Climate Chamber
The climate chamber allows experimental simulation of rainfall-induced landslides (Askarinejad 2013). It is equipped with a custom built rainfall simulator, capable of imposing controlled intensity and duration precipitation. The rainfall is applied by non-uniformly distributed nozzles, extended below the strong box roof to a certain height above the slope surface to reduce the Coriolis Effect. The occurrence of overland flow (runoff) is dependent on the difference between the hydraulic conductivity of the soil and rain intensity.
Evaporation is controlled by means of air flow and increase in the ambient temperature in the drying phase of the tests. The air flow is provided by two air valves, one installed in the direction of the centrifugal rotation and one in the opposite direction. The pipe connected to the inlet valve is wrapped in a high resistance wire coil to heat the air. The relative humidity and temperature is measured at two points over the slope. Together with the suction build-up in the soil, they provide the necessary information to control the evaporation process.
The water supply of the rain simulator is composed of a central water tank (CWT), magnetic valves, pipes and water channels grooved into the chamber. The water height in the CWT is monitored by a pressure difference sensor (PDS-Keller PD11). The water flow from the CWT is controlled by two magnetic water valves. High pressure pipes convey the water from the tool platform to the climate chambers, which are installed diametrically opposite to each other.
A triangular aluminium frame with 38° inclination simulates the bedrock. Its top surface is coated with sand (same with the overlying layer). Water can be pumped through pipes into the slope to simulate the exfiltration of water from the bedrock. The rain water that has infiltrated into the soil can be drained through filter stones to model fractured bedrock. The top surface of the bedrock is equipped with 8 sensor slots (e.g., pore pressure transducers). Sensors can be installed at the soil-bedrock interface, but also inside the soil mass.
