| Hyperbolic paraboloidal(H.P.) shell has some own virtue such as graceful curved surface, easy to support formwork, inexpensive cost. H.P. shell can be seen as surface action system. Arch mechanism and append mechanism are working together, and they restrict each other, so the structure can work high efficiency, which superiority than other kind of shell. While H.P. combined shell has mentioned above advantage, and can design longer span and space. Therefore, it is appropriate to utilize H.P. combined shell when economical consideration more than architecture aesthetics request.Theory analysis, structure design, structure construction and its project application of H.P. concrete combined torsion shell with parallelogram bottom surface projection were discussed in this paper, which make us grasp the basic performance, methods of structure design and construction of H.P. combined torsion shell, so the reference was offered for a similar project application in the future.In the structure design of the H.P. combined torsion shell, keypoints were pointed out. In the optimization analysis, the method of structure optimization analysis of long-span H.P. concrete combined torsion shell roof with parallelogram bottom surface projection was particularly expatiated. During the structure design, analysis of wind load, seismic effect, and structure bulking stability were done. Weight and rise-span ratio optimization were analyzed by numerical simulation technology and self-design programme, and obtained the distribution of optimizational rise-span ratio and corresponding gentle degree. The reasonable elements and analysis method were adopted, and essentials were pointed out about structure design, which guide the similar project in the future. The optimization analysis shows that Weight optimization made the weight less 19.8 percent and the cable-arch mechanism play better role when the distribution range of rise-span ratio is from 0.15 to 0.2 through the keypoint such as most displacement of structure, glide seat displacement, horizontal force of shell roof and stress distribution. The result of optimization analysis of this paper can provide better preference for the similar structure design.construction include key construction technology of spatial exact precision location, design and installation of high scaffold, concrete cast, prestressed construction, vacuum aided grouting, supprot system removal, construction measurement and so on. The construction model test of shell roof was made before construction. The practise show that the safty of shell structure is better,meanwhile construction quality and the operation after completion is well.Considering the complicated dimensional curve surface of H.P. combined torsion shell with parallelogram bottom surface projection, traditional measurements cannot rapidly and accurately complete the spatial measurement location. In this paper, the simplified method was adopted, which made spatial accurate measurement location to H.P. concrete combined torsion shell of Huanan Technology university in Guangzhou university city. First of all, using straight line characteristics, plane measurement location was carried through, which the dimensional points were projected into plane, and then to find the rule of the third dimension and realized the accurate spatial measurement location, meanwhile, controlling points were confirmed by using keypoints in shell corner and avoid system error. The problem of spatial coordinate accurate measurement location of combined shell was solved, which establish well basis for the formwork supporting and subsequent construction, and assure the smoothness of spatial curve surface.Long-span prestress reinforced concrete H.P. combined torsion shell with parallelogram bottom surface projection has vivid and beautyful style, which have two direction straight line, so the formwork supporting and steel bar construction was very convenient. Because using modern pre-stressed technology, the span and thichness are all get high level and make proper internal force distribution and construction sequence by prestressing on the shell roof, meanwhile ensure the safty of shell roof.After finished cast concrete of shell roof, different formwork removal methods have much influence on shell because of its inadequate strengthen. For the sake of safty during construction period, the dissertation use FEM program to optimize formwork removal sequence of H.P. combined shell roof with parallelogram bottom surface projection for the example of Huanan Technology University Gymnasium in Guangzhou university city. The main tension stress controll as its standard, and then determine the proper sequence of formwork removal. Several method of formwork removal were considered, by comparsion, the way of annular segmentation is proper for formwork removal. the variation most tension stress and displacement were obtained through the computaion and measurement, and obtained internal force distribution of different sequence, furthermore got optimal formwork removal sequence, and providing basis of theory for construction, and then making for guiding similar project construction.
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