注浆是一种有效的地基加固及防渗处理技术，浆液扩散范围预测则是注浆技术的重点和难点之一，而层状岩体由于物理力学性质的各向异性使得浆液的扩散更加复杂。新维矿3条斜井均近距离下穿镇舟河底部，斜井顶板至河床强风化层最近距离仅约10 m，为消除施工过程中的涌水威胁，采用了超前预注浆防渗技术，掘进工作面循环作业，钻爆法开挖，超前支护，现浇钢筋砼拱，再进行防水处理;其次，结合现场近水平分布砂泥岩互层特征，并考虑浆液黏度的时变性，建立了砂泥岩互层时变性注浆模型，并对不同工况下的注浆扩散范围进行了模拟;结合模拟结果与现场条件，选用水泥单液浆为主，水泥-水玻璃双液浆作为补充材料，在掘进工作面布置注浆孔16个，注浆压力6 MPa，采用分段下行式注浆，每个预注浆循环的长30 m，从后往前一段一段地钻注至终深，单个注浆段长5 m，反复注浆，反复扫孔。注浆时利用P-q-t曲线对单孔注浆效果进行检验，以注浆压力达到预设值且注浆流量持续减小作为停注条件;此外钻孔取心试验发现浆液与裂隙岩体形成了渗透率较低而强度较高的结石体，且浆液在水平方向的扩散明显占优，远大于垂直方向的渗透距离，浆液扩散范围近似呈椭球形分布。此外，通过注浆前后围岩渗透性对比发现，注浆后按巴布金公式得到的渗透系数在3 mm/d左右，与注浆前压水试验得到的岩体渗透系数(0.239和0.204 m/d)相比降低了近2个数量级。实践表明，该超前预注浆技术及时变性注浆扩散模型在砂泥岩地层防渗中得到成功应用，保障了河流下矿井安全高效施工。

Grouting is an effective foundation reinforcement and anti-seepage treatment technology. The prediction of slurry diffusion range is one of the key points and difficulties of grouting technology. Due to the anisotropy of the physical and mechanical properties of the layered rock mass,the diffusion of the slurry is more complicated. Three inclined shafts of Xinwei Mine pass through the bottom of Zhenzhou River. The nearest distance from the inclined shaft to the strong weathered layer of the riverbed is only about 10 m. In order to eliminate the threat of water inrush during construction,an advanced pre-grouting anti-seepage technology was adopted. The excavation working face adopted a cyclic operation,excavation by drilling and blasting method,advanced support,cast-in-place reinforced concrete arch,and then waterproof treatment. Considering the near-horizontal distribution of sand-shale interbeds and the time-varying viscosity of the slurry,a denatured grouting model for sand-shale interbeds was established,and the grouting diffusion range under different working conditions was simulated. Referring to the simulation results and on-site conditions,the cement single-liquid slurry was mainly used,and the cement-water glass double-liquid slurry was used as the supplementary material. 16 grouting holes were arranged on the excavation face,and the grouting pressure was 6 MPa,and the segmented grouting was adopted. The length of a pre-grouting cycle was 30 m,the drilling and grouting were from the back to the front,then to the final depth,the length of a single grouting section was 5 m with repeated grouting,and repeated drilling. When grouting,the P-q-t curve was used to test the single-hole grouting effect,and the grouting pressure reached the preset value and the grouting flow rate continued to decrease as the stopping condition. In addition,the borehole coring test found that the slurry formed a stone with the fractured rock mass,which has a low permeability and high strength. Moreover,the diffusion of the slurry in the horizontal direction was obviously superior,far greater than the penetration distance in the vertical direction,and the slurry diffusion range was approximately ellipsoidal. In addition,by comparing the permeability of the surrounding rock before and after grouting,it was found that the permeability coefficient obtained by the Babkin formula after grouting was about 3 mm / d,compared with the rock mass permeability coefficient obtained by the water pressure test before grouting (0. 239 m / d and 0. 204 m / d). The permeability coefficient reduced by nearly two orders of magnitude. The practice shows that the advanced pre-grouting technology and the time-varying grouting diffusion model have been successfully applied in the anti-seepage of sand-shale interbed,which ensures the safe and efficient construction of the mines under the river.