Experimental Study On The Mechanical Performance Of H-shaped Steel Reinforced Concrete Slabs

With the rapid advancement of modern science and technology and the gradual changes in the future industrial structure,urbanization is now an important means of achieving transformation.At the same time,environmental problems,such as frequent smog,have become increasingly serious and have become a key factor restricting the construction of ecological civilization.Building reinforcement and reconstruction is an important weapon to solve the problem.Through scientific and effective reinforcement and reconstruction methods,construction resources can be used efficiently and the pollution of the construction industry to environmental resources can be reduced.The section steel reinforcement method uses shear connectors(anchor bolts)to connect the section steel and the structural members to be reinforced to form a composite beam.Using this method can increase the rigidity and strength of the members,and at the same time,the bearing capacity can be greatly improved.In this paper,13 H-shaped steel reinforced concrete slabs with different variables are used for static load testing.The main factors considered are connection method,bolt depth,number of anchor bolts(anchor bolt spacing),and bolt diameter.Observe the influence of these factors on the working performance of H-shaped steel-concrete slab through experiments.There are two kinds of connection methods: steel beams and floor slabs are connected by planting bolts;bolts directly pass through the floor slab to connect the concrete slab and the steel beam into a whole.The conclusions obtained through experiment and theoretical analysis are as follows:1.Connect H-shaped steel and concrete slab by means of planting bolts or penetrating the floor slab.The joint surface is leveled only with cement mortar.The concrete slab can be reinforced to form a steel-concrete composite beam structure.Although the concrete slab and the shaped steel beam will relatively slip under load,their overall working performance will be weakened,but they still have a certain overall working capacity,and their bearing capacity is much greater than that of the steel beam.2.The reinforced composite beam member,when the load is relatively small,the concrete slab and the steel beam can work together completely,the strain on the cross section is linearly distributed,and the slab and the steel beam act together as a composite member.When the load reaches a certain value,there will be horizontal cracks in the joint surface of the plate and the steel beam,slippage will occur between the two,and the internal force redistribution will occur in the component.The component has both the overall bending moment and the local bending moment of the plate and the steel beam.At the joint interface,the shear force is transmitted to the upper flange of the steel beam due to shearing of the anchor bolt,which generates an eccentric tensile force on the steel beam.The eccentric tensile force will have a negative negative bending moment effect on the steel beam.The magnitude of various internal forces depends on the plate Overall working performance with steel beam.At both ends of the beam with large shear force,the shear stress at the joint surface is relatively large,and it should be slipped and disengaged.The force model can be simplified as an arch with tie rods.3.There are two final failure modes of the component under load: the concrete slab produces diagonal cracks and shear failure;the concrete slab produces vertical cracks,the concrete in the compression zone is crushed,and the concrete slab is damaged by bending.4.When the anchor bolt spacing is fixed,the larger the anchor bolt diameter,the better the overall performance.If the depth of anchor bolt implantation is small,individual anchor bolts may be pulled out and become ineffective.Therefore,the anchor bolts should ensure a certain anchoring depth.5.The overall working performance of a member using a through-connection method is poorer than a member using a plug connection method.6.Strengthen the concrete slab with a steel beam,and form a steel beam and a concrete slab by setting bolt connectors,which can be calculated as a composite beam,but the bearing capacity should be multiplied by a reduction factor.The reduction factor is recommended to be 0.7.