天津体育中心射击馆双向弦支梁结构分析与设计

Analysis and design on bidirectional beam string structure of Tianjin Sports Center Shooting Gymnasium

主要介绍天津体育中心射击馆屋盖钢结构弦支梁的设计过程,重点阐述了三号屋盖双向弦支梁的设计和分析,包括双向弦支梁的体系介绍及参数分析与选择、屋盖自振特性分析、地震作用下结构强度验算以及节点设计等。分析得到双向弦支梁设计应在参数分析的基础上进行详细对比,综合考虑撑杆布置、垂跨比、预拉力、面外拉索等影响因素;对于直线形双向弦支梁,垂跨比在一定范围内时,钢梁最大应力、最大竖向挠度及支座水平位移均随垂跨比的增大而减小;钢梁最大应力及最大竖向挠度随预拉力的增大线性减小,支座水平位移则相反;同时直线形弦支梁的撑杆下节点应具有可靠的面外约束。

The design of beam string structure for steel roof structure of Tianjin Sports Center Shooting Gymnasium was introduced,and the bidirectional beam string( BBS) structure of No. 3 roof were the focuses,including structural system introduction,parametric analysis and selection,natural vibration characteristics,structural strength calculation under seismic action and joint design. The results show that the design of BBS should be compared in detail base on parametric analyses,while effect factors such as strut layout,sag-span ratio,pre-stress degree and out-of-plane cable should be overall considered.With regard to straight line BBS,the maximum stress,maximum vertical deflection and support horizontal displacement of the beam string decrease with the increase of sag-span ratio when the sag-span ratio within a certain range. The maximum stress and maximum vertical deflection of beam string decrease with the increase of pre-stress degree,while support horizontal displacement increases. The strut bottom node of straight line BBS should have reliable out-of-plane support.