| 摘要 |
<p>DEVICE FOR LAYING AND STRETCHING WATERPROOF COVERING SHEETS Device for laying and stretching covering sheets over surfaces to be protected, the device comprising a first channel element, having a bottom and lateral walls, a second channel element having a bottom and lateral walls, smaller in depth than those of the former; first fastening means for securing one of said channel elements with its bottom facing towards the surface to be covered. Second fastening means being also provided in order to secure the other of said channel elements in position over the first one and with its lateral edges facing towards the bottom of the first channel element securing and tensioning the covering sheets interposed between the aforementioned channel element. The advance in the art is in the provision of sufficient space within the device for excessive material. This is achieved, firstly, by providing the two channel-shaped members to be of such size that the smaller one can freely move within the larger one and can be completely received therein. Furthermore, the fact that both elements are channel-shaped provide further space for suitable accumulation of the material gathered during the stretching operation. Thus, the arrangement is particularly suitable for use in covering large surfaces such as building structures, dam walls etc.</p> |
