摘要
包银铁路乌海黄河特大桥主桥为(80+80+260+80+80)m钢-混混合梁斜拉桥,桥位处于Ⅷ度震区。为确定受力合理、造价经济的桥塔造型,结合抗震需求,对H形塔、门形塔、井形塔及上塔柱内收的井形塔4种桥塔造型方案进行结构内力与经济性对比分析,最终选择兼顾受力、经济和美观的H形塔方案。H形桥塔采用混凝土结构,塔高101 m,其上、中塔柱及上横梁采用单箱单室截面,下塔柱及下横梁采用单箱双室截面,桥塔横桥向宽24.5 m,桥面以上有效塔高73.5 m,高跨比为0.283;索塔采用环向预应力锚固,环向预应力采用缓粘结预应力钢绞线、井字形布置。对H形桥塔进行施工、运营阶段及地震工况下的计算分析,结果表明:桥塔结构强度、抗裂性、稳定性及抗震性能均满足规范要求。
The main bridge of Wuhai Huanghe River Bridge on Baotou-Yinchuan Railway is a steel and concrete hybrid girder cable-stayed bridge,having a main span of 260 m and four side spans of 80 m.The bridge is located in an 8-degree high-intensity seismic region.To determine the pylon configuration that would lead to reasonable load bearing behavior and economic value and meet the seismic protection demands,four pylon schemes including H-shaped pylon,portal pylon,#-shaped pylon and#-shaped pylon with smaller upper column spacing were compared,and the H-shaped pylon was finally selected out of the balance of force,economy and aesthetic effect.The H-shaped pylon is a concrete structure rising 101 m.The upper pylon columns and upper cross beams are of single-cell box cross-section,while the lower pylon columns and lower cross beams have two-cell box cross-sections.The pylon measures 24.5 m along the bridge width and 73.5 m high above the deck,resulting in a pylon height to span ratio of 0.283.The cables are anchored to the pylons via loop prestressing tendons that are the retard-bonded prestressing tendons arranged in the#-shape manner.The calculations of the H-shaped pylons in construction and service stages as well as during seismic events show that the strength,anti-cracking ability,stability and anti-seismic performance of the pylon structure can meet the code requirements.
作者
牟兆祥
李恩良
杜宝军
MU Zhao-xiang;LI En-liang;DU Bao-jun(China Railway Design Corporation, Tianjin 300308, China)
出处
《桥梁建设》
EI
CSCD
北大核心
2021年第3期108-115,共8页
Bridge Construction
基金
中国铁路设计集团有限公司科技开发课题(7218126)。
关键词
铁路桥
斜拉桥
桥塔
高烈度震区
抗震计算
方案比选
结构设计
railway bridge
cable-stayed bridge
pylon
high-intensity seismic region
seismic calculation
scheme comparison
structural design
