The steel truss is assembled on the assembly platform. After the assembly, the assembled steel truss beam is lifted to the installation position by 25t truck crane. In order to ensure the normal operation of hoisting construction, the site of 25t truck crane traveling route needs leveling and hardening treatment, and the hardening treatment range is 7m * 198m.

         After the truss hoisting is completed, the steel purlins will enter the site and be stacked and assembled according to the layout plan after acceptance.There are a large number of purlins installed with many types. A dedicated technician is responsible for material distribution on the ground. After the installation of purlins, the technical director shall check the orientation of purlins, whether the bolts are fastened, and whether the installation straight line and deflection of purlins meet the design requirements.

         Purlin section is small and light, so it can be hoisted by one hook and multiple hoisting or piece by piece.The correction of purlin is mainly the spacing size and its own straightness.The sample bar for spacing inspection shall move back and forth along the purlin members. If there is any error, loosen or tighten the purlin tie rod bolt for correction.Straightness shall be checked and corrected with stay wire and steel ruler, and finally fixed with bolts.

When the hoisting of steel structure grid structure is carried out at high altitude, the operators are faced with all kinds of great risks when walking or operating on the steel structure beam or beam. Personal falling is the biggest risk and the consequence is the most serious.In order to ensure the personal safety of high-altitude workers, a series of steel wire mesh lines are temporarily installed on the high-altitude working surface of steel structure buildings in the construction process. The temporary installation of steel wire ropes is called “lifeline”.When the operator works at high altitude, the safety rope that he wears is buckled on the life line. In case of the operator falling, his body can still be suspended on the life line, so as not to fall to the ground and cause safety accidents.Lifeline must have the following characteristics:

         It is safe and reliable, and sufficient strength and stability must be ensured, so as to withstand the impact of personal falling on lifeline.

         It is convenient and feasible. The completed lifeline must not affect each operation process of the project, and the operators can use it conveniently in the operation process.

         It is easy to install and dismantle. It is not suitable to spend too much manpower and material resources for the installation and removal of lifeline, so as to avoid affecting the schedule and cost of the project.

In theory, steel structure engineering is divided into single-layer, multi-layer, high-rise, grid structure, profiled metal plate, etc.The construction unit of steel structure engineering shall have the engineering construction qualification, and shall have the construction organization design, construction scheme and other technical documents approved by the project technical director, which is similar to the civil construction.

         The installation inspection of steel structure grid structure engineering shall be carried out on the basis of acceptance and acceptance of sub projects such as welding connection and fastener connection.On the basis of the construction procedure, the welding procedure should be measured before the installation, or the negative temperature should be measured.