M-shaped roof truss and mounting method thereof

The invention discloses an M-shaped roof truss. The M-shaped roof truss comprises a plane truss, a U-shaped bracket and a space truss which are arranged sequentially in the left-right direction; the U-shaped bracket comprises multi-truss U-shaped pipes arranged sequentially in the front-back direction; the lower end part of the plane truss is fixed on a fixed building, and the upper end part of the plane truss extends to the upper right of the lower end part of the plane truss; the lower end part of the space truss is fixed on an adjacent building, and the upper end part of the space truss extends to the upper left of the lower end part of the space truss; the left end part of each U-shaped pipe is fixedly connected with the upper end part of the plane truss, the right end part of the U-shaped pipe is fixedly connected with the upper end part of the space truss; the plane truss and the space truss are inclined; the U-shaped bracket is connected between the plane truss and the space truss, so that large span of the roof truss is guaranteed; the plane truss is connected to the side where the building with smaller settlement ratio is located, the space truss is connected to the side where the other building with larger settlement ratio is located, and stable structure of the M-shaped roof truss is guaranteed. The invention further discloses a mounting method of the M-shaped roof truss.