新旧规范对预应力连续刚构桥线形影响分析

《公路钢筋混凝土及预应力混凝土桥涵设计规范》2004版在1985版的基础上做了较多修改。结合阿蓬江大桥工程实例,对比分析了两版本规范在抗裂验算要求、徐变计算模式、刚度取值和预拱度计算公式的差别对连续刚构桥线性的影响。结果表明,按照2004版规范设计验算的连续刚构桥,施工预拱度高,成桥下挠度小,桥面线性更加美观、合理。

Deck Layout Influence of Continuous Rigid-frame Bridge between Updated and Old Specification

"Design Specification of Highway Reinforced Concrete and Pre-stressed Concrete Bridges and Culverts"in 2004 edition changed a lot compared with that in 1985 edition. Taking A’Pengjiang Bridge with a (90m+170m+90m) continuous rigid-frame bridge as an example,some influence factors and characters were discussed about deflection of pre- stressed concrete continuous rigid-framed bridge due to different provisions between updated and old specification"Design Specification of Highway Reinforced Concrete and Pre-stressed Concrete Bridges and Culverts"issued in 2004 and 1985 separately. The results show that"2004 specification"modifications included crack resistance,calculation pattern of creep and structural stiffness result in a lower deformation than"1985 specification ". The long term growth factor to camber formula is introduced to camber,which leads to a more beautiful and reasonable deck layout.