4215;45m预应力混凝土简支T梁桥设计.doc

本科毕业设计 4×45m 摘要 桥梁是最重要的交通设施之一。本设计为四跨预应力混凝土简支桥梁。桥面净宽9+2×0.75米，桥下净空5米，跨径为45米。本设计分为以下几个部分：（1）桥面板的设计。综合各种因素，本桥采用预应力T型简支梁，预应力T型简支梁具有安装重量轻、跨度大等优点，适用于大中跨度桥梁。桥面采用5片宽度为2.1米，梁高为2.4米，跨度为44.96米的预应力T型梁。桥面荷载计算鉴于作用于桥面上荷载的复杂性，目前广泛采用的办法是将空间问题转化为平面问题求解。需要引 关键词　预应力混凝土；简支梁桥；桥墩；重力式桥台；钻孔灌注桩 Abstract Bridge is one of the most important traffic facilities,the design is about a reinforce concrete simply supported gieder bridge, that has Four spans.The bridge deck slab’s net breadth is 9+2×0.75 meter ,The clearance under bridge superstructure is 5 meter and each span to 45 meters.This design is composed.of three parts as follows:(1) the design of deck slab.Considering all of the factors,we decided use of prestressed bridge T-simple beam.The prestressed bridge has mang good qualities,such as it has small weight when installed, it is very simply when construction.And not use so much template.It is suitable for the small bridge.The bridge deck slab is composed of 5 T-simple beams,and the hollow slab is 2.1meter wideth,2.4 meter heigh and 44.96 ength.Considering the load is not simple,the bridge deck slab’scalauation,using the method of changing the space problem into plane design problem to draw thecolution.So we have to introduce the transverse load distribution factor.The loads that imposedon the bridge are as follows: constructure gravity prestressing soil gravity,concrete structure’s shrinkage and creep that casued influence force,the car load and impact force,trailer load pedestrian load and lateral earth pressure.The basic principle is that we neglect the link effect of the transversal constraction between the main girder.And supposed the bridge deck slab as simply-supported girder that is supported on the main beam.We draw the influence line that which point is the most adverse,from witch we can know the transverse load foundation’s sedimentation,to ensure it suit to the require of the standard.The bridge’s underside structure is installed under the foundation soil,its main use is to