【正文】 sssection to the main welded joints before installation test of the welding process, set the welding the grid material and various parameters. Between the beam and the beam, the connection between the beams and columns, you can take the accuracy of the welded connections or highstrength bolts, pay attention to the highstrength bolts connecting holes. System hole, there are two, one is a high precision CNC drilling, another is relatively low precision template system holes. Technical conditions allow more suitable for multiaxis CNC drilling. Transported to the site to test the bolts parameters, installation can not be forced to tighten with a wrench into or forcibly break into with a hammer, step screwed into the screw to go through the beginning, retighten and the final twist. 、 The steel ponents stacked and select installation of mechanical Location Typically the case of the land area of the mounting structure for the structure covers an area of times. Transported to the site from the transit yard supporting steel members in accordance with the order of the installed water handling machinery placed on the installation of machinery within the radius of gyration. Because of transportation reasons caused by the deformation of the ponent, at the construction site should be corrected. General installation of steel structures used tower cranes, the length of the arm to have enough coverage, and lifting capacity accordingly enough to meet the lifting requirements of various parts of the ponent. Wire rope capacity must be able to meet the the lifting height requirements。 附件 2：外文原文 Research and application of steel structures in civil engineering Civil engineering structures used to the two materials, . reinforced concrete and structural steel, for civil engineering, not only from the structural characteristics of the viewpoint, but also consider the costeffectiveness of construction and the construction of validity. This article analyzes the characteristics of steel structures in civil engineering, and briefly discusses the steel structure construction points. Civil engineering steel structure characteristics 、 Strength Generally, the structural member the ability to withstand or acmodate the effect of action by the strength of the material determined. Can make use of the relevant national standards to determine the performance of the structural steel member, and these standards are listed in the material of the steel structure can be used, such as building the structural steel to meet the the CSA standard ASTM standardA992/A992M or CAN / CSA , construction steel has undergone great changes, the past building structure with tensile strength and yield strength data were drawn from the history of CISC (2020), and Canada for structural steel engineering and building structural steel standard set of seven steel grades and 8 intensity level. According to the yield strength range of 260 to 700 MPa. But not all kinds of steel have all the intensity level, so if a particular building steel structure design, choice of steel types and intensity level is very important. Whole steel structure can reduce material consumption, reduce structural weight, lower support member and the size of the foundation, and ultimately reduce the cost of the entire structure of the building. 、 Stiffness The suitability parameters of the stiffness of the vibration, deformation, etc. is determined by the stiffness of the member, and thus is determined by the stiffness of the str