单层柱面网壳铸钢节点承载力试验研究

Experimental Study on Bearing Capacity of Cast Steel Joints in a Single-layer Cylindrical Reticulated Shell

针对单层柱面网壳梯形截面铸钢节点进行承载力试验研究,考察次梁是否加肋对铸钢节点强度和刚度的影响。采用ANSYS程序中Solid45单元进行有限元分析,在破坏模式、变形过程及节点承载力方面与试验结果进行对比分析。试验结果与数值结果吻合较好,说明了有限元分析的可行性。试验表明,未经加固的节点在1.0倍设计荷载作用下开始屈服,2.0倍设计荷载作用下节点域大面积屈服,不适宜继续承受荷载;加固的节点在2.0倍设计荷载作用下基本处于弹性状态,并且加固后节点刚度有较大提高。

Experimental study has been carried out on cast steel joints with trapezoidal cross-section of a single-layer cylindrical reticulated shell.Different joints of secondary beams with or without stiffener have been studied as influence factors.The author employs nonlinear finite element method with eight nodes solid element in ANSYS program to examine the mechanical behavior of joints.Solid FEM is validated as an efficient method of predicting ultimate bearing capacity of the joints through comparing failure modes,deformation process and the ultimate bearing capacity with test results.The results show that,the joints without stiffener begin to yield at the main beam web under 1.0 time of the design load.A large area of joint region is found yielding under 2.0 times of design load and the joint is not appropriate to continue to bear the load.The joint with stiffener is in elastic state under 2.0 times of design load.It also shows that stiffener can obviously improve the stiffness of the joint.