输电线路原状土基础抗倾覆特性数值模拟研究

输电线路杆塔基础一般承受较大的水平力和倾覆力矩作用,抗倾覆稳定性往往成为杆塔基础设计的控制因素。采用有限元程序,数值模拟等直径、扩底桩和扩顶桩 3种桩型的抗倾覆特性,结果表明:在倾覆荷载作用下掏挖基础桩属刚性短桩,可按照刚性短桩“m法”设计计算;可以从提高桩土体系抗倾覆承载力和提高基础本身强度与刚度(例如采用扩底桩或扩顶桩)2个方面,来提高杆塔基础的抗倾覆能力。

Numerical Simulation on Anti-overfurning Characteristics of Undisturbed Soil Foundation in Transmission Line

The foundations of transmission towers normally can withstand relatively large horizontal forces and overturning moments. Overturning resistance is the key factor of tower foundation design. FEM code was used to simulate the overturning resistant characteristics of three types of foundation designs, such as equal-diameter, belled pile and enlarged top pile. Numerical simulation results indicate that under the overturning loads, the base pile can be treated as rigid short pile, thus the "m method" can be applied in calculation; the overturning resistance can be improved by increasing soil load bearing capability and foundation strength and stiffness (e.g. using belled or enlarged top pile).