采动区不同地基条件对复合防护板厚度的影响规律

Influence Regularities of Different Foundation Conditions in Mining Subsidence Area on the Thickness of Composite Protective Plate

以山西省某500kV超高压典型双回路输电线路中的SZC1直线塔为原型,考虑地基—基础—上部铁塔结构的共同作用,研究了不同地基土体性质以及复合防护板基础的防护板厚度对上部结构受力和变形的影响规律。研究表明,不同地基土情况下,结构支座位移与上部最大应力均随板厚增大而逐步减小。板厚相同时,不同地基土对应的位移与应力大小依次为:可塑<硬塑<坚硬,即内聚力越大、摩擦角越大时其值越大。

Taking a SZC1 straight line tower in double circuit of typical 500 kV EHV transmission line in Shanxi as the prototype,and considering the combined action of ground, foundation, and the upper structure of tower,the influence regularities of different foundation conditions and the thickness of composite protective plate on the stress and deformation of the upper structure were studied. The results show that the displacement of structural support and maximum stress of upper structure decreases gradually with the increase of plate thickness at cases with different foundation soil. When the thickness of composite protective plate is the same, the displacement and stress with different foundation soil is different. Hard soil is the largest, and hard plastic soil is the second, and plastic soil is the least. In other words,the greater the cohesion and friction Angle, the bigger the displacement and stress is. The reasonable thickness of composite protective plate should be between 400~600 mm for the typical double circuit transmission tower. When the foundation soil is hard, its thickness can be thicker appropriately.