Experimental Study Of The Assembled Monolithic Prestressed Hollow Slab

The assembled monolithic prestressed hollow slab is a combined application of prestressed technology and hollow slabs technology. The assembled monolithic slab is composed of the prestressed hollow slab which is used as bottom plate and the secondary casting composite layer. This structural system with great potential in the future has the characters of large span, light weight, convenience of construction and good applicability.In this paper, the research is mainly focused on the mechanical characteristics of the assembled monolithic hollow slab under vertical loads in elastic stage.Through the experiment of the assembled monolithic prestressed hollow s under static water, its working performances of elastic stage are studied and analyzed. The experimental result indicates that the working character of the test slab is typically two-way obviously. The longitudinal reinforcement and fold-line reinforcement are disposed in the longitudinal rib of side slot of the prestressed slab, the detailing negative reinforcement is disposed in the bearing of slab end,the connection of beam and the length direction of prestressed slab, the transverse reinforcement is disposed in the transverse rib between two slab at the bearing. The hole of slab end is filled with the block and cast with post-casting concrete. Those makes the floor with good integral performance,high bearing capacity and good cracking resistance.Finite element analysis program ANSYS has been used to analyse the testing model. The calculated force-displacement curve and distribution of inner-force distribution are conformed to the result of experiment.In the aspect of theoretical analysis, stiffness of RC two-way hollow slab have been analyzed according to elastic theory. The result show that flexural stiffness of hollow slabs is different on two ways because of cavity, and the stiffness is mainly dependent on the ratio between hole aperture and plate thickness(d / h), but the difference between them if small. According to this conclusion, the assembled monolithic hollow slab that researched in this paper can simplify as common cast -in-place hollow slab model. Based on the simplification, the equivalent slab method can be used to analyse inner-force to the computation model under elastic stage. Through large calculation for inner-force of different hollow slab models, some rules of inner-force distribution of hollow slab under vertical loads can be obtained.