Finite Element Analysis And Optimization Design Of Reinforced Concrete Laminated Slab With Ribs

The research object of this subject is a kind of reinforced concrete laminated slab with ribs.Through the previous experimental study of the subject group,it is found that the slab has good mechanical properties.,However,only single-span single-rib reinforced concrete laminated slab has been studied experimentally.This paper is based on the experimental study of the research group,finite element software ABAQUS was used,this paper studies the influence of the mechanical behavior of the change of the rib size and the thickness of the ribbed prefabricated floor slab to the ribbed floor slab and ribbed laminated slabs,and the section sizes of single-ribbed,double-ribbed and full-concrete ribbed laminated slabs with different spans are optimized.The specific work and conclusions are as follows:(1)Using ABAQUS finite element software to simulate the experimental of the reinforced concrete laminated slab with ribs made by research group,the correctness of the model was verified.(2)Using finite element software to simulate the whole process of construction stage of ordinary reinforced concrete laminates slabs and ribbed reinforced concrete laminates slabs,the results show that the existence of concrete rib of ribbed reinforced concrete laminated slabs can effectively improve the rigidity of the bottom slab and improve the cracking load of the bottom slab,which in turn reduces the deflection extreme.(3)By changing the rib height and rib width of precast floor concrete rib,comparative analysis and research were carried out.The calculation results showed that the change of rib height had a great impact on the mechanical performance of precast floor during the construction stage,while the change of rib width had a small impact on it.Thispaper suggested that the rib width should be within 1/4 of the width of the floor as faras possible.(4)Finite element analysis of single-ribbed reinforced concrete floor with different thickness shows that the change of floor thickness has a great influence on the mechanical performance of single-ribbed floor during construction.The smaller the thickness of the floor,the lower the cracking load of the floor and the greater the deflection.When the thickness of the floor is reduced by 5 mm,the deflection increases by about 15%.(5)By changing the rib height and width of the concrete rib of the floor,the influence of the change of the size of the rib of the floor on the mechanical properties of the laminated slab in the normal service stage is studied.The results show that the change of the size of the rib has little effect on the deflection of the laminated slab,which is less than 5%.However,the increase of the height or width of the rib of the floor increases the cracking load of the laminated slab.(6)In the normal use stage,the change of the thickness of single ribbed reinforced concrete laminated slab has an obvious effect on the mechanical properties of laminated slab.The thinner the slab is,the smaller the cracking load is,and the larger the deflection is under the same load.The bearing capacity of laminated slabs decreases by about 8% when the thickness of slab bottom decreases by 5 mm.The thickness of single rib laminated plate is reduced to 115 mm(the thickness of bottom plate is reduced to 45 mm),and the bearing capacity and stiffness still meet the requirements of the code.(7)Finite element simulation of the whole construction process of double-ribbed reinforced truss concrete floor is carried out.The analysis results show that the spacing of concrete ribs of double-ribbed reinforced truss floor is about 1/2 of the width of the floor.Based on a large number of finite element simulation calculations,considering the economy and applicability,the optimal design of ribbed reinforced concrete laminated slabs with different spans is carried out on the premise that the stiffness and load-bearing capacity meet the requirements of the code.Finally,refer to the National Architectural Standard Design Atlas 15G366-1 of Truss Reinforced Concrete Composite Slab.The formwork and reinforcement diagrams of the bottom slabs of ribbed reinforced concrete laminated slabs with different spans are given,which will provide some references for further research and popularization of ribbed reinforced concrete laminated slabs.