Concrete support structure and construction method based on beam haunching and slow-bonding prestressing

Abstract

The application discloses a concrete support structure based on beam haunching and slow-bonding prestress and a construction method, and the support structure comprises a tensioning end side mold, a fixed end side mold and an intermediate side mold used for manufacturing a prestressed beam, a haunching side mold used for adding a haunch to the end of the prestressed beam, a haunching beam haunching place side mold fixing mechanism used for fixing the haunching side mold, a tensioning end prestressed tendon installation assembly arranged on the tensioning end side mold, a fixed end prestressed tendon installation assembly arranged on the fixed end side mold and prestressed tendons; the haunching beam haunching place side mold fixing mechanism comprises a haunching beam self-adapting U-shaped fixing clamp and a plurality of haunching beam haunching length adjusting units arranged in parallel and at intervals from top to bottom between adjacent two haunching beam self-adapting U-shaped fixing clamps; the haunching beam haunching length adjusting units are adjusted to adapt to haunching side molds with different lengths, the haunching of the prestressed beam is realized, and then an operable space is provided for the tensioning end when the slow-bonding prestressed tendons are tensioned.

Description

TECHNICAL FIELD

[0001] The present application belongs to the technical field of building construction, and more particularly relates to a concrete support structure based on beam haunching and slow-bonded prestress and a construction method. BACKGROUND

[0002] The pre-tensioning method and the post-tensioning method are two main construction methods of prestressed concrete structures, and the shortcomings of the pre-tensioning method mainly include: 1. A special tensioning pedestal and a larger tensioning space are needed, which increases the construction cost and limits its application in some projects. 2. The problems of the fixed and anti-loose of the prestressed steel bars need to be properly solved to ensure the stability of the prestress. 3. The pre-tensioning method is generally only suitable for short precast components, and the construction difficulty will increase for large components or curvedly arranged prestressed steel bars; the shortcomings of the post-tensioning method mainly include 1. The bonding force between the prestressed steel bars and the concrete is poor, which may cause uneven distribution of the prestress and affect the stress performance of the structure.

[0003] The slow-bonded prestress technology is a new type of prestress technology developed in recent years, and is the third prestress system after the unbonded and bonded prestress. The slow-bonded prestress is similar to the unbonded prestress, and compared with the bonded prestress, it does not need to pass through a corrugated pipe and does not need to be grouted, which reduces two complex processes and reduces the influence of on-site manual operation, and the construction quality is easy to be guaranteed. However, the following problems will be encountered in the construction process of the slow-bonded prestressed steel bar: 1. The operable space of the tensioning end is narrow and difficult to operate when the slow-bonded prestressed steel bar is tensioned; specifically, when a section of beam collinear with the beam end is connected to the beam end by using the traditional tensioning method, the tensioning can only be performed on the side surface of the beam end, not only the space is narrow, but also the stress of the prestressed steel bar is affected, and the overall quality cannot be guaranteed; 2. Since the side surface of the haunched beam is an inclined surface, the side mold cannot bear the normal pressure, which leads to the problem that the whole length of the tensioning screw cannot be used for the tie, and the traditional method is to weld the screw on the main beam steel bar, and there is no mature treatment method. SUMMARY

[0004] In view of the above defects or improvement needs of the prior art, the present application provides a concrete support structure based on beam haunching and slow-bonded prestress and a construction method, which solves the problem of narrow and difficult-to-operate space of the tensioning end when the slow-bonded prestressed steel bar is tensioned by adding a haunch to the side of the prestressed beam end; the problem that the whole length of the tensioning screw cannot be used for the tie due to the fact that the side mold cannot bear the normal pressure because the side surface of the haunched beam is an inclined surface is solved by using the side mold fixing mechanism at the haunch of the haunched beam to fix the side mold; the adjustable function of the side mold fixing device at the haunch of the haunched beam is used to fix the side mold of the haunched beam with different length, height and width; the present application does not need to open a screw hole in the middle of the side mold of the haunched beam and does not need to be welded, which saves time and effort and reduces cost and increases efficiency; and the problems occurring in the tensioning process of the prestressed steel bar of the prestressed beam can be effectively solved.

[0005] To achieve the above object, one aspect of the present application provides a concrete support structure based on beam haunching and slow-bonded prestress, comprising a tensioning end side mold, a fixed end side mold, an intermediate side mold for making a prestressed beam, a haunching side mold for haunching the end of the prestressed beam, a haunching beam haunching place side mold fixing mechanism for fixing the haunching side mold, a tensioning end prestressed tendon installation assembly provided on the tensioning end side mold and a fixed end prestressed tendon installation assembly provided on the fixed end side mold, and a prestressed tendon provided between the tensioning end prestressed tendon installation assembly and the fixed end prestressed tendon installation assembly; wherein,

[0006] The intermediate side mold is provided between the tensioning end side mold and the fixed end side mold; the haunching beam haunching place side mold fixing mechanism comprises a haunching beam self-adaptive U-shaped fixing clamp provided at the haunching end of the tensioning end side mold, the fixed end side mold and the intermediate side mold respectively, and a plurality of haunching beam haunching length adjusting units provided in parallel and at intervals from top to bottom between adjacent two haunching beam self-adaptive U-shaped fixing clamps; the haunching beam self-adaptive U-shaped fixing clamp is adjusted to adapt to prestressed beams of different widths and heights; the haunching side mold is provided between the tensioning end side mold and the intermediate side mold, and between the intermediate side mold and the fixed end side mold respectively; the haunching beam haunching length adjusting unit is adjusted to adapt to haunching side molds of different lengths, so as to realize haunching of the prestressed beam; and the prestressed beam is haunched at the end to provide an operable space for tensioning of the slow-bonded prestressed tendon.

[0007] Further, the tensioning end prestressed tendon installation assembly comprises a clamping anchor provided on the side of the tensioning end side mold, a first pressure receiving plate, and a first spiral tendon;

[0008] The centers of the clamping anchor and the first pressure receiving plate are collinear;

[0009] The clamping anchor is provided on the side of the second side plate close to the first side plate;

[0010] The first pressure receiving plate is provided on the side of the clamping anchor away from the second side plate;

[0011] The first spiral tendon is provided on the side of the first pressure receiving plate away from the clamping anchor;

[0012] The tensioning end of the prestressed tendon sequentially passes through the first spiral tendon, the first pressure receiving plate, the clamping anchor and the second side plate and extends to the other side of the second side plate;

[0013] The fixed end of the prestressed tendon is fixed by the fixed end prestressed tendon installation assembly and the fixed end side mold.

[0014] Further, the fixed end prestressed tendon installation assembly comprises a second pressure bearing plate arranged on the fixed end side mold near one side of the intermediate side mold, a second spiral tendon, and an extrusion anchor arranged on the fixed end side mold away from one side of the intermediate side mold.

[0015] The center of the second pressure bearing plate and the extrusion anchor are collinear, and are arranged on both sides of the formwork of the fixed end side mold;

[0016] The second spiral tendon is arranged on the side of the second pressure bearing plate away from the extrusion anchor;

[0017] The fixed end of the prestressed tendon passes through the second spiral tendon, the second pressure bearing plate, the formwork of the fixed end side mold, and the extrusion anchor in sequence.

[0018] Further, the prestressed tendon comprises a steel strand, a slow-bonding adhesive coated on the steel strand, and an outer sheath PE arranged outside the slow-bonding adhesive.

[0019] The surface of the outer sheath PE is provided with uneven indentations.

[0020] Further, the haunched beam self-adaptive U-shaped fixing clamp is provided with a tension screw and a U-shaped clamp lug; the U-shaped clamp lugs are evenly spaced on the side of the prestressed beam height adjusting unit.

[0021] Further, the haunched beam self-adaptive U-shaped fixing clamp comprises a prestressed beam width adjusting unit and a prestressed beam height adjusting unit arranged vertically at both ends of the prestressed beam width adjusting unit.

[0022] The prestressed beam width adjusting unit comprises a first large end and a first small end arranged movably and in plug-in connection.

[0023] The prestressed beam height adjusting unit comprises a second large end and a second small end arranged movably and in plug-in connection from top to bottom.

[0024] Adjusting grooves passing through from top to bottom are arranged on the second large end and the second small end on both sides; the lengths and positions of the adjusting grooves on both sides correspond.

[0025] The plug-in depth of the first large end and the first small end is adjusted to adapt to prestressed beams of different widths; the plug-in depth of the second large end and the second small end is adjusted synchronously to adapt to prestressed beams of different heights.

[0026] The two ends of the tension screw pass through the adjusting grooves on both sides respectively, and the two prestressed beam height adjusting units are fixed by lock nuts.

[0027] Further, the haunch beam haunch length adjusting unit comprises a plurality of groups of movable plug-in square tube large end and square tube small end; the square tube lug is arranged on the end of the square tube large end and the square tube small end away from each other;

[0028] The square tube lug is matched with the number and position of the U-shaped lug; the square tube lug at the two ends of the haunch beam haunch length adjusting unit is fixed with the U-shaped lug at the corresponding position through the bolt, so that the fixing of the haunch beam haunch length adjusting unit on the side of the haunch side mold is realized; the plug-in depth of the square tube large end and the square tube small end is adjusted to adapt to the haunch side mold and the haunch beam of different sizes.

[0029] The second aspect of the application provides a construction method of the beam haunch based on the slow-bonding prestressed concrete, which is realized by applying the beam haunch and the slow-bonding prestressed concrete support structure, and comprises the following steps:

[0030] S1: according to the design requirements, installing the tension end side mold, the fixed end side mold and the intermediate side mold in the construction area; installing the haunch side mold at the haunch part between the tension end side mold, the intermediate side mold and the fixed end side mold, and ensuring that the haunch end of each side mold is closely fitted;

[0031] S2: installing the haunch beam haunch side mold fixing mechanism on the side of the haunch side mold;

[0032] S3: installing the tension end prestressed tendon installation assembly on the tension end side mold, and installing the fixed end prestressed tendon installation assembly on the fixed end side mold; fixing the two ends of the prestressed tendon with the tension end prestressed tendon installation assembly and the fixed end prestressed tendon installation assembly respectively;

[0033] S4: arranging the fixed support on the prestressed tendon at intervals, and positioning the prestressed tendon in a curve;

[0034] S5: pouring the concrete, and after the concrete reaches 85% of the design strength, removing the beam side mold, and performing the prestressed tendon tensioning and anchoring;

[0035] S6: after the prestressed tendon tensioning and anchoring are completed, cutting the exposed excess prestressed tendon; cleaning the tension end and the surrounding thereof, plugging the tension end with the same mark micro-expansion fine stone concrete, and vibrating and compacting, so that the production of the beam haunch based on the slow-bonding prestressed concrete structure is completed.

[0036] Further, the step S2 of installing the haunch beam haunch side mold fixing mechanism on the side of the haunch side mold comprises:

[0037] S21: according to the width and height of the prestressed beam, installing the haunch beam self-adapting U-shaped fixing clamp at the haunch end of the tension end side mold, the intermediate side mold and the fixed end side mold respectively;

[0038] S22: According to the length of the haunch side mold, a haunch beam haunch length adjusting unit is respectively installed between two adjacent adaptive U-shaped fixing clamps of the haunch beam, so as to effectively fix the haunch side mold and ensure that the haunch side mold is stable and will not be displaced during concrete pouring.

[0039] Further, the step S3 of installing the tensioning end prestressed tendon installation assembly on the tensioning end side mold comprises:

[0040] A clamping piece anchor is installed on the second side plate of the tensioning end side mold, close to the side where the first side plate is located, so as to ensure that the position is accurate and aligned with the tensioning direction of the prestressed tendon;

[0041] A first pressure plate is installed on the side of the clamping piece anchor close to the intermediate side mold;

[0042] A first spiral tendon is installed on the side of the first pressure plate close to the intermediate side mold;

[0043] The step S3 of installing the fixed end prestressed tendon installation assembly on the fixed end side mold comprises:

[0044] A second pressure plate is installed on the fixed end side mold close to the intermediate side mold, and an extrusion anchor is installed away from the intermediate side mold, so as to ensure that the center lines thereof are collinear and aligned;

[0045] A second spiral tendon is installed on the side of the second pressure plate away from the extrusion anchor;

[0046] The step S3 of fixing the two ends of the prestressed tendon to the tensioning end prestressed tendon installation assembly and the fixed end prestressed tendon installation assembly comprises:

[0047] The tensioning end of the prestressed tendon is passed through the first spiral tendon, the first pressure plate and the clamping piece anchor, so as to ensure that the tensioning end of the prestressed tendon is fixed in the clamping piece anchor;

[0048] The fixed end of the prestressed tendon is passed through the second spiral tendon and the second pressure plate, and then fixed in the extrusion anchor.

[0049] Overall, compared with the prior art, the above technical solutions conceived by the present application can achieve the following beneficial effects:

[0050] The application discloses a concrete support structure based on beam haunching and slow-bonded prestress and a construction method thereof. BRIEF DESCRIPTION OF DRAWINGS

[0051] Figure 1 It is a whole arrangement state schematic diagram of the concrete support structure based on beam haunching and slow-bonded prestress of the application;

[0052] Figure 2 It is a local arrangement structure schematic diagram of the concrete support structure based on beam haunching and slow-bonded prestress of the application;

[0053] Figure 3 It is a structure schematic diagram of the tension end prestress tendon installation assembly of the concrete support structure based on beam haunching and slow-bonded prestress of the application;

[0054] Figure 4 It is a structure schematic diagram of the fixed end prestress tendon installation assembly of the concrete support structure based on beam haunching and slow-bonded prestress of the application;

[0055] Figure 5 It is a structure schematic diagram of the beam haunching self-adaptive U-shaped fixing clamp of the concrete support structure based on beam haunching and slow-bonded prestress of the application;

[0056] Figure 6 It is a local enlarged schematic diagram of the beam haunching length adjusting unit of the concrete support structure based on beam haunching and slow-bonded prestress of the application;

[0057] Figure 7 It is a local enlarged schematic diagram of the concrete support structure based on beam haunching and slow-bonded prestress of the application; Figure 1

[0058] Figure 8 It is a flow schematic diagram of the concrete construction method based on beam haunching and slow-bonded prestress of the application.

[0059] ​In all the drawings, the same reference signs represent the same technical features, specifically: 1-tensioning end side mold, 11-first side plate, 12-second side plate, 2-intermediate side mold, 21-third side plate, 22-fourth side plate, 3-haunched beam haunching side mold fixing mechanism, 31-haunched beam self-adapting U-shaped fixing clamp, 311-first large head end, 312-first small head end, 313-second large head end, 314-second small head end, 315-adjusting groove, 316-locking nut, 301-pulling screw, 302-U-shaped clamp lug, 32-haunched beam haunching length adjusting unit, 321-square tube large head end, 322-square tube small head end, 323-square tube lug, 324-latch, 4-haunched side mold, 5-tensioning end prestressed tendon installation assembly, 51-clip anchor, 52-first pressure bearing plate, 53-first spiral tendon, 6-fixed end prestressed tendon installation assembly, 61-second pressure bearing plate, 62-second spiral tendon, 63-extrusion anchor, 7-fixed end side mold, 8-prestressed tendon, 9-haunched beam, 10-prestressed tendon construction operation position. DETAILED DESCRIPTION

[0060] In order to make the objectives, technical solutions and advantages of the present application clearer, the present application will be further described in detail below with reference to the drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and should not be used to limit the present application. In addition, the technical features involved in the various embodiments of the present application described below can be combined with each other as long as they do not conflict with each other.

[0061] As Figures 1-7As shown, one aspect of the present application provides a beam haunch based slow bond prestressed concrete structure, comprising a tension end side mold 1, a fixed end side mold 7, an intermediate side mold 2 for making a prestressed beam, a haunch side mold 4 for adding a haunch at the end of the prestressed beam, a haunch beam haunch side mold fixing mechanism 3 for fixing the haunch side mold 4, a tension end prestressed tendon installation assembly 5 provided on the tension end side mold 1 and a fixed end prestressed tendon installation assembly 6 provided on the fixed end side mold 7; wherein the intermediate side mold 2 is provided between the tension end side mold 1 and the fixed end side mold 7; the haunch beam haunch side mold fixing mechanism 3 comprises a haunch beam self-adaptive U-shaped fixing clamp 31 provided at the haunch end of the tension end side mold 1, the fixed end side mold 7 and the intermediate side mold 2 respectively, and a plurality of haunch beam haunch length adjusting units 32 provided in parallel and spaced apart from top to bottom between adjacent two haunch beam self-adaptive U-shaped fixing clamps 31; the haunch beam self-adaptive U-shaped fixing clamp 31 is adjusted to adapt to prestressed beams of different widths and heights; the haunch side mold 4 is provided between the tension end side mold 1 and the intermediate side mold 2, and between the intermediate side mold 2 and the fixed end side mold 7; the tension end side mold 1 and the intermediate side mold 2 are fixed as a whole by the haunch beam haunch side mold fixing mechanism 3 and the haunch side mold 4 on the tension side; the fixed end side mold 7 and the intermediate side mold 2 are fixed as a whole by the haunch beam haunch side mold fixing mechanism 3 and the haunch side mold 4 on the fixed side; the haunch beam haunch length adjusting unit 32 is adjusted to adapt to the haunch side mold 4 of different lengths, thereby realizing the haunch of the prestressed beam; the haunch at the end of the prestressed beam provides an operable space for the tension end when the slow bond prestressed tendon is tensioned; the present application solves the problem of narrow operable space at the tension end when the slow bond prestressed tendon is tensioned by adding a haunch at the end of the prestressed beam; the problem of not being able to use a whole length of tensioning screw to tie due to the fact that the side of the haunch beam is an inclined surface and the side mold cannot withstand normal pressure is solved by fixing the haunch side mold 4 by the haunch beam haunch side mold fixing mechanism 3; the fixing of the haunch side mold 4 of different lengths, heights and widths is realized by the adjustable function of the haunch beam haunch side mold fixing device.

[0062] Further, as Figures 1-7As shown in the figure, the tension end prestressed tendon installation assembly 5 includes a clamping anchor 51, a first pressure plate 52, a first spiral tendon 53, and a prestressed tendon 8 arranged on the side of the tension end side mold 1; the centers of the clamping anchor 51 and the first pressure plate 52 are collinear; the clamping anchor 51 is arranged on the side of the second side plate 12 close to the first side plate 11; the first pressure plate 52 is arranged on the side of the clamping anchor 51 away from the second side plate 12; the first spiral tendon 53 is arranged on the side of the first pressure plate 52 away from the clamping anchor 51; the tension end of the prestressed tendon 8 sequentially passes through the first spiral tendon 53, the first pressure plate 52, the clamping anchor 51, and the second side plate 12 and extends to the other side of the second side plate 12; the fixed end of the prestressed tendon 8 is fixed with the fixed end side mold 7 through the fixed end prestressed tendon installation assembly 6.

[0063] Further, as shown in the figure, Figures 1-7 The fixed end prestressed tendon installation assembly 6 includes a second pressure plate 61 arranged on the fixed end side mold 7 close to one side of the intermediate side mold 2, a second spiral tendon 62 arranged on the fixed end side mold 7 away from one side of the intermediate side mold 2, and an extrusion anchor 63; the centers of the second pressure plate 61 and the extrusion anchor 63 are collinear and oppositely arranged on both sides of the mold plate of the fixed end side mold 7; the second spiral tendon 62 is arranged on the side of the second pressure plate 61 away from the extrusion anchor 63; and the fixed end of the prestressed tendon 8 is fixed with the centers of the extrusion anchor 63 and the mold plate of the fixed end side mold 7 sequentially passing through the second spiral tendon 62 and the second pressure plate 61.

[0064] Further, in the embodiment of the present application, the prestressed tendon 8 includes a steel strand, a slow-bonding adhesive coated on the steel strand, and an outer sheath PE arranged outside the slow-bonding adhesive; the surface of the outer sheath PE is provided with uneven indentations; the rib height of the indentations is not less than 2 mm, and the slow-bonding adhesive is filled in the ribs; when the beam end of the haunch is connected with a section of the beam collinear with the beam end of the haunch during tensioning of the slow-bonding prestressed tendon, the beam end of the haunch can only be tensioned, the operation space of the tensioning end is narrow and difficult to operate, and the two ends of the beam are provided with haunches, so that the prestressed tendon passes through the haunching position, which is convenient for construction.

[0065] Further, as shown in the figure, Figures 1-7 The structure of the tension end side mold 1 and the fixed end side mold 7 is the same; the tension end side mold 1 includes first and second side plates 11 and 12 arranged in parallel and at intervals; the intermediate side mold 2 includes third and fourth side plates 21 and 22 arranged in parallel and at intervals; the haunch side mold 4 is arranged between the first side plate 11 and the third side plate 21; different self-adaptive U-shaped fixed clamps 31 fix the first and second side plates 11 and 12 as a whole and fix the third and fourth side plates 21 and 22 as a whole.

[0066] Further, as shown in the figure, Figures 1-7As shown, the haunched beam adaptive U-shaped fixed clamp 31 is provided with a pair of pull rods 301 and U-shaped clamp lugs 302; the haunched beam adaptive U-shaped fixed clamp 31 comprises a prestressed beam width adjusting unit and a prestressed beam height adjusting unit vertically arranged at both ends of the prestressed beam width adjusting unit; the prestressed beam width adjusting unit comprises a first large end 311 and a first small end 312 movably inserted; the prestressed beam height adjusting unit comprises a second large end 313 and a second small end 314 movably inserted from top to bottom; the second large end 313 and the second small end 314 on both sides are provided with an adjusting groove 315 passing through up and down; the lengths and positions of the adjusting grooves 315 on both sides correspond; after the length of the prestressed beam width adjusting unit is adjusted to be appropriate, the two ends of the pair of pull rods 301 are respectively inserted through the adjusting grooves 315 on both sides, and the two prestressed beam height adjusting units are fixed by a locking nut 316; the number of the pair of pull rods 301 is determined according to actual needs; the insertion depth of the first large end 311 and the first small end 312 is adjusted to adapt to the production of prestressed beams of different widths; the insertion depth of the second large end 313 and the second small end 314 is adjusted synchronously to adapt to the production of prestressed beams of different heights.

[0067] Further, as shown in Figures 1-7 The U-shaped clamp lugs 302 are uniformly and evenly arranged on the side of the prestressed beam height adjusting unit; the haunched beam haunch length adjusting unit 32 comprises a plurality of groups of square tube large ends 321 and square tube small ends 322 movably inserted; the square tube large ends 321 and the square tube small ends 322 are respectively provided with square tube lugs 323 away from each other; the number and position of the square tube lugs 323 and the U-shaped clamp lugs 302 are matched; the square tube lugs 323 at both ends of the haunched beam haunch length adjusting unit 32 are fixed with the U-shaped clamp lugs 302 at the corresponding positions by means of a bolt 324, so as to fix the haunched beam haunch length adjusting unit 32 on the side of the haunch side mold 4; the insertion depth of the square tube large end 321 and the square tube small end 322 is adjusted to adapt to the haunch side mold 4 and the haunched beam 9 of different sizes.

[0068] The first big end 311 of the haunch beam self-adapting U-shaped fixing clamp 31 is sleeved on the first small end 312, which is applicable to prestressed beams with different widths; the second big end 313 of the two haunch beam self-adapting U-shaped fixing clamps 31 is sleeved on the second small end 314, which is applicable to prestressed beams with different heights by clamping the haunch beam haunch end head side mold of the tension end side mold 1 and the middle side mold 2 and adjusting the insertion depth between them; the opposite pulling screw 301 is threaded on the two side adjusting grooves 315 and is tightened with the locking nut 316; the square tube big end 321 is sleeved on the square tube small end 322, and the insertion depth between them is adjusted to adapt to different haunch beam haunch lengths; the U-shaped clamp lug 33 at the two ends of the haunch beam self-adapting U-shaped fixing clamp 31 is connected with the square tube lug 323, the bolt 324 is inserted, and the fixing effect of the haunch beam haunch side mold 4 is realized.

[0069] As Figure 8 shown, the second aspect of the present application provides a construction method of a concrete support structure based on beam haunching and slow-bonded prestress, which is realized by using the concrete support structure based on beam haunching and slow-bonded prestress, and comprises the following steps:

[0070] S1: according to the design requirements, installing the tension end side mold 1, the fixed end side mold 7 and the middle side mold 2 in the construction area; installing the haunch beam haunch side mold 4 at the haunch part between the tension end side mold 1, the middle side mold 2 and the fixed end side mold 7, and ensuring that the haunch beam haunch side mold 4 is closely attached to the haunch end of the tension end side mold 1, the fixed end side mold 7 or the middle side mold 2 to form the shape of the haunch part;

[0071] S2: installing the haunch beam haunch side mold fixing mechanism 3 on the side of the haunch beam haunch side mold 4;

[0072] S3: installing the tension end prestressed tendon installation assembly 5 on the tension end side mold 1 and the fixed end prestressed tendon installation assembly 6 on the fixed end side mold 7, and fixing the two ends of the prestressed tendon 8 to the tension end prestressed tendon installation assembly 5 and the fixed end prestressed tendon installation assembly 6 respectively;

[0073] S4: setting the fixed support on the prestressed tendon 8 at intervals to position the prestressed tendon 8 in a curve;

[0074] S5: pouring concrete, and after the concrete reaches 85% of the design strength, removing the beam side mold and performing prestressed tendon tensioning and anchoring at the corresponding prestressed tendon construction operation site 10;

[0075] S6: after the prestressed tendon tensioning and anchoring are completed, cutting the exposed excess prestressed tendon; cleaning the tension end and the surrounding area, plugging the tension end with the same number of micro-expansion fine aggregate concrete and vibrating and compacting it, and completing the production of the slow-bonded prestressed concrete structure based on beam haunching.

[0076] Further, the step S2 of installing the side form 4 of the haunch beam at the side of the haunch of the side form 3 of the haunch beam includes:

[0077] S21: installing the self-adaptive U-shaped fixing clamp 31 of the haunch beam at the end of the side form 1 of the tensioning end, the side form 2 of the middle and the side form 7 of the fixed end according to the width and height of the prestressed beam;

[0078] S22: installing the length adjusting unit 32 of the haunch beam of the haunch between the two adjacent self-adaptive U-shaped fixing clamps 31 of the haunch beam of the haunch to achieve effective fixation of the side form 4 of the haunch.

[0079] The step S21 of installing the self-adaptive U-shaped fixing clamp 31 of the haunch beam at the end of the side form 1 of the tensioning end, the side form 2 of the middle and the side form 7 of the fixed end according to the width and height of the prestressed beam includes the following steps:

[0080] S211: sleeving the first large head end 311 on the first small head end 312, adjusting the depth of the first large head end 311 sleeved on the first small head end 312 according to the width of the prestressed beam; sleeving the second large head end 313 on the second small head end 314, adjusting the depth of the second large head end 313 sleeved on the second small head end 314 according to the height of the prestressed beam, realizing the self-adaptation of the prestressed beam with different width and height;

[0081] S212: using the tensioning screw 301 and the locking nut 316 to fix the two prestressed beam height adjusting units in the appropriate position;

[0082] Further, the step S22 of installing the length adjusting unit 32 of the haunch beam of the haunch between the two adjacent self-adaptive U-shaped fixing clamps 31 of the haunch beam of the haunch according to the length of the side form 4 of the haunch includes:

[0083] S221: sleeving the large head end 321 of the square tube on the small head end 322 of the square tube, adjusting the insertion depth between the two according to the length of the haunch of the haunch beam, ensuring that the length adjusting unit 32 of the haunch beam of the haunch can adapt to the side form 4 of the haunch and the haunch beam 9 of different sizes;

[0084] S222: connecting the U-shaped clamp lug 302 on the self-adaptive U-shaped fixing clamp 31 of the haunch beam with the square tube lug 323 on the length adjusting unit 32 of the haunch beam of the haunch, using the bolt 324 to fix the square tube lug 323 with the U-shaped clamp lug 302, realizing the fixation of the length adjusting unit 32 of the haunch beam of the haunch on the side of the side form 4 of the haunch, ensuring the stability of the side form 4 of the haunch and preventing displacement during the concrete pouring process.

[0085] Further, the step S3 of installing the tensioning end prestressed tendon installation assembly 5 on the side form 1 of the tensioning end includes:

[0086] A clamping anchor 51 is installed on the second side plate 12 of the tensioning end side mold 1, close to the side where the first side plate 11 is located, to ensure its accurate position and alignment with the tensioning direction of the prestressed tendon 8;

[0087] A first pressure plate 52 is installed on the clamping anchor 51, close to the side where the intermediate side mold 2 is located, to ensure that it can withstand force during tensioning;

[0088] A first spiral tendon 53 is installed on the first pressure plate 52, close to the side where the intermediate side mold 2 is located, to ensure that it can provide sufficient friction during tensioning.

[0089] In step S3, the fixed end prestressed tendon installation assembly 6 is installed on the fixed end side mold 7, including:

[0090] A second pressure plate 61 is installed on the fixed end side mold 7, close to the side where the intermediate side mold 2 is located, and an extrusion anchor 63 is installed on the side away from the intermediate side mold 2, to ensure that their center lines are collinear and aligned;

[0091] A second spiral tendon 62 is installed on the side of the second pressure plate 61 away from the extrusion anchor 63, to ensure that it can provide sufficient friction during tensioning.

[0092] In step S3, the two ends of the prestressed tendon 8 are fixed with the tensioning end prestressed tendon installation assembly 5 and the fixed end prestressed tendon installation assembly 6, respectively, including:

[0093] The tensioning end of the prestressed tendon is passed through the first spiral tendon 53, the first pressure plate 52, and the clamping anchor 51, to ensure that the tensioning end of the prestressed tendon 8 is fixed in the clamping anchor 51;

[0094] The fixed end of the prestressed tendon 8 is passed through the second spiral tendon 62 and the second pressure plate 61, and then fixed in the extrusion anchor 63.

[0095] Further, in step S4, the fixed support of the prestressed tendon 8 is set according to the design drawing to ensure the curve positioning of the prestressed tendon 8. When there is a conflict with ordinary reinforcement or other pipelines, the position of the prestressed tendon 8 should be ensured first.

[0096] Further, in step S5, the concrete behind the tensioning end pad must be vibrated during the vibrating process to prevent accidents during tensioning, but the prestressed tendon should not be touched with a vibrating rod for a long time to prevent damage to the outer PE layer. The concrete curing of the prestressed beam should be strengthened to prevent early shrinkage cracks before tensioning. Stress control and strain checking methods should be used during prestressed tendon tensioning. On-site prestress records should be well maintained during construction. All prestressed beam supports must be removed after the prestressed tendon tensioning is completed.

[0097] Further, after the prestressed tendon tensioning in step S6 is completed, end sealing work must be strictly done, the excess steel strands can be cut by using a grinding wheel, the length of the remaining exposed steel strands is not less than 30mm, and electric arc cutting is strictly prohibited.

[0098] The application improves the bearing capacity and anti-cracking performance of the concrete structure by using the haunched beam slow-bonding prestressing technology; the application of the prestress to the steel bars in advance makes the concrete in a compression state under the load, thereby enhancing the overall performance of the structure; the application can be applied to the construction of large and complex prestressed beam structures; the design of the haunched beam can more effectively disperse the load and improve the stability of the structure; the application of the slow-bonding technology can reduce the fluidity and deformation of the concrete in the construction process, and help to ensure the position stability of the prestressed tendon; the application is simple to construct, combines the traditional prestressing technology with the modern concrete technology, has a simple construction process, and is easy to operate.

[0099] Those skilled in the art will easily understand that the above description is only the preferred embodiment of the present application, and is not intended to limit the present application, and any modification, equivalent replacement and improvement made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A concrete support structure based on beam haunching and slow-bonded prestressing, characterized in that: The prestressed beam is made of a tension end side mold (1), a fixed end side mold (7), an intermediate side mold (2), a haunch side mold (4) for adding a haunch at the end of the prestressed beam, a haunch beam haunch side mold fixing mechanism (3) for fixing the haunch side mold (4), a tension end prestressed tendon installation assembly (5) provided on the tension end side mold (1) and a fixed end prestressed tendon installation assembly (6) provided on the fixed end side mold (7), and a prestressed tendon (8) provided between the tension end prestressed tendon installation assembly (5) and the fixed end prestressed tendon installation assembly (6). The intermediate side mold (2) is provided between the tension end side mold (1) and the fixed end side mold (7); the haunch beam haunch side mold fixing mechanism (3) includes a haunch beam self-adaptive U-shaped fixing clamp (31) provided at the haunch end of the tension end side mold (1), the fixed end side mold (7) and the intermediate side mold (2) respectively, and a plurality of haunch beam haunch length adjusting units (32) provided in parallel and spaced apart from top to bottom between adjacent two haunch beam self-adaptive U-shaped fixing clamps (31); the tension end side mold (1) includes first and second side plates (11, 12) arranged in parallel and spaced apart; the intermediate side mold (2) includes third and fourth side plates (21, 22) arranged in parallel and spaced apart; the haunch side mold (4) is provided between the first and third side plates (11, 21); different haunch beam self-adaptive U-shaped fixing clamps (31) fix the first and second side plates (11, 12) as a whole and fix the third and fourth side plates (21, 22) as a whole; the haunch beam self-adaptive U-shaped fixing clamp (31) includes a prestressed beam width adjusting unit and a prestressed beam height adjusting unit provided vertically at both ends of the prestressed beam width adjusting unit; the haunch beam self-adaptive U-shaped fixing clamp (31) is adjusted to adapt to prestressed beams of different widths and heights; the haunch side mold (4) is arranged between the tension end side mold (1) and the intermediate side mold (2) and between the intermediate side mold (2) and the fixed end side mold (7); the haunch beam haunch length adjusting unit (32) is adjusted to adapt to the haunch side mold (4) of different lengths, thereby realizing the haunch of the prestressed beam; and the prestressed beam end side haunch provides an operable space for the tension end when the slow-bonding prestressed tendon is tensioned.

2. The concrete support structure based on beam haunching and slow-bonded prestress according to claim 1, characterized in that: The tension end prestressed tendon installation assembly (5) includes a clamping piece anchor (51), a first pressure receiving plate (52) and a first spiral tendon (53) provided on the side of the tension end side mold (1). The centers of the clamping piece anchor (51) and the first pressure receiving plate (52) are collinear. The clamping piece anchor (51) is provided on the side of the second side plate (12) close to the first side plate (11). The first pressure receiving plate (52) is provided on the side of the clamping piece anchor (51) away from the second side plate (12). The first spiral tendon (53) is provided on the side of the first pressure receiving plate (52) away from the clamping piece anchor (51). The tension end of the prestressed tendon (8) passes through the first spiral tendon (53), the first pressure plate (52), the clamping anchor (51) and the second side plate (12) in turn and extends to the other side of the second side plate (12); The fixed end of the prestressed tendon (8) is fixed with the fixed end side mold (7) through the fixed end prestressed tendon installation assembly (6).

3. A concrete support structure based on beams with haunches and prestressed with slow bonds according to claim 2, characterized in that: The fixed end prestressed tendon installation assembly (6) comprises a second pressure plate (61) arranged on the fixed end side mold (7) near one side of the intermediate side mold (2), a second spiral tendon (62), and an extrusion anchor (63) arranged on the fixed end side mold (7) away from one side of the intermediate side mold (2); The centers of the second pressure plate (61) and the extrusion anchor (63) are collinear, and are arranged on opposite sides of the formwork of the fixed end side mold (7); The second spiral tendon (62) is arranged on the side of the second pressure plate (61) away from the extrusion anchor (63); The fixed end of the prestressed tendon (8) passes through the second spiral tendon (62), the second pressure plate (61), the formwork of the fixed end side mold (7) and the extrusion anchor (63) in turn and is fixed.

4. A concrete support structure based on beams with haunches and prestressed with slow bonds according to any one of claims 1-3, characterized in that: The prestressed tendon (8) comprises a steel strand, a slow-bonding adhesive coated on the steel strand, and an outer PE layer arranged outside the slow-bonding adhesive. The outer PE layer is provided with uneven indentations on the surface.

5. A concrete support structure based on beams with haunches and prestressed with slow bonds according to any one of claims 1-3, characterized in that: The self-adaptive U-shaped fixed clamp (31) of the haunched beam is provided with a tension screw (301) and a U-shaped clamp lug (302); the U-shaped clamp lugs (302) are arranged on the side of the prestressed beam height adjusting unit in a uniform and spaced manner.

6. A concrete support structure based on beams with haunches and prestressed with slow bonds according to claim 5, characterized in that: The prestressed beam width adjusting unit comprises a first large head end (311) and a first small head end (312) arranged in a movable plug-in manner. The prestressed beam height adjusting unit comprises a second large head end (313) and a second small head end (314) arranged in a movable plug-in manner from top to bottom; The second large head ends (313) and the second small head ends (314) on both sides are provided with adjusting grooves (315) penetrating from top to bottom; the lengths and positions of the adjusting grooves (315) on both sides correspond to each other; The plug-in depth of the first large head end (311) and the first small head end (312) is adjusted to adapt to prestressed beams of different widths; the plug-in depth of the second large head end (313) and the second small head end (314) is adjusted synchronously to adapt to prestressed beams of different heights; The two ends of the tension screw (301) pass through the adjusting grooves (315) on both sides, and the two prestressed beam height adjusting units are fixed by a locking nut (316).

7. A concrete support structure based on beams with haunches and prestressed with slow bonds according to claim 6, characterized in that: The haunch length adjusting unit (32) of the haunched beam comprises a plurality of groups of square tube large head ends (321) and square tube small head ends (322) arranged in a movable plug-in manner; the square tube large head ends (321) and the square tube small head ends (322) are respectively provided with square tube lugs (323) at the ends away from each other. The number and position of the square tube lifting ears (323) are adapted to the U-shaped clamping ears (302); the square tube lifting ears (323) at both ends of the axillary beam and axillary length adjustment unit (32) are fixed to the U-shaped clamping ears (302) at corresponding positions by means of latches (324), thereby achieving the fixation of the axillary beam and axillary length adjustment unit (32) on the side of the axillary side mold (4); and the insertion depth of the square tube large end (321) and the square tube small end (322) is adjusted to adapt to axillary side molds (4) and axillary beams (10) of different sizes.

8. A construction method of a beam haunch based retarded prestressed concrete, characterized by, The concrete support structure based on beam haunches and slow-bonded prestressing according to any one of claims 1 to 7 is used for implementation, comprising the following steps: S1: Install the tensioning end side form (1), the fixed end side form (7), and the middle side form (2) in the construction area according to the design requirements; install the armpit side form (4) at the armpit portion between the tensioning end side form (1), the middle side form (2), and the fixed end side form (7), ensuring that the armpit ends of each side form fit tightly together; S2: Installing an axillary beam and axillary side mold fixing mechanism (3) on the side of the axillary side mold (4); S3: Installing the tensioning end prestressed tendon installation assembly (5) on the tensioning end side form (1), installing the fixed end prestressed tendon installation assembly (6) on the fixed end side form (7), and fixing the two ends of the prestressed tendon (8) to the tensioning end prestressed tendon installation assembly (5) and the fixed end prestressed tendon installation assembly (6), respectively; S4: fixing brackets are arranged at intervals on the prestressed tendons (8) to position the prestressed tendons (8) in a curved manner; S5: Pour concrete. When the concrete reaches 85% of the design strength, remove the beam side formwork and tension and anchor the prestressed tendons. S6: After the prestressed tendons are tensioned and anchored, cut off the exposed excess prestressed tendons; clean the tensioning end and its surroundings, seal the tensioning end with micro-expanding fine stone concrete of the same grade and vibrate it to make it dense, thus completing the production of the slow-bonding prestressed concrete structure based on beam plus armpit.

9. The construction method of a slow-bonded prestressed concrete based on the haunch of a beam according to claim 8, characterized in that, In step S2, an armpit beam and armpit side mold fixing mechanism (3) is installed on the side of the armpit side mold (4), comprising: S21: installing adaptive U-shaped fixing clips (31) for the axillary beam at the ends of the axillary portions of the tensioning end side form (1), the middle side form (2), and the fixed end side form (7) according to the width and height of the prestressed beam; S22: According to the length of the axillary side formwork (4), the axillary beam length adjustment unit (32) is respectively installed between two adjacent axillary beam adaptive U-shaped fixing clamps (31) to achieve effective fixation of the axillary side formwork (4); ensuring that the axillary side formwork (4) is stable and does not shift during the concrete pouring process.

10. The construction method of a slow bond prestressed concrete based on the beam haunching according to claim 8, characterized in that, The step S3 of installing the tensioning end prestressed tendon installation assembly (5) on the tensioning end side form (1) includes: Installing a clip anchor (51) on the second side plate (12) of the tensioning end side form (1) near the side where the first side plate (11) is located, ensuring that the clip anchor (51) is accurately positioned and aligned with the tensioning direction of the prestressed tendon (8); Installing a first pressure plate (52) on the side of the clip anchor (51) close to the middle side mold (2); The first spiral rib (53) is installed on the first pressure plate (52) near the side of the middle side mold (2); The step S3 of installing the fixed end prestressed tendon installation assembly (6) on the fixed end side mold (7) comprises: The second pressure plate (61) is installed on the fixed end side mold (7) near the side of the middle side mold (2), and the extrusion anchor (63) is installed away from the middle side mold (2), so that the center lines of them are collinear and aligned; The second spiral rib (62) is installed on the side of the second pressure plate (61) away from the extrusion anchor (63); The step S3 of fixing the two ends of the prestressed tendon (8) to the tension end prestressed tendon installation assembly (5) and the fixed end prestressed tendon installation assembly (6) respectively comprises: The tension end of the prestressed tendon passes through the first spiral rib (53), the first pressure plate (52) and the clip anchor (51), so that the tension end of the prestressed tendon (8) is fixed in the clip anchor (51); The fixed end of the prestressed tendon (8) passes through the second spiral rib (62) and the second pressure plate (61), and then is fixed in the extrusion anchor (63).

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