The utility model discloses a flexible protective device for treating a
collapsed cavity at the top of a tunnel, which comprises at least two flexible protective nets which are arranged from top to bottom and connected to the inner wall of the
collapsed cavity, and the aperture of the lower part of each flexible protective net is smaller than that of the upper part of each flexible protective net. The protective net is composed of a steel
wire rope protective net body and a twisted-pair hexagonal flexible net body, the steel
wire rope protective net body is formed by rhombic weaving of Galfan
coating steel wire ropes, and the twisted-pair hexagonal flexible net body is formed by weaving of A-grade Galfan
coating steel wires, overlaps the edge of the steel
wire rope protective net body by 10-20 cm and is tied. The steel wire
rope protective net is formed by splicing meshes of different specifications, splicing follows a specific principle, and steel wire
rope buckles are used for connection. The device is further provided with anchor rods, spring hooks and other components, and the number and size of the components are determined according to the three-dimensional data of the
collapsed cavity. Compared with a traditional protective net, the device can effectively absorb
rockfall energy, is good in buffering effect, high in adaptability to different collapse cavities, easy and convenient to install and capable of reducing construction risks and guaranteeing
tunnel construction and
operation safety.