Present study is aimed at assessment of Bholari river sand for its geotechnical characterization and suitability as fine aggregate which is being quarried in Jamshoro district, Sindh, Pakistan. For this purpose, sand samples (n=11) were collected from quarry sites and main river channel. Physical properties reveal that Bholari sand is mainly coarse to fine in size (0.2 mm-5 mm). Average values of fineness modulus, specific gravity, bulk density and void content of collected samples are 2.58, 2.56, 1659.90 kg/m3 and 35.12% respectively which varied within the corresponding permissible ranges of ACI (American Concrete Institute). Carbonate content of about 57.59% is also in agreement with corresponding range for fine aggregate. Petrographic examination revealed that Bholari River sand mainly comprises of quartz and rock fragments with subordinate limestone fragments. As per classification of Dott (1964), Bholari sand is lithic arenite where quartz (50%) occurs as main mineral followed by rock fragments (30%), feldspars (15%) and other opaque minerals (5%). Texturally, the sediments are angular (77%) to sub-round (33%). All these physical properties lie within the range set by National Highway Authority (NHA) and American Standard of Testing Material (ASTM). It is concluded that Bholari River sand is suitable for use in concrete mixed with cement and asphalt.

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Present study is aimed at assessment of geotechnical properties of Laki limestone as coarse aggregate which is being quarried in Nooriabad area, Sindh, Pakistan. Coarse aggregate samples (n=20) of limestone were collected for the evaluation of physico-mechanical properties of the aggregate. Petrographic analysis revealed that the aggregate comprises of hard, compact, massive, crystalline and fossiliferous limestone. It is devoid of any reactive silica (chert, chalcedony) and other harmful constituents like clays or organic matter. Average values of specific gravity, absorption,bulk density, void content and combined index (EI + FI) of collected samples are 2.5, 2.1%, 1.54 g/cc, 38.55% and 13.04% respectively. The values of specific gravity (2.3-2.9), absorption (0-8%), bulk density (1.28 g/cc-1.92 g/cc) and void content (30%-45%) are varying within the range of normal weight aggregate as per American concrete institute (ACI)specifications. On the other hand, absorption values of aggregate samples are slightly higher (2.1%) than the reference range (2%) but meet other requirements. Mechanical properties including aggregate impact value (8.58%), aggregate crushing value (26.66%), Loss Angeles abrasion value (24.77%), sodium sulfate soundness (4.72%), water soluble sulfate (0.006%) and water soluble chloride (0.005%) are found to be within corresponding guidelines set by ASTM. On the other hand, average carbonate content is found to be 89.64% indicating that Laki limestone is of slightly low purity. Except absorption, all physical and mechanical properties lie within specified ranges. It is concluded that Laki limestone is suitable for use as road aggregate and concrete mix design.