Research And Application Of A New Type Of Large-span Prefabricated Panel-rib Composite Floor Structure

With the green and sustainable development strategy put forward,the construction industry model in China has gradually shifted from traditional to prefabricated buildings.There are many problems with the traditional building structure,such as complex technology,long period and high cost,and hardly to guarantee the headroom and dead weight in longspan structure.To deal with the above problems,this paper combines with Nanchang Wusha hub project management room,puts forward a new type of large-span precast Grid-Plate Ribbed composite floor structure,GPR floor for short.By using the research method of finite element numerical simulation,the static and dynamic performance of the floor is parameterized,the reasonable range of structural parameters is given.The mechanical properties and economic and technical indexes of the traditional primary and secondary steel beam floor are compared and analyzed in the project of Wushahe management building,so as to lay the foundation for the application of the new floor in more practical projects.The main contents and results of the study are as follows:(1)The geometric structure,structural characteristics and research methods of GPR floor are described in detail.The basic assumption and material constitutive relation suitable for the finite element analysis of GPR floor are obtained.(2)A GPR floor with a plane size of 18 m × 18 m is selected as an example,by analyzing the static and dynamic characteristics of the GPR floor,rationality and reliability of this new type of floor structure are checked.The study shows that this new type of floor structure is distributed in bowl shape,which accords with the deformation characteristics of plates.The GPR has reasonable structural stress,higher structural stiffness and good unity,which can meet the requirements of the current code.(3)Parametric analysis is conducted on the GPR floor to explore the primary and secondary parameters affecting the static and dynamic performance of the structure,and a reasonable size range is obtained to provide guidance and suggestions for engineering design.It is recommended that the thickness of the internal concrete slab be 1/15?1/40 of the size of the individual unit,and high span ratio be 1/23?1/30.The size of the independent cell grid is 1/6?1/10 of the span,and the number of grids should not be less than 6.It is suggested to change the form of the element at the support,to avoid advanced destruction due to excessive stress at the support.(4)In the floor design of management room project of Nanchang Wusha river pump gate,the GPR floor is compared with the primary and secondary beam floor with steel frame for comprehensive performance indexes.The research shows that under the same load parameters,the structural rigidity of GPR floor is greater,the seismic and lateral resistance capability is stronger,the dead weight is lighter,0.35 m can be reduced in the height of structure,8.33% reduction in the amount of concrete and steel can be reduced by 7.71%.GPR floor is a new structural system,integrating "high height,open room,safety and environmental protection".