Urban complex environment water diversion port connecting tunnel advance support structure

A forepoling structure for a water diversion port connecting tunnel in an urban complex environment is arranged on the water diversion port connecting tunnel of a water delivery tunnel in a water transfer project, high-pressure jet grouting piles are closely arranged and encircled on the earth surface within the range of 16 m along the axis inlet section of the connecting tunnel in a double-row mode, and meanwhile consolidation grouting drill holes are formed within the range of the high-pressure jet grouting piles for consolidation grouting; secant piles are closely arranged on the two sides of the middle-rear section of the connecting tunnel to form a waterproof curtain; dewatering wells are arranged on the outer sides of the two sides of the middle-rear section of the connecting tunnel and the outer side of the intersection of the conveying tunnel and the connecting tunnel; a vault pipe roof is arranged within the range of 95 degrees of the vault of the connecting tunnel, and meanwhile advance grouting is