Through the bearing capacity test and finite element analysis of five nest light steel truss beams of different connection types,this paper made a study on the stress characteristics,failure mode and ultimate bearing capacity of nest light steel truss beam under vertical loads.The main factors which affect the flexural rigidity and ultimate bearing capacity of truss beam were also discussed.The result shows that the failure in truss beam mainly occurred at top chord near support or at mid-span due to the flexural or compression bending;the failure position will be changed by decreasing the distance between the first web member and support or using diagonal braces at the truss ends,but their effect on bearing capacity is not obvious;the ultimate bearing capacity of truss beam will be obviously increased after increasing cross section area of the top chord,but the change of bending stiffness of beams is little;the error of deflection simulation analysis is large with node rigid assumption,while results between simulation analysis and experimental values are more close with node semi-rigid assumption;the design of truss beam is mainly controlled by its mid-span deflection,the normal service bearing capacity of the truss beam can only reach 33~45 percent of ultimate bearing capacity.

框架梁-剪力墙直交节点常应用于高层钢筋混凝土建筑中的框-剪结构体系和框架-核心筒结构体系。文章以钢筋混凝土框架梁-剪力墙直交节点为研究对象,对此进行了试验方案的设计,并运用ABAQUS有限元分析软件,对该节点进行简化的弹性有限元模拟分析(梁简化为三维实体单元,剪力墙简化为壳单元),并得出相应的分析结论。

Objective To construct a three-dimensional (3-D) finite element hip model including acetabular bone, cartilage, labrum and bone, cartilage of femoral head based on Chinese visible human dataset for biomechanics. Methods The images of hip dataset in Chinese visible human (CVH) were obtained for construction of hip biomechanical model. A hip model including acetabular bone, cartilage, labrum and bone, cartilage of femoral head was constructed with AutoCAD and Solidworks software by using these images. The hip model was imported into ABAQUS analysis system for meshing of the hip joint contact surface, and then loading test (400 N) was performed at 5 hip flexion and 20 external rotation. The contact pressure distribution on the cartilage and labrum was observed. Results The constructed 3-D hip model reflected the real hip anatomy. The constructed 3-D finite element hip model reflected biomechanical behavior similar to the results from previous researches. Conclusion The hip dataset of CVH can be used for accurate 3-D reconstruction. The construction of the 3-D finite element hip model can avoid some disadvantages by other construction methods, such as imprecision of cartilage construction and absence of labrum, and hence can provide basic data which are critical for accurately modeling normal loads as well as for observation of abnormal conditions of the hip.