Faculty of Civil Engineering, UiTM

1. CORRELATION BETWEEN UCS AND P-WAVE VELOCITY FOR TROPICAL WEATHERED SANDSTONE IN SELANGOR Amy MelatiMokhtar, 2006132931, Faculty of Civil Engineering, UiTM Faculty of Civil Engineering, UiTM ABSTRACT This study is concerned on the correlation between Uniaxial Compressive Strength, UCS (σ) and Ultrapulse velocity (Vp) data for tropical weathered sandstone. 30 samples is extracting from Puncak Alam, Selangor. The blocks samples are then cored into cylindrical shape and the physical properties are record. Uniaxial compressive strength test and Portable Unit Non-destructive Indicator Tester test are carried out to determine the data P-wave velocity and UCS value. From the tests is perform to identify the value of UCS (σ) and P-wave velocity (Vp). The UCS data are correct (σc) and the data of P-wave velocity (Vp) are check. After that, graph of velocity versus UCS are plot to determine regression line thus empirical equation and coefficient are propose. Comparison between previous research and present research will be discussed and conclusion will be deduced. This study is concerned on the correlation between Uniaxial Compressive Strength, UCS (σ) and Ultrapulse velocity (Vp) data for tropical weathered sandstone. 30 samples is extracting from Puncak Alam, Selangor. The blocks samples are then cored into cylindrical shape and the physical properties are record. Uniaxial compressive strength test and Portable Unit Non-destructive Indicator Tester test are carried out to determine the data P-wave velocity and UCS value. From the tests is perform to identify the value of UCS (σ) and P-wave velocity (Vp). The UCS data are correct (σc) and the data of P-wave velocity (Vp) are check. After that, graph of velocity versus UCS are plot to determine regression line thus empirical equation and coefficient are propose. Comparison between previous research and present research will be discussed and conclusion will be deduced. PROBLEM STATEMENT RESULTS AND ANALYSIS • Sandstone is a sedimentary rock and classified as weak rock since strength test data were ranged from 0.25MPa to 25MPa as mentioned by Klien S. (2001) adopted by ISRM (1981). • Tedious and difficulties of determining sample from tropically weathered sandstone are very problematic experienced by geotechnical engineer in Malaysia (Mohamed et al., 2007 and Chang C. 2004). OBJECTIVES • To determine the uniaxial compressive strength (UCS) of tropical weathered sandstone. • To determine the P-wave of tropical weathered sandstone by conducting Pundit Test. • To obtain the correlation between UCS and P-wave of tropical weathered sandstone. LITERATURE REVIEW • The characteristic of weak rock are low strength, high deformability (lead to yielding, slabbing, spalling squeezing condition and reveling), and may have inconstant strength (rock may deteriorate). • Ultrasonic Pulse Velocity (UPV) data can be used along with strength data to estimate the engineering properties of rock (Chary K. B. et. al., 2006). • K.B. Chary et. al. (2006) have found good correlation between Ultrasonic Pulse Velocity & Uniaxial Compressive Strength. Schematic drawing of the particle movements in P-wave (Bolt, 1976). Classification of weak rock by weathering grade for more than one rock types as a unit rock mass (Mohamed et. al., 2007) CONCLUSION METHODOLOGY • Conduct UCS test and UPV test accordingly to ISRM. • Produce graph of UCS versus UPV data and determine empirical equation together with the coefficient of the plotted graph by using linear regression analysis. • This study has support the statement of previous researchers that the tropical weathered sandstone rock strength is not easy and could be complicated to determine due to uncertain characteristics. • Generating a correlation between UCS and P-wave velocity of tropical weathered sandstone is very important to gain deep understanding on the changes of physical behaviour and mass engineering of the sedimentary rock to be able to suit the demand of infrastructural developments and apply in the geotechnical assessment. ACKNOWLEDGEMENTS • Miss Noorfaizah Hamzah, (Supervisor for Final Year Project) • Faculty of Civil Engineering, UiTM