解决砂卵石地层盾构隧道同步注浆过程中浆液扩散模式及地层响应机制认识不足的问题，采用计算流体动力学-离散元（CFD-DEM）耦合方法建立6孔注浆数值模型，系统分析注浆孔布置模式（Ⅰ型： 拱腰加强型； Ⅱ型： 顶底加强型）、注浆流量（5×10-5~1.25×10-4 m3/s）和注浆率（100%~250%）对注浆效果的影响。结果表明： 1）地表沉降随注浆流量增大而减小，随注浆率提高而增大。Ⅱ型模式地表沉降整体大于Ⅰ型； 低注浆流量（5×10-5 m3/s）下注浆孔布置模式对地表沉降影响显著，该影响随注浆流量增大逐渐减弱。2）浆液以注浆孔为中心向周围土体渗透扩散，呈半圆形扩散形态。当Ⅱ型模式注浆率为200%时，注浆流量由5×10-5 m3/s提高至1.25×10-4 m3/s，拱顶径向扩散距离从52.7 mm增大至88.8 mm，增幅达68.5%。高注浆流量促进径向扩散，低注浆流量有利于环向交汇。3）盾尾空隙覆盖率与浆液损失率均随注浆率提高而增加。综合考虑填充效果与经济性，建议注浆率低于150%时采用Ⅰ型注浆孔布置模式，注浆率高于200%时采用Ⅱ型模式。注浆流量的变化对盾尾空隙覆盖率和浆液损失率的影响无明显规律。
To investigate the grout diffusion patterns and response mechanisms during synchronous grouting for shield tunneling in sandy cobble strata, a coupled computational fluid dynamics-discrete element method model is employed to establish a numerical model of six-hole grouting. The effects of grouting-hole configuration (Type Ⅰ: arch-waist reinforced; Type Ⅱ: top-bottom reinforced), grouting flow rate (5×10－5－1.25×10－4 m3/s), and grout-volume ratio (100%－250%) on grouting performance are systematically analyzed. The results demonstrate that surface settlement decreases with increasing grouting flow rate but increases with increasing grout-volume ratio. The Type Ⅱ configuration generally results in greater surface settlement than the Type Ⅰ configuration. At a low grouting flow rate (5 × 10－5 m3/s), the grouting-hole configuration significantly affects surface settlement. However, this influence gradually diminishes as the grouting flow rate increases. Furthermore, the grout permeates and diffuses from the grouting holes into the surrounding soil, forming a semicircular diffusion zone. For the Type Ⅱ configuration and a grout-volume ratio of 200%, increasing the grouting flow rate from 5 × 10－5 to 1.25 × 10－4 m3/s results in a 68.5% increase in the radial diffusion distance at the tunnel crown from 52.7 to 88.8 mm. High grouting flow rates promote radial diffusion, whereas low flow rates favor circumferential convergence. Both the grout cover ratio and grout loss ratio increase with increasing grout-volume ratio. Considering filling effectiveness and cost-efficiency, the Type Ⅰ configuration is recommended for grout-volume ratios below 150%, whereas the Type Ⅱ configuration is more suitable for ratios above 200%. Variations in grouting flow rate do not significantly influence the grout cover ratio and grout loss ratio.
