Stability Analysis of Soil Slope Subjected to Blast Induced Vibrations Using FLAC3D: Fid-Bau Portal

Stability Analysis of Soil Slope Subjected to Blast Induced Vibrations Using FLAC3D

Sangroya, Ritika / Choudhury, Deepankar

In this paper, stability analysis of dry cohesion-less soil slope of height 6m with buried pipeline with effect of blasting is carried out by using numerical method. Stage wise construction of soil slope and installation of concrete pipeline of 0.5m thickness and of 2m diameter is considered while doing numerical modeling using finite difference based geotechnical software FLAC^3D (Fast Lagrangian Analysis of Continua in 3 dimension). Soil in free-field condition for blasting is calibrated and the radial velocities obtained from FLAC^3D model are compared with empirical values from CONWEP program as well as velocities using scalar wave equation. Restricted zone for slope is defined as the area surrounding the slope where pipeline should not be installed to avoid the slope instability due to blasting. To propose this restricted zone, blasting in pipeline is carried out at 30 different locations in the foundation soil. It has been noticed that restricted zone for soil slope is up to the depth of 8.5m with respect to allowable peak particle velocity (PPV) and from depth of 4m to 9.5m with respect to allowable peak particle displacement (PPD) from the face of soil slope. The effects of lateral and longitudinal position of pipeline in foundation soil, property of foundation soil, location of blasting in pipeline on the slope stability are also evaluated which can provide a guideline for design of pipeline in soil slope where blasting can be expected.