点焊结构接头应力应变场的数值模拟

以汽车点焊结构为研究对象，通过合理建立点焊结构的有限元离散模型和力学模型，系统分析了点焊搭接剪切拉伸试样在不同载荷下的应力应变分布规律，以及应力应变与结构、载荷间的对应关系，获得了理想的数值模拟结果。     

三滩黄河大桥0#块空间应力分析

本文对连续刚构桥箱梁在施工阶段各工况下0#决顶板、底板、腹板和横隔板作了空间应力分析,计算中计入了收缩、温度和时间效应的影响,对不同施工方法作了对比分析,从而获得施工过程次应力的准确分布规律,为0# 块优化设计积累了经验。     

CA488发动机连杆应力计算与测量

论述了ＣＡ４８８发动机连杆断裂原因及采取的相应措施，并且通过有限元计算及实际测量，比较了三种断面结构的连杆相关位置的应力大小，为解决ＣＡ４８８发动机连杆断裂问题提供了理论根据及数据。     

Reinforcement Effect of Corrugated Steel on the Bearing Capacity of Embedded Concrete-Lined Corrugated Steel Structure北大核心CSCD

Embedded concrete-lined corrugated steel (CLCS) has been widely used in many fields such as cutand- cover tunnels and shed-tunnels. However, fewer research works have been done about CLCS, and the contribution of corrugated steel (CS) to the bearing capacity of CLCS is not considered, causing a greater concrete lining thickness and higher cost. In this study, the reinforcement effect of CS was analyzed with numerical simulations by comparing the two models, in one of which the bearing capacity of CS was considered while the other was not. It is found that the stresses and deflections at the trough section are larger than that at the crest and middle parts; the maximum tensile stress of CLCS from the spandrel to the vault is approaching to the tensile strength and the deflection is higher; the maximum compressive stress of CLCS from the arch foot to the spandrel is close to the compressive strength and the deflection is lower. Moreover, it is an obvious reduction of the stresses and deflections at different sections and circumferential positions due to the contribution of CS. This indicates the reinforcement effect of CS should be taken into account to reduce lining thickness. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.     

某散货船舱口围肘板趾端开裂原因及节点优化方案分析

文章首先分析了某46 000 DWT散货船纵向舱口围端部肘板趾端开裂的原因,根据分析结果提出了节点优化方案;采用有限元直接计算的分析方法比较了修改前后节点的应力状况,并进行验证;提出了舱口围端部肘板修复时切割、装配和焊接的要求。研究结果为散货船舱口围板高应力区域的节点设计提供了理论和实船验证依据。     

基于大直径盾构隧道扩挖地铁车站的结构方案及其关键节点受力和变形

针对北京地铁14号线将台车站结构方案存在的不足,提出1种基于大直径盾构隧道扩挖地铁车站的塔柱式结构方案,并建立三维非连续接触模型,研究塔柱式结构关键节点的受力和变形.结果 表明:盾构隧道和车站2边主体结构的施工,对管片纵缝的张开和错台影响显著,但对管片环间错台影响不明显;横通道施工对管片纵缝的张开和错台影响较小,开口环...     

超载作用对沥青路面结构的力学影响研究

分别通过轴载换算和超载作用下路面的力学分析两方面分析了超载对路面各层层底应力和路表实测弯沉的影响,进而解释了重载路段路面易损坏的力学机理.     

Structural Damage Identification via Pseudo Strain Energy Density and Wavelet Packet Transform

Based on strain signals,a new time-domain methodology for detecting the beam local damage has been developed.The pseudo strain energy density (PSED) is defined and used to build two major damage indexes,the average pseudo strain energy density (APSED) and the average pseudo strain energy density rate (APSEDR).Probability and mathematical statistics are utilized to derive a standardized damage index.Furthermore,by applying the analytic relation between the strain energy release rate and the stress intensity factor,an analytic solution of crack depth is derived.For the dynamic strain signals,the wavelet packet transform is used to pre-process measured data.Finally,a numerical simulation indicates that this method can effectively identify the damage location and its absolute severity.     

Generalization of Results of Computations and Natural Experiments at Steel Parts Quenching

IntroductionThepaPerpresentsthegenera1izationofresultsofnumericalcomputationsandnaturalexperimentsbasedonthesimilaritytheoryandtheoryofregularthermalconditions.Thenumericalcomputationshasbeenmadeonthebasisofsolvingequationsofnon-stationarythermalconductivityandthermoplaSticity.Thegeneralizationofresultsliesinthefactthatwefoundadimensionlessformulaforthedeterminationofthetimeofreachingthemaximumcompressionstressesonthesurfaceofp8rtstobequenched.ThepatstobequenchedaredividedintothreegrouPs:pla…     

施工期仿真分析在船闸廊道工程中的运用

船闸廊道是混凝土裂缝易发部位,文章依托施桥三线船闸工程,采用大型有限元分析软件ANSYS对施工期廊道进行仿真分析,通过对施工期温度场、应力场的仿真计算和结构优化研究,探讨了廊道温度场、应力场分布规律及随时间的变化规律,为施工期廊道混凝土裂缝的控制提供理论依据。