Fast-setting Portland cement compositions for filling voids, such as mine shafts and excavated utility trenches, are described. The Portland cement compositions set quickly and are useful when traditional slow setting compositions are less desirable. The acceleration of the set time results from the addition of dry calcium chloride to the Portland cement composition. The compositions consist of Portland cement, dry calcium chloride, water and sometimes preformed cellular foam. Some compositions can include also include fly ash. The compositions may have a compressive strength of between 0 psi and 30 psi after 4 hours, a compressive strength of between 30 psi and 120 psi after 24 hours, a compressive strength of between 200 psi and 500 psi after 28 days, a penetration resistance of between 0.1 tsf and 5 tsf after 10 hours, a penetration resistance of between 0.8 tsf and 10 tsf after 24 hours, and a removability modulus of between 0.2 and 1.0 after 28 days. Also disclosed are methods of filling a void with fast-setting Portland cement.

A process of fabricating a static structure including an interior volume that includes the steps of mixing coal combustible residual (CCR) with structural reinforcing materials to form a construction material and utilizing the construction material to fabricate exterior enclosure-forming components of the static structure. The enclosure-forming components are sufficiently reinforced, enhanced and/or thick to provide protection against exterior forces directed against the structure.

Fast-setting flowable fill compositions for filling ground trenches are described. The compositions set quickly but retain a low strength psi at 28 days. The compositions also reduce bleed water on the surface of the fast-setting flowable fill and therefor enable quicker application of surface repair material, e.g., pavement patches, to the trench. The compositions consist of aggregate, Portland cement, accelerant, water and sometimes air. The compositions may have a compressive strength of between 5 psi and 60 psi after 2 hours, a compressive strength of between 10 psi and 100 psi after 4 hours, a compressive strength of between 75 psi and 500 psi after 28 days, a penetration resistance of between 1.5 tsf and 75 tsf after 2 hours, a penetration resistance of between 4.5 tsf and 200 tsf after 4 hours, and a shrinkage of less than 2% as measured by ASTM C490. Also disclosed are methods of filling a trench with fast-setting flowable fill.

A system and associated methods for processing unhardened concrete are disclosed. It at least one embodiment, the system for processing unhardened concrete includes a means to estimate a quantity of returned concrete; a foam adder to add foam to the quantity of returned concrete; a mixer to mix the added foam and returned concrete together to create treated concrete; a discharger to discharge the treated concrete; a discharge area configured in which to allow the treated concrete to set and harden; a converter to convert the hardened treated concrete into a particulate or aggregate form; and a user to determine the specific utilization of the particulate or aggregate form loose material.

A full-length screen pipe hole protection device and method with pressurized hole packing in a soft coal seam relates to the field of gas drainage technologies. The device includes a grouting system, a drainage system and a hole fixing system. The grouting system injects a pressurized sealing material into a borehole through a pressure pump to increase a sealing effect of the borehole. The drainage system drains gas in the middle of air holes on metal baffle plates and hole fixing screen pipes through a drainage pipe to increase flowability of gas. The hole fixing system is inside the borehole and fixed with the metal baffle plates, and the hole fixing screen pipes are fixedly connected with each other through fitting mouths and fitting buckles. The device is fixedly mounted in the gas drainage borehole. After hole packing, the drainage pipe is connected with a drainage pump to drain gas.

A fire-resistant two-component mortar system contains a curable aqueous-phase aluminous cement component A and an initiator component B in aqueous-phase for initiating the curing process. Component A further contains at least one blocking agent selected from phosphoric acid, metaphosphoric acid, phosphorous acid and phosphonic acids, at least one plasticizer, and water. Component B contains an initiator, at least one retarder, at least one mineral filler, and water. A fire-resistant two-component system, which is ready-for-use, can be used for a fire-resistant chemical fastening of anchors and post-installed reinforcing bars in mineral surfaces, such as structures made of brickwork, concrete, pervious concrete or natural stone.

The present invention relates to a composition for manufacturing methylene malonate cementitious hybrid systems. Particularly, the invention relates to a composition comprising at least one methylene malonate monomer (A), at least one methylene malonate polymer (B), at least one acidic stabilizer (C), and cement (D), to the preparation thereof, and to the use of the composition in construction, particularly as a surface protection material, a structural consolidation material or as a material used in underground constructions.

Techniques of forming a foamed insulation material from gypsum waste are disclosed herein. One example technique includes mechanically comminuting the gypsum waste from an original size into particles of gypsum at a target size smaller than the original size and mixing the particles of the gypsum with a binder to form a mixture of particles and binder. The binder is configured to bind the particles of gypsum upon hydration. The example technique can further include performing air entrainment on the mixture until a foam is formed from the mixture having the particles of gypsum and binder. The foam has water that causes the binder to bind the particles of gypsum. The example technique can then include removing moisture from the mixture with the formed foam to form a foamed insulation material from the particles of gypsum.

Herein discloses a method of carbonating reactive magnesia cement, which includes: (i) providing an aqueous suspension including a carbon dioxide-producing bacteria; (ii) mixing the aqueous suspension with a precursor which the carbon dioxide-producing bacteria generates carbon dioxide from for a duration to form an aqueous mixture sufficient for substantially carbonating the reactive magnesia cement; (iii) mixing the aqueous mixture with the reactive magnesia cement to form a blend; wherein a nutrient is provided in the aqueous suspension of step (i) or in the reactive magnesia cement of step (iii) to sustain the carbon dioxide-producing bacteria in the reactive magnesia cement; and (iv) curing the blend to carbonate the reactive magnesia cement. A reactive magnesia cement composite formed by the method is also disclosed.

An inorganic mortar system for a chemical fastening of an anchor in a mineral surface includes calcium sulfate, a component A, and a component B for initiating a curing process. Component A includes water, aluminous cement, at least one plasticizer, and at least one blocking agent selected from phosphoric acid, metaphosphoric acid, phosphorous acid, and a phosphonic acid. Component B includes an initiator, at least one retarder, at least one mineral filler, and water. Component A is also a curable composition.