斜坡地基附加应力分布规律模型试验及数值模拟

不少山区输电线路的铁塔基础都建在斜坡上，研究斜坡地基内附加应力的分布规律很有必要。采用室内模型试验和数值模拟相结合的方法，研究了临坡距对斜坡地基附加应力分布及扩散规律的影响。研究成果表明，当临坡距小于安全距离时，地基附加应力随临坡距的增大而增大，并在基础两侧具有显著的非对称性；当临坡距超过安全距离时，附加应力逐渐趋于稳定，基本接近平面地基状态。传统的平面地基附加应力计算方法不适用于斜坡地基，当临坡距在0.3 m时，地基浅层附加应力接近平面地基条件的50%，说明斜坡对地基附加应力的影响十分显著。在小临坡距条件下地基附加应力较小，但对应的地基变形却较大，也说明传统的分层总和法不适于计算斜坡地基变形，否则将影响工程安全。在地基稳定性满足要求的前提下，建议最小临坡距不小于安全距离。

Experimental study and numerical simulation on additional stress distribution of foundation adjacent to slopes

Many electric transmission tower footings built on the slopes in mountainous area, it is necessary to study the additional stress distribution of slope foundation. In this paper, model tests and numerical experiments are used to research the influence on stress distribution and diffusion regularity of the additional slope foundation induced by the distance from the top of the slope. Results of the model test show that the distance from the top of the slope has a great impact on the additional stress in soil. Additional stress increases with the increase of the distance from the top of slope and has obvious asymmetry on both sides of the foundation when it is less than the safe distance. Additional stress gradually stabilized, close to the level ground state when the distance from the top of slope is more than the safe distance. When the distance from the top of slope is 0.3 m, additional stress in shallow soil is close to 50% of the plane foundation condition, the influence of additional stress in soil slope is very significant; and traditional additional stress calculation method is not applicable to slope foundation. In the small distance from the top of slope conditions, the additional stress is small; but the corresponding ground deformation is greater; it is proved that the traditional layerwise summation method is not suitable to calculate the deformation of the foundation in the slope. Otherwise, it will affect the safety of engineering. In the case of foundation stability meet the requirements, it is recommended that the minimum distance from the top of slope is not less than the safe distance.