Study On Traveling Wave Effect Of Super-long Span Giant Mesh-prestressed Coal Shed Roof Structure

As a large warehouse for coal storage,the dry coal shed needs Super-large-span space to meet the requirements of storage and operation space.When the design of dry coal shed structure exceeds a certain span(200m),the conventional structure of dry coal shed has shortcomings such as insufficient bearing capacity,poor stability and poor seismic performance.Therefore,reasonable selection of super-long-span space dry coal shed structure has become an important factor affecting its development.Seismic action has complex response.When the span of the structure is very large(more than 200 m),the amplitude and phase of the seismic wave reaching the ground support point through different paths will change,and the influence of traveling wave effect on the structure can not be ignored.Once the super-long-span dry coal shed structure collapses,it will bring huge economic losses and seriously threaten human lives.Therefore,it is of great significance to study the traveling wave effect of the new structure of the super-long-span space dry coal shed.Comparing the advantages and disadvantages of the new type of super-long-span space structure,a super-long-span gigantic grid-prestressed coal shed roof structure is put forward,and the parameters such as the rise-span ratio and initial prestress which make the structure stronger,more stable and economical are determined.The finite element model of super-long-span gigantic grid-prestressed structure is established by ANSYS software.Specific work includes the following aspects: defining the selection factors of super-long-span spatial steel structure,and designing super-long-span spatial steel structure with span of 300 m based on scheme comparison method and structural optimization method,a super-long-span mega-grid-prestress structure is proposed,comparing the structure with the cylindrical mega-grid structure,it is proved that the super-long-span mega-grid-prestress structure type is super-long-span mega-grid-prestress structure.Superiority.Analysis and reasonable selection of parameters such as rise-span ratio,mesh size and initial prestress of Super-large-span mega-grid-prestress structure.Establishment of Super-large-span mega-grid-prestress structure model by using finite element software ANSYS.Optimizing the cross-section area of members of the structure by using the criterion of full stress,aiming at minimizing steel quantity and controlling strength stability conditions.Finally,an economical,reliable,high strength and high stability super-long-span space steel structure is designed,which provides a basis for the design of super-long-span space steel structure.By changing the apparent wave velocity,structure position and mesh size,the traveling wave effect of super-long-span mega-grid-prestressing structure is studied concretely.The rule that the structure is affected by the traveling wave effect is obtained,and the most disadvantageous position of the structure affected by the traveling wave effect is found out.It provides a basis for the selection of mesh size when considering the traveling wave effect in the actual design of super-long-span mega-grid-prestressing structure.By comparing and analyzing the influence factors of traveling wave effect with the 290 m span steel tube arch structure designed by Wang Fangli,it is proved that the Super-large-span mega-grid-prestressing structure has certain advantages in resisting the traveling wave effect.The research results show that considering multi-point and multi-dimensional seismic wave input is more in line with the actual situation;in most cases,when the apparent wave velocity decreases,the influence of traveling wave effect on the internal force of the structure becomes more obvious,and the deflection basically increases.the large transverse grid of the structure is more affected by traveling wave effect,while the longitudinal one is less affected by traveling wave effect.and the design of super-long-span mega-grid-prestressing structure is more effective.The smaller mesh size should be used in the reasonable mesh size selection,which provides a basis for the selection of mesh size when the traveling wave effect is taken into account in the actual design of structures.This paper has 36 figures,24 tables and 53 references.