A concrete comprises in relative parts by weight: 100 of Portland cement; 0.25 to 9 of a defoamer; 0.001 to 6 of a surfactant; 0 to 230 of coarse gravel and/or fine gravel and/or shear enhancers; 0 to 85 of sand; 0 to 60 of a particulate pozzolanic or non-pozzolanic material or a mixture thereof having a mean particle size less than 15 micrometers; 0 to 80 of a particulate pozzolanic or non-pozzolanic material or a mixture thereof having a mean particle size between 15 to 88 micrometers; 0.3 to 18 of a water-reducing superplasticizer; 0 to 14 of polyethylene fibers; and 5 to 40 of water. An air mixing process using a tightly sealed mixing tool is used to thoroughly mix the constituents of the concrete before adding the water for curing. By adjusting relative parts in the composition, concretes of high and ultrahigh performance can be achieved efficiently.

The disclosure relates to methods of making asphalt concrete mixtures including reclaimed asphalt pavement (RAP). Variability in the fraction of binder that occurs in RAP that is able to melt and mix with virgin binder included in the concrete mixture previously made it difficult to select an appropriate amount of virgin binder. Methods described herein permit an asphalt concrete mix designer to determine the amount of virgin binder that can be combined with RAP and virgin aggregate in order to satisfy the minimum effective binder content of a job mix formula for such a concrete mix. The subject matter described herein thus permits more efficient use of RAP and permits use of RAP in higher amounts in asphalt concrete mixtures.

Truck mixer with safety device, comprising a drum rotatable around an axis of rotation by means of rotation devices, which comprise a first drive member of the electric type suitable to make said drum rotate, during normal use, and a second drive member that functions as a safety device, able to be selectively actuated in a condition of non-usability, even temporary, of said first drive member, and also suitable to make the drum rotate.

A concrete mixer truck comprises a vehicle provided with a heat engine and a concrete mixer having a rotating drum and an auxiliary device provided with a unit for generating electric energy that selectively feeds an electric motor connected to the rotating drum. The electric energy generating unit comprises at least an alternator selectively connectable to the heat engine and to a movement unit of the vehicle by means of a gearbox and a power take-off positioned between the clutch of the vehicle and the gearbox. The alternator is configured to convert mechanical energy into alternate electric energy and vice versa. The electric energy generating unit also comprises at least one accumulator and reversible conversion means of electric energy, connected to the accumulator and to the alternator in order to selectively take continuous electric energy from the former and supply alternate electric energy to the latter, to move the drive wheels of said movement unit, or to convert the alternate electric energy produced by the alternator into continuous electric energy to be transferred to the accumulator.

The present invention relates to a process for producing a foam ceramic comprising the steps: producing an aqueous suspension of a first mineral raw material; foaming the suspension with air while adding a foaming agent and a binder to form a light foam; mixing the light foam with a powder or slip of a second ceramic raw material to form a heavy foam; pouring the heavy foam into a mold; drying the molded heavy foam in the mold to form a solid foam; and firing the solid foam in the mold to form the foam ceramic.

An extruder includes a receptacle for containing material to be extruded. The extruder further includes a dispersion blade positioned within the receptacle and a nozzle secured to the receptacle. The nozzle defines a first opening positioned within an interior of the receptacle, defines a second opening positioned outside of the receptacle and defines a channel which extends from the first opening through the nozzle to the second opening defining a flow path which extends from the first opening, through the channel and to the second opening. The nozzle extends through a wall of the receptacle and into the interior of the receptacle such that the first opening is positioned spaced apart from the wall.

Mixing systems that include a mixer housing and one or more disk assemblies for mixing and processing materials is disclosed. The disks rotate to mix an additive into the material and to carry agglomerated solids toward a discharge of the mixing system. The disks may have a plurality of fingers or lobes which extend from a central portion of the disks.

A method of preparing high strength coral concrete, wherein the high strength coral concrete is prepared from raw materials of the following parts by mass: 25˜63 parts of cementing materials, 45˜58 parts of coral aggregate, 10˜16 parts of mixing water and water reducer 2˜5% the weight of the cementing materials; the weighed coral aggregate, mixing water, water reducer and 55˜85% of the cementing materials are stirred in an agitator for 10˜15 minutes; the rest of cementing materials are added in batches before initial setting and stirred; then poured and removed from the mould after 24 hours, cured in mixing water at normal temperature for 28 days, to get the high strength coral concrete.

A method of treating recycled concrete aggregates (RCA) that includes constructing a chamber configured to form a hermetic seal, loading the RCA into the chamber, hermetically sealing the chamber, pressurizing the interior of the chamber with carbon dioxide gas, monitoring a pressure and a relative humidity in the interior of the chamber, and controlling the pressure and the relative humidity until a predetermined condition is met.

Methods for modifying a recycled fine powder of concrete and uses thereof. A method for modifying a recycled fine powder can include: crushing a collected waste concrete block with a crusher, grinding with a ball mill, and passing through a 100-mesh sieve, to obtain a recycled fine powder with d50 of 13.5 μm; placing the obtained recycled fine powder in a dry environment at a high temperature, drying, then taking out, and cooling to room temperature; preparing tannic acid solutions with different concentrations, mixing the cooled recycled fine powder with the prepared tannic acid solutions, and continuously stirring by a glass rod.