THE EFFECT OF REPEATED IMPACT LOADING USING IMPACT TEST METHOD ON THE STRENGTH AND ULTRASONIC WAVE VELOCITY OF CONCRETE ROCK

• Main Author: Rahmat, Awaludin
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/85454
• Institution: Institut Teknologi Bandung

Mining activities can induce various impacts, one of which is rock fatigue. Rock fatigue occurs due to repetitive activities, causing a gradual increase in load on the rock, eventually leading to failure. Examples of repeated loads include vibrations from blasting and the use of heavy equipment. To investigate the impact of repeated loading on rock strength, this study employed the impact test method. The research commenced with physical property tests and ultrasonic wave velocity tests, followed by uniaxial compressive strength tests on concrete specimens. The specimens were prepared in two conditions: normal and saturated. During the testing, the specimens were subjected to repeated impacts from a height of 0.3 m, with the number of impacts varying from 4 to 12. Subsequently, uniaxial compressive strength tests were conducted to compare the compressive strength, Young's modulus, and Poisson's ratio before and after the impact tests. Results indicated that as the number of impacts increased, the strength of the specimens decreased. Saturated specimens exhibited a 17% reduction in both ultrasonic wave velocities (Vp and Vs) and compressive strength compared to their initial, non-saturated state. Furthermore, both compressive strength and Young's modulus decreased after the impact tests.