Papers by Keyword: Displacement

Abstract: In this paper, we propose a signal compensation algorithm. In heterodyne laser interferometer, the unexpected error restricts the precision such as nonlinearity and environmental error. To improve the accuracy in length measurement, we use the method of Lagrange multiplier which solves the constrained optimization problem and allows to minimize an objective function. With the method of Lagrange, we apply it to a length measurement and show the result of simulation.

Abstract: This work consist to make a dynamic study of an actual structure sized before applying Moroccan seismic regulations RPS2000, the study will be made using the SAP2000 software and exploiting accelerograms of Al Hoceima’s earthquake occurred on 24^th February 2004, this earthquake was recorded at several Spanish stations this analysis will first identify some dynamic characteristics of the studied frame like eigenmodes of the frame and the maximum displacement of the terrace. The use of several accelerograms will highlight the influence of distance on the intensity of the earthquake and will give some information about sol-structure interaction

Abstract: Creep landslide tunnel deformation is a diversity,changeability, less information, complicated nonlinear problem, it’s unable to establish accurate mathematical model.A creep landslide tunnel deformation prediction model based on SVM was constructed in this paper to enhance prediction accuracy, and penalty parameter c and Kernel function parameter g of SVM were optimized by genetic algorithms (GA).nine closely related factors in creep landslide tunnel deformation were selected as Input vector of SVM , creep landslide tunnel deformation measured value as a model target output. In Matlab 2011b simulation software,80 groups observation data from 2012 to 2013 of Laoyeling tunnel in Changchun to Hunchun highway of Jilin province as the sample data, 70 groups were used as training set, other 10 groups were used as testing set. The simulation result shows that testing value is very close to the true value in this method, the average relative error close to 2%. Effectiveness of the creep landslide tunnel deformation prediction based on GA_SVM model is verified by experiments.

Abstract: Dam deformation is a multivariate complicated and nonlinear problem, it’s unable to establish accurate mathematical model.A dam deformation prediction model based on RBF neural network was constructed in this paper to enhance prediction accuracy. Three closely related factors in dam deformation are hydraulic components, temperature component and aging components ,they were selected as Input vector of RBF neural network, dam deformation measured value as a model target output. In Matlab 2011b simulation software,50 groups Fengman dam quantitative observation data from 2012 to 2013 as the sample data,45 groups were used in RBF neural network model training, other 5 groups were used in testing for the model. The simulation result shows that testing value is very close to the true value in this method, the average relative error close to 3%. Effectiveness of the dam deformation prediction based on RBF neural network is Verified by experiments.

Abstract: This paper presents advanced modeling and simulation methods, using the latest generation of CAD-CAE applications. For the geometric modeling of human knee joint embedded applications as DesignModeler, SpaceClaim under Ansys Workbench software package were used. The objective of this study is to present our contributions on the modeling, simulations and finite element analysis of the healthy and osteoarthritic human knee joint in order to quantify and investigate its biomechanical behavior. The main objective of this article is to present a complex three-dimensional model of the healthy knee joint and of the osteoarthritic joint which shows a 15^o tilt in varus, the joint being affected by osteoarthritis in both compartments, in order to predict stresses and displacements in their individual components. The applied forces were equal with 800 N and 1500 N. Finally the results obtained for normal knee and for OA knee joint are compared.

Abstract: The design of the housings of the gear reducers is made, usually, using empirical equations based on the center distance (the distance between shafts). These equations can lead to inappropriate stresses distribution and inadequate material consumption at the final product. In the manufacturing of large series and in the manufacturing of the gear reducers/ gearboxes with large dimensions it is necessary an optimization of the housing dimensions. The use of the finite element analysis in this process, combined with experimental researches, can generate significant improvements. The paper is focused on the analysis of stresses distribution and displacements on the housing of a two-stage helical gear reducer with parametric dimensions and loads. The housing is subjected to a static finite element study. The optimization process aimed to minimize the total weight of the housing. The next features were submitted to dimensional changes: the thickness of the housing walls and the thickness of the ribs. The results presented as diagrams of stresses and displacements distributions show real opportunities to reduce the total weight of the housing and the material consumption.

Abstract: The paper presents the study of the stresses and the displacements that appear in different areas of the removable partial denture (RPD) with extracoronal attachments under occlusal loading, using FEA. The first step was to create the 3D model of a RPD with ball attachments in case of a class I Kennedy edentulous patient with all six anterior teeth as abutments. All materials were considered homogeneous, isotropic and having linear elasticity. There were assumed two types of constraints: in the first one the model is fixed under the action of the mastication forces; in the second one the rotational movement of the denture’s saddles in the sagittal plane was simulated, towards the edentulous ridge. In the first case, the 3D model and FEA were developed using Autodesk Inventor 2013 software. In the second case, the FEA was done using Autodesk Algor Simulation software. The loading of the model was symmetrically applied, considering the magnitude of the tangential and normal oral forces determined by Las Casas et al. These forces were applied to all the PM1, PM2, M1 and M2 pairs. Each loading case was analysed separately. The results of the two constrain situations are presented graphically, comparatively and show that the amount of the saddle displacement depends on the application area of the mastication force. Maximum displacement was computed at the application of the mastication forces on the M2 and decreases as the force is applied more mesial. The amount of the major connector’s deformation is very little influenced by the site of the force. The largest displacement of the denture was recorded at the distal end of the saddle, with values ​​that depend on the site of the forces. The existence of the rotational movement of the denture’s free end saddles in the sagittal plane, towards the edentulous ridge, changes the values ​​of accumulated stresses in denture during mastication and its Von Mises stress peaks. This analysis can be use to establish the principles of planning and designing the RPD with ball attachments having in mind to minimize the number of repairs caused by fractures of the components.

Abstract: Based on the engineering background of Beijing unban groundwater levels rebounded, the stress behavior of subway station structure under cases of the groundwater in different water levels from the view of numerical mechanical models is researched in this paper and the working condition of this paper is the actual engineering of the Beijing subway line 10. The results demonstrate different underground water levels could lead to obvious vertical displacements, plastic changes of surrounding soil sand the groundwater level upturn obviously within a certain range make the underground structures deform and float overall. Some conclusions are important references for the further improvements of the design and construction of underground structures, reinforcement of existing substructures.

Abstract: The entity model of slope arch framework in highway was monitored in stress and displacement at different time. Though the date of different points collected, the mechanical mechanism can be studied, and the analysis was done between calculation results and entity model. The studying results show that the stress of point were increasing at first and then mitigating, and the stress increase undulating as the distance from the slope top increase. The date of monitor and finite element analysis model indicate that the point on the arch toe is the worst stress place, and the total displacement increase nonlinear as the distance from the slope top increases, and the bump phenomenon exists in the bottom of slope, the points are likely to be broken.

Abstract: In this paper, based on the theory of ship-bridge collision, large-scale finite element software ANSYS is adopted to establish the calculation model of the bridge.According to the specification of our country, the calculation of bridge collision force then compares with the actual situation.Through the calculation of collision force, the ship-bridge collision is transformed into the problem of transient analysis of collision point.This article is mainly to analyze the change of bridge energy and the stress and displacement of main parts of the bridge. Finally, this article puts forward the personal vision.