A lightweight building material is fabricated from paper mill sludge having about 50% water and 50% organic and inorganic materials, by taking the sludge, and drying the material in a super-heated steam bath and treating it with sodium silicate, which can be either powdered or liquid, to a selected end moisture content. Additional processing can be used at varying desired end moisture materials to create unique lightweight building aggregates from this waste source material.

A lightweight building material is fabricated from paper mill sludge having about 50% water and 50% organic and inorganic materials, by taking the sludge, and drying the material in a super-heated steam bath and treating it with sodium silicate, which can be either powdered or liquid, to a selected end moisture content. Additional processing can be used at varying desired end moisture materials to create unique lightweight building aggregates from this waste source material.

A method of pressure-pumping a ready-mixed concrete includes pouring a preceding material for pumping into a piping, then, pouring the ready-mixed concrete into the piping, and pressure-pumping the preceding material and the ready-mixed concrete, so that a lubricant layer formed of the preceding material is formed on an inner surface of the piping to thereby pressure-pump the ready-mixed concrete inside the lubricant layer made of the preceding material. The preceding material includes calcium carbonate as a main material, to which cellulose nanofibers and erythorobic acid are added, and an amount of the cellulose nanofibers is 0.005 wt % or more.

A method of pressure-pumping a ready-mixed concrete includes pouring a preceding material for pumping into a piping, then, pouring the ready-mixed concrete into the piping, and pressure-pumping the preceding material and the ready-mixed concrete, so that a lubricant layer formed of the preceding material is formed on an inner surface of the piping to thereby pressure-pump the ready-mixed concrete inside the lubricant layer made of the preceding material. The preceding material includes calcium carbonate as a main material, to which cellulose nanofibers and erythorobic acid are added, and an amount of the cellulose nanofibers is 0.005 wt % or more.

The present invention relates to fiber cement products comprising an inner core material, which inner core material is covered by at least one outer surface layer, characterized in that:said inner core material has a density of between about 0.4 and about 0.9 g/cm.sup.3 inclusive, and at least comprises cement and between 1 wt % and 70 wt % (with respect to the total dry weight of said inner core material) of a lightweight filler, andsaid at least one outer surface layer has a density of between about 0.9 and about 1.4 g/cm.sup.3 inclusive, and at least comprises fibers and cement.

A method of pressure-pumping a ready-mixed concrete includes pouring a preceding material for pumping into a piping, then, pouring the ready-mixed concrete into the piping, and pressure-pumping the preceding material and the ready-mixed concrete, so that a lubricant layer formed of the preceding material is formed on an inner surface of the piping to thereby pressure-pump the ready-mixed concrete inside the lubricant layer made of the preceding material. The preceding material includes calcium carbonate as a main material, to which cellulose nanofibers and erythorobic acid are added, and an amount of the cellulose nanofibers is 0.005 wt % or more.

A method of pressure-pumping a ready-mixed concrete includes pouring a preceding material for pumping into a piping, then, pouring the ready-mixed concrete into the piping, and pressure-pumping the preceding material and the ready-mixed concrete, so that a lubricant layer formed of the preceding material is formed on an inner surface of the piping to thereby pressure-pump the ready-mixed concrete inside the lubricant layer made of the preceding material. The preceding material includes calcium carbonate as a main material, to which cellulose nanofibers and erythorobic acid are added, and an amount of the cellulose nanofibers is 0.005 wt % or more.

The present invention relates to fiber cement products comprising an inner core material, which inner core material is covered by at least one outer surface layer, characterized in that: said inner core material has a density of between about 0.4 and about 0.9 g/cm.sup.3 inclusive, and at least comprises cement and between 1 wt % and 70 wt % (with respect to the total dry weight of said inner core material) of a lightweight filler, and said at least one outer surface layer has a density of between about 0.9 and about 1.4 g/cm.sup.3 inclusive, and at least comprises fibers and cement.

The embodiments herein are directed to dry wall waste mixtures, formed under pressure into example embodiments referred to herein as dry wall waste blocks (DWBs) and/or gypsum wallboard waste blocks (GWWBs) and tile structures. DWBs/GWWBs mixtures in particular, often incorporate a higher percentage in the composite mixtures from about 60% up to 85% of dry wall waste than other mixtures and beneficially often incorporates substantially all of the wallboard facing paper as part of the composite mixture. That is, waste processing is simplified by comingling core and paper layers in the final product. DWBs/GWWBs mixtures utilize demolition and construction waste, replacing a high percentage of Portland cement with waste-derived binder.