土方车作用下基坑栈桥双向板等效荷载研究

Study on Equivalent Load for Earthwork Truck on Two Way Slab of Trestle Bridge of Foundation Pit

深大基坑常需设置栈桥以便于土方开挖与外运,但目前对于栈桥计算荷载取值比较随意,而且现行《建筑结构荷载规范》仅提供300kN的消防车作用下楼板的等效荷载,与常规基坑土方运输车辆规格相差较大。文章分别分析了在《公路桥涵设计通用规范》中所采用的车辆荷载和华威驰乐牌SGZ3312GE型自卸汽车荷载作用下,考虑土方车最不利布置,使用大型有限元软件Ansys确定其等效均布荷载取值,并提出其它类似车辆等效荷载取值方法,为基坑栈桥设计提供了数据支撑。

Trestle is often set up in deep and large foundation pit to facilitate earthwork excavation and transportation,but at present,the calculated load value of trestle is relatively random,and the current"code for load of building structures"only provides the equivalent load of floor under the action of 300kN fire truck,which is quite different from the current specifications of conventional foundation pit earthwork transportation vehicles.In this paper,the vehicle load used in"general code for design of highway bridges and culverts"and the load of SGZ3312GE dump truck are analyzed respectively.Considering the most unfavorable layout of earthwork truck,the equivalent uniform load value is determined by using large-scale finite element software ANSYS.And other similar vehicle equivalent load value method is proposed,which provides data support for the design of foundation pit trestle.