【摘要】 钢管外圈螺栓连接的常规刚性法兰连接形式难以满足高度高、荷载大的大跨越钢管塔连接承载力要求,提出一种新型内外双圈法兰节点形式来解决传统刚性法兰的承载力不足。以某大跨越塔为背景,设计内外法兰的缩尺模型试验,开展了纯弯荷载下内外法兰的承载性能试验,考察其承载力特点、传力机理及计算理论。分析荷载增大过程中主管、连接螺栓应变的变化情况,得到法兰连接界面上的中和轴、旋转轴位置及内外螺栓内力分布规律。同时,建立内外法兰的非线性有限元模型分析内外法兰承载力特性,重点考察了连接螺栓的传力特点。基于试验及有限元分析结果可知:随着荷载的增大,法兰板间发生张开,螺栓发生颈缩破坏;内外法兰的抗弯承载力设计时,连接螺栓旋转轴位置可取距离管中心0. 6R处(R为主管半径)。更多还原

【Abstract】 Traditional rigid flange with bolts connection outside pipe can hardly meet the bearing requirements of highaltitude,big-load and long-span steel tube towers. A new-type inner-outer double layered flange was presented to overcome bearing deficiency of traditional rigid flange. In order to achieve the bearing capacity,transmission mechanism and theory of computation of the flange,pure bending test was carried out on a scale specimen used in a certain large crossing steel tube tower. By analyzing the variation of the strain distributions on the tube and bolts with the increase of load,the locations of neutral axis and rotational axis were achieved. In addition,the distribution rule of the internal forces in both inner and outer ring bolts was revealed. Meanwhile,the nonlinear analysis for simulating the static behavior was also conducted by finite element models,and paid emphasis on the force transfer characteristics of bolts. According to the results of test and FEM analysis,when the load upper and lower flange plates were separated and bolts failed as the load increased. When designing the bearing capacity of inner-outer flanges,the rotational axis of bolt is suggested be 0. 6 R( R is the radius of the tube)distance from the centerline of the tube.更多还原