Visual Simulation Analysis On Multistage Construction Process Of Space Grid Structure

Reasonable construction method and scientific analysis is an important way that ensure a structure safe and economic. Space structure, with its many advantages, such as reasonable stress, light weight, low manufacturing cost, various form etc., has been widespread used in the scope of the world. Meanwhile, as the structure form getting complicated and the span getting large, it also puts forward more and more requests to the construction techniques. The construction process of space structure is dynamic with continuous change of the shape and stress, thus the most dangerous state of the structure usually appears during the process. Because the traditional design method aims at the design stage, taking no account of the construction influence, it is difficult to reflect this real stress feature of the structure. Yet it is rather difficult to take whole range analysis of the structure during the construction process, for the factors affect the behavior of the structure during the process are many and associated. Currently, theoretical studies on construction analysis are still insufficient and unsystematized.The article expounds several common used construction methods and their features, as well as the many aspects of visual simulation on engineering structure, such as its contents, conditions, technological process, modeling and numerical methods. On foundation of the summary for present theories on construction analysis, the article puts forward a new practical method according to the multistage construction process analysis theory, that is element cumulation method. Based on this method and adopts object-oriented programming technique, an emulator program module for construction process analysis of space structure is developed on the platform of MSTCAD. In virtue of the MFC application program frame and OpenGL graphic development environment, the program creats friendly operation interface and 3D display space. The module, which is able to carry a tracking analysis duiring the whole construction process of space structure in a visualized and dynamic way, has agood practical value because it may provide basis for design and construction.Besides, some critical problems involved in the construction process of steel structure hoisting are studied systematically in the article. In order to change the situation that engineers and technicians have to look up the manual books of lifting performance while choosing cranes, two program modules have been built after studying the features of three classes of cranes which are frequent used. The two modules, one is to build a database for lifting performance data and the other calculate the ability of the cranes, will provide great conveniences for users.