 |
Filter Point Linings provide a permeable concrete lining for structures constructed over firm subgrades and subject to relatively low hydrostatic loads. The double-layer fabric form is joined by interwoven filter points to form a concrete lining with a deeply cobbled appearance. The spacing of the filter points determines the concrete lining's thickness and weight, while the specially designed filter points relieve hydrostatic pressure and reduce stress to the fabric form during concrete pumping. If the attenuation of hydraulic force is needed to achieve lower velocities, the high coefficient of hydraulic friction (n = 0.25 to 0.30) of Filter Point's cobbled surface provides significant advantage over smooth-faced concrete linings. |
