A method of manufacturing prestressed concrete structures
(57) Abstract:The invention relates to the construction of buildings and structures for various purposes. The goal is to simplify the work with labor savings, increased migration, rational use of material properties and reliability of operation. The method includes the erection of a large and long-span structures with the creation of the preliminary voltage working rebar in construction conditions during differentiation of the strength of concrete in manalicious layers, using the technology of preparation and curing of reinforced concrete. The magnitude of the prestress is normalized by its value with the efforts from permanent and temporary loads. 6 Il. The invention relates to the construction of buildings and structures for various purposes.There is a method of pre-stressing reinforcement for concrete used for its compression to improve crack resistance and stiffness. Thus pre-tensioned reinforcement is ignored in specially provided for in section design of channels with subsequent inject them in solution to avoid corrosion of steel (1).The disadvantages of the method: the complexity of the counter what creates real conditions for accelerated corrosion of steel and the sudden collapse of structures. In addition, the regulation of permissible operating pressure during compression of the concrete is associated with an increase of its massiveness, the consumption of materials and resources. How irrational uses of long ropes.Known external voltage rebar concrete for compression when it is located outside the cross-section, for example, blocks of the superstructure of the bridge (2).Disadvantages: lack of clutch pre-tensioned reinforcement when exposed to the temperature of heating increases operational voltage; estimated cost overruns steel is 25% required spectrasite from mechanical damage and corrosion.Known monolithic slabs, made with UN-tensioned reinforcement of low strength that allows overspending steel (3).Despite the massiveness of the beam plates and the amount of concrete they are characterized by small span (2,2 2,7 m) and the presence of edges, which complicates the device casing; an inner columns with small increments (5 to 7 m), reduces the adaptability of the production processes in operation. Usually this is a single grade of concrete and its density that the high degree of complexity leads to excessive cement.N the s for the industrial production of precast and prestressed concrete by tension reinforcement stops and subsequent cast concrete in construction conditions (4).The disadvantages of the method are the complexity and the lack of stiffness of prestressed concrete products.The aim of the invention is to simplify the work with labor savings, increased migration, the rational use of material properties and improving the reliability of operation.This goal is achieved by the fact that in the method of manufacturing prestressed reinforced concrete structures for industrial production of precast and prestressed concrete by tension reinforcement stops and subsequent cast concrete in construction conditions, the cable pull on the armature clamped in parts of a building or structure stops, with the permanent fixing of the second end of the slot wedge pads, connected by buckles of pieces, high-strength wire with non-stressed steel meshes and by clamps to the edges of the ridges through the strip with a suspended formwork and monolithic concreting produced in two stages, at the first stage produces a concrete with an initial controlled elongation of the cable fittings when the tension corresponding to the voltage it 0,35 Rsnand n the corresponding resistance of the cable fittings stretch.In Fig. 1 shows a plan of the manufactured structure with the location of the hydraulic cylinder; Fig. 2 section a-a in Fig. 1; Fig. 3 cross-section B-B in Fig. 1; Fig. 4 the node In Fig. 2; Fig. 5, the node G in Fig. 2; Fig. 6 schematic efforts in the ropes at their constant tension on the lugs, and emerging from the load.The proposed method for the manufacture of pre-stressed concrete structures includes:
the device stops 1, permanently sealed in the cell or part of a building or structure;
the fixing of the pad 1 distribution of beams 2, combined with the anchor pads 3 with conical sockets hollow locking wedges 4;
coaxial installation of the hydraulic cylinder 5 together with protonirovannoi pumping station with its temporary attachment to the beam 2;
project anchoring one end of the rope 6 in block 3 with the wedge 4;
institution other end of the rope 6 in the nest pads 3;
threading wedge 4 through the end of the rope 6 with a temporary fixation of the latter in clamping hydraulic cylinder 5.creating pressure in hydroxamate Jack 5, synchronous with increasing force and prestress in the rope 6 with the control of elongation based on the chart tensile steel
(l=k; l l)
stop with the calculated lightweight concrete step bars-jumper 7 on the ropes 6;
the rollers on the bars-jumper 7 on the schematic diagrams of bending moment from a uniformly distributed load of welded rolled grids 8 with fastening pins 9 pieces of high-strength wire;
installation with the calculated step bars-jumper 7 inverted shackles of round steel with threads 10 for fixing shuttering boards 11 with square concrete pads 12 and clamping strips 13;
styling, shaping and hardening of the lower layer of lightweight concrete 14 (D 1500 B30) for monolithic guaranteed grip products 5, 7, 8 with the layer height h1;
styling, shaping and curing of the top layer non-autoclaved aerated pneumobilia 15 (D; 5) the height of the layer h2to improve the resistance of the local punching shear thin-walled concrete 14 and, for example, to ensure the acoustic ceilings or insulation coatings.The application of the method is reliable, ensuring operation prestressed solid products in the design service life of reinforced concrete made from parts 1, 2, 3, 4, 6, 7, 8, 9, 10, 14, 15. The appropriate safeguards contributes to testing the application of V-clamps in their original manufacturing techniques pravlenie forces of elasticity in prestressed beams with cable fittings) confirmed experimentally. So, after their discharge, despite the significance of cracks from the load close to Deplete, there was a tendency to reduce deflections, and with the increased eccentric compression full exception with the regeneration of bending. At constant prenebrezhenii americanna ropes, i.e. in the absence of the process of creep of concrete poured, the deflections will be significantly reduced. Conversely, the degree of the rational properties of high-strength reinforcing ropes in connection with the loss of their pre-stress due to creep of concrete will increase. Moreover, due to the algebraic summation of the initial tension of the ropes with secondary, caused by efforts from transverse loading monolithic structures remains stable generated prestress ropes within their deformation together with the clutch factor. Implemented and the ability to control the differentiation of the interaction of prestress (PspNpanelwith efforts from the constant (Npost) and temporal (NBP) load the converted and refined inequalities
Npost< NBP< PspNpanel0,35 RsnAsn; (1)
(Nfull+ Psp) 0,70 RsnAsnThe + NBP(3)
The choice of the strength of the layers of concrete (In) together with the thickness (h1and h2optimizes the amount of effort from constant load (1) and (2) rational consumption cable fittings with the appropriate technological tools.The method provides increased spans of solid floor slabs several times while conserving materials and resources by eliminating additional reinforcement and increasing the size of the concrete cross-sections, due to the need of perception of effort arising from the removal from the pallet, transportation and installation of precast prestressed structures inherent in the technology adopted by the prototype. Reduced complexity due to the simplification of reinforcement for the use of high-strength ropes, having increased its original length in the composition, for example, ceilings, deprived of external edges, requiring complexity of reinforcement and shuttering works. A METHOD of MANUFACTURING prestressed reinforced CONCRETE STRUCTURES for industrial production of precast and prestressed concrete by tension reinforcement stops and subsequent cast concrete in construction conditions, characterized in that the receiving of the second end of the slot wedge pads, connect by means of clips made of pieces of high-strength wire with non-stressed steel meshes and by clamps to the edges of intersections through the strip with a suspended formwork and monolithic concreting produced in two stages, the first stage produces a concrete with an initial controlled elongation of the cable fittings when the tension corresponding to the voltage it 0,35 Rsnand in the second stage, the total voltage in the armature with regard to efforts from the load is 0.7 Rsnwhere Rsnregulatory resistance of the cable reinforcement tensile strength.
FIELD: apparatuses for fastening reinforcing parts, for example mutually crossed reinforcing rods.
SUBSTANCE: drum around which wire for fastening reinforcing rods is wound is mounted in shaft arranged in housing. Annular recess is formed along edge of opening of housing. Diameter of said recess exceeds that of lower part of housing. At side of opening of housing drum has flange arranged in said annular recess. On inner peripheral surface of opening of drum boss there is dent for preventing drum separation from its mounting shaft. On outer edge surface of shaft there is mounting recess for engaging dent.
EFFECT: improved design preventing wire penetration into gap between housing and drum, enhanced operational reliability of drum and machine for binding reinforcing rods.
4 cl, 27 dwg
FIELD: preparing, conveying, or working-up building materials or building elements in situ, mounting and prestressing of reinforcing inserts.
SUBSTANCE: reinforcing bar binder feeds wire while rotating a wire reel installed in chamber and binds reinforcing bars. The chamber comprises the first detecting means to detect wire reel rotation and the second detecting means to detect number of second wire reel parts to be detected during reel rotation by the first detecting means. Binder body is provided with control means to control the amount of fed wire or wire torque depending on the number of second parts detected by the second detecting means.
EFFECT: increased structural simplicity and provision of automatic regulation of fed wire amount and torque thereof.
12 cl, 19 dwg
FIELD: equipment designed for fastening reinforcement by means of wire, for example for fastening mutually crossing reinforcing rods, possibly in building.
SUBSTANCE: machine includes housing; rotating drum carrying wire for fastening reinforcing rods; unit for controlling drum rotation; one or more detected objects. Detected object may be placed on lateral surface of drum. At controlling rotation of drum, said object is detected through opening of lid providing light reflection from light irradiator. Light reflected from detected object and light reflected from lid is received for determining difference between their intensity values.
EFFECT: enhanced operational reliability of machine, elimination of errors at monitoring wire consumption.
12 cl, 40 dwg
SUBSTANCE: armature guy is carried out at first in angular cells on construction contour, then in central cell, after in cells adjoining to central cell on all central axis across construction, then on cells of layer adjoining to central layer of cells in direction to external contour and at the end cells located on construction perimeter. In angular cells an armature guy is made in spans between a corner pillar and the first from it in two axes on construction location. In cells adjoining to central cell, on all central axis a guy is made on longitudinal spans on construction location, on cells of a layer adjoining to central layer of cells, guy is made in two mutually perpendicular spans, beginning from central axes concerning central cell, thus guy on different parts is carried out by different devices.
EFFECT: increase of load-carrying capacity of construction floorings and reliability of devices for armature guy.
7 cl, 8 dwg, 1 ex
SUBSTANCE: invention is attributed to construction engineering and can be used for binding of reinforcement cages of concrete products. Reinforcement hook contains shaft on one end of which handle is installed which can be rotated, and the second end of the shaft is tapered and bended as hook. Lever is hinged on the handle. The lever is capable to change position relative to handle. Two more levers are installed on shaft of reinforcement hook which levers can travel along hook and relative to each other and they are interconnected by elastic element. As a result due to simple fastening elements using, binding with wire pieces without loop is provided and production is cheapened.
EFFECT: cheapening of construction.
FIELD: construction industry.
SUBSTANCE: mechanism is intended for attaching extended elements to each other, and especially such elements as reinforced bars and electric cables by means of at least one wire. Mechanism consists of two jaws (6, 7) moved down on the elements to be connected (8). There are provisions made for means (20) of supplying wire (12) along guide surface (10) of the first jaw (6) to guide surface of (11) the second jaw (7), thus forming a wire loop which envelopes the above elements on three sides, and in this case ends of this loop can be twisted on the fourth side of elements (8). Twisting means consist of device (14) rotating relative to jaws (6, 7) and guiding the wire (12) at its supply to jaw and removal from jaw.
EFFECT: providing possibility of wire straightening with overcoming the resistance by the value required for twisting the wire loop ends.
25 cl,13 dwg
FIELD: engines and pumps.
SUBSTANCE: reinforcing bar wire-tying machine incorporates wire drum with data detection and wire identification device designed to detect and identify wire on the drum flange side surface and allows wire twist force or feed amount control proceeding from the wire identification data detected in starting wire-tying with the help of the rotation detection lever. The drum comprises cylindrical bush with a pair of flanges on its sides and has an extending section on the outer side surface with a reflecting symbol on the bush outer side surface. The type of wire coiled around the said drum is determined from the number of disclosed reflecting symbols when the detection signal is input from the aforesaid lever. The wire data is detected at the drum high-rotation wire-tying speed, not in coiling the wire on the drum.
EFFECT: reliable wire-type data detection.
21 cl, 9 dwg
SUBSTANCE: method includes use of a piece of the wire as fastening element which part is bent with formation of the lug for grasp with reinforcement cage, fastening element supply under flooring of reinforcing bars, lug grasp with reinforcement cage, throwing of fastening element through it from condition of an arrangement of flooring of reinforcing bars in wire loop and a tightening of a loop several turns of the reinforcement cage at deduction of a tail of the fastening element. For this purpose use the manual delivery unit; the container with a holder for placing of the fastening elements is established in its case, submitting gear and a clip. The manual delivery unit is brought to flooring of reinforcing bars, the fastening element is taken from the container, and the fastening element supply under flooring of reinforcing bars is carried out by its telescopings by means of the delivery unit. Holding of a tail of the fastening element at tightening of a loop by turns of the reinforcement cage is performed by means of a clip of the mentioned device which sizes allow to carry out joining in close places.
EFFECT: labour productivity increases.
FIELD: construction industry.
SUBSTANCE: reinforcing bars of reinforced concrete structures are set into place and attached manually with a reinforcing hook using fasteners. A piece of wire is used as fastener, and some part thereof is bent into halves so that a closed or open loop with a tail piece can be formed of one or two wire strands. Reinforcing hook is equipped with a lock that allows maintaining the fastener's tail piece.
EFFECT: invention allows improving labour capacity when attaching bars by means of reinforcing hook.
FIELD: mechanical engineering.
SUBSTANCE: invention refers to mechanical engineering and can be used in machine for reinforcement material binding with wire. The reel is fitted with reel rotation control sensor. The reel has two flanges, inner cylinder area where reel mounting shaft is inserted, and outer cylinder area around which wire is spooled. Between inner and outer cylinder area there are multiple objects with quantitatively differing physical characteristics which objects are detected by reel rotation control sensor.
EFFECT: reliable wire consumption detection is provided.
4 cl, 40 dwg