Page 27 - BUKU PROGRAM SEMINAR SPESIFIKASI PIAWAI JKR KERJA GEOTEKNIK

DETERMINATION OF HARD MASSS AND ROCK MASS
ABSTRAK

The study aimed to assess hard mass and rock mass conditions for
road projects in Kelantan state. Fieldwork was conducted from April
8th, 2019 to January 8th, 2024, at a new road construction site
accessed via federal road 8 (FT8). The lithology of the area, based on
Geological Map of Peninsular Malaysia, comprises mainly pyroclastic
sequence (tuff) with thin layers of argillite and marble interbeds,
estimated to be 3000 meters thick, with an upper contact with
overlying Telong Formation.

Preliminary assessment defined hard mass as semi-cemented
sediments, weathered rock mass, and highly fractured rock mass.
Rock mass refers to fresh to moderately weathered rock. Excavation
criteria and production rates were specified. Confirmation of hard
mass and rock mass excavation required direct (machinery) and
indirect (point load test) verification.

Trial excavations were conducted using an excavator on a flat
platform. Production rates were determined based on excavation
depths and durations. Excavator condition and maintenance were
emphasized to achieve specified mechanical outputs. Ten samples
from trial excavations underwent point load tests using calibrated
apparatus. Samples sized between 30mm and 85mm were preferred,
with interpretations outlined in the specifications. Both direct and
indirect methods had to be satisfied for material classification.

The study adhered to the Standard Specification for Road Works JKR
Road Specification, JKR/SPJ/2020-Section 2 Earthworks. However, it
did not explore other rock mass strength estimation methods such as
Q-System, N-system, RMi system, RMR76, and GSI, which could
provide additional insights into rock mass quality and strength.

26 KERTAS TEKNIKAL