A Study on suitability of aggregates of Kavre and Sindhuli district quarries used in Kathmandu valley for different layers of Flexible Pavement

Abstract

This research work focuses on the measurement of quality and usability of road construction materials near the quarries of Kathmandu Valley (Kavre and Sindhuli Districts).To achieve the objectives, four local sources of Kavre & Sindhuli district are chosen from where large amount of materials can be transported to Kathmandu valley for road construction. The quarries chosen are Chalaal Ganeshsthan (Bethanthok – 4, Kavre), Bhyakur Khola at Kalo dhunga (Roshi – 11, Kavre), Ghyampe Khola at Aapghari (Sunkoshi – 01, Sindhuli ) and Om Buddha crusher at Kamere (Sunkoshi – 02, Sindhuli) . This study is mainly focused on the testing of quality of the aggregate as per Standard Specification of Road and Bridge Works (SSRBW), 2073 of department of roads for the construction of different layers of flexible pavement. This study may be useful for finding the nearby location of proper source of material required for road construction during the contract process of any project which reduces the time for finding out the material resources. For testing of aggregates, samples are collected from every sources of each type of materials which are produced on the nearby crusher. Collected samples are tested on the central laboratory of department of roads, Lalitpur. Relevant IS codes are adopted to conduct the various laboratory tests of the materials required, complying to the Standard Specifications for Road and Bridge Works, 2073of Department of Roads. As per the laboratory test result of physical properties, it is found that all the processed materials for every pavement component from each source are well graded. Compaction and mechanical strength of sub base from each source are good as maximum dry density is greater than 2.15g/cc and California bearing ratio is more than 60%. Also for base material of all sources, maximum dry density are more than 2.2g/cc , Los Angeles Abrasion (LAA) values are less than 40 %, Aggregate Impact value (AIV) are less than 30% , combined Flakiness & Elongation Index are less than 35 % & crushing ration (CR) more than 80%. , all sources material are suitable for base course. Similarly for Bituminous Macadam (open graded) of all sources, LAA is less than 40%, AIV is less than 30%, combined EI & FI is less than 35%, water