Main battalion: bridge stretchers, water-control belts, water stoppages, seals, foam sheeting, rubber inflatable core models, supporting steel plates, pre-burials of bridges, beam-bed steel plates, anti-shock limit blocks, guard railings, grid-mounted steel bars, pre-resilient anchors, beads, bellows, discharge pipes, acoustic tubes, protection nets, earthworks, earthworks, membranes, waterproofing materials; installation, maintenance and replacement of bridges, stretching units; waterproofing of bridge tunnels。