226 results about "Noise barrier" patented technology

The invention relates to a cement-matrix sound-absorption material used in road noise barriers and a preparation method thereof; the sound-absorption material is a noise barrier material which can be used in airports, high-speed railways, expressways, urban viaducts, subways and light rails; the components and weight ratios are as follows: 15.4 to 62.3 percent of Portland cement, 0.1 to 15.7 percent of mineral admixture, 18.9 to 79.9 percent of lightweight porous aggregate, 0.013 to 0.078 percent of foaming agents, 0.1 to 0.7 percent of water reducing agent and 0.4 to 2.6 percent of fiber. The sound-absorption material and the preparation method thereof have the advantages of large sound absorption coefficient, high strength, good anti-impact performance, excellent durability, fire resistance, moisture resistance, anti-corrosion and self-clean function; at the same time, the sound-absorption material is wide in sources of raw materials, convenient in preparation and processing, suitable for large-scale production, low in cost, environment-friendly and good in decorativeness.

The present invention provides a noise barrier apparatus for inhibiting external noise from causing the presence of noise in an audio chamber defined by a noise barrier device and including the user's ear canal. The noise barrier apparatus may be constituted by an in-ear noise barrier device or devices or an over-the-ear device or devices. An in-ear application of the present invention provides an in-ear-canal audio receiver comprising an in-ear-canal adapter body having a tapered ear plug portion that is inserted into the user's ear canal. The adapter body further has an opening in the plug portion, an exterior annular indent, and an inner chamber coupled to the opening of the plug portion. The inner chamber of the in-ear-canal adapter body holds a transducer assembly comprising a transducer housing and a transducer or speaker. The transducer is positioned in a passage extending through the transducer housing. A torus-shaped cushion is positioned in the annular indent of the in-ear-canal adapter body. The cushion provides comfort and establishes a good seal with the user's ear, and also provides mechanical damping to inhibit propagation of external acoustic pressure waves via the noise barrier device to an audio chamber including an interior of the noise barrier device and the user's ear canal. An over-the-ear application of the present invention provides an ear cup and has a torus-shaped cushion at an interface part thereof which bears against the side of the user's head at an area surrounding the user's ear. The cushion again provides comfort, establishes a good seal with the user's head and provides mechanical damping to inhibit propagation of external acoustic pressure waves via the noise barrier device to an audio chamber including an interior of the noise barrier device and the user's ear canal. The cushion is preferably formed of a material which is at least partially plastically deformable and provides a damping ratio greater than 0.75.

A foam barrier heat shield is provided having a layer of foam adhesively disposed between opposing first and second metallic outer layers. The foam is expanded in between the outer layers and is adhesively formed to the outer layers without the use of a separate adhesive. In addition to shielding heat, the heat shield is effective as a noise barrier and is internally damped against vibration. In a preferred embodiment, the foam is a substantially rigid polyurethane foam that is sufficiently pliant to be bent to and accommodate a particular shape and contour to which the heat shield will conform in use, and it is reversibly deformable acoustical deflections.

The invention relates to a component used in a railway, in particular to a high-speed railway noise barrier which comprises an H-shaped steel metal upright column, a precast concrete sound absorbing plate which is inserted into the H-shaped steel metal upright column, a transparent sound insulation plate installed above the precast concrete sound absorbing plate and an arc sound absorbing top part arranged at the top part of the transparent sound insulation plate. The high-speed railway noise barrier with the arc sound absorbing top part structure can efficiently absorb the noises of a high-speed railway train wheel rail, aerodynamic force of a train body and the like and prevent the noises from spreading to both sides of a line; and an insertion plate of a precast prestressed concrete unit at the lower part has no tensile stress under the load, thereby efficiently preventing the insertion plate from cracking and achieving the advantages of good anti-fatigue performance and durability, and the sound absorbing insertion plate of the prestressed concrete noise barrier has a low manufacturing cost and is convenient for installation and replacement. The high-speed railway noise barrier is suitable for places which have high requirements for noise isolation, such as urban regions, schools, hospitals, residential areas and the like.

The invention discloses a red mud porous material. In order to solve the problem of discharge of red mud, the invention adopts a synthetic technology of chemically bonded ceramics and a chemically entraining technology; and according to the invention, the porous material is prepared from red mud serving as a part of raw material of a synthetic material, as well as solid water glass, slags, coal ash, a foam stabilizer, water and a foamer. The porous material has the advantages of uniform aperture, light weight, good insulating property, low water absorption, high strength, high percentage of close area, environment-friendliness, high solid waste utilization rate and the like, and the percentage of close area of the prepared red mud porous material is over 95%, the dry density is 450-700kg/<m3>, the heat conducting coefficient can be lower than 0.13w/mk and the fire protection ability can reach 4 hours, so that the material can be widely applied to aspects such as chemical engineering, heating and heat insulating, building energy conservation, indoor sound isolation and noise barriers for expressways.

A screw compressor for acoustic resonance reduction and refrigeration systems including the screw compressor are disclosed. The screw compressor has an acoustic barrier integral with the compressor housing for use with a slide valve assembly that includes a piston connected to a slide valve. A shaft connecting the slide valve and the piston passes through an aperture in the barrier with the piston and the slide valve disposed on opposite sides of the barrier. The acoustic barrier protects the piston from discharge pulses of compressed fluid exiting the rotors of the screw compressor, thus attenuating acoustic resonance, reducing compressor noise and premature wear of the slide valve assembly and compressor housing.

The invention discloses a feed-forward active noise barrier, which comprises a passive noise barrier and a single-channel feed-forward active control system array. Each single-channel feed-forward active control system forming the array comprises a reference microphone, an error microphone, a secondary sound source and a single-channel controller. The secondary sound sources are arranged on the top of the passive noise barrier. The reference microphones are positioned on one side of a noise source and close to the top of the barrier. The error microphone is positioned on one side of an observation point and close to the top of the barrier. The controller of each single-channel feed-forward active control system is used for controlling the output of the corresponding secondary sound source so as to minimize a square value of sound pressure amplitude at the position of the corresponding error microphone, and adopts a feed-forward single-channel adaptive control algorithm. Each single-channel control system is compact, has low cost and is easy to implement. The problems of high implementing difficulty and high cost when a multi-channel control system is used are solved. Compared with the conventional feedback active noise barrier, the feed-forward active noise barrier has high system stability and a good control effect and does not have a water bed effect due to the adoption of the feed-forward control systems.

A composite membrane of wood floor diaphragm for construction of new buildings and strengthening of existing buildings to provide improved load transfer capacity and enhanced resistance to gravity and lateral loads, such as earthquake and/or wind for buildings with wood floor framing. The aforementioned composite membrane is a system, comprised of four-way interlocking mosaic end grain parquet floor attached to a plywood subfloor beneath. A floor to floor sound blocking barrier that can operate in high eighty decibel and above range may preferably be installed under the subfloor.

A traffic noise barrier system includes a longitudinal barrier and a traffic noise barrier wall. The traffic noise barrier wall is supported by the longitudinal barrier and is spaced apart from a back surface of the longitudinal barrier in a direction away from the path of traffic. Transverse beams attach the longitudinal barrier to the noise barrier wall, and a structure may be placed across the transverse beams for catching debris. Each panel in the plurality of panels may be interconnected by a cable to an adjacent panel or an upstanding post, and each post may be interconnected by a cable and/or bar. The traffic noise barrier wall is preferably positioned at a distance greater than about 18 inches from a front surface of the longitudinal barrier, and more preferably is positioned at a distance greater than about 34 inches from the front surface.

The invention relates to a plant noise barrier, which comprises a bracket upright column (4), wherein one or more plant cultivation boxes (2) are fixed on the bracket upright column (4); a plurality of sound insulation fins (3) are arranged outside the plant cultivation boxes (2); and an inclined angle is formed between each sound insulation fin (3) and the horizontal plane. The plant noise barrier has the effects of beautifying roads, preventing visual fatigue and absorbing carbon dioxide and harmful gases, can insulate sound and reduce noise by coacting the sound insulation fins and complexoverlapped plant stems and leaves, greatly reduces automobile and other noise pollution, and has better sound insulation and noise reduction effects than the traditional single noise barrier. Moreover, because each sound insulation fin has a noise reduction structure and is more effective than a wall which insulates sound and reduces noise through plants singly, the defects that the wall hardly has sound insulation and noise reduction effects in the absence of plants are overcome.

The invention provides a plate for noise barrier and a manufacturing method thereof. The plate for noise barrier comprises an aluminium honeycomb layer and a foamed aluminium layer, wherein the aluminium honeycomb layer is a hexagonal honeycombed lamella made of a thin aluminum sheet; the foamed aluminium layer is a foamed aluminium sheet which has sound-absorbing function and is provided with a plurality of air holes; the aluminium honeycomb layer is compounded with the foamed aluminium layer by an adhesive film so as to form the plate for noise barrier; moreover, the plate for noise barrier is further provided with a sound-proof material layer; and in the plate for noise barrier, one side of the aluminium honeycomb layer is compounded with the foamed aluminium layer through the adhesive film, while the other side is compounded with the sound-proof material layer through the adhesive film. The plate for noise barrier has a great noise reduction effect on a wide range of frequencies of noises, particularly the low frequency noise below 500 Hertz. The plate has the advantages of easy construction and maintenance, low cost and no dust, can be recycled, and does not burn or produce toxic gases in case of fire.

An object of the present invention is to provide a transparent noise-barrier wall which is slow to foul, easy to clean even when fouled, and capable of maintaining these effects over a long period of time. The transparent noise-barrier wall has brookite titanium dioxide substantially existing on the surface. The titanium dioxide particles preferably contain about 20% by mass or more of brookite titanium dioxide.

The invention relates to an acoustic barrier especially used for high speed railway. The acoustic barrier comprises multiple acoustic insulation components (2); the acoustic insulation components (2) comprises a plate shell (3) having an acoustic insulation liner (4) and a hollow transverse section crossing the longitudinal axis (5). The surrounding walls (6, 7, 8, 9) of the plate shell (3) consist of at least on plate (10, 11) formed by folding the hollow transverse section.

The invention discloses an acoustic design method for road noise barrier, which comprises the steps of: 1) importing a vector diagram with a Cad format for characterizing the terrains of noise barrier or grid maps with formats such as jpg, bmp, tif, and the like; 2) calibrating the imported graph to achieve the consistence of graphic proportion and actual proportion; 3) combining the actual situation to draw entities such as roads, terrains, houses, forests, grasslands, and the like based on the importing of the graph, and adopting a batch conversion function to finishing the basic work of acoustic modeling by adopting a batch conversion function if the graph is a Cad graph; 4) setting a noise prediction point at a protected sensitive point, calculating a noise value when no barrier exists, and determining an noise-reducing index of the barrier; 5) simulating the noise barrier, adjusting the height and the length of the barrier, and preliminarily calculating a geometrical dimension of the barrier which meets the requirement; and 6) re-calculating the noise-reducing effect of the barrier by combining the geometrical dimension of the sound barrier and simulating the barriers with different structures and sound absorption coefficients until the combination of the geometrical dimension, the structure and the sound absorption coefficient of the sound barrier which meets the requirement is calculated.

The invention discloses a noise barrier which comprises a plurality of columns and a plurality of wall plates which are arranged between the adjacent columns and are connected up and down, wherein a curved plate is arranged on the topmost wall plate; each wall plate is formed by arranging a noise absorbing plate between two noise insulation plates. According to the noise barrier, the noise is eliminated by using a way of insulation-absorption-insulation, and the effect is more ideal than the traditional single noise insulation or absorption effect.

The invention discloses a ribbed prestressed concrete plate type noise barrier unit plate. The noise barrier unit plate comprises a back plate and an overlapping layer, wherein the back plate is a ribbed concrete sheet made of high-strength concrete, the overlapping layer is formed by adhering a sound absorption material of light volcanic rock to one side of the back plate, the overlapping layer and the back plate are integrally poured to form an overlapping type component, the back plate is rectangular, end ribs are arranged at upper ends of long edges of the back plate respectively, prestressed wires are arranged in the end ribs at the upper and lower ends respectively, and side end ribs are arranged on two sides of short edges and equipped with constructional steel bars. According to the ribbed prestressed concrete plate type noise barrier unit plate, in the process of bearing aerodynamic force of high-speed railways, the production of fatigue stress and cracks can be avoided, the sound absorption coefficient is very high, the production cost is low, and the unit plate is adapted to the rapid development of high-speed railways.

The invention discloses a dynamic traffic flow based forecast method of noise in the peripheral zone of a long straight road. According to the method, a microcosmic moving trajectory of a vehicle in a road section is defined accurately, a vehicle source emission model is established, a noise transmission model is established simultaneously, and a complete set of noise forecasting method is obtained. The forecast method comprises steps as follows: (1), dynamic traffic flow simulation vehicle models at a forecast location are classified, and a dynamic traffic flow simulation model is established; and (2), reference radiation sound levels of different vehicle models are determined, meanwhile, traffic composition, range attenuation and noise barrier insertion loss are considered to calculate forecast sound level of the noise, and the forecast sound level is amended with consideration of surface roughness, the slope and the roadside ground type. According to the forecast method, limitation of the conventional noise forecast method is broken through on the basis that correlation research ideas of other subjects are absorbed sufficiently, and the sound level of the noise in a sensitive area can be forecast accurately.

The invention relates to a perforated glass plate and various types of structures using the same. The invention adopts a technical scheme that: the perforated glass plate is provided with small holes penetrating the perforated glass plate in the thickness direction and evenly distributed in the direction of plane, the percentage of open area is between 0.5 and 30 percent, and the small holes are round or polygonal; and the structures using the perforated glass plate comprise windows of a building using the perforated glass plate, automobile windows using the perforated glass plate, fences using the perforated glass plate, noise barriers using the perforated glass plate, totally closed structures of traffic aisles using the perforated glass plate and windshields using the perforated glass plate. The perforated glass plate has the advantages of breathability, contribution to air circulation, sound absorption effects of a perforated plate and a micro perforated plate, certain sound insulating effect and effects of shielding wind, wind pressure reduction and rainproof and theft protection effects. The structures using the perforated glass plate are suitably used for windows or glass curtain walls of buildings, automobile windows, fences, sound barriers, closing structures of a communication passage, and windshields.

A co-injection molded air intake manifold shell comprises an inner and outer skin layer separated by a sound absorbing or sound insulation core. Each skin layer is composed of a polyamide resin which, optionally, contains glass fiber reinforcement and high specific gravity fillers such as barium sulfate or tungsten. The sound insulating core is composed of a high density material having a foam structure, such as a polyamide resin. Skin layers are provided with a plurality of pockets to permit distribution of localized lumped masses at predetermined locations tailored to increase noise transmission losses. A single layer air intake manifold shell having non-uniform thickness is also provided. The thickness of the single layer air intake manifold shell is larger over preselected noise sources of larger amplitude to maximize noise attenuation for a nominal air intake manifold shell thickness.