Combined frame type isolation protection system and construction method thereof

The invention discloses a combined frame type isolation protection system and a construction method thereof. The system comprises prefabricated piles longitudinally arranged in lines at intervals and transversely arranged in rows at intervals along an expected dig tunnel, wherein pressing block installation grooves are vertically formed in the outer surfaces of all the prefabricated piles; pressing blocks are movably arranged in the pressing block installation grooves; and tension mechanisms for connecting and tensioning the prefabricated piles are arranged between the lower half sections of every two adjacent prefabricated piles. The system has the following beneficial effects: two rows and multiple lines of prefabricated pile cross bars and the tension mechanisms are used for forming the isolation protection system to replace a traditional box culvert; the system is simple in structure, high in construction efficiency, reasonable in stress state of all parts and lower in disturbance of surrounding buildings; two prefabricated piles are connected through steel wire cables in the tension mechanisms, and the positions of the steel wire cables between the two prefabricated piles are grouted to form soil cross beams at intervals to achieve a support effect on the isolation protection system; and the pressing blocks are arranged to realize the step-by-step implementation of pressing the pressing blocks and pressing the piles.