EXPERIMENTAL STUDY AND PARAMETRIC ANALYSIS ON FLEXURAL PROPERTIES OF BILATERAL PRESTRESSED COMPOSITE CONCRETE SLABS WITH STEEL TRUSSES

A novel concrete composite slab was put forward by means of adding steel trusses and applying bilateral prestresses. The four specimens were tested to investigate the flexural behaviors of slabs influenced by the types of trusses. The failure modes, cracking loadings, loading deflection relationships and strain distributions, etc. were obtained by contrast experiments. The test results showed that the bilateral prestressed concrete precast panels present obviously bidirectional bending characteristics, and the bending stiffness, the cracking resistance, the bearing capacity and the ductile failure of precast panels were significantly improved due to adding steel trusses. In addition, precast panels with steel plate trusses, steel tube trusses and steel bar trusses all could meet the requirements of no supporting. By finite element parameter analysis, it was concluded that the height of trusses and the thickness of concrete had significant influence on the bending stiffness and the cracking resistance of precast panels. Meanwhile, the number of prestressing tendons had great effects on the cracking resistance but little influence on the bending stiffness.