【关键词】 预应力简支空心板梁；装配式施工；预应力；
  Xingyi City Ma Ling Bridge (Simply-supported girder bridge)
【General description of the design 】
   Simply-supported girder bridge is a bridge from the two ends are supported by a bearing and a bearing on the beam as the main load-bearing structure. Belongs to the static structure. Is a beam bridge in the application of the earliest, the use of a bridge most widely. Its simple structure, convenient erection, the internal force of the structure is not affected by the deformation of the foundation, the influence of temperature change.
   Concrete beam according to the construction process into the overall style and assembly (tiled) two categories. Integral beam, the lateral stiffness, good stability. Because of the beam transport equipment hoisting capacity constraints, monolithic beam generally applicable to the in situ; and fabricated simply-supported beam bridge type is widely used at present.
   Concrete beam according to the load-bearing structure (beam) cross section forms, can be pided into the Banqiao, costal girder and box girder bridge. Its simple interface, convenient construction in bridge small span is frequently used in this section. Its applicable scope is used in the 4~8 meters span. Section form it and solid board, low floor, hollow board. If the use of prestressed, can reach 16m. Slab bridge structure due to low support surface is very wide, each piece is not lateral overturning, and need not any contact between the two beams. The integral rectangular solid plate has a simple structure , convenient construction, low construction height, structure of the overall stiffness headlight advantages. From the perspective of the stress, section material is not the economy, since the major, so only used in small span bridge. The span is too large is not suitable, because it's weight will be great, is a large part of its resistance have been eating its own weight. The span of hollow slab bridge in relative terms can be done relatively large. If the solid slab bridge, the main construction method of cast-in-place. If it is a hollow slab can be prefabricated, it will not be so high requirements for cranes. Its construction slightly to a little complicated, either in situ or prefabricated need the channel to stay out, so increase the difficulty of construction. But the stress is more reasonable than the solid slab, so the actual use of hollow slab bridge than the use of solid slab to wide. Of course, this is my personal imagination. But I think no matter from the stress angle or save the material point of view should take the form of bridge. Of course, there may be from the cost of the whole project or construction unit level comprehensive comparison.
  The main content of this design is the Xingyi City Ma Ling Bridge (bridge). Design of the three bridge project, respectively T shape rigid frame prestressed concrete beam bridge, continuous beam bridge, the recommended scheme for the prestressed simply-supported girder bridge.
  This bridge, the bridge length 20+20+20+20+20+20+20+20. The girder adopts hollow board, hollow plate section has the advantages of simple structure, clear force, convenient construction, mature technology, low building height, save the Bridge Approach Road Subgrade Earthwork occupation, economic, beautiful appearance, light, etc.. Hollow slab for bridge and bridge length shorter, smaller span bridge, long bridge long bridge and the bridge, the general should not be used, but in the across routing and design water level control deck elevation River, in order to reduce the approach embankment and the overall project cost, can consider to use 20 meters span hollow plate. Span 20 meters height comparison can be seen, the same span hollow plate beam with box girder high 25 ~ 30 cm, with 55 ~ 60 cm T Liang Ai. When the bridge is located at the line profile by bridge building height control, hollow plate beam has a great superiority of the. So 10 ~ 20 meters span hollow slab is widely used. Liang Gaowei height, the construction method of prefabricated beam. Pier adopts double column pier, foundation for the bored pile foundation. Fabricated simply-supported girder bridge can save a lot of formwork support, shorten the construction period, accelerate the construction speed, so widely used. Assembly type T shaped beam bridge is the advantages of low cost, good durability, high plasticity, high stiffness, small noise, is the use of a kind of bridge structure form the most common. Bridge deck pavement: use 8cm thick waterproof concrete as pavement, asphalt concrete wearing layer and 6cm, 14cm in total thickness. Bored piles of main pier foundation adopts 12 φ =1500; thickness of cap is 2.5m; in order to reduce the impact of water stress on bridge pier cap, two cap cross bridge side edge shape design is a circular arc, bridge pier with double column pier 混凝土简支梁按施工工艺设计+图纸(2):http://www.youerw.com/gongcheng/lunwen_7341.html