River channel structure of underpass tunnel

The river channel structure comprises an open channel, a grit chamber, a closed conduit inverted siphon well and an underpass section closed conduit, the upstream and downstream of the underpass section closed conduit are sequentially communicated with the closed conduit inverted siphon well and the grit chamber respectively, the grit chamber is communicated with the open channel, the elevation of the bottom of the grit chamber is lower than that of the bottom of the open channel, one side of the closed conduit inverted siphon well is communicated with the grit chamber, and the other side of the closed conduit inverted siphon well is communicated with the open channel. A middle partition wall and a bulkhead gate are arranged in the middle of the closed conduit inverted siphon well, a drain grating is further arranged at the communication position of the closed conduit inverted siphon well and the grit chamber, and the other side is communicated with the underpass section closed conduit. According to the utili