Carbonate Rock Evaluation

massive construction drive in Pakistan, necessitating the exploration
of diverse natural aggregate sources to sustain this development.
Therefore, this study delves into the petrographic characteristics and
mechanical properties of carbonate rocks from the Chichali Gorge
(Lockhart and Nammal Formations) and Zaluch Gorge (Amb
Formation) in the Western Salt Range, Pakistan. Employing
geotechnical analyses adhering to British Standards (BS) and
American Society for Testing and Materials (ASTM) standards,
various laboratory analyses were conducted. Simple regression
analysis unveiled interrelationships among physical parameters.
Petrographic scrutiny categorized Lockhart (LFPal) and Nammal
(NFEo) Formations as wackestone and Amb Formation (AFPm) as
mudstones. Calcite and bioclasts emerged as primary components,
shaping the limestones. Petrographic insights elucidated the rocks'
engineering traits, establishing correlations between petrography and
diverse physical and mechanical properties. Notably, Unconfined
Compressive Strength (UCS) and Unconfined Tensile Strength
(UTS) exhibited direct associations with calcite content but inverse
correlations with porosity and bioclasts. Rocks with higher porosity
and water absorption displayed diminished strength, while those with
lower porosity exhibited robust strength metrics. Based on these
analyses, LFPal and NFEo emerged as pivotal sources for small- and
large-scale projects, including CPEC. However, due to their elevated
silica content, caution is advised concerning AFPm aggregates. This
study provides valuable insights for construction endeavors, ensuring
informed material selection for optimal project outcomes in the
CPEC framework.