When the cantilever push out method is used to build the bridge, rock and roll are preset on both sides, and most components of the bridge are pushed out of the shore rocking wheel Assemble it on the bridge, and then push the bridge forward smoothly and slowly with manual or mechanical traction to the opposite bank. This method is simple and rapid, but it should be noted that before the front end of the bridge reaches the rock on the opposite bank, the center of gravity of the bridge should always be after the rock on the bank, so as to prevent the bridge from overturning in the river. The way to ensure the center of gravity of the bridge after launching the bank rock is to splice several additional trusses at the front end of the main bridge, which is called the guide beam (nose frame). Only truss (single-layer truss), cross beam and wind resistant tie rod are installed on the guide beam, and longitudinal beam and bridge deck are not installed. When the bridge is pushed into place, the guide beam can be removed.
In the process of pushing out the bridge, due to the most deflection caused by the weight of the guide beam itself and the fact that the opposite bank is higher than the pushing out bank, the guide beam is lower than the opposite bank, so it can not be put on. It can be raised slowly and moderately by crane.