Bearing Capacity Of Experimental Study Of PK Prestressed Concrete Unidirectional Composite Slab

PK prestressed concrete composite slab is a kind of semi-cast and semi-cast slab,it consists of two parts,including the precast floor and the cast-in-place layer.Prefabricated slab produces in the factory,then transported to the construction site.the prefabricated base plate has ribs which reserve holes,a laterally distributed perforated reinforcing bar is arranged in the rib,when the upper layer of concrete is hard to form an integral composite plate.Because of the existence of the prestressing tendon and the reinforcement of the perforation,the laminated plates have good mechanical properties.This structure has the advantages of simple construction,economic environment and so on.So,this laminated should be widely promoted and used.Based on the analysis of PK board,this paper makes a more thorough and detailed analysis,to strive to PK board of the relevant technology more perfect.Its main research is as follows:Firstly,PK prestressed concrete composite slab belongs to semi precast semi cast structure.First of all,this paper introduces composite slab production method in factory,then,it introduces the construction technology of composite slab.Secondly,In the past,most studies have been carried out for the rectangular rib composite slab,less studies about “T” rib composite slab."T" rib slab is the second generation product of PK prestressed concrete composite slab,the design specification about “T” rib composite slab is not precise enough.In this paper,author uses the large-scale finite element software ANSYS to analyze the precast ribbed slab of the PK prestressed concrete composite slab,to check rationality of ANSYS with related report,then,analyzing ultimate bearing capacity of precast slab.Thirdly,Based on the analysis of ultimate bearing capacity of four prefabricated "T" ribbed bottom plates,we study the cracking condition,changing of load deflection of four precast floor slab,to determine their cracking load and ultimate load and prove their good performance and construction safety.Fourthly,Because the PK prestressed concrete composite slab is a prefabricated assembly structure,which determines characteristics of its multi stage.PK prestressed concrete composite slab from production to complete the construction of a total of three stress stage.It is different parts of force at each stage and the sources of stress arealso different.Finally,in this paper,the author made four prefabricated panels in the upper section to form a unidirectional laminate,using ANSYS to simulate the three force stages of them and analyzing the stress of the plate to prove that they are safe during construction.Author analyzes the bearing capacity of four PK prestressed concrete slabs,to get the cracking load and ultimate load of the composite plate and draw the curve of the load deflection.Finally,this paper analyses the variation law of the ultimate load of the plate with different span and reinforcement by comparing the load deflection curve of four pieces of composite plates.