STUDY OF ENGINEERED CEMENTITIOUS COMPOSITE (ECC) MECHANIC CHARACTERISTICS WITH VARIATIONS OF CONTENT AND LENGTH OF COIR FIBER

• Main Author: Anwar Farizan, Zaki
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/66916
• Institution: Institut Teknologi Bandung

Engineered Cementitious Composite (ECC) or generally known as bendable concrete in one type of high performance concrete (HPC) with the constituent materials of fine aggregate, cement, fly ash, superplasticizer, water, and the use of fibers up to 2% volume fraction. Coarse aggregate is not used in ECC. With the use of fibers and elimination of coarse aggregate, ECC has deflection-hardening in bending and fiber-bridging produce in ECC cracks. The fiber that used in this research is coir fiber. This research focuses on the mechanical characteristics of ECC or bendable concrete with variations in volume fraction of coir fibers i.e. 1% and 2% volume fraction and variations in the length of coir fiber, namely 12 mm, 30 mm, and a combination of 12 mm and 30 mm. The tests carried out were fiber tensile strength test, fresh concrete test (slump test and slump loss) and hardened concrete test (compressive strength, modulus and Poissons’ ratio, and flexural strength). The tensile strength of coir fiber is 117,18 MPa and the elongation is 51,84%. The slump value is significantly influenced by the number of fiber volume fractions used due to additional friction. Slump loss that occurs in fresh concrete ECC coir fiber is 53-75% within 120 minutes. The average of compressive strength of ECC coir fiber aged 28 days was 26-36,8 MPa. The highest compressive strength is ECC 1% coir fiber with fiber length of combination of 12 and 30 mm. The modulus value for ECC 1% coir fiber is 24,19-28,41 GPa, higher than the modulus value for ECC coir fiber 2% which is 21,03-23,75 GPa. Poissons’s ratio for ECC of 1% coir fiber is 0,25-0,4 which is not that far than Poisson’s ratio for ECC of 2% coir fiber of 0,22-0,47. The use of coir fiber had no significant effect on increasing the flexural strength of ECC concrete. The average flexural strength of the ECC of coir fiber is 3-3,33 MPa. The highest flexural strength of ECC coir fiber is owned by ECC coir fiber 1% with a combined fiber length of 12 mm and 30 mm. The development of ECC with coir fiber needs more specific research that contain the properties of coir fiber because of the effects of coir fiber that can affect the mechanical properties of ECC.