为了研究端部角焊缝与高强度螺栓并用连接结构在循环荷载下的疲劳性能,通过试验,对比了焊接和栓焊两种不同连接结构疲劳寿命和疲劳失效机理的差异,分析了高强度螺栓对栓焊结构疲劳寿命的影响。结果表明,高强度螺栓能够减小焊缝处的受力,抑制裂纹扩展,提高结构连接刚度,有效延长结构的疲劳寿命。同时利用等效结构应力法对栓焊结构进行了寿命估算。估算结果与试验结果吻合良好,误差在10%以内,验证了等效结构应力法对端部角焊缝与高强度螺栓并用连接结构寿命估算的适用性。
In order to analyze the fatigue property of co-use joint with transverse fillet weld and high-stress bolts, fatigue test was performed to contrast fatigue life difference and fatigue mechanism between weld joint and co-use joint. Then the influence of the high-stress bolt on the fatigue life of co-use joint was obtained and the results show that high-stress bolt can effectively extend the fatigue life by reducing the force of weld and restraining the crack propagation which increases the connection stiffness of structure. Meanwhile, the fatigue life of co-use of weld and bolts joint was estimated via equivalent structural stress method. The estimation results was in a well agreement with the test results and the error was less than 10%. It indicated the applicability of equivalent structural stress method to estimate the fatigue life of co-use joint with transverse fillet weld and high-stress bolts.