EVA Structure of ethylene vinyl acetate waterproof sheet attaching to non-oven fabrics by a heat fuse

摘要

The present invention provides an EVA sheet structure of an integrated waterproof sheet, in which an integrated waterproof sheet is formed by thermally bonding an EVA sheet having drainage protrusions and non-woven fabric such that underground water at a stable stage of excavation is normally drained to a lower part of an arch, without remaining, by the drainage protrusions while being adapted to drainage of the underground at an initial stage of the excavation. Specifically, firstly, the present invention forms a central thermal bonded surface section long in a longitudinal direction at the center in the short width direction of the EVA sheet and forms multiple thermal bonded surface sections symmetrically on both sides from the central thermal bonded surface section to be spaced at regular intervals to increase the attachment area, thereby having an attachment strength increase function in accordance with the increase of the attachment area in order to solve a problem of separation from the non-woven fabric caused by spot bonding of the conventional integrated waterproof sheet. Secondly, the present invention fills drainage protrusion cells (cf) in a gap between the thermal bonded sections wherein the gap is not thermally bonded, whereas unit set cells (U) are formed with longitudinal and traverse drains (B, D) surrounding four sides of the drainage protrusion cells (cf) and micro inducing water path recesses (b) are formed between the drainage protrusions of the drainage protrusion cells (cf) to increase water connection cross section through multiple drainage paths, thereby having a drainage function much more added to the EVA sheet structure.