A Study on the Earth Pressure Distribution around the Trap Door

(1)对于桑迪和粘性土地基，均可以数值模拟活板门周围的土压力分布。(2)特别是，在粘土地基的情况下，土压力得到了高精度。(3)阐明了双折射效应的重要性，指出了流动规则的选择应慎重。(4)对砂土和粘土的复合地基进行了试验和数值模拟，但由于粘土的刚度较大，双层地基的效果不明显。(5)数值模拟结果表明，当软粘土层沉积在砂层下时，几乎没有释放的土压力。(6)太沙基公式不能很好地预测复合土层的土压力。

(1) The earth pressure distribution around the trap door can be numerically simulated for both of sandy and clayy grounds.(2) In particular, the earth pressure in the case of clayy ground is obtained with a high accuracy.(3) It is clarified that the effect of the dilatancy is important and that the selection of thye flow rule should be made carefully.(4) An experiment as well as the numerical simulation was performed for the composite ground of clay and sand but any clear effect of the double layr ground was not observed due to the high stiffness of clay.(5) From the result of the numerical simulation, it was found that almost no loothed earth pressure was observed when the soft clay layr is deposited under the sand layr.(6) The Terzaghi's formula can not predict clearly the earth pressure for the composite layr.