Abstract: A settable composition which can be applied by spraying to form a coating on a surface such as the walls of a mine comprises (i) a cementitious composition comprising the following components: (a) from 25 to 95% of calcium aluminate, (b) from 0 to 10% of lien and (c) from 0 to 50% of calcium sulphate, and where the sum of (b) and (c) is at least 5% the % being by weight based on the combined weight of (a), (b) and (c) and where the proportions of the components are such that the composition on hydration is capable of absorbing at least its own weight of water and (ii) an aqueous emulsion of an organic polymer, the amount of (ii) in relation to (i) being such as to provide a weight ratio of polymer, expressed as solids, to combined weight of (a), (b) and (c) of from 0.5:1 to 10:1, preferably 1:1 to 2.5:1 or (iii) a dispersible organic polymer and where the amount of dispersible polymer is such as to give a weight ratio of polymer to combined weight of (a), (b) and (c) o from 0.5:1 to 10:1, preferably 1:1 to 2.

Abstract: A settable composition suitable for coating surfaces; e.g., walls of a mine comprises (i) a cementitious composition comprising the following components: (a) at least 25% preferably at least 40% of a reactive cement having a C to A or (A+X) ratio of greater than 1:1 preferably greater than 1.2:1, where X is S* or S or F (b) from 0 to 10% of lime and (c) from 5 to 70% preferably 10 to 40% of calcium sulphate, and where the sum of (b) and (c) is at least 15% the % being by weight based on the combined weight of (a), (b) and (c) and where the proportions of the components are such that the composition on hydration is capable of absorbing at least its own weight of water and (ii) an aqueous emulsion of an organic polymer, the amount of (ii) in relation to (i) being such as to provide a weight ratio of polymer solids to combined weight of (a), (b) and (c) of from 0.5:1 to 10:1, preferably 0.

Abstract: A settable composition which can be applied by spraying to form a coating on a surface such as the walls of a mine comprises (i) a cementitious composition comprising the following components: (a) from 25 to 95% of calcium aluminate, (b) from 0 to 10% of lime and (c) from 0 to 50% of calcium sulphate, and where the sum of (b) and (c) is at least 5% the % being by weight based on the combined weight of (a), (b) and (c) and where the proportions of the components are such that the composition on hydration is capable of absorbing at least its own weight of water and (ii) an aqueous emulsion of an organic polymer, the amount of (ii) in relation to (i) being such as to provide a weight ratio of polymer, expressed as solids, to combined weight of (a), (b) and (c) of from 0.5:1 to 10:1, preferably 1:1 to 2.5:1 or (iii) a dispersible organic polymer and where the amount of dispersible polymer is such as to give a weight ratio of polymer to combined weight of (a), (b) and (c) of from 0.

Abstract: A settable composition suitable for coating surfaces eg walls of a mine comprises (i) a cementitious composition comprising the following components:(a) at least 25% preferably at least 40% of a reactive cement having a C to A or (A+X) ratio of greater than 1:1 preferably greater than 1.2:1 where X is S* or S or F (b) from 0 to 10% of lime and (c) from 5 to 70% preferably 10 to 40% of calcium sulphate, and where the sum of (b) and (c) is at least 15% the % being by weight based on the combined weight of (a), (b) and (c) and where the proportions of the components are such that the composition on hydration is capable of absorbing at least its own weight of water and (ii) an aqueous emulsion of an organic polymer, the amount of (ii) in relation to (i) being such as to provide a weight ratio of polymer solids to combined weight of (a), (b)) and (c) of from 0.5:1 to 10:1, preferably 0.