Research On Economy Of The Cast-in-place Floor In Different Span

Not only structure composition,but also the economic benefit,floor play an important role in building.As a part of building structure,floor could transfer.The vertical load and turn horizontal load into the vertical load,at the same time,it can guarantee the integrity of the building.From the aspects of economic,the whole building cost more than 1/5 in floor.The economy of the floor associated with the number of layers,the more layers,the greater the cost of floor,modern public buildings and civil construction of the building height continued to increase,which prompted the overall cost of floor elevation.With the development of modern life and entertainment needs,more and more large span floor structure to be used,because construction needs not only provides a greater use of space,but also to meet the aesthetic importance.In sum total factor,it is very necessary to choose suitable types of slabs in the design of building structure.This article describe the six floor form,which is one-way slab,two-way slab,main and secondary girder,well-shaped beam,girderless floor and prestressed beam,and comparing their economic performance.The article provides the same external environment,namely,set the parameters according to the environment in Shenyang region.To ensure consistency of external conditions,comparison of different materials and various types of floor price,through changes in the span of each floor.Taking into account the various floor own to their appropriate span.The span is set between 6m to 10m transformation include one-way slab,two-way slab and girderless floor,and main and secondary girder,the well-shaped beam,prestressed beam,seting the span range is from 9m to 15m.In order to obtain more specific data,Span from 6m and 9m increments with 1.2m of span(including 6m,7.2m,8.4m and 9.6m;9m,10.2m,11.4m,12.6m,13.8m and 15m),making the conclusion more reference value.The number of spans Identified as four span,five span and six span,according to the size of column.In this paper we obtain the calculation of floor engineering quantity,by the application of PKPM software,establishment of model and parameter setting.Quantities derived from the software,including the amount of floor reinforced concrete volume and the amount of template.Then refer to analyze the structure of beams' and plates' highly Floor,the factors of cracks and deflections and others.According to the two-span range,Arrangement of the merits of the order for several of floor form,in the aspect of raw material,structure height,deflection and size of the crack.Based on the above factors,arrangement of the floor of the merit-based selection in a particular span.After calculation we can conclude that floor price from low to high as unidirectional,two-way slab and girderless floor column spacing between from 6m to 9m.In between the column spacing from 9m to 15m,main and secondary girder has the lowest cost.Among them,column spacing between 9m to 11m,well-shaped beamr cost less than prestressed beams floor.Column spacing between 13m to 15m,prestressed beam floor price is relatively less.When the column grid is 12m,the cost of well-shaped beam and p prestressed beam is the same.In terms of structural height,girderless floor structure has the minimum height of the structure.Prestressed floor also own an absolute advantage,and the structure of one-way slab is less than the height of two-way slab.Main and secondary girderr structure height is smaller than the well-shaped beam.Prestressed beam floor has obvious advantage in deflection and crack index.Two-way floor two technical indicators were less than one-way floor.Well-shaped beam deflection and crack less than primary and secondary beams.