Experimental Study On The Flexural Behavior Of Prestressed Composite Slabs And The Analysis Of Related Problems

Nowadays,the most common floor forms used in the prefabricated buildings in our country is reinforced truss concrete composite slab.Common thickness standard of reinforced truss concrete composite slab is 180mm~250mm in Japan and Germany,which have mature technology in this respect.However,current national standard atlas,Reinforced truss concrete composite slab-60 mm thick base plate(15G366-1),extends the thickness of the laminated plate is only about 130 mm,which does not have an obvious influence on the bearing capacity of concrete floor steel truss.For this situation,in order to improve the bearing capacity reinforced truss to concrete bottom plate,the author propose to revise the national standard atlas,raising the steel truss string from C8 to C10,through the construction checking analysis.This is the first innovation point of this paper.Based on the research of prestressed laminated concrete slab in the period of postgraduate,the author suggests creatively for the above situation to replace reinforced truss concrete composite slabby the prestressed laminated concrete slab in the construction of prefabricated buildings.The standard atlas of prestressed concrete composite plates published in 2006,which is relatively backward in nowadays.The baseboard is prestressed flat plate in standard atlas.Therefore,the study on the performance of the prestressed concrete with ribbed slab still has great research space and application value.This is the second innovation point of this paper.To demonstrate the feasibility of replacing reinforced truss concrete composite slabby the prestressed laminated concrete slab,the author not only researches the bending stress performance of prestressed laminated concrete slab by calculation analysis and field controlled trial,but also compares and analyzes the effect of two schemes on the dosage of materials in two different architectural structures from an economic point of view.Combining the theoretical research of technical safety with the economic demand of market cost is the third innovation point of this paper.In view of these,this paper mainly completes the following research.It is put the prestressed laminated concrete slabas the research object in this paper.On the basis of the research on the development of existing laminated plates at home and abroad,presentted the design method of the prestressed laminated concrete slab and reinforced truss concrete composite slab,the Control experiment among three groups of subjects to test the Flexural Behavior is successfully completed.In addition,from an economic cost perspective,two calculation examples show the different material consumption and construction costs between using two types of floor covers.In view of safety and economy in the process of construction,it is explored that if it is possible to replace Reinforced truss concrete composite slabwithprestressed laminated concrete slab.Through the above research,the following conclusions are drawn:(1)Bending moment capacity of reinforced truss concrete composite slabis primarily influenced by base plate thickness,steel truss height and upper chord diameter.In order to improve the bearing capacity reinforced truss to concrete bottom plate,the author proposes to revise the national standard atlas,raising the steel truss string from C8 to C10.(2)Compared with reinforced truss concrete composite slab,prestressed laminated concrete slab has obvious advantage of the crack resistance.And its bending capacity can meet the design requirements,while it has disadvantage of ductility.Setting prestressed tendon in the rib can slightly improve its crack resistance and ultimate bearing capacity by 10% of prestressed laminated concrete slab.The later pouring concrete shear stress also has a little influence on the ultimate bearing capacity of prestressed laminated concrete slab.(3)It is shown from calculation and a brief analysis of economy it is an effective way to reduce cost and improve economic efficiency to replace reinforced truss concrete composite slab with prestressed laminated concrete slab.