Sains Malaysiana 40(5)(2011): 425–430

 

Application of Spectral Analysis of Surface Waves (SASW) Method: Rock Mass Characterization

(Aplikasi Kaedah Analisis Spektral Gelombang Permukaan (SASW): Pencirian Jasad Batuan)

 

T. L. Goh*, Abdul Rahim Samsudin & Abdul Ghani Rafek

Geology Programme, School of Environmental and Natural Resource Sciences

Faculty of Science and Technology, Universiti Kebangsaan Malaysia

43600 UKM Bangi, Selangor D.E., Malaysia

 

Received: 5 January 2010 / Accepted: 19 May 2010

 

ABSTRACT

 

A geotechnical study needs to be carried out to determine the engineering parameters of the rock mass at the project site in executing construction projects such as tunnels, dams, highways and buildings. Design and safety factor of the construction are highly dependent on soil and rock engineering parameters which are usually determined by in-situ test such as Standard Penetration Test (SPT) and seismic tests. The SPT test which normally involves drilling and laboratory works always incur high operating cost, while seismic tests on the other hand are fast, cheap, non-destructive and an easy to operate method for rock mass characterization. The spectral analysis of surface waves (SASW) method is an in situ and non-destructive measurement that is rapid and cost effective. The aims of this study were to determine Rock Quality Designation (RQD) value, excavation classification analysis as well as site characterization by using the SASW method. WinSASW 3.1.3 was used for inversion processing of the SASW data to produce shear wave velocity (Vs) versus depth profiles. The profiles were then analyzed and correlated with rock mass engineering geological parameters such as RQD and site characterization as well as excavation classification of rock mass. Twenty (20) SASW tests were conducted on the granitic rock mass and four (4) SASW tests were conducted on a cut hill slope of metasedimentary rocks. RQD values were computed based on shear wave velocities and ultrasonic velocities of intact (fresh) rock. The differences between RQD obtained from SASW method and those from discontinuity survey were found to be less than 10%. Excavation classification for granitic rock mass at JKR Quarry was empirically determined using both SASW and ultrasonic velocities as well as RQD value of the rock mass. Site characterization for metasedimentary rocks mass at Bukit Tampoi was determined based on shear wave velocities from SASW method.

 

Keywords: Excavation classification; rock quality designation; SASW method; site characterization

 

REFERENCES

 

Abdul Rahim Samsudin, Goh, T.L. & Abdul Ghani Rafek 2009. Application of spectral analysis of surface wave (SASW) for characterization of rock mass in engineering geology: case study in Malaysia. Geosea 2009, 11th Regional Congress on Geology, Mineral and Energy Resources of Southeast Asia pp. 62.

Arnie Salfarina Arshad 2005. Classification and characterization of rock engineering geology at JKR Quarry, Bukit Penggorak Kuantan, Pahang Darul Makmur. BSc Thesis. Universiti Kebangsaan Malaysia, Bangi.

Bay, J.A. 2000. Site characterization using the spectral analysis of surface waves method. Seminar at University of Alabama at Birmingham.

Caterpillar, T.C. 2006. Caterpillar Performance Handbook. Ed. 36th: Caterpillar Inc.

Cho, Y.S. & Lin, F.B. 2001. Spectral analysis of surface wave response of multi-layer thin cement mortar slab structures with finite thickness. NDT&E Internationals 34: 115-122.

Deere, D.U. 1964. Technical description of cores for engineering purpose. Rock Mech. Eng. Geol. 1: 16-22.

Deere, D.U. 1968. Geological Considerations, Rock Mechanics in Engineering Practice. New York: Wiley.

Joh, S.H. 1996. Advances in interpretation and analysis techniques for spectral analysis of surface waves (SASW) measurements. Ph. D Thesis. University of Texas.

Goh, T.L., Ghani Rafek, A., Rahim Samsudin, A., Hariri Arifin, M. & Baizura Yunus, N. 2010. Penentuan nisbah Poisson dengan menggunakan kaedah seismos. Prosiding Seminar Geofizik Kejuruteraan dan Sekitaran pp. 55-64.

Mohd Azmi Ismail, Khairul Anuar Mohd Nayan, Abdul Rahim Samsudin & Abdul Ghani Rafek, 2001. Spectral analysis of surface waves method: an initial assessment and its potential use in geology. Geological Society of Malaysia Annual Geological Conference: 185-190.

Nazarian, S. & Stokoe II, K.H. 1984. In situ shear wave velocity from spectral analysis of surface waves. Proc. of 8th World Conference on Earthquarke Engineering 3:31-38.

Rix, G. J., Bay, J. A. & Stokoe II, K.H. 1990. Assessing in situ stiffness of curing Portland cement concrete with seismic tests, Paper presented to Annual Meeting, Transportation Research Board, Washington, D. C.

Rosly Mohd. Nor. 1980. Geology of Kenny Hill formation Selangor, Peninsular Malaysia. MSc Thesis. Universiti Kebangsaan Malaysia, Bangi.

Suharsono 2006. Application of spectral analysis surface wave as new technique for rock mass classification in engineering geology. Unpublished Ph. D Thesis. Universiti Kebangsaan Malaysia, Bangi.

Suharsono & Abdul Rahim Samsudin 2003. The attenuation effects of surface wave propagations on rock mass using SASW method. Bulletin Geological Society Malaysia 46: 475-478.

Suharsono, Abdul Rahim Samsudin & Abdul Ghani Rafek 2004. Computation or rock quality designation (RQD) using spectral analysis surface wave method. Buletin Geological Society of Malaysia 49: 51-55.

 

*Corresponding author; email: gdsbgoh@gmail.com

 

previous