Preliminary modelling of hydro-thermal behaviour of ground reactive zone due to climate change

Climate change is no longer a topic restricted to scientific community. It has become a widely accepted fact by the general public as well. The effects of extreme weather conditions resulted from a changing climate are being sensed by every aspects of life. According to the predictions made by CSIRO (Commonwealth Scientific and Industrial Research Organization, Australia), there will be change in weather patterns with more hot days with an increased risk of bush fires in the future in Australia. These changes will cause distress to many urban and coastal structures including geo infrastructure such as pipelines, houses, and roads etc. This paper presents the numerical modelling work on the influence of climate change, more precisely the consequences of increased temperature and reduced precipitation, on hydro-thermal behaviour in ground reactive zone. Six locations with climate conditions varying from arid to wet were subjected to study. The Thornthwaite Moisture Index (TMI) of the selected locations ranges from -40 to 40 representing the different Australian climate zones. VADOSE/W finite element program was used to perform the numerical modelling tasks. Climate change predictions for Australia published by CSIRO were used as the input data. The equilibrium suction and the reactive zone depth (RZD) used for analysis were determined following four different criteria. Variations of soil moisture content/suction are predicted for a ten year period taking year 2030 as the base year. The simulated results generally indicate that ground will dry up further as the climate changes progress and equilibrium suctions in the ground will increase