泥水盾构环流系统是将开挖下的石碴从掘进界面输送出来的核心系统，石碴在环流管道内的流动特性是决定石碴能否顺利输送的关键。论文基于计算流体力学和离散单元法建立泥水盾构环流系统水平直管内石碴运动模型，研究石碴形状系数、等容粒径和数量对石碴起动速度的影响。仿真研究结果表明： 在石碴等容粒径相等情况下，不同形状的石碴起动速度大小顺序为： 椭球体>扁平状>近球形；当石碴等容粒径为38.5、42.5、53.3、56.2、58 mm时，石碴起动速度分别为0.48、1.06、1.26、2.36、4.7 m/s，随等容粒径的增大呈指数增大；随数量的增多呈对数增长，多颗粒起动速度随数量的增多增幅较为平缓，最大增幅为21%。

The circulating system of slurry shield is the core system used to transfer the excavated pebbles from the tunneling face. The flow characteristics of pebbles in the circulation pipeline are the keys to smooth transportation of the pebbles. The simulated motion model in the horizontal straight pipe of the slurry shield circulation system is established based on computational fluid dynamics and discrete element method; and the influence of shape factor, the equal volume particle size and pebble number on the pickup velocity of pebbles are studied. The simulation results show that: （1)When the equal volume particle sizes of the pebbles are the same, the pickup velocity of pebbles with ellipsoid shape is the largest, followed by that with flat shape and that with nearspherical shape is the smallest. （2）The pickup velocity of the pebble exponentially increases with the equal volume particle size of pebble increase. （3）The pickup velocity of pebble logarithmically increases with the pebble number increase; while the pickup velocity of multi particles gently increases with the pebble number increase, and the maximum increase reaches 21%.