken as an example. Comparing deformation regularity of surrounding rock in three types of construction method conditions, the research results show that:The CRD method takes precedence in the condition of the convergence of surrounding rock is large. The both sides heading method takes precedence in the condition of ground surface settlement is large.

Abstract: The method of MMCP (modified modal cyclic pushover) which can reflect the dual criterion of deformation and energy was used to make an assessment on seismic performances of the steel reinforced concrete piers and reinforced concrete bridge piers. Then the calculated results were analyzed comparing with the results of dynamic time historical analysis and quasi static test. To some extent, the MMCP analysis may simulate the seismic action. In addition, the MMCP method can also be associated with the design response spectrum, making the evaluation results to be reliable and safe. The results indicate that MMCP applicability analysis also exists in the steel reinforced concrete structure, and the seismic capacity of steel reinforced concrete bridge piers is better than reinforced concrete bridge piers.

Abstract: The deformation and support technology of soft roadway is a very important problem in mine. Based on the roadway’s deformation of Jian Xin Mine of Jiangxi Fengcheng Mining Bureau, the mechanics mechanism and reasons of the soft rock roadway deformation are analyzed. And the three kinds of support technologies which are suitable for soft rock roadway are put forward. The support technologies have been used in the soft rock roadway of coal mine and have achieved good results. The research has important reference value for soft rock roadway supporting technology and its stability maintenance.

Abstract: Several laboratory model tests were carried out on the bearing capacity of strip footings on reinforced soil foundation and reinforced slope. Compared with unreinforced cases, the deformation and failure of reinforced earth in different foundation conditions were monitored and analyzed. In order to visualize a failure mechanism when the ground reaches the state of limit equilibrium, a new numerical procedure was proposed. Assuming an elastic-perfectly plastic model, a smeared shear band approach and a modified initial stress method enable the proposed procedure to create an explicit collapse mode by the stress yield condition. On the basis of the development of failure mode and deformation of foundation, the bearing capacity of strip footings can be significantly increased by the inclusion of geotextile. And because the procedure considers the stiffness and deformation of the material, it may be applied to complex stability problems.

Abstract: There are many uncertainty factors which can influence the carrier pile design and construction, some of them can lead the deformation characteristic of carrier pile more complex, especially the carrier pile shape parameter. Based on the on-site testing results and the finite element simulation conclusion, the paper studied the effects of shape parameter on deformation characteristics of the carrier pile from the aspect of bottom head size, pile diameter size, gravel soil zone size, etc. The research found that increase the size of the bottom head and the size gravel soil zone can reduce the amount of deformation to a certain extent; the effect of pile diameter size increase on reducing the deformation is not obvious.

Abstract: Gui Dan intercity cable-stayed bridge adopted the cantilever construction technique, and controlled construction work to ensure that the internal force and linear be similar to the design value. Linear control was mainly carried out by construction position elevation monitoring. Therefore, the construction control point elevation and the axis measure should be strengthened, and the results of each measure stage should be analyzed and compared with the results of monitoring model calculation to modify calculation model, and get a precise simulation model for the construction state. Calculating on account of the bridge state and adjusting the formwork elevation made the bridge linear approach to the design value, to ensure the project quality, safety and duration meet the contract requirement.

Abstract: A structure type of composite shear wall is presented, the both sides of which are reinforced cement composite layer and the middle layer of which is concrete. In order to verify the cooperative work performance of cement-base composite layer and concrete, static load tests were carried out. In the test, the deformation properties of composite shear walls and the development law of the strain of concrete and steel were studied. Meanwhile, a normal shear wall with the same conditions was tested and the corresponding natures of two types of shear wall were contrasted and analyzed. The test results prove that the composite shear wall has a good overall deformation behavior, and can, to some extent, slow down the process of wall stiffness degradation. The research production has provided a foundation for the further exploration to the working properties of the composite shear wall under cyclic loading.

Abstract: This paper shows the corrosion of steel bar from a new perspective with viscoelasticity theory. The strain of steel bar is decomposed as initial elastic strain and creep strain, and the creep strain is caused by corrosion. In order to analysis creep strain, corrosion factor and corrosion strain function were introduced to reflect the deformation behavior. Then integral constitutive relation of corroded bar was deduced according to the above assumption. As a special case of this approach, the corrosion factor of steel bar in atmospheric environment is introduced. The results indicate that the corrosion factor increase with diameter deducing, and the deformation of the steel bar possess the acceleration creep behavior during the corrosion process.

Abstract: The purpose of this paper is to validate the accelerated testing methodology of a component from the field of aviation (supple platinum) using the standard calculation method and the analysis with finite elements. The specimens made out of supple platinum from the helicopter’s structure have been put through to accelerated experiments. Using the data resulted from the analysis with finite elements, the data resulted from resistance calculations and the experimental data obtained from the testing of specimens, a comparative study was realized between the specific strain and the normal stress that were obtained. From the results of this comparative study, it is obvious the fact that the method of analysis with finite elements is an efficient instrument to validate the experiments.

Abstract: In this paper, iron ladle stress and deformation has been accurately calculated using finite element analysis software ANSYS based on 260t iron ladle in standing, lifting, tipping working conditions. Distribution of stress field was obtained. The stiffness and strength of the iron ladle has been evaluated. The results show that the iron ladle in the standing, lifting and tipping working conditions, structural deformation is small, the strength and stiffness meet the requirements. This research extends the working life of 260t iron ladle. It provides theoretical basis for producing and using of the iron ladle and further optimal designing.