A Comparative Study on Properties of Riverbed Sand and Gravel of Different Selected Extraction Sites with in Sundarbazar Municipality, Nepal

Sand samples from four extraction sites of Marsyangdi river andthree extraction sites of Paundi river were collected. Similarly, gravel samples from three extraction sites of Paundi river were collected. Lab test for physical properties of sand and mechanical properties ofgravel were conducted on that sample to evaluate their quality for use in construction works. Lab testing were done as per IS 2386: 1963.After conducting the lab test of physical properties of aggregate, it is concluded that sand samples from Marsyangdi and Paundi river meet the standard value of specific gravity (>2.6), water absorption (<5%) and bulk density (1450–2082 kg/m3). Sieve analysis results showthat samples from Marsyangi river are poorly graded (Cu<4) whereas samples from Paundi river are well graded (Cu>4). Depending mainly on grading zone, Marsyangdi river sand lies in Zone II and III and can be used for concreting, plastering, rendering and screeding works. Similarly, Paundi river sand lies in Zone II and can be used in concreting works. On the basis of silt and clay content, Marsyangdi river sand samples are within the standard limit (5%) and Paundi river sand samples does not comply with the standard limit (5%) for use in construction. From result and analysis of Paundi river gravel samples, it is seen that gravelsamples lies in grading III and IV of Standard Specifications “For Road and Bridge Works-2073”. The particle size of gravel becomes finer as we move from upstream to downstream. Aggregate Impact Value (AIV) of all samples meet the criteria (<40%) of subbase material of class I and class II road construction works as specified by DoR. AIV decreases from upstream to downstream which means gravel quality in terms of strength increases as it move downstream. Comparing with standard specification of DoR, all samples have California Bearing Ratio (CBR) value greater than 30% which means it can withstand heavy loadswithout deformation.Keywords: Gravel Samples, Lab Test, Aggregate Impact Value, California Bearing Ratio How to cite this article:Subedi B, Banstola R, Baral NP, et al. A Comparative Study on Properties of RiverbedSand and Gravel of Different Selected Extraction Sites with in Sundarbazar Municipality, Nepal. J Adv Res Civil Envi Engr 2023; 10(2): 1-13.