INTEGRATED GEOTECHNICAL AND MINERALOGICAL CHARACTERIZATION OF INDIGENOUS ROCKS FOR SUSTAINABLE CONSTRUCTION MATERIALS IN THE NORTH WESTREN HIMALAYAS — DISTRICT NEELUM , AZAD JAMMU & KASHMIR, PAKISTAN

Abstract

In the construction industry, the quality of raw materials like aggregates is of
paramount importance. The use of non-durable or weak materials in a project's foundation can lead to
structural failures, posing significant risks to both property and human safety. Geotechnical laboratory
testing is essential to determine the strength and durability of these materials. Standard tests include
Uniaxial Compressive Strength (UCS), Los Angeles Abrasion Value (LAAV), Aggregate Impact
Value (AIV), Ultrasonic Pulse Velocity (UPV), specific gravity, water absorption, unit weight, and
Schmidt hammer rebound tests. While these tests are crucial for assessing mechanical properties, it is
equally important to consider the rock's mineralogical composition. A rock may exhibit high strength,
but the presence of certain reactive minerals can initiate deleterious reactions over time. This study
evaluated rocks from the Tithwal to Kel area in the Neelum District of Azad Kashmir for their
suitability as construction material. The Uniaxial Compressive Strength values range from 52.66 MPa
to 121.20 MPa. The Aggregate Impact Value ranges from 7.33% to 22.44%. The Los Angeles
Abrasion Value ranges from 22.3% to 37.2%. Schmidt Hammer rebound values range from 40.33 to
50.33 Nm. Unit Weight values range from 1.73 to 2.48. Ultrasonic Pulse Velocity values range from
22.56 to 47.07 Hz. Specific Gravity values range from 2.45 to 5.82.The results indicated that, from a
geotechnical perspective, all sampled rocks met the necessary strength criteria. However, it is
recommended that some of these rocks be used with caution due to the presence of quartz minerals,
which can participate in Alkali-Silica Reaction (ASR) when in contact with cement, potentially
causing long-term durability issues.