A method for improving deformability of a cementitious composite by using PET powder is provided. The aggregate in the cementitious composite is replaced with PET powder at a volume replacement ratio of 0-25%, and the value of the volume replacement ratio is not 0%. The method including following steps: mixing components of the raw materials to obtain the cementitious composite.

An efficient sound-absorbing lightweight aggregate cellular concrete, a method for preparing the same, and an application thereof. The concrete comprises: 85-95 parts by weight of low-carbon sulfur-aluminum-ferric cementitious materials, 5-15 parts by weight of supplementary cementitious material, 0.6-1.5 parts by weight of functional admixture, 20-60 parts by weight of non-sintered lightweight aggregate, 0.35-0.45 parts by weight of water, and 0.5-1.5 L of preformed foam. The non-sintered lightweight aggregate includes cementitious materials, byproduct gypsum, hydrogen peroxide, water, and expanded perlite. A multi-level pore structure is constructed from expanded perlite pores, hydrogen peroxide foaming pores, and physical foaming pores. The material exhibits a noise reduction coefficient 0.80, a bulk density500 kg/m.sup.3, and a flexural strength 1.5 MPa.

A concrete composition having an optimized formulation and suitable for 3-D printing is provided. The composition may include a hydraulic cement composition, aggregate, cement and/or aggregate by-product dust, one or more rheology modifiers, a plasticizer, fibers, and a sufficient amount of water to effect setting of the composition. Optionally the concrete composition may include a setting agent. A method for 3D printing multiple layers of the concrete composition is also provided.

The present invention provides a dry mix composition of a low-viscosity cellulose ether (50 to 750 mPa.Math.s at 1 wt. % solids, at 20 C, and a 514 s-1 shear rate, using a strain-controlled rotational rheometer (for example, ARES-G2, TA Instruments), a graded aggregate, and a hydraulic cement, or a granular wet cement composition of the cement, graded aggregate and an admixture therefor including the cellulose ether. The wet granular hydraulic cement composition behaves like asphalt compositions and has zero or near zero slump, a high lubricity and from 5 wt. % to less than 13 wt. % of water, or, preferably from greater than 5 to 10.5 wt. %, based on the total weight of the granular wet cement composition. The low-viscosity cellulose ether enables lubricity without impairing compaction and without causing air entrainment.

The invention discloses an in-situ high-strength gradient carbonized material and the preparation method thereof. The in-situ high-strength gradient carbonized material includes a core structure composed of partially calcined calcium carbonate and a shell structure; the shell structure comprises calcium hydroxide and calcium carbonate and covers the outer layer of partially calcined limestone. The invention utilizes an in-situ carbonization reaction to recycle a large amount of low-grade limestone stored or discarded in industry, providing a new technological route for solid waste disposal and resource utilization; this method not only has a green and low-carbon process but also can be widely applied in carbon dioxide capture/collection technology, as well as the preparation of new low-carbon gel materials and concrete.

A method for making a carbonated precast concrete product includes: obtaining a mixture including at least one binder material, an aggregate, and water; molding the mixture into a molded intermediate; demolding the molded intermediate to obtain a demolded intermediate, the demolded intermediate having a first water-to-binder ratio; conditioning the demolded intermediate to provide a conditioned article having a second water-to-binder ratio less than the first water-to-binder ratio of the demolded intermediate; moisturizing at least one surface of the conditioned article with an aqueous medium, thereby causing a weight gain of the conditioned article and providing a moisturized product, a first portion of the moisturized product having a third water-to-binder ratio greater than a fourth water-to-binder ratio of a remainder of the moisturized product; and curing the moisturized product with carbon dioxide to obtain the carbonated precast concrete product.