Engineering characteristics and environmental impacts of the expansive Ankara Clay, and swelling maps for SW and central parts of the Ankara (Turkey) metropolitan area

Erguler Z., Ulusay R.

ENVIRONMENTAL GEOLOGY, vol.44, no.8, pp.979-992, 2003 (Journal Indexed in SCI) identifier identifier

  • Publication Type: Article / Article
  • Volume: 44 Issue: 8
  • Publication Date: 2003
  • Doi Number: 10.1007/s00254-003-0841-y
  • Title of Journal : ENVIRONMENTAL GEOLOGY
  • Page Numbers: pp.979-992


Volume-changing clay soils constitute the most costly natural hazard to buildings on shallow foundations. With the existing expansive clays in Ankara, low-rise buildings at the southwest part of the city have shown damage resulting in considerable maintenance costs. This paper reports the findings of an experimental investigation emphasizing the swelling behavior of Ankara Clay and correlations between the swelling parameters and other soil properties, and present a synthesis of observed damage details. The poor performance of the affected light-weight structures is assessed in the light of environmental conditions. In addition, swelling maps for SW and central parts of the Ankara metropolitan area, based on measured and predicted swelling parameters, are constructed for the purposes of land-use planning and general assessment of environmental problems. The experimental results suggest that the clay has high-to-very high activity, depth of active zone generally ranges between 1-2 m, the use of remolded and desiccated specimens seems to be a better approach in swelling tests, and the empirical equations based on two or more index or physical properties are good predictors for the estimation of the swelling potential of the clay. High swelling pressures exerted by the soil, flat topography and poor drainage, climatic conditions and poor construction methods are the main reasons of the structural damage observed at the study site.