Geotechnical study of marble, schist, and granite as dimension stone: a case study from parts of Lesser Himalaya, Neelum Valley Area, Azad Kashmir, Pakistan

Extensive production of concrete and bricks has reduced the use of stone masonry in construction. The overwhelming use of artificial material, especially concrete, has led to many environmental issues. Use of dimension stone is almost non-existent in general construction. Nonetheless, it is still widely adopted in foundations, facings, dams, coastal defenses, and retaining and water containment structures. For the possible rational replacement of artificial materials, marble, schist, and granite were selected for evaluation as dimension stones. Important properties influencing the behaviour of construction material, such as compressive strength, tensile strength, durability, water absorption, and petrography, were investigated on selected rocks. The results were correlated with standard specifications of ASTM, ISO 14689-1 (Geotechnical investigation and testing. Identification and classification of rock. Part 1: Identification and description 1-16, 2003) and Gamble durability index (1971). Regional faults, Main Boundary Thrust, and Panjal Thrust, present in the area influence the characteristics of rocks adversely. Granite has a lower compressive strength than the ASTM specification so it should be avoided for load-bearing masonry units and external pavements. Granites and marbles have a higher degree of water absorption. All three rock units have a very high degree of polish, so their use as decorative stone, especially as internal flooring and at internal walls, is highly recommended.