FLOW BEHAVIOR OF KINKED STRIP DRAINS

Due to the often expressed concern over the axial deformation of strip drains and the resulting impact on flow rate, this study has been undertaken. A laboratory experiment has been constructed, evaluated, and standardized so that strip drain flow rates can be measured in a kinked, or crimped, condition and compared to flow rates in the as received condition. This device has been evaluated using a wide range of commercially available strip drains. In general, it is seen that all drains decrease in flow rate when severely kinked, but to widely varying degrees, i.e., from 9% to 100%. Furthermore, no single physical feature of the strip drain was discovered which would aim in a visual prediction of the kinked behavior. The conclusion reached is that each strip drain type must be separately evaluated under representative in situ conditions.