抛石爆破挤淤过程的有限元数值模拟

Finite Element Simulation to the Process of Explosion Replacement

抛石爆破挤淤的过程主要分为4步。第1步是直接进行抛石挤淤;第2步是在堤头前方的淤泥内进行首次堤头爆破,使淤泥的强度降低,抛石和淤泥之间的平衡被打破,抛石向淤泥内滑移和下沉,直至达到新的平衡;第3步是补填后再次进行爆破,并依次循环;第4步是每50m进行一次侧爆。通过改变淤泥强度的方式来代替爆破作用,利用有限元数值模拟方法对这4个过程进行了模拟,在此基础上进行了挤淤效果的预测。通过工程实例,进行了理论预测与钻探、探地雷达实际检测结果的对比,证实数值模拟的结果是正确的。模拟结果表明经过抛石爆破挤淤4个步骤的处理,抛石最终会形成稳定的马蹄形海堤。

The main process of explosion replacement can be divided into four steps. The first step is squeezing soft clay with stone. The second step is conducting explosion in the soft clay, reducing the strength of the soft clay, breaking the balance between the stone and the soft clay, then the stone sliding into the soft clay until the new balance is created. The third step is continuing conducting explosion after adding more stones and repeating the process. The fourth step is conducting side explosion after 50 m-long dike have been constructed. The finite element simulations to the four processes of explosion replacement were conducted respectively through changing the strength of the soft clay instead of the effect of explosion, then the treatment effect can be predicted. The simulations were verified by the actual boring inspecting and ground penetrating radar inspecting results in an engineering application. The simulating results indicate that the sea dike constructed by explosion replacement will be shaped like a horseshoe after the four steps treatment.