构件并联法加固输电塔的试验研究及设计建议

输电塔易由于荷载过大、断线冲击或覆冰舞动而发生损伤和破坏.针对角钢塔的结构特点,在其原构件的侧面通过连接板及螺栓并联一根新的同规格角钢,以提高结构的承载力.对十字型、Z字型和T字型三种截面形式加固构件的承载性能进行了数值分析和试验研究,考虑了二次受力的影响,研究了加固构件的破坏过程、破坏模式和极限荷载,与单角钢构件的承载性能进行了对比分析,结果表明加固后新构件的承载力明显提高.借鉴钢结构加固技术规范,建议了加固构件稳定性设计计算公式,确定了加固折减系数的取值.

Study on strengthening the structure and its design for the transmission tower

Serious damage and collapse of transmission towers were easily induced by the ice disaster,wind disaster and so on.To improve the mechanical performance of the damaged tower assembled by angle-shaped members,an identical angle-shaped member is connected on the side of the existing angle-shaped member through steel plates and bolts.Several kinds of the composite section for the strengthened member are proposed,such as cross-shaped section,Z-shaped section,T-shaped section,and so on.The mechanical behavior of the strengthened member is discussed numerically and experimentally,and the failure mode and the ultimate load of each strengthened member are obtained,which demonstrate that the methods in this paper can strengthen the tower effectively.Based on the experimental results and the codes,the design formula for the stability of the strengthened member is given.