The invention relates to a multilayer synthetic-mineral protective- levelling and/or sealing lining used in construction, particularly for protecting slopes from erosion, levelling and hardening of subsoils for all types of works and materials, and/or as a seal impervious to liquid in various types of facilities.

Patent document US 8,287,982 B2 discloses a spacer fabric with a tightly knitted bottom layer, very loosely knitted top layer and pile yarns running through the space between the top and bottom layer. A hardening material, particularly powder containing cement, is introduced into the space between the top and bottom external layer, and it may be hardened by adding a liquid. Before hardening, the fabric is flexible and may be shaped; however, after hardening of the material in the fabric's space, the fabric becomes rigid and may be used as a structural component in many situations. Additionally, the fabric may be protected with a sealant on the side with larger pores, while the other side with smaller pores allows for penetration of the liquid to harden the material.

Patent document US 2015/352804 Al discloses a composite textile that can become rigid or semi-rigid by e. g., applying a liquid is provided. The composite can include a high loft non-woven layer having a first face and a second face and a midpoint between the first face and the second face. The high loft non-woven layer includes bulking fibers crossing the midpoint plane that form a tangential line at the midpoint plane that is at non-zero angle.

The purpose of the invention is to develop a lining which protects covered surfaces from erosion, having the form of a rigid cover which may be wound up into a roll before stiffening.

A multilayer synthetic-mineral protective-levelling and/or sealing lining comprising a bottom layer made of a synthetic material, a top layer made of a synthetic material, according to the invention is characterised in that the bottom layer is a base layer made of a synthetic woven or unwoven fabric, while the top layer is made of a synthetic unwoven fabric, and there is at least one intermediate layer between the said layers, comprising a mineral material, wherein the said at least one intermediate layer comprises powdered cement, and the bottom base layer is connected with the top layer by stitches made over the entire surfaces of the said layers, providing a mutual pressing of all lining layers, and a layer of an impermeable plastic is affixed to the external surface of the bottom base layer.

Preferably, at least one intermediate layer comprises a swellable mineral material, preferably sodium bentonite, with a separating base layer placed between the intermediate layers, made of a synthetic woven or unwoven fabric.

Preferably, the said intermediate layer comprises a swellable mineral material placed between the bottom base layer and the separating base layer, and the intermediate layer comprising powdered cement is placed between the separating base layer and the top layer.

Preferably, the layer of an impermeable plastic is thermally connected with the bottom base layer, and said layer is preferably constituted by a double- layer polymer film, with layers preferably having different melting temperatures, the film layer adjacent to the bottom base layer having a lower melting temperature than the other film layer.

The multilayer lining according to the invention has physico- chemical and strength parameters sufficient to consider it a proper material for use on covered objects in locations requiring fast and resistant protective cover in a permanent manner after its hydration. The lining according to the invention completely or partially replaces the lean concrete layer required in the preparation of subsoils for the facilities being built. It also enables replacement of the troublesome covering by conventional methods of concreting tank interiors, channels and ditches or lining them with concrete slabs. An additional intermediate layer in the form of bentonite actively protects the coating from leaks, ensuring the lining's impermeability and filling possible cracks formed in the main concrete layer obtained from the cement used in the intermediate layer with bentonite gel. The layer applied in the form of a plastic film additionally protects the lining from leaks, and the two intermediate layers located above (the bentonite layer and the concrete layer) provide protection from mechanical damage to the film.

Further benefits and advantages of the present invention will become apparent after a careful reading of the detailed description with appropriate reference to the accompanying drawings in which Fig. l and Fig.2 show a cross section of the multilayer synthetic-mineral protective-levelling and/or sealing lining.

In one embodiment of the invention presenting on Fig. l , a multilayer synthetic-mineral protective-levelling and/or sealing lining comprises a bottom base layer 1 made of a synthetic woven or unwoven fabric and a top layer 2 made of a weakly stitched synthetic unwoven fabric. Between these layers, one intermediate layer 3a comprising powdered rapid-hardening cement after being infused with a proper amount of water or liquid, is located. The bottom base layer 1 is connected mechanically with the top layer 2 by stitches 6 (by needling) made over the entire surfaces of the said layers, providing a mutual pressing of all lining layers and pulling the fibres of the top layer 2 beyond the external surface of the bottom base layer 1. Additionally, a layer 5 in the form of a double low-melting polymer film, constituting an additional impermeable layer of the lining, is affixed thermally to the fibres of the top layer 2 pulled-through beyond the external surface of the bottom base layer 1 and over the entire external surface of the bottom base layer 1. The layers of the double polymer film have different melting temperatures, the film layer adjacent to the bottom base layer 1 having a lower melting temperature than the other film layer.

In the second embodiment of the invention presenting on Fig.2, the lining described in the first embodiment comprises a second intermediate layer 3b containing powdered sodium bentonite. Between the intermediate layer 3 a comprising powdered cement and the intermediate layer 3 b comprising sodium bentonite, there is a separating base layer 4, made of a synthetic woven or unwoven fabric, the layer 3b of powdered sodium bentonite being placed between the bottom base layer 1 and the separating base layer 4, and the intermediate layer 3 a comprising powdered cement being placed between the separating base layer 4 and the top layer 2.

The bottom base layer 1 is connected mechanically with the top layer 2 by stitches 6 (by needling) made over the entire surfaces of the said layers, providing a mutual pressing of all lining layers and pulling the fibres of the top layer 2 beyond the external surface of the bottom base layer 1.

Additionally a layer 5 in the form of a double low-melting polymer film, constituting an additional impermeable layer of the lining, is affixed thermally to the fibres of the top layer 2 pulled-through beyond the external surface of the bottom base layer 1 and over the entire external surface of the bottom base layer 1. The layers of the double polymer film have different melting temperatures, the film layer adjacent to the bottom base layer 1 having a lower melting temperature than the other film layer. In both of the abovementioned cases, the surface weight of the unwoven or woven fabric, from which the base layers 1 , 4 are made, is 80 g/m ² to 300 g/m ² , and the surface weight of the unwoven fabric, from which the top layer 2 is made, is more than 100 g/m ² to 300 g/m ² .

Preparation of the multilayer lining consists in a sequential placement of the layers one over another, starting from the bottom base layer 1 , and then stitching all layers over the entire surface by needling, providing a mutual pressing of all lining layers. After stitching, an additional layer 5 is affixed in the form of a double impermeable plastic film, particularly polymer film, in a process comprising heating and pressing the film to the surface being connected with it.

Before being infused with water and hardening, the lining may be rolled and delivered to the place of use in the form of a roll, and then unrolled, fitting it to the object or ground surface being covered. Next, the lining may be infused with water.

Hardening of the lining is being obtained by infusing it with a proper amount of water or other liquid, which causes the setting process of the cement in the intermediate layer.

After being infused with water or other liquid, the lining forms a solid concrete crust.