矩形顶管考虑泥浆触变特性的顶推力计算

矩形顶管施工顶推力的计算是施工中非常重要的环节,主顶油缸在设计顶力时需要依据公式计算结果进行配置,因此,公式计算结果的准确性往往关系到施工的财力物力成本。顶推力主要由顶管掌子面的迎面阻力和管壁周围的摩阻力两部分组成,迎面阻力可以被认为是一个定值,因此顶推力公式计算的关键是管周摩阻力的推导。考虑管土之间的泥浆触变特性,通过黏性流体力学的N-S方程结合微元分析法计算矩形顶管管壁周围的摩阻力,并以此推导出顶推力计算公式。通过工程验证,推导的公式结果误差为21%,与现有矩形顶管顶力计算公式对比,更接近实际测量值,验证了本文公式在矩形顶管顶推力计算方面的准确性。

Calculation of Jacking Force of Rectangular Pipe Jacking Considering Thixotropy of Mud

Calculation of jacking force in rectangular pipe jacking construction is very important in construction. When designing the jacking force of the main roof cylinder, it needs to be configured according to the formula calculation result, so the accuracy of the formula calculation result is often related to the financial and material cost of construction. The jacking force is mainly composed of the face resistance of the pipe jacking face and the friction resistance around the pipe wall. The face resistance can be regarded as a constant value, and thus the key to the calculation of the jacking force formula is the derivation of the friction resistance around the tube. The thixotropic properties of mud between pipe and soil are considered, the friction resistance around the wall of rectangular pipe jacking is calculated by using the N-S equation of viscous fluid mechanics combined with the element analysis method. Based on this, the calculation formula of jacking force is deduced. The error of the derived formula is 21% through engineering verification. Compared with the existing formulas for calculating the jacking force of rectangular pipe jacking, it is closer to the actual measured value. The accuracy of the formula in calculating the thrust force of rectangular pipe jacking is verified.