A prefabricated composite concrete element for use in a corrosive sewer environment. The concrete element has a hollow reinforced cast concrete portion with at least one end having connection details, a premolded corrosion resistant inner plastic liner. The plastic liner lines an interior of the hollow concrete element and the connection details to provide abutting liner faces in an assembled joint to limit exposure through said joint of said concrete portion to corrosive materials arising in said sewer environment. At least two prefabricated composite concrete elements may be assembled end to end at a joint to form a concrete sewer system. Also disclosed are a method of prefabricating such a composite concrete element.

The present invention relates to a process of fabricating a multi-layer composite structure by 3D printing, said composite structure comprises at least one cured mortar layer formed by curing of a mortar composition, and at least one polyurethane layer formed by polymerization of a first polyurethane forming composition, wherein said mortar composition and said first polyurethane forming composition are dispensed individually and simultaneously via adjacent printing nozzles. The mortar composition is optionally modified by a second polyurethane forming composition.

A manhole base assembly and a method for making the same employ a non-cylindrical, low-volume concrete base that is fully lined to protect the concrete against chemical and physical attack while in service. This lined concrete manhole base assembly may be readily produced using a modular manhole form assembly which can be configured for a wide variety of geometrical configurations compatible with, e.g., varying pipe angles, elevations and sizes. The form assembly is configurable to provide any desired angle and elevation for the pipe apertures to interface with various underground systems, and can be formed on-site to facilitate compatibility with existing structures. The assembly provides for flexible, modular construction of a wide variety of lined manhole base assemblies at minimal cost, reduced concrete consumption and reduced operational complexity. The modular nature of the production form assembly also facilitates reduced inventory requirements when various manhole base assembly geometries are needed.

A prefabricated composite concrete element for use in a corrosive sewer environment. The concrete element has a hollow reinforced cast concrete portion with at least one end having connection details, a premolded corrosion resistant inner plastic liner. The plastic liner lines an interior of the hollow concrete element and the connection details to provide abutting liner faces in an assembled joint to limit exposure through said joint of said concrete portion to corrosive materials arising in said sewer environment. At least two prefabricated composite concrete elements may be assembled end to end at a joint to form a concrete sewer system. Also disclosed are a method of prefabricating such a composite concrete element.

Provided are a dispersion for a silicon carbide sintered body having a small environmental load, high dispersibility, and excellent temporal stability, and a manufacturing method thereof. The dispersion is a dispersion for a silicon carbide sintered body, containing: silicon carbide particles; boron nitride particles; a resin having a hydroxyl group; and water, wherein the dispersion has a pH at 25° C. of less than or equal to 7.0, and the silicon carbide particles and the boron nitride particles have charges of the same sign. The dispersion is manufactured by a manufacturing method of a dispersion for a silicon carbide sintered body, including a mixing step of mixing a water dispersion containing silicon carbide particles, a water dispersion containing boron nitride particles, and an aqueous solution containing a resin having a hydroxyl group.

Provided are cementitious panels that include a cementitious core material and a plurality of sheets of facing material surrounding the cementitious core material, in which at least one of the plurality of sheets of facing material includes a polymeric-film. The polymeric film may include a thermoplastic composition that has a polymeric matrix including one or more polymeric materials. Additionally, the thermoplastic composition may optionally include a filler material. Additionally, provided are methods of manufacturing such cementitious panels.

The present invention provides structure protection sheets which can not only dramatically reduce a construction period to place protective layers on surfaces of structures such as concrete but also protect structures for a long time. The present invention relates to a structure protection sheet, including: a polymer cement layer on a side facing a structure; and a resin layer on the polymer cement layer, the structure protection sheet having a thickness distribution of not more than ±100 μm.

Example embodiments of the described technology provide a prefabricated building panel. The prefabricated building panel may comprise an insulative core having first and second opposing faces. The prefabricated building panel may also comprise a cementitious layer encapsulating the insulative core. The cementitious layer may increase one or more performance characteristics of the panel.

Provided are a dispersion for a silicon carbide sintered body having a small environmental load, high dispersibility, and excellent temporal stability, and a manufacturing method thereof.

The dispersion is a dispersion for a silicon carbide sintered body, containing: silicon carbide particles; boron nitride particles; a resin having a hydroxyl group; and water, wherein the dispersion has a pH at 25° C. of less than or equal to 7.0, and the silicon carbide particles and the boron nitride particles have charges of the same sign. The dispersion is manufactured by a manufacturing method of a dispersion for a silicon carbide sintered body, including a mixing step of mixing a water dispersion containing silicon carbide particles, a water dispersion containing boron nitride particles, and an aqueous solution containing a resin having a hydroxyl group.

Provided are cementitious panels that include a cementitious core material and a plurality of sheets of facing material surrounding the cementitious core material, in which at least one of the plurality of sheets of facing material includes a polymeric-film. The polymeric film may include a thermoplastic composition that has a polymeric matrix including one or more polymeric materials. Additionally, the thermoplastic composition may optionally include a filler material. Additionally, provided are methods of manufacturing such cementitious panels.