Rippability classification for quartzite based on specific energy and field production rate

Abstract

When rock is deemed to be rippable, it is essential to classify how difficult to actually rip this rock on site. The rating on the difficulty is termed as rippability classification, and it is based on mass and material properties of the rock which contribute to its resistance against ripping. This paper highlights a study to establish a similar classification for quartzite which is based on specific energy (SE) and field production rate (Qr). To facilitate in analysis of data, the study area (located in Dengkil, Selangor) is divided into 6 panels (A to F). Collected data are grouped according to these panels. Laboratory assessments include verification on cuttability and strengths of the rock samples. Seismic survey and in situ ripping test were field appraisals conducted to assess rippability of the in situ quartzite. Analysis of data indicates that besides its material properties, rippability of quartzite can be evaluated using its SE. Ranging between 3.19 and 6.19 MJ/m3, the SE is related to the Qr, which is between 147 and 292 m3/hr. For the six panels investigated, it is found that the higher the SE, the lower is the Qr (i.e. more difficult to rip). Based on the SE, Qr and horsepower of ripper dozer, rippability classification for the quartzite is established. This classification is essential for planning and costing of major earthworks, particularly in estimating capacity of ripper dozer and duration of earthwork.