Foundation pit pouring thickness detection device

The utility model relates to a foundation pit pouring thickness detection device which comprises a fixed seat, a fixed block is fixedly arranged at the top end of the fixed seat, a movable rod is arranged in the fixed block, a protruding block is fixedly arranged on the inner wall of the fixed block, a limiting groove is formed in the top end of the movable rod, a sliding groove is formed in the fixed block, and the movable rod is arranged in the sliding groove. A sliding groove is formed in the outer wall of the movable rod, a sliding rod is arranged in the sliding groove, one end, located in the sliding groove, of the sliding rod is fixedly connected with a first spring, a clamping groove is formed in the position, located at one end of the sliding rod, of the outer wall of the movable rod, one end of the movable rod is fixedly connected with a fixing ring, and a measuring rod is arranged in the fixing ring. Through cooperative use of parts such as a fixed block, a movable rod, a convex block, a limiting gr