The present disclosure relates to a segmental joint of cast-in-place UHPC bridge beam, and belongs to the field of bridge structure. The joint comprises a plurality of female joints disposed at an end of a first segment and a plurality of male joints disposed at an end of a second segment, wherein each female joints and the male joints are correspondingly connected to form a tongue-and-groove connection, and each of the male joints is of a structure with big outer part and small inner part. The beam segment joint of the present disclosure not only applies to the joint connection between the segmental cast-in-place UHPC beam segments and the construction of the segmental cast-in-place UHPC beam segment, but also to joint connection of UHPC bridge deck of UHPC-steel composite beam and of full UHPC bridge deck of UHPC composite box girder with corrugated steel webs and to UHPC bridge deck construction.

The invention provides novel articles of composite materials having hollow interior channels or passageways, or otherwise being hollowed out, and formulations and methods for their manufacture and uses. These hollow core objects are suitable for a variety of applications in construction, pavements and landscaping, and infrastructure.

Provided is a cement composition that has high fluidity (for example, a 0-drop flow value of 200 mm or more) before curing and exhibits high compressive strength (for example, 320 N/mm.sup.2 or more) after curing. The cement composition includes a cement, a silica fume having a BET specific surface area of from 10 m.sup.2/g to 25 m.sup.2/g, an inorganic powder having a 50% cumulative particle size of from 0.8 m to 5 m, a fine aggregate having a maximum particle size of 1.2 mm or less, a water reducing agent, an antifoaming agent, and water. The ratio of the cement is from 55 vol % to 65 vol %, the ratio of the silica fume is from 5 vol % to 25 vol %, and the ratio of the inorganic powder is from 15 vol % to 35 vol % in the total amount of 100 vol % of the cement, the silica fume, and the inorganic powder.

The invention is the development of new and unique formulations and mixtures along with unique and improved manufacturing processes for a clear departure for all manufacturing processes in which calcium silicate or cement-based formulations and mixtures are commonly utilized in manufacturing fire liner panel systems of the prior art. The invention serves the current fire protection/training industry with new and unique formulations and mixtures along with improved manufacturing processes that produce a fire liner panels system with enhanced performance characteristics which are unparalleled teachings not present, nor found in any of the prior art.

Provided is a cement composition that has high fluidity (for example, a 0-drop flow value of 200 mm or more) before curing and exhibits high compressive strength (for example, 320 N/mm.sup.2 or more) after curing. The cement composition includes a cement, a silica fume having a BET specific surface area of from 10 m.sup.2/g to 25 m.sup.2/g, an inorganic powder having a 50% cumulative particle size of from 0.8 m to 5 m, a fine aggregate having a maximum particle size of 1.2 mm or less, a water reducing agent, an antifoaming agent, and water. The ratio of the cement is from 55 vol % to 65 vol %, the ratio of the silica fume is from 5 vol % to 25 vol %, and the ratio of the inorganic powder is from 15 vol % to 35 vol % in the total amount of 100 vol % of the cement, the silica fume, and the inorganic powder.

The invention encompasses methods to control the curing of a CO.sub.2 Composite Material (CCM) and processes that use such equipment to cure the CCM. The method provides a way to compute the expected water distribution in an uncured porous concrete product based on a set of environmental conditions on.

A method for curing cementitious articles includes flowing dry steam and carbon dioxide (CO.sub.2) simultaneously into a curing chamber containing a cementitious article. A relative humidity within the curing chamber may be between about 50% and about 70% and a temperature within the curing chamber may be between about 50 C. and about 70 C. A dry steam and CO.sub.2 mixture with a CO.sub.2 concentration between 2.5 vol % and 40 vol % is provided in the curing chamber and the cementitious article is cured for a duration between about 4 hours and 16 hours. Cementitious products cured with the method may have a CO.sub.2 uptake of greater than 15 wt % and a mechanical strength at least 10% greater than a cementitious product cured only in dry steam or CO.sub.2.

Disclosed is a sand aerated concrete panel pre-embedded with a wire box and a wire conduit and its preparation method. The concrete panel includes a sand aerated concrete panel, a steel bar mesh cage, a wire box and a wire conduit. The steel bar mesh cage includes a plurality of longitudinal main steel bars, a plurality of transverse auxiliary steel bars and a plurality of connecting iron pieces; the wire box and the wire conduit are fixed on the steel bar mesh cage; and the steel bar mesh cage, the wire box and the wire conduit are poured in the sand aerated concrete panel. The disclosure solves the problems of complicated procedures, high cost, environmental pollution caused by dust and noise in the prior art, avoids the potential quality hazards of the panels and wall structures caused by on-site slotting, reduces labor force, intensity and cost.

A method of curing a concrete product having a cavity is described and includes positioning the concrete product on a base, sealing an opening to the cavity using a cover plate, introducing carbon dioxide (CO2) gas into the cavity to execute carbonation of the concrete product, and, in response to the concrete product attaining a target specification, unsealing the opening. A system for curing a precast concrete product is also described.

A building product is made from granular material and a binder that includes steel slag. A process for making the building product includes combining the granular material and the binder and then curing the combined granular material and binder with carbon dioxide. A building material includes a mixture of steel slag and a silica-rich material. The steel slag and silica-rich material is treated by heating. The silica-rich material may be waste glass and/or fly ash. A process for making the building material includes mixing the steel slag and silica-rich material and further heating the mixture.