土钉墙技术在坡、残积土边坡支护中的应用

结合工程实例，阐述了坡、残积土层中边坡土钉墙支护的设计与施工要点，并针对施工过程中出现的特殊情况，提出相应的解决方案与处理措施。     

基于非线性有限元方法的复合土钉支护影响因素研究

复合土钉支护是近年来发展起来的一种基于土体自承的新型挡土结构,广泛应用于土体开挖和边坡稳定。利用非线性有限元方法,针对土钉支护体系的结构特征和施工过程,引入带转动自由度的Goodman接触面单元,并结合实例对水泥搅拌桩复合土钉支护体系进行研究,得到土钉、搅拌桩等相关设计参数的变化对基坑位移、土钉受力的影响规律。     

降雨诱发非饱和土边坡直线滑移的稳定性计算

根据Green-Ampt入渗原理,考虑降雨入渗及其对土体的物理力学作用,分析了雨水入渗非饱和土边坡坡面入渗规律,建立了非饱和土边坡坡面入渗模型,获得了雨水非饱和入渗过程中的雨水入渗深度计算式。通过分析降雨后边坡潜在滑移体的几何模型和力学特性,获得了滑移面倾角与边坡倾角、雨水入渗深度和坡高之间的关系,建立了降雨入渗影响下非饱和土边坡直线滑移与倾覆破坏的安全系数计算式,为分析降雨入渗非饱和土边坡稳定性提供了一种定量计算方法。     

软土基坑复合土钉支护的数值分析与工程应用

从复合土钉支护在软土基坑中应用阐述了复合土钉支护的作用机理,采用有限元数值模拟方法对基坑开挖与复合土钉支护的施工全过程分别进行了分析,通过工程实例的计算进一步验证了复合土钉支护在控制软土基坑位移上的可行性,并且得到了令人满意的结果.     

深基坑边壁土钉支护监理

深基坑土钉支护是全新的支护方法,施工监理重点,弄清土钉支护的基本原理,突出旁站监理的作用,实施全过程的质量控制。     

土钉支护技术在深基坑支护中的应用

土钉支护技术是一种近几年发展起来的新的深基坑支护技术,与传统的基坑支护体系相比,具有造价低廉,安全可靠且工期短、经济效益显著等特点.本文根据工程实例介绍土钉支护的设计方法和施工方法.     

深基坑土钉支护设计探析

本文介绍了土钉的特点及适用范围，分析了土钉的作用机理，重点阐述了土钉的设计内容。并在实际工程中应用。取得良好的效果。     

预应力锚杆复合土钉支护三维非线性分析

应用三维非线性有限元分析通用软件,对基坑工程中采用预应力锚杆复合土钉支护和单纯土钉支护2种支护方式进行数值模拟分析,包括分步土方开挖、土钉安设与面层制作等全过程的施工模拟,对同等工况下的单纯土钉支护和预应力锚杆复合土钉支护进行力学性状比较,包括坑外土层张拉应力区分布、变形特征、支护坑壁力学特征和土钉与锚杆拉力分布等方面的差异性,并结合复合土钉支护基坑工程应用情况,系统地研究了预应力锚杆复合土钉支护作用机理及其工作性能.     

土钉支护技术在路基高边坡防护工程中的应用

介绍土钉支护技术的机理和一般设计方法，结合赣龙铁路DK123 819～ 995段高边坡路基防护工程，阐述了土钉支护技术在实际工程中的应用。     

Finite element reliability analysis of slope stability

The method of nonlinear finite element reliability analysis （FERA） of slope stability using the technique of slip surface stress analysis （SSA） is studied. The limit state function that can consider the direction of slip surface is given, and the formulations of FERA based on incremental tangent stiffness method and modified Aitken accelerating algorithm are developed. The limited step length iteration method （LSLIM） is adopted to calculate the reliability index. The nonlinear FERA code using the SSA technique is developed and the main flow chart is illustrated. Numerical examples are used to demonstrate the efficiency and robustness of this method. It is found that the accelerating convergence algorithm proposed in this study proves to be very efficient for it can reduce the iteration number greatly, and LSLIM is also efficient for it can assure the convergence of the iteration of the reliability index.     

高陡岩土边坡有限元分析

本文以高陡岩土边坡实测资料为研究对象,遵循资料收集—现场调研—模型建立—程序设计—工程分析的研究思路,采用有限元强度折减数值分析方法,通过前后处理软件,综合考虑土性参数和边坡边界条件的变化,从计算结果中分析边坡的位移,变形及其塑性发展趋势和安全系数。     

平板式半挂车车架有限元分析

应用Pro/E对平板式半挂车车架进行三维实体建模。对该模型进行简化处理、抽中面和修补后导入ANSYS。采用壳单元建立平板式半挂车车架的有限元模型,对车架进行静力分析和模态分析。结果表明,车架在弯曲和扭转工况下,刚度和强度满足要求;车架结构的低阶模态频率不在路面激励频带之内,不会产生共振现象。     

Finite element analysis of internal gear in high-speed planetary gear units

The stress and the elastic deflection of internal ring gear in high-speed spur planetary gear units are investigated. A rim thickness parameter is defined as the flexibility of internal ring gear. Six evenly spaced linear springs are used to describe the fitting status between internal ring gear and the gearcase, The finite element model of the whole internal ring gear is established by means of Pro/E and ANSYS. The loads on meshing teeth of internal ring gear are applied according to the contact ratio and the load-sharing coefficient. With the finite element analysis （FEA）, the influences of flexibility and fitting status on the stress and elastic deflection of internal ring gear are predicted. The simulation reveals that the principal stress and deflection increase with the decrease of rim thickness of internal ring gear. Moreover, larger spring stiffness helps to reduce the stress and deflection of internal ring gear. Therefore, the flexibility of internal ring gear must be considered during the design of high-speed planetary gear transmissions.     

壳梁组合结构自由阻尼处理有限元分析

构造了壳梁组合结构自由阻尼处理薄板结构的有限元模型, 将板单元的节点作为主节点, 梁单元的节点作为从属节点, 推导出相应的刚度矩阵和质量矩阵. 在用有限元法进行结构动态特性分析的基础上, 用模态变形能法估算了结构的模态损耗因子. 最后以一计算实例将本文方法所得结果与用ANSYS软件计算所得结果进行了比较, 结果表明本文方法计算效率高、简单可行, 且具有较高的精度和工程实用性.     

超长混凝土结构硬化阶段温度作用有限元分析

超长混凝土结构硬化阶段的裂缝,由于影响因素的复杂性和结构的空间效应,很难采用手算法进行定量运算.利用ANSYS有限元程序建立瞬态温度场的分析模型,并对北京某实验用房在混凝土硬化阶段温度场和应力场进行了数值计算分析.计算结果表明混凝土经历了先压后拉的受力过程,温度应力由结构的两端向中心逐步增大,并与结构长度相关.在施工中采取必要的保温和散热措施、合理控制结构内的温度梯度,就可增加设缝间距,并避免裂缝产生.     

Finite volume method based on the Crouzeix-Raviart element for the Stokes equation

The author provides a new discretization method-the finite volume method(FVM). For the Stokes equation the velocity space is approximated by the nonconforming linear element based on the dual partition and the pressure by the piecewise constant based on the primal triangulation. Under the suitable smoothness of the solution, the optimal convergence rateO(h) is obtained, whereh denotes the parameter of the space discretization. Project supported by Natural Science Foundation of Zhejiang province.     

Finite element analysis of dynamic response and structure borne noise of gearbox

A dynamic finite element method combined with finite element mixed formula for contact problem is used to analyze the dynamic characteristics of gear system. Considering the stiffness excitation, error excitation and meshing shock excitation, the dynamic finite element model is established for the entire gear system which includes gears, shafts, bearings and gearbox housing. By the software of I-DEAS, the natural frequency, normal mode, dynamic time-domain response, frequency-domain response and one-third octave velocity grade structure borne noise of gear system are studied by the method of theoretical modal analysis and dynamic response analysis. The maximum values of vibration and structure borne noise are occurred at the mesh frequency of output grade gearing.