Problems of clay desiccation in composite lining systems

Temporary works desiccation of composite lining systems is introduced as a potential problem. Field evidence for such desiccation is presented and the mechanism of desiccation discussed. Results from a laboratory testing programme, including a study of a heated test cell, are reported. In the cell, moisture loss caused crack development and, once an initial network of cracks was formed, further moisture loss was found to cause crack depth propagation. Solutions to the problem of desiccation are discussed.