Drainage material and drainage core for a drainage system
US4815892A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 21, 1988 |
| Grant date | Mar 28, 1989 |
| Priority date | — |
| Expiry date | Jan 21, 2008 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE02D31/02
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A drainage system having an at least 2.5 mm thick bi-planar mesh structure drainage core and a filter material against one face and a filter material or impervious member against the other face. The drainage core has generally parallel main strands interconnected by generally parallel subsidiary strands. The main strands are at least twice as tall as the subsidiary strands. The outer faces of the subsidiary strands are coplanar with, and form, one face of the drainage core. The ratio of the free cross-sectional area of each main flow channel to the free cross-sectional area of each subsidiary flow channel, if any, is at least 2.5:1. The drainage core can resist pressures of at least 400 kPa, exhibits a flow fall-off of not more than 20% under an external pressure normal to the faces of 400 kPa.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.