NUMERICAL STUDY OF COMPOSITE RC SLABS WITH ECC RETROFITTING SUBJECTED TO BLAST LOADING

• Main Author: Irfan Fathin Izuddin, Muhammad
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/62416
• Institution: Institut Teknologi Bandung

Terrorist activities that are increasing prevalently in this era make the design of structures that are resistant to explosion become one of the major considerations when constructing a building. Facade concrete panels are structures that located at the front of the building. This structure plays a role, one of which is to protect the building from the threat of damage that may occur through the front of the building. If there is an explosion in front of the building, then the facade structure will be the first to be affected by the effects of the load due to the explosion. The modeling of facade structure is carried out to see the response and the damage pattern of the structure due to blast load. This structure is considered as a composite reinforced concrete slab with supports in the lower of the slab. The blast load is applied to the top of the slab. The responses of structure to be analyzed are maximum displacement, residual displacement, and maximum angle of rotation with the damage category referring to ASCE/SEI 59-11, 2011. ECC (Engineered Cementitious Composites) material is a material that has a tensile strength of up to 20% of the structure with a mixture of steel fibers and PVA in it. The behavior of this material in receiving loads is different from normal concrete. In ECC material, when cracks begin to occur this material will not immediately experience damage but will occur multiple cracks until the material's strength limit is reached. This is expected to help the structure to reduce damage due to explosions. The parameters reviewed from modeling simulations in this study are divided into several cases, such as variations in the compressive strength of concrete, fC’ (30, 40, and 50 MPa), variations in boundary condition (all pinned ends and 2 pinned 2 rollers), variations in the yield strength of reinforcing steel, fy (280 and 395 MPa), variation of spacing between reinforcement, s (150, 75, and 50 mm), variation of blast load (5 Kg at a distance of 1 m from the slab, 50 Kg at a distance of 10 m from the slab, and 100 Kg at a distance of 10 m from the slab), and structural variations using ECC retrofitting (ECC retrofitting with a thickness of 10 mm on the top and bottom slab, ECC retrofitting with a thickness of 25 mm on the top and bottom slab, the concrete material replaced by using ECC). Parametric studies were conducted to see the effect of the parameters tested in the modeling on the responses of the structure that occurred from the modeling results. Based on the results of the simulations, it can be seen the structure that gives a better response in receiving blast load is obtained by adding steel reinforcement and retrofitting the structure with ECC. By making changes of the space between steel reinforcement, from the space between steel reinforcement of 150 mm to 50 mm, it was found that a decrease in the maximum displacement was 35.060%, the residual displacement was 39.266%, and the maximum angle of rotation was 35.683%. In the analysis using ECC reinforcement with a thickness of 25 mm on the upper slab and lower slab, it was found that the decrease in maximum displacement was 78.860%, residual displacement was 50.461%, and maximum angle of rotation was 79.512%. As for the damage pattern, it was found that the structure with ECC retrofitting provided a much better damage pattern in receiving the blast load.