Supporting structure of foundation pit

The invention discloses a supporting structure of a foundation pit. The supporting structure comprises jet grouting piles and a double-row pile structure which is inserted in the jet grouting piles, wherein the jet grouting piles are high-strength cement-soil pile bodies formed on a soil body around the foundation pit, and the multiple jet grouting piles are in mutual lap joint to form a reinforcing region; the double-row pile structure comprises a first row of cast-in-place piles, a second row of cast-in-place piles and connecting beams, the connecting beams are connected with the tops of the first row of cast-in-place piles and the tops of the second row of cast-in-place piles, and the first row of cast-in-place piles, the second row of cast-in-place piles and the connecting beams are all of a reinforced concrete structure. According to the scheme, the supporting structure aims to brace the deep foundation pit under the complicated geological condition with rich water and soft soil and under the condition t