Results show that there are solution caverns and submerged current in the bed rock, causing unstability in the bottom of the slot of the cutoff wall, m.

• 分析表明,坝基基岩存在溶洞及洞内潜流,致使防渗墙槽孔孔底失稳、灌浆及堵漏材料大量流失和坝基细砂层液化,导致副坝大规模塌陷。