Student Name: SALINI V
Guide Name: Dr Satheeshchandran R, Professor, CE, GEC Barton Hill
Project Area: FLOODING
Year: 2020 , Duration: 1
Many states of our nation experienced unprecedented floods in the past few years,
causing widespread damage to structures and embankments. It is reported that many structures
failed due to the tilting and settlement of foundation which occurred during submergence. This
paper investigates the impact of floods on the settlement behaviour of shallow foundation. The
results of a series of laboratory scale load tests and finite element analyses carried out to
determine the influence of sudden submergence and drawdown on the settlement of footings are
presented. The effects of three types of submergence are studied; due to sudden rise of ground
water, drawdown of water and due to sudden inflow of surface water. The reduction of
settlement is evaluated by the introduction of sand compaction micro pile with this test set up.
Laboratory scale load tests on model circular footings are carried out in a masonry tank of
internal dimensions 1000 x 750 x 750 mm. The tank has arrangements for pumping in water and
drawdown. The influence of rate of submergence on settlement is studied by varying the
discharge of inflow of water.
Initially the model footing will be kept at the soil surface and the estimated safe load is
applied. The load is measured using a proving ring and settlement measured from two dial
gauges kept diametrically opposite to each other. After the settlement ceases, the tank is flooded
and the additional settlements are recorded. Finite element analyses are carried out with the
software PLAXIS 2D. The circular footing is modelled with an axi-symmetric model available in
the software. The soil is modelled with Mohr-Coulomb model. It is observed that the settlement
of footing considerably increases due to sudden submergence of footing. The settlement is
observed to depend on the rate of submergence.
Keywords: Flood, Shallow foundation, Laboratory scale load tests, Micropiles, Finite element
analysis, Settlement.
