STRUCTURAL BEHAVIOR OF EMBEDDED SHEAR HEAD IN MODIFIED REACTIVE POWDER FLAT PLATE CONCRETE WITH OPENING

الملخص

This study presents an experimental investigation on one type of embedded shearhead called ( collar head reinforcement) as shear reinforcement for tow type of reinforced concrete flat plate with presence of opening on punching shear strength. This type of shearhead is one of the structural solution that are used to increase the shear strength of flat slab . In the present research , ten specimens are tested with dimensions (1000x1000x75 mm) which are divided into two groups; the first group is a normal strength concrete with a compressive strength 30MPa; the second group is modified reactive powder concrete with a compressive strength 90MPa. Each group consists of five slabs. By using collar shearhead around the column sides and extended to the opening NSC4, the cracking load can be increased to 100% solid flat slab without collar head. For serviceability of flat plate with opening, the deflection and crack width can be reduced by using collar head around the column sides extended to the opening. The reduction can be continued by increasing the compressive strength of the concrete.