Hollow Concrete Slab with Lightweight Steel Hollow to Mitigate Earthquake Disaster

Using lightweight building materials is one option to mitigate the structure of buildings and other civil buildings against earthquake disasters. This method aims to minimize the weight of the building as the magnitude of the earthquake that hits the building is directly proportional to the building's weight itself. The floor plate of the building is made of reinforced concrete with a weight of 240 kg/m. Therefore, this study used 30x30 mm lightweight steel hollow as a hole-forming and as a substitute for shrinkage and temperature reinforcement. This plate was assembled to flexural reinforcement with a diameter of Ø6 -100, the compressive strength of concrete (fc= 25 MPa), thus forming a one-way slab measuring 880x440x90 mm. After the slab had been cured for 28 days, the flexural strength was tested with an Automatic Tension & Compression Testing Machine having a capacity of 3000 kN. As a comparison, the test items were created of two samples with different hollow placements of 3, 4, 5, 6 hollow and solid plates. The major goal of this study is to determine the modulus of rupture (MOR), modulus of elasticity (MOE), and weight reduction owing to the use of lightweight steel hollows as hole-forming and replacement for shrinkage and temperature reinforcement in hollow concrete slabs. The results showed that using 5 and 6 lightweight steel hollows can reduce concrete weight by 10% to 14% while maintaining the maximum modulus of rupture and modulus of elasticity. However, when compared to solid plates, the modulus of rupture and modulus of elasticity were reduced by 60 to 65 percent.