Disclosed are a rock similar material satisfying a water-induced strength degradation characteristic and a preparation method and use thereof. The rock similar material satisfying the water-induced strength degradation characteristic includes an aggregate, a cementing material, and an additive, where the aggregate includes quartz sand, barite powder, and bentonite, and the cementing material includes cement and gypsum.

Methods for producing construction material utilizing loose pieces of aggregate (30), enzyme producing bacteria, an amount of urea and an amount of calcium ions. A first solution is prepared which includes urease which is formed by enzyme producing bacteria. A second solution is prepared which includes urea and calcium ions. The first and second solutions are added to the loose aggregate (30). The calcium ions contribute to the formation of calcium carbonate wherein the calcium carbonate fills and bonds between at least some of the gaps between the loose pieces of aggregate forming a solid construction material (92).

Methods for producing construction material utilizing loose pieces of aggregate (30), enzyme producing bacteria, an amount of urea and an amount of calcium ions. A first solution is prepared which includes urease which is formed by enzyme producing bacteria. A second solution is prepared which includes urea and calcium ions. The first and second solutions are added to the loose aggregate (30). The calcium ions contribute to the formation of calcium carbonate wherein the calcium carbonate fills and bonds between at least some of the gaps between the loose pieces of aggregate forming a solid construction material (92).

The present invention is directed to a biopolymer cement additive, a biopolymer cement composition containing the additive, the use of the additive for the production of, mortar or concrete and a process for the preparation of concrete or mortar implementing the biopolymer cement additive.

The present invention is directed to a biopolymer cement additive, a biopolymer cement composition containing the additive, the use of the additive for the production of, mortar or concrete and a process for the preparation of concrete or mortar implementing the biopolymer cement additive.

The invention relates to a self-setting porous cement foam (2) comprising a protein foam as the structuring agent, the cement foam (2) having pores when set, and the cement foam has a water absorption coefficient of between 0.5 and 7 kg/(m.sup.2.Math.h0.5).

The invention relates to a self-setting porous cement foam (2) comprising a protein foam as the structuring agent, the cement foam (2) having pores when set, and the cement foam has a water absorption coefficient of between 0.5 and 7 kg/(m.sup.2.Math.h0.5).

According to the invention, a preparation is described which contains at least one calcium compound selected from the group consisting of calcium phosphates, calcium fluorides and calcium fluorophosphates and hydroxyl derivatives and carbonate derivatives of these calcium salts, calcium hydroxides and calcium oxides precipitated using at least one protein component selected from proteins and protein hydrolysates, and at least one crosslinking agent for the protein component and/or non-set cement.

According to the invention, a preparation is described which contains at least one calcium compound selected from the group consisting of calcium phosphates, calcium fluorides and calcium fluorophosphates and hydroxyl derivatives and carbonate derivatives of these calcium salts, calcium hydroxides and calcium oxides precipitated using at least one protein component selected from proteins and protein hydrolysates, and at least one crosslinking agent for the protein component and/or non-set cement.

According to the invention, a preparation is described which contains at least one calcium compound selected from the group consisting of calcium phosphates, calcium fluorides and calcium fluorophosphates and hydroxyl derivatives and carbonate derivatives of these calcium salts, calcium hydroxides and calcium oxides precipitated using at least one protein component selected from proteins and protein hydrolysates, and at least one crosslinking agent for the protein component and/or non-set cement.