Showing papers on "Screed published in 2010"

Paving machine control and method

Abstract: A control and a method of control for a machine that applies a material to a subgrade at a work site and pulls a floating screed, having a screed plate, over the top surface of the material behind the machine is useful in paving with asphalt material. The floating screed is attached to the machine by a tow arm at a tow point on said tow arm. The vertical height of the tow point is controlled by an hydraulic cylinder on said machine in response to a valve control signal applied to an hydraulic valve by a valve control drive. The screed determines the thickness of the material on the subgrade and is manipulated by adjusting the height of the tow point. A first sensor is mounted on the floating screed for sensing three-dimensional position. A second sensor for senses the pitch of said screed. A processor circuit is responsive to the first and second sensors for determining the height of the trailing edge of the screed plate and the movement of the screed over the top surface of the material. An adjusted height error value is combined with a tow point correction value produced by a three dimensional positioning system to provide for adjustment of the tow point by no more than a predetermined amount as the screed plate travels a predetermined minimum distance.

Method for laying down a pavement, a screed and a road paver

Abstract: In a method for laying down a pavement consisting of paving material with a screed of a road paver, in which a compaction unit, particularly a tamper, pre-compacts the paving material at cyclical work cycles with selectable stroke and selectable frequency while the pavement having a selectable pavement thickness) is in the process of being laid down at a selectable paving speed, at least the stroke is automatically adjustable in response to paving parameters, such as at least the paving speed and/or the pavement thickness, along a characteristic curve or in a characteristic map. In the screed the compaction unit comprises an adjusting mechanism which is operable during the ongoing paving work for adjusting the stroke of the compaction unit.

Apparatus and method for improving the control of a concrete screeding machine

Abstract: A screeding machine comprising at least one of (a) a boom speed cruise control for automatically controlling the travel speed of the screed head assembly, (b) an auto-stabilizer control that automatically adjusts the stabilizer actuators of the screeding machine to a preselected degree of extension, (c) a control for automatically controlling the lowering of the screed head assembly toward and to the concrete surface and automatically activating the auger and vibrator at a beginning of each screeding pass and automatically deactivating the auger and vibrator in response to the screed head assembly being raised away from the concrete surface at the end of a screed pass, and (d) an auto-screed mode that allows the operator to select maximum values for at least one of a boom extension speed, a boom retraction speed, a boom rotation speed and a screed head rotation speed.

Paver installation system

Abstract: The paver installation system includes a grid having a plurality of mounting holes for selective installation of spacers, a flexible edging and a screed guide rail. The screed guide rail may be selectively installed on the grid via mounting pegs mounted in select mounting holes for screeding an intermediate layer of aggregate material between the grid and the pavers to be laid thereon. The flexible edging is attached to the grid in order to set the edges of the pavement to be laid, and the flexibility thereof easily accommodates curved edges by bending to conform to the curves. The spacers are laid onto user selected mounting holes in the grid in order to serve as guides for laying pavers in a desired pavement pattern and to maintain spacing between adjacent pavers.

Cement composition for a self-leveling fluid screed, and self-leveling fluid screed thus produced

Abstract: The self-leveling fluid screed cement composition with limited shrinkage, formed by a mixture of a cement binder, a fluidizing adjuvant, granulates and water, is characterized in that the binder includes 70% to 85% by weight of Portland cement, 7% to 18% by weight of sulfo-aluminous clinker, and 6% to 14% by weight of calcium sulfate, with a calcium sulfate C$/calcium sulfo-aluminate C 4 A 3 $ molar ratio of between 5 and 7 and a water/binder ratio by weight of between 0.60 and 0.90. The self-leveling fluid screed that is thus produced has a mechanical resistance to its compression at 24 hours that is at least equal to 1 MPa, shrinkage at 7 days, measured under a relative hygrometry of 50%, less than 500 μm/m, and an endogenic expansion value that is measured at 7 days, less than 1,000 μm/m, as well as a very slight lifting of edges.

Portable vibratory laser screed with remote grade indicator and folding handles

Abstract: A portable vibratory wet concrete screed includes a blade, an exciter that is selectively driven to induce vibrations in the blade, at least one operator-manipulated handle connected to the blade and extending upwardly and rearwardly, a laser receiver mounted on the screed at a height above an upper end of the handle, and an indicator that is operatively connected to the receiver. The indicator provides a visual indication of the screed height relative to a desired grade. It is located remote from the receiver at a location which, when viewed from the perspective of a person in the vicinity of a screed operator, is at least substantially in a focal area containing the rear edge of the blade. The handle is mounted on the blade so as to be foldable from an upright, operative position in which it extends vertically and horizontally well beyond horizontal and vertical footprints occupied by a combination of the blade and the exciter to a stowed position in which it is positioned at least substantially entirely within the horizontal and vertical footprints.

Screed for road finishing machine

Abstract: In a screed with a basic screed and at least one extendable screed movable relative to the basic screed with a hydraulic cylinder and an electro-hydraulic control comprising a magnet-actuated directional control valve for at least controlling the direction of the hydraulic cylinder, the directional control valve for changing the rate of motion of the hydraulic cylinder is guided by an operator or automatically and is a proportional directional control valve (W) with proportional-electric direct actuation or proportional-electric-hydraulic pilot control The proportional directional control valve for the hydraulic cylinder is connected on the actuation side with an electro-hydraulic control of a hydraulic system of the road finishing machine

Leveling blade, vibrating screed including the blade, and kit for assembling the same

Abstract: A leveling blade for mounting onto a support bracket of a vibrating screed, and a vibrating screed including the same. The leveling blade has a substantially vertical portion for mounting onto the support bracket, as well as a substantially slanted portion and a substantially horizontal portion, which results in the leveling blade having a particular profile. The vibrating screed includes also a vibration-generating assembly, being operatively mounted onto the support bracket of the vibrating screed for imparting vibrations to the leveling blade via the support bracket so as to enable to carry out a surfacing of a substantially malleable material with the vibrating screed by passing said leveling blade provided with vibrations about said substantially malleable material. A kit is also provided for assembling such a vibrating screed.

Screed vibrator and paver

Abstract: The invention discloses a screed vibrator, which comprises an eccentric shaft, a blade, a vibration connecting seat, a vibration supporting seat and a fixed guard plate, wherein the eccentric shaft is supported on the vibration supporting seat; the upper end of the vibration connecting seat is sleeved on the eccentric shaft, while the lower end is hinged with a blade mounting seat; and the blade is arranged on the blade mounting seat, and is slidably arranged between the fixed guard plate and a bottom plate of the screed to only move up and down. The screed vibrator has the advantages of simple structure, stable running and low noise. The invention also discloses a paver, which comprises the screed provided with the screed vibrator.

Powered roller screed with curb attachment

Abstract: A powered roller screed with a curb attachment is disclosed. The powered roller screed may include a screed roller that is offset (e.g., vertically) from one or more curb rollers used by the curb attachment. In one embodiment, the amount of offset between the screed roller and each such curb roller is adjustable. Generally, each curb roller used by the curb attachment may engage and roller along an upper wall of a curb as screeding operations are conducted on poured concrete alongside the curb.

Automatically adjustable rolling screed

Abstract: A material leveling system includes a leveling-implement assembly adapted for leveling material to a final grade level, a frame supporting the leveling-implement assembly, and an implement positioning assembly controlling the position of the leveling-implement assembly relative to the frame. The leveling-implement assembly includes an implement that contacts a construction material during the leveling process.

Built-in heating device for screed of paver

Abstract: The utility model discloses a built-in heating device for a screed of a paver, which adopts the structure that heating devices of a exhaust pipe, flame spraying nozzles, an igniter, an air-flue gas mixing box and the like are all arranged in an inner chamber of a box body of the screed; wherein the crater of each flame spraying nozzle faces the screed; the outer end of the exhaust pipe is connected with a control valve through an air delivery pipe; the control valve is connected with an air storage tank through an air delivery pipe, and is connected with a control box through a signal wire; the control box is mounted in the cab of the paver, and is connected with the igniter through a signal wire; a plurality of craters of the flame spraying nozzles are provided and face the screed; and a baffle used for controlling the reaching area of heat is arranged in front of each flame spraying nozzle. A staff in the cab can control the heating period, the procedures of ignition, flameout and the like through operation of the control box, so that the built-in heating device has the advantages of convenient and fast operation, reduced work intensity, and improved work efficiency.

Screed Machine for Preparing a Stone Base

Abstract: A screed machine is formed with a forwardly positioned screed assembly including a wedge portion and pivoted wing members. The frame is supported on two rollers spaced behind the screed assembly, which is mounted on a mast for vertical movement in conjunction with a laser receiver that provides a signal from a laser level indicating the final desired grade of the stone base. The machine can be turned at a corner by extension of a jack stand to elevate the machine for rotation about the axis defined by the centrally located jack stand so that the screed machine can be redirected into a different direction without disturbing the final grade of the stone base. The screed machine is manually moved along the stone base by an operator pulling on the handle pivotally connected to the frame. A sight line provides a monitor for the lateral orientation of the screed assembly.

Spreading machine and edge baffle of screed thereof

Abstract: The utility model discloses an edge baffle of a screed used for a spreading machine. The edge baffle comprises a movable plate (22) and a fixed plate (21) and also comprises a connecting device (24), a first adjusting arm (23) and a locating part (24), wherein the connecting device (24) is used for connecting the movable plate (22) and the fixed plate (21); the first adjusting arm (23) is pivoted with the fixed plate (21) by a first rotating shaft (233); the first adjusting arm (23) rotates around the first rotating shaft (233) to drive the connecting device (24) to move and adjust the height of the fixed plate (21) relative to the movable plate (22); and the locating part has proper accuracy and is used for fixing the relative position of the first adjusting arm (23) and the fixed plate (21). The utility model also discloses the spreading machine comprising the edge baffle of the screed. The spreading machine and the edge baffle of the screed thereof can not only have the adjustment accuracy meeting the requirement, but also have higher adjustment sensitivity.

Screed working apparatus

Abstract: A screed working apparatus comprising a frame adapted to be mounted on a vehicle, a first elongate beam being mounted on said frame to extend transverse to the normal direction of movement of the apparatus for levelling for levelling loose or plastic materials, wherein a vibration imparting device is coupled to, or mounted on, said first elongate beam to impart vibratory motion to said first elongate beam.

Hydraulic control arrangement for the screed of a road finisher

Abstract: A hydraulic control arrangement for activating a double-acting actuating cylinder, which is connected on the piston side to a road finisher and on the piston-rod side to a screed of the road finisher, is provided. The hydraulic control arrangement includes a supply connection, a tank connection and two consumer connections, in which a loading pressure or a relief pressure is applied to the piston of the actuating cylinder via the consumer connections. The loading pressure or relief pressure is controlled as a function of a defined operating state, and, in a controlling-the-screed-load operating state, the relief pressure supplied to the actuating cylinder on the piston-rod side is controlled via a proportional pressure control valve.

Shift box for screed box and bead dispenser box deployment

Abstract: A thermoplastic line striper has a shift box assembly (10) which guides the screed box (12) and bead dispenser box (14) to following positions: 1) the deployed position where the screed box (12) is down and screed gate (18) is open and the bead box dispenser wheel is engaged; 2) non-deployed and down on ground where the screed box (12) is down, the screed gate (18) is closed and the bead box (14) dispenser wheel is disengaged; and 3) non-deployed and raised off the ground where the screed box (12) is raised up, the screed gate (18) is closed and the bead box dispenser (14) wheel is disengaged. In this third position, the stick shift (20) is locked for transport mode by hooking it behind hook (22) in shift plate (24).

Paving thickness adjustor and paver with same

Abstract: The utility model discloses a paving thickness adjustor, which comprises a front big arm, a rear big arm, a screed, a big arm position adjustment mechanism and a screed position adjustment mechanism;the rear big arm is hinged with the front big arm, and a screed holder on which the screed is mounted is hinged with the rear big arm; both ends of the big arm position adjustment mechanism are respectively hinged with the front big arm and the rear big arm, and the length between both ends of the big arm position adjustment mechanism can be adjusted; both ends of the screed position adjustment mechanism are respectively hinged with the rear big arm and the screed holder, and the length between both ends of the screed position adjustment mechanism can be adjusted. Because the rear big arm andthe front big arm can rotate relatively, the height and elevation angle of the screed relative to the ground can be respectively changed by adjusting the length of the big arm position adjustment mechanism and the length of the screed position adjustment mechanism, so that the paving thickness of a paver can be conveniently adjusted, and thereby the maximum paving thickness of the paver can be increased. On the basis, the utility model also discloses a paver with the paving thickness adjustor.

Wheeled concrete screeding device

Abstract: A wheeled concrete screeding device includes a wheeled unit having wheels for movably supporting a frame portion, and a screed head supported at the frame portion and following behind the wheeled unit when the wheeled unit is moved in a screeding direction. The screed head includes a grade establishing element and a vibratable member. The grade establishing element is generally vertically adjustable responsive to a signal from a laser receiver disposed at the screed head to establish a struck-off surface of the uncured concrete at a desired grade. The vibratable member is adjustably attached at the grade establishing element and the vibratable member at least partially floats behind the grade establishing element on the struck-off surface of the uncured concrete and is at least partially supported at the struck-off surface of the uncured concrete as the wheeled unit is moved in the screeding direction.

Hydraulic control assembly for the screed of a road finisher

Abstract: The arrangement (1) has consumer connections (7, 8) for pressurizing a piston (2a) of a double-acting actuation cylinder (2) with load pressure or relief pressure. A pressure regulating valve (15) i.e. proportional valve, regulates the relief pressure, which is applied to the actuation cylinder. The load- or relief pressure is controllable based on a traveling speed of a road finisher. Hydraulic oil is pushing out from a piston side of the actuation cylinder and is supplied to a tank connection (6) through directional valves (11, 13).

Ergonomic concrete screed handles

Abstract: A paired set of handles attaching to a board forming a concrete screed to minimize the strain on a person performing concrete finishing work allows for an ergonomic application of downward force applied to the lower end of the handles and application of an upward lifting force by the shape of the grip portion at the upper end of the handles, with the shape and contour of the handles requiring less strain and strength than current screed handles.

A support member

Abstract: A support member (10) for use in placing concrete on a corrugated metal decking floor and for supporting screed rails or the like at an adjustable height to control the level and thickness of the concrete laid on the decking consists of a support plate (14), extending transversely across one of the longitudinally extending corrugations of the decking, having ends (16) shaped to engage in wedging contact with the sides of the corrugation when the support plate (14) is rotated about an axis perpendicular to the plane of the support plate (14)

Method for laying a road paving and paving screed

Abstract: The method involves automatically adjusting a stroke (H) of a condensing unit (13) in dependence of an installation parameter such as installation speed or coating thickness. Frequency (F) or angle of incidence (alpha) of a screed (3) is automatically adjusted in dependence of the installation parameter. An independent claim is also included for a screed for a road finisher.

Analysis of a Flexible Concrete Arch

Abstract: Arch bridges have been in existence for thousands of years and many of them are testament to the durability of such structures. There are approximately 70,000 masonry arches in the UK, many of them forming an important part of the UK road and rail network, equating to approximately 40% of the total used within the UK. ‘FlexiArch’ is a pre-cast concrete arch system which was developed in Queen’s University, Belfast. Individual concrete voussoirs precast to the correct taper for a given span and rise, are connected by a polymeric membrane, which allows them to form an arch when lifted. Modern durability issues of rebar corrosion are avoided as the arch system requires no internal reinforcement. This paper investigates the construction and testing of three third-scale FlexiArch models that have been built in the laboratory under a number of variables. Geotechnical tests alongside non-linear finite element analyses have also been done to determine the influence of the granular backfill. 134 ARCH’10 – 6th International Conference on Arch Bridges Figure 1: Components of FlexiArch system 2 DESIGN AND CONSTRUCTION OF THE FLEXI-ARCH SYSTEM Third-scale 5m x 2m (span x rise) arches were constructed in the laboratory. The geometry of the voussoir blocks was calculated from the overall span and circular profile of the arch. Eight moulds were then designed and made for these using ‘Lexan’ plastic, with the addition of solid tubes to create the hollowcore design (Fig.2). These tubes were removed when casting solid voussoirs in the same moulds. 23 hollowcore blocks of depth 66mm and length 333mm were used to construct each arch with a design span of 1.67m and rise of 0.67m. A third-scale concrete mix was used with a 28-day strength in excess of 30N/mm. Hooks were made using rebar and cast into 3 of the blocks for each arch made. Figure 2 : Hollowcore Voussoir Moulds (left); Voussoirs after demoulding (right) After curing, the top of the blocks were roughened with an angle grinder in order to improve the bond with the screed. The voussoir blocks were then laid on a flat construction bed, and the polymeric reinforcement was cut and bonded to the top of the blocks. ERS strain gauges were then attached to the polymeric reinforcement using an epoxy glue. The strain gauges were attached at the midspan, lifting hooks and the end voussoir blocks to enable strain measurement to be recorded at critical locations for both the construction phase and under load testing. Adhesive was then applied to the surface of the voussoirs to provide a sound bond between them and the 13mm top screed thus connecting each voussoir. The top screed caps the geotextile which connects each block together. Vibration was not possible for a screed of this depth, so the top surface was floated and after one hour crack inducers were then scored into the screed (above the edges of each block below) to ensure controlled cracking at the joints during lifting into the arch form. After the screed had cured for a minimum of seven days, the arch was lifted three times and the strain measured in the polymeric reinforcement (due to carrying the self-weight of the arch) during lifting and lowering. The maximum strain in the polymer was found to be 1200μ, well below the capacity of the material. 3 TEST SET-UP AND PROCEDURE The arch was then placed on correctly sloped anchor blocks under a hydraulic load actuator. The formwork was designed and placed with steel on one side and a strong clear ‘Lexan’ plastic on the other side so that deformation and hinge development could be observed during testing. John Bourke, SE Taylor, D Robinson, etc. 135 Deflection transducers and vibrating wire strain gauges were then installed under the arch on the intrados at the midspan, third points and near the abutments. The arch was then subjected (without backfill) to a proof load with a guideline deflection of 5mm. The arch was then backfilled with granular material in equal 100mm layers on both sides of the arch ring to avoid eccentricity and each layer was compacted using a vibrating hammer with a flat attachment. Deflections under the intrados of the arch were recorded during backfilling operations, but were found to be minimal. The complete third-scale arch bridge was then tested, with the load applied across a 150mm wide plate. In total, three arch rings were constructed and tested. Each model was built with the same span to rise but different backfill was used in test arches 2 & 3. The first arch was constructed with a 44mm diameter core in the voussoirs (as shown in Fig.3), the second was constructed with solid voussoirs, and the third arch was constructed also with hollowcore design like the first (Fig.3).

Screed die pivot removal system

Abstract: The screed box (12) rides coplanar to the road surface (14) by pivoting independently of the thermo striper machine (16). This allows the user to create more uniform lines and reduces unsightly pooling of thermoplastic caused by "rocking" of the screed box (12). A machined shaft (18) attached to the screed box (12) pivots in the pre-tensioned mounting bracket (20) on the thermo striper (16). The screed box (12) pivots axially in this mount (20) when it travels over a surface (14), which may be non-coplanar to the plane created by the three wheel points on the thermo striper (16) as shown in Figures 4 and 5. To remove the screed die (12), the pivot mount (20) is relieved of spring (24) tension by pressing down by hand or foot the handle (22) mounted to the pivot (20).

Screed device of road paving vehicle

Abstract: PROBLEM TO BE SOLVED: To surely prevent a deposit of asphalt mixture slag from intruding into a screed body from a gap between a tamper edge and the screed body. SOLUTION: This screed device 19 of a road paving vehicle includes a tamper 27 for compacting a road surface by moving the tamper edge 32 upward and downward. In the screed device 19, a mixture retention device 24, which receives and accumulates an asphalt mixture ascending through the gap between the screed body 25 and the tamper edge 32, is installed. The mixture retention device 24 is provided with a mixture retainer piece portion (vertical wall portion) 24a which is elongated in a vertical direction. When the asphalt mixture slag with a weight as heavy as/heavier than the weight exceeding an adhesive force is accumulated in the mixture retention device 24, the asphalt mixture slag falls by self-weight or is separated from the mixture retainer piece portion 24a. This disables the asphalt mixture slag from getting over the mixture retainer piece portion 24a, intruding into the screed body 25 and being accumulated therein. COPYRIGHT: (C)2010,JPO&INPIT

Mineral heat-insulation material

Abstract: The method for applying a heat insulation layer to an area is characterized in that alpha-hemihydrate or beta-gypsum or lime-alpha-hemihydrate or a mixture thereof is mixed as hydraulic binder with a pore former consisting of aluminum powder, mixed with ground limestone, and citric acid with addition of water and is cast in liquid or pasty form onto the area. The mixture has a pH of 11.8 or more. The constituents are preferably mixed on site, namely in such a consistency that the mixture is self-leveling. Placement on the laying site can e.g. be carried out by means of a floor screed pump. The material expands to the desired total thickness, yielding a homogeneous insulation layer of uniform thickness and quality and of high strength that will reach its high final strength after about 24 hours. The material can also be applied in a pasty consistency to a wall.

Method for laying pavement, screed, and road paving vehicle

Abstract: PROBLEM TO BE SOLVED: To provide a method for laying pavement of uniform thickness in the moving direction of work and performing uniform compaction in both the moving direction of work and a transverse direction, and to provide a screed and a paving vehicle. SOLUTION: A compacting unit 13, particularly a tamper 14, pre-compacts a paving material in an operation cycle with selectable stroke and selectable frequency while laying pavement selectable in pavement thickness at a selectable paving speed. At least the stroke is automatically adjusted along a characteristic curve or within a characteristic map in response to at least one paving parameter such as at least the paving speed and/or the pavement thickness. In the screed 3, the compacting unit 13 comprises an adjusting mechanism operable during the paving work for adjusting the stroke of the compacting unit 13. COPYRIGHT: (C)2011,JPO&INPIT

Quick-change heating device of multifunctional paver

Abstract: The utility model discloses a quick-change heating device of a multifunctional paver. The quick-change heating device comprises a heating pipe arranged on a screed mechanism of the paver in the length direction, and a combustor arranged opposite to a heating opening on the screed mechanism and connected on the heating pipe, wherein a plurality of support frames are arranged on the screed mechanism in the length direction, spring clips used for supporting and connecting the heating pipe are arranged on the support frames, and pipe fixed clips used for preventing the radial rotation and axial movement of the heating pipe are also arranged on part of the support frames. The utility model has the advantages of reasonable design, rapid and convenient installation and detachment as well as labor conservation, and the work efficiency is improved.

Screed and method for testing gas sealability of the screed

Abstract: PROBLEM TO BE SOLVED: To provide a screed and a method for testing gas sealability of the screed which enable economical test of gas sealability in a shorter time with a simple structure. SOLUTION: The most upstream opening and closing valve 21 and the most downstream opening and closing valves 27-30 are installed respectively at one end of the most upstream end of a gas supply pipe 16 of the screed 5 in the gas flow direction T and the other end of the most downstream end in the gas flow direction T, and pressure detecting means 31-34 for detecting gas pressure in the gas supply pipe 16 are installed between the most upstream opening and closing valve 21 opening and closing the gas supply pipe 16 and the most downstream opening and closing valves 27-30. Before starting paving work, the most upstream opening and closing valve 21 is opened to supply fuel gas from a gas cylinder 15 into the gas supply pipe 16, and when the indicated pressures of the pressure detecting means 31-34 become a predetermined pressure, the most upstream opening and closing valve 21 is closed, and the gas sealability is evaluated based on the presence of a decrease in the indicated pressures of the pressure detecting means 31-34. COPYRIGHT: (C)2010,JPO&INPIT