Bulletin of the Geological Society of Malaysia, Volume 46, May 2003, pp. 107 – 110

Pencirian geomekanik batuan syis grafit Bt. Bujang, Kuala Kubu Baru, Selangor Darul Ehsan

(Geomechanical characterisation of a graphitic schist at Bt. Bujang, Kuala Kubu Baru, Selangor Darul Ehsan)

ABDUL GHANI RAFEK, NG CHEONG KEAT DAN ABDUL RAHIM SAMSUDIN

Pusat Pengajian Sains Sekitaran dan Sumber Alam, Fakulti Sains dan Teknologi, Universiti Kebangsaan Malaysia, 43600 UKM, Bangi, Selangor D.E.

Abstrak: Pencirian geomekanik batuan syis grafit dari Bt. Bujang, Kuala Kubu Baru, Selangor Darul Ehsan dilakukan dengan pemetaan profil luluhawa, survei seismos biasan, ujian pantulan tukul Schmidt, ujian indek kekuatan beban titik I_S(50)[MPa] dan ujian kebolehtahanan pemeroian Id₂(%). Nilai halaju sebenar gelombang P, Vp bagi gred luluhawa I ialah diantara 2,000-2,500 ms^-1, gred II diantara 1,500-2,000 ms^-1, gred III diantara 900-1,500 ms^-1, gred IV diantara 750-900 ms^-1, gred V diantara 400-750ms^-1 dan gred VI diantara 250-400 ms^-1. Ujian mekanik batuan dilakukan atas bahan yang bersifat batuan, iaitu gred I, II dan II. Bagi gred I, nilai purata pantulan tukul Schmidt ialah 22, I_S(50) ialah 0.99 MPa dan Id₂ ialah 90.32%. Masing-masing nilai purata bagi gred II ialah 16, 0.34 MPa dan 83.81 % manakala untuk gred III ialah 11, 0.13 MPa dan 75.47%. Gabungan nilai indeks kekuatan beban titik dan kebolehtahanan pemeroian dapat membezakan tiga gred luluhawa ini secara kuantitatif.

Abstract: The geomechanical characterization of a graphitic schist from Bt. Bujang, Kuala Kubu Baru, Selangor Darul Ehsan was carried out using weathering profile mapping, refraction seismic survey, Schmidt hammer rebound test, point load index strength I_S(50)[MPa] and slake durability test, Id₂(%). The true P-wave velocity, Vp for weathering grade I was between 2,000-2,500 ms^-1, grade II between 1,500-2,000 ms^-1, grade III between 900-1,500 ms^-1, grade IV between 750-900 ms^-1 , grade V between 400-750 ms^-1 and grade VI between 250- 400 ms^-1. The rock mechanics tests were conducted on rock material, that is grade I, II and III. For grade I, the average Schmidt hammer rebound value was 22, I_S(50) was 0.99 MPa and Id₂ was 90.32%. For grade II these values were 16, 0.34 MPa and 83.81 % and for grade III they were 11, 0.13 MPa and 75.47%. A combination of the point load index strength values and the slake durability values enabled a quantitative differentiation of the three weathering grades.

https://doi.org/10.7186/bgsm46200318