2018 - Nepal - Gravel Loss Model

Gravel loss is the change in thickness i.e. reduction in thickness of gravel roads surfacing over a period of time. For effective maintenance management of gravel road, a gravel loss prediction model works as a tool in selecting the optimal re-gravelling schedule. As gravel loss can be caused by many factors, for formulating a prediction model here average daily traffic (ADT) representing Traffic, absolute gradient (G) representing geometric design feature, mean monthly precipitation (MMP) representing climatic factors, plasticity index (PI), gradation of the aggregate (P20) representing surface material quality and the duration of observation in terms of day (D) are used as the model independent variable. The dependent variable of the model, gravel loss, are collected by observing the selected gravel roads in six month interval and the independent variables included in the model are gathered using standard procedures and methods. The selected roads for the study are NuwakotAsurkot-Pyuthan Road (Arghakhanchi district), Argha-Dharampani-Maidan Road (Arghakhanchi district), Sahid BasudevMarg,Ambhanjyang Road(Makawanpur district), Kabahigodh-Piparadi-Patarhati Road(Bara district), SonbarsaGadi-Sakhuwa-Parsauni– Mahuwan-Ramnagari Road (Parsa district), Bindawasni-Bairia-Birta Road (Parsa district), Bahurwabhatta-Pokharia, Padam Road (Parsa district). In each road a 60m of longitudinal grid are considered which are further divided into 10 m interval where elevation across the width of the road are observed using auto level. Model is developed using SPSS which will be helpful to find the residual life and appropriate time for re-gravelling.