| Title |
Structural Performance of Waffle Shaped Precast Prestressed Concrete Slab |
| Authors |
Heo Seok-Jae ; Cho Seung-Ho ; Roh Young-Sook ; Park Tae-Won ; Lee Sang-Hyun ; Chung Lan |
| Keywords |
Precast Prestressed Concrete ; Waffle Shape ; Double-Tee Slab ; Bending Performance ; Shear Performance |
| Abstract |
Precast prestressed concrete provides high-quality structural elements, construction efficiency, and saving in time and overall cost of investment. Precast Prestressed Concrete had been widely used during 1990's specially those for apartment buildings. Despite of all the advantages of Precast Concrete, domestic demand was decreased due to technical difficulties for consistent quality control and maintenance problems. However precast prestressed concrete structure have become prevalent in the large parking garage and complex sales industry in recent years. The main object of this study is to investigate structural performance of Waffle Slab which was developed at our research center to improve connection problems. Experimental parameters are the number of prestressing wires and with/without truss girder on slab for flexural performance test. Also test parameter are the stirrup intervals(150mm, 200mm, 250mm) and with/without truss girder for shear performance. A total of 14 full-scale specimens were manufactured and waffle slab size is 1.98m?10.80m. Increasing number of prestressing steel wire provides significant increase of the flexural strength but it causes brittle failure mode. In case of using truss girder, structural performance was improved due to increase of bond strength between waffle slab and topping concrete. Shear capacity test showed that the stirrup interval of 150mm specimen exhibited more brittle behavior than those of 200mm or 250mm specimens. Proper regulations of the number of steel wires and stirrup intervals are necessary for ensuring ductile behavior of waffle slab. |