基于Bentley平台的内河高桩码头桩基参数化设计模块开发与应用*

针对内河高桩码头应用BIM技术的建模精度和建模效率难以保证的问题,采用VisualStudio 2017,通过C++、C#(Addin)、C++/CLI混合编程等开发手段,在Bentley的Microstation图形平台进行二次开发,研发适用于内河高桩码头桩基参数化设计的BIM软件模块。模块包含高桩码头平台轴网自动设计、创建轴网平面图、图形及模型预览、桩基参数化建模、桩基参数导入、导出及桩基参数表汇总等功能。通过直观化地输入模型创建所需的参数集,实现高精度、高效率的桩基参数化三维设计,从而简化一类模型的创建过程,体现了BIM技术在参数化设计、模型可视化统计工程量等方面的应用优势。     

基于AutoLISP的S型辐板车轮交互式参数化设计

基于轨道车辆S型辐板车轮结构的几何形状特点,在AutoCAD平台上利用其二次开发环境Visual LISP,使用AutoLISP和DCL语言设计出2种S型辐板车轮的交互式参数化模型对话框,实现在S型辐板车轮结构几何形状优化设计过程中,改变所需参数即可自动生成S型辐板车轮的二维截面图,避免了因车轮结构几何形状改变导致重复绘制截面二维CAD图的缺点,显著提高了S型辐板车轮的绘图效率,为车轮结构三维建模和结构FE应力分析提供了基础几何模型。     

Prediction of the interaction between a simple moving vehicle and an infinite periodically supported rail – Green's functions approach

This paper herein describes the interaction between a simple moving vehicle and an infinite periodically supported rail, in order to signalise the basic features of the vehicle/track vibration behaviour in general, and wheel/rail vibration, in particular. The rail is modelled as an infinite Timoshenko beam resting on semi-sleepers via three-directional rail pads and ballast. The time-domain analysis was performed applying Green's matrix of the track method. This method allows taking into account the nonlinearities of the wheel/rail contact and the Doppler effect. The numerical analysis is dedicated to the wheel/rail response due to two types of excitation: the steady-state interaction and rail irregularities. The study points out to certain aspects regarding the parametric resonance, the amplitude-modulated vibration due to corrugation and the Doppler effect.     

摆线齿轮加工节圆为任意值时滚刀齿形曲线的计算

本文以点齿代换法为媒介,从运动学和几何学出发,导出了摆线针轮减速器中摆线齿轮在任意加工节圆时,计算滚刀齿形曲线的通用方程式,此方法避免了现行啮合计算法中繁杂的微积分等数学运算,是一种较为简便的计算方法.     

搅拌筒螺旋线平面展开方程及基于UG的参数化表达式

推导出搅拌运输车搅拌筒对数螺旋线平面展开方程,用UG的参数表达式来实现螺旋线和在平面上展开曲线的生成。     

比例延迟微分方程线性多步法的散逸性

考虑了比例延迟微分方程的数值方法的散逸性,把一类线性多步法应用到以上问题中,得到了该数值方法的散逸性结果。     

Method to calculate resistance of high-speed displacement ship taking the effect of dynamic sinkage and trim and fluid viscosity into account

A method is presented to calculate the resistance of a high-speed displacement ship taking the effect of sinkage and trim and viscosity of fluid into account. A free surface flow field is evaluated by solving Reynolds averaged Navier-Stokes (RANS) equations with volume of fluid (VoF) method. The sinkage and trim are computed by equating the vertical force and pitching moment to the hydrostatic restoring force and moment. The software Fluent, Maxsurf and MATLAB are used to implement this method. With dynamic mesh being used, the position of a ship is updated by the motion of ??ship plus boundary layer?? grid zone. The hull factors are introduced for fast calculating the running attitude of a ship. The method has been applied to the ship model INSEAN2340 for different Froude numbers and is found to be efficient for evaluating the flow field, resistance, sinkage and trim.     

Design of Continuous and Discrete LQI Control Systems with Stable Inner Loops

Design approaches were proposed for both continuous and discrete LQI (linear quadratic with integral) controllers, if exist, to stabilize the inner loops in addition to stabilizing the closed loops and minimizing the quadratic cost functionals. Derived from the algebraic Riccati equations involved in continuous and discrete LQI control, the design approaches were straightforward obtained by setting the quadratic cost functionals to decoupled forms with positive definite weighting matrices. Examples were provided to verify the effectiveness of the approaches.     

离散型具有时滞复Volterra方程出现4-周期轨道解的条件

给出具有时滞复Voherra方程的离散型,讨论了离散型具有时滞的复Volterra方程出现4-周期轨道解的条件,并证明了系统存在与此4-周期轨道解一致的4-周期的初始函数对．     

刘家峡大桥重力式锚碇温度场参数化分析

以西北地区最大跨度单跨悬索桥—刘家峡大桥为工程背景,利用ANSYS有限元软件,建立了考虑大地、环境温度场热交换及冷却水管效应的全三维、浇筑养护全过程有限元仿真模型,介绍了混凝土水化热、热对流边界条件等模拟技巧;详细分析了考虑当地气温变化特点及冷却水管效应时按分层厚度1.5m,3.0m浇筑混凝土的结构温度场、应力场的分布规律,实际施工采用1.5m厚度分层浇筑,在理论分析所得关键区域埋设了温度、应力传感器,实测温度场、应力场结果与理论分析数值吻合良好,映证了所建立的水化热分析有限元模型、对流边界条件以及冷却水管效应正确无误,理论分析成果指导施工,实测结果验证了理论分析的正确性,分析方法及有限元建模技巧可为同类工程提供借鉴.