Land subsidence modeling due to ground water drainage using "WTAQ" software

Abstract

Subsidence is settling of the earth's surface because of different factors. Ground movements, mining activities, gas, oil and water, withdrawal are some examples that can causes ground subsidence. In recent years it has been proven that in dry areas because of extensive ground water withdrawal, the rate of subsidence increases rapidly (more than 10 centimeters in a year). A decrease in ground water level will causes an increase in effective stresses at clay layers which results consolidation of lower layers. The behavior can be modeled using finite element technique to predict the future settlement. In this paper the relationship between classical soil parameters and parameters used in numerical is driven for a single well water table lowering. It is possible to approximate the model by assuming elastic time dependent behavior due to decrease in water table level that calculates with a computer software that's name is 'WTAQ" (Water Table Aquifer). For this purpose specialized finite element model was established and related to classical soil mechanics consolidation parameters. In this research subsidence of different lands in Sirjan and also Shahrekord are compared.