Construction method of anti-seepage joint structure suitable for deep and thick covering layer foundation and large deformation

The invention discloses a construction method of an anti-seepage joint structure suitable for a deep and thick covering layer foundation and large deformation. The construction method comprises the steps that S1, a deep and thick covering layer is excavated to a first elevation; s2, a reinforced concrete slotted hole guide wall is constructed; s3, continuously excavating to form slotted holes; s4, the reinforcement cage and the embedded grouting steel pipe are fixed in the slotted hole; s5, the slotted holes are poured to the designed elevation, a first concrete anti-seepage wall is formed, and pile heads are hit off; s6, fixing the rubber waterstop; s7, a water stop copper sheet is fixed and cast in place to the designed elevation, and a second concrete anti-seepage wall is formed; s8, monitoring and tracking, and performing grouting treatment; s9, the SR plastic filler is placed; and S10, gravel is laid, concrete dam bottom layer steel bars are bound, and a concrete gravity dam is poured. According to the c