Mode of slope failure of moderately to completely weathered metasedimentary rock at Bukit Panji, Chendering, Kuala Terengganu

Geology of Bukit Panji, Chendering, Kuala Teregganu consists of interbeded
metasedimentary rocks (slate, phyllite and schists with minor quartzite) which have
experience regional metamorphism. The age of this rock is Carboniferous. A
development project which under construction in Bukit Panji, Kuala Terengganu has
enabled a landslide assessment to observe the modes of failure in moderately to
completely weathered metasedimentary rock. Development on hillsides caused many
slope had to be cut to provide space for the infrastructure construction. From assessment
analysis, a total of 21 cases of landslide failure occurred involving 17 cut slopes, and 4
cut-fill slopes. The most common type of failures is gully failures, with 9 cases represent
43% of all the observed slope failure. This was followed by 6 wedge failures, two planar
and rock fall failures and one shallow sliding and toppling respectively. Cut slope failure
involving moderate weathered rock mass (grade III) to the residual soil (grade VI). Relict
structure was identified as the main factors controlling the failure, as well as water,
natural slope-forming materials and the use of appropriate slope stabilization