针对常规土工模型试验只能满足几何相似而不能满足应力相似的问题,提出了利用顺坡渗流力和坡面法向加载产生的法向应力以满足坡积土模型试验中自重应力相似的一种模型试验方法。对于很小厚度的坡积土模型,通过施加顺坡向渗流力满足切向应力的近似等效,施加垂直坡面荷载实现法向附加应力的近似等效,从而通过切向和法向应力的叠加来满足坡积土模型和现场原型边坡的自重应力相似。通过数值分析比较了厚为30 cm坡积土模型与厚为3 m坡积土原型。计算结果表明模型和原型的应力相似;模型和原型中的最大剪应变和剪应力水平在坡积体中的分布情况相似,数值误差在10%以内;数值分析结果验证了所建议方法的合理性和可行性。

The geometrical and stress similarity cannot be both satisfied in traditional soil model test. We put forwarda new soil slope model applied with tangent directional seepage and normal directional stress. For colluvial slope model of small thickness, the similarity of stress along slope and vertical to slope surface were satisfied respectively by applying seepage force and surcharge load vertical to the slope surface, thus self-weight of the soil slope model can be similar to that of the in situ slope. Numerical analysis was conducted to compare the stress and strain similarity of in situ slope (thickness of 3 meters) and slope model (thickness of 0.3 meter). The calculated result shows the area with stress and strain similarity in the soil slope model; the distributions of maximum shear stress and strain in the model and the in situ slope are similar, with the error less than 10%. The results verified the feasibility of the model test method.