Sains Malaysiana 41(2)(2012): 193–198
Kekuatan Geomekanik Batuan Granit dan Syis di Semenanjung Malaysia
(Geomechanical Strength of Granites
and Schists of Peninsular Malaysia)
A. Ghani Rafek & M. Hariri Ariffin
Program Geologi, Pusat Pengajian Sains Sekitaran dan Sumber Alam
Fakulti Sains dan Teknologi, Universiti Kebangsaan Malaysia
43600 Bangi, Selangor D.E. Malaysia
T. L. Goh*
Geoscience Department, Subsurface Division, Petronas Research Sdn. Bhd.
Lot
3288 & 3289, Off Jalan Ayer Itam, Kawasan Institusi Bangi, 43000 Kajang
Selangor
D.E. Malaysia
Received: 12 April 2011 / Accepted:
19August 2011
ABSTRAK
Kekuatan geomekanik bahan batuan memainkan peranan penting dalam mempengaruhi kestabilan struktur seperti pemotongan cerun dan pengorekan bukaan dalam jasad batuan. Ciri kekuatan jasad batuan di mana struktur-struktur ini dibina adalah dipengaruh oleh ciri bahan dan keadaan luluhawa. Kertas ini memperkenalkan hasil kajian sistematik pengkuantitatifan ciri-ciri mekanik batuan granit dan syis segar dan terluluhawa sedikit daripada beberapa lokaliti di Semenanjung Malaysia. Sejumlah 1,013 ujian kekuatan geomekanik telah dijalankan untuk bahan batuan segar dan terluluhawa sedikit dengan menggunakan ujian kekuatan mampatan sepaksi, ujian kekuatan regangan Brazil dan indeks kekuatan beban titik. Analisis statistik hasil ujian pada aras keyakinan 95 peratus memaparkan bahawa purata kekuatan mampatan granit segar dan terluluhawa sedikit ialah 113.6±7.0 dan 68.9±3.6 MPa, sementara nilai bagi syis segar dan terluluhawa sedikit pula ialah 137.3±9.2 dan 84.8±5.1 MPa. Seterusnya, nilai purata kekuatan regangan granit segar dan terluluhawa sedikit ialah 8.8±0.4 dan 5.3±0.1 MPa manakala nilai purata syis segar dan terluluhawa ialah 17.1±0.9 dan 10.5±0.4 MPa. Purata kekuatan beban titik granit segar dan terluluhawa sedikit ialah 9.4±0.30 dan 5.6±0.10 MPa manakala nilai syis segar dan terluluhawa sedikit ialah 10.9±0.42 dan 7.0±0.10 MPa. Hasil kajian menunjukkan bahawa kekuatan geomekanik bahan batuan segar menyusut lebih kurang 1/3 setelah tahap perluluhawaan bahan batuan tersebut menurun ke peringkat luluhawa sedikit.
Kata kunci: Granit; ujian indeks kekuatan beban titik; ujian kekuatan mampatan sepaksi; ujian kekuatan regangan Brazil; syis
ABSTRACT
The geomechanical strength of rock materials plays a significant role in influencing the
stability of structures like cut slopes and excavation of opening in rock mass.
The strength characteristics of rock mass where these structures are
constructed are influenced by both material characteristics and the condition
of weathering. This paper presents the results of a systematic research to
quantify the mechanical characteristics of fresh as well as slightly weathered
granites and schists of Peninsular Malaysia. A total
of 1,013 geomechanical strength tests were conducted
for both these lithologies for fresh as well as
slightly weathered rock materials employing the uniaxial compressive strength test, Brazilian tensile strength as well as the point load
strength index test. Statistical analysis of the results at 95 percent
confidence level showed that the means of compressive strength for fresh and
slightly weathered granites were 113.6±7.0 and 68.9±3.6 MPa while the respective values for fresh and slightly weathered schists were 137.3±9.2 and 84.8±5.1 MPa.
Subsequently, the respective mean values of tensile strength for fresh and
slightly weathered granites were 8.8±0.4 and 5.3±0.1 MPa while the values of mean for fresh and slightly weathered schists were 17.1±0.9 and 10.5±0.4 MPa, respectively. For the
point load strength, the means for fresh and slightly weathered granites were
9.4±0.30 and 5.6±0.10 MPa whereas the respective
values for fresh and slightly weathered schists were
10.9±0.42 and 7.0±0.10 MPa. The results of this
research revealed that the geomechanical strengths of
fresh rock material deteriorated by approximately 1/3 when weathering grade of
the rock material reduces to slightly weathered rock materials.
Keywords:
Brazilian tensile strength test; granite; point load strength index test;
schist; uniaxial compressive strength test
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*Corresponding author; email: gdsbgoh@gmail.com
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