| 摘要 |
In order to improve a plastic waterproofing sheet for installations for the storing of substances at risk from water, in particular for refuse landfill sites, to the extent that, inter alia, not only can they be joined together to form large-area, homogeneous landfill waterproofing means, but that also a greater imperviousness can be achieved than with plastic waterproofing sheets used hitherto for this purpose, it is proposed to provide a multilayered sheet which comprises two homogeneous sheets (1, 2) of plastic which are identical to each other and are arranged on the upper side and underside of the multilayered sheet, which can be welded well, has a high resistance to weather and to ageing amd also a high resistance to UV rays, a high tensile strength and extensibility as well as a high chemical resistance, and comprises at least one sheet (3, 7, 8) of plastic which is arranged congruently between the abovementioned sheets (1 and 2) and has in comparison with the outer sheets (1, 2) a higher vapour impermeability and at least approximately the same mechanical properties as the plastic of the two outer sheets (1 and 2). |
