A UHPC precast column and its installation process

Abstract

The present invention provides a UHPC precast column, which includes a column body, a steel bar framework arranged in the column body, and a grouting sleeve arranged in the column body. The steel bar framework includes a plurality of outer main steel bars longitudinally penetrating through the column body. At the center of the grouting sleeve, an upper insertion hole for the outer main steel bars to pass through, a rebar connecting cavity communicated with the upper insertion hole, and a lower insertion hole communicated with the rebar connecting cavity and for longitudinally reserved steel bars to pass through are successively arranged from top to bottom. On the side wall of the grouting sleeve, a grouting pipe with a pipe orifice flush with the side wall of the column body and communicated with the rebar connecting cavity, and an overflow pipe with a pipe orifice flush with the side wall of the column body and communicated with the rebar connecting cavity are provided. A plurality of grouting sleeves are pre-embedded in the column body of this UHPC precast column. Since the outer main steel bars are inserted into the rebar connecting cavity and the longitudinally reserved steel bars are inserted into the rebar connecting cavity, when the concrete slurry in the rebar connecting cavity hardens, the outer main steel bars of the precast column and the longitudinally reserved steel bars of the bearing platform can be connected together, which is beneficial to improving the connection strength between the bearing platform and this UHPC precast column.

Description

Technical Field

[0001] The present invention relates to the technical field of building structures, and in particular to a UHPC precast column and its installation process. Background Art

[0002] Ultra-high performance concrete, abbreviated as UHPC (Ultra-High Performance Concrete), also known as reactive powder concrete, is the most innovative cement-based engineering material in the past thirty years. Ultra-high performance concrete includes two aspects of "ultra-high": ultra-high durability and ultra-high mechanical properties. UHPC can be regarded as the engineering material with the best durability. The mechanical properties of UHPC members with appropriate reinforcement are close to those of steel structures. At the same time, UHPC members have excellent wear resistance and explosion resistance. Therefore, UHPC members are particularly suitable for long-span bridges, explosion-resistant structures (commonly used in bank vaults, etc.), and thin-walled structures, as well as in highly abrasive and corrosive environments. At present, UHPC members have been applied in some practical projects, such as long-span pedestrian bridges, highway and railway bridges, prefabricated structures, etc.

[0003] The prefabricated structure is short for prefabricated reinforced concrete structure, which is a reinforced concrete structure mainly composed of prefabricated components connected by assembly. The prefabricated structure is one of the important directions for the development of building structures in China. It is beneficial to the development of China's building industrialization, improves production efficiency, saves energy, develops green and environmental protection buildings, and is also beneficial to improving and ensuring the quality of building projects. At present, the prefabricated concrete frame structures widely promoted and constructed mainly adopt the assembled monolithic concrete frame connected by the superposed cast-in-place method. The main components include precast beams, precast columns, precast exterior wall panels, precast interior wall partitions, precast floor slabs, precast balcony slabs, precast air-conditioning slabs, precast stairs, etc.

[0004] At present, the specific installation process of installing a precast column on a pile cap is as follows: Pour a pile cap on the top of a pile foundation. Longitudinal reserved steel bars protruding from the surface of the pile cap are embedded in the pile cap. Then, a crane hoists the precast column. When the precast column is hoisted directly above the pile cap, workers check whether the longitudinal reserved steel bars of the pile cap are aligned with the steel bar sockets at the bottom of the precast column. After the longitudinal reserved steel bars of the pile cap are aligned with the steel bar sockets at the bottom of the precast column, the crane slowly lowers the precast column so that the longitudinal reserved steel bars of the pile cap are inserted into the steel bar sockets at the bottom of the precast column, then the connection positioning work between the pile cap and the precast column is completed. Then, pour concrete into the splicing joint reserved between the surface of the pile cap and the bottom surface of the precast column. After the concrete hardens, the pile cap and the precast column are connected as a whole. Although the above installation scheme can install the precast column on the pile cap, the connection strength between the precast column and the pile cap is relatively low. Summary of the Invention

[0005] The problem to be solved by the present invention is to provide a UHPC prefabricated column and an installation process thereof in view of the above-mentioned deficiencies existing in the prior art, which solves the problem of low connection strength between the prefabricated column and the pedestal existing in the prior art.

[0006] The above-mentioned inventive object of the present invention is achieved through the following technical scheme: a UHPC prefabricated column, comprising a column body, a steel bar skeleton arranged in the column body, and a grouting sleeve arranged in the column body, wherein the steel bar skeleton comprises a plurality of outer main bars longitudinally penetrated in the column body, and the center of the grouting sleeve is provided with an upper plug hole for the outer main bars to pass through, a bar connection cavity connected to the upper plug hole, and a lower plug hole connected to the bar connection cavity and used for the longitudinal reserved steel bars to pass through, and a grouting pipe whose pipe mouth is flush with the side wall of the column body and connected to the bar connection cavity, and an overflow pipe whose pipe mouth is flush with the side wall of the column body and connected to the bar connection cavity are provided on the side wall of the grouting sleeve.

[0007] The present invention is further configured as follows: the steel skeleton also includes stirrups for tightening multiple external main bars, internal main bars located in the inner circle of the external main bars, multiple long tension bars that simultaneously hook the external main bars and stirrups, multiple short tension bars that simultaneously hook the stirrups, external main bars, internal main bars and long tension bars, and multiple diagonal bracing tension bars arranged in the stirrup circle.

[0008] The present invention is further configured as follows: a reinforcement locking device is provided at one end of the grouting sleeve close to the upper plug hole, and the reinforcement locking device includes a shell, and the shell includes an upper seat body, a lower seat body, a connecting head plugged with the upper plug hole, and a reinforcement hole that passes through the upper seat body, the lower seat body, and the connecting head in sequence from top to bottom; a movable groove is provided on the end surface of the connecting head away from the lower seat body, a sliding hole connected to the reinforcement hole is provided on the groove wall of the movable groove, a reinforcement clamping head is slidably arranged in the sliding hole, and a driving mechanism for controlling the reinforcement clamping head to clamp the outer main reinforcement is provided in the shell.

[0009] The invention is further configured as follows: an upper mounting groove is provided on the end surface of the upper seat body facing the lower seat body, and a lower mounting groove is provided on the end surface of the lower seat body facing the upper seat body, a tooth groove located on the inner ring of the lower mounting groove and connected to the lower mounting groove, and a mounting hole connected to the movable groove is provided at the groove bottom of the tooth groove, and the driving mechanism comprises a bevel gear disk rotatably arranged in the lower mounting groove and whose inner ring surface is a gear ring, a plurality of bevel gear shafts arranged in the shell and meshing with the bevel gear disk, a transmission gear arranged in the tooth groove and meshing with the gear ring, a transmission shaft coaxially arranged on the end surface of the transmission gear facing the mounting hole and passing through the mounting hole, and a four-corner cam coaxially arranged at one end of the transmission shaft passing through the mounting hole, and a spring groove connected to the sliding hole is provided on the groove wall of the movable groove, and a force plate is provided at one end of the clamp head close to the four-corner cam, and a push plate spring is provided in the spring groove to push the force plate tightly against the four-corner cam wheel surface.

[0010] The present invention is further configured as follows: a guide groove is provided on the wheel surface of the four-corner cam, and a guide sheet extending into the guide groove and slidingly cooperating with the bottom of the guide groove is provided on the end surface of the force-bearing plate facing the four-corner cam.

[0011] The present invention is further configured as follows: a spline shaft is provided at one end of the transmission shaft away from the transmission gear, a tightening threaded hole is provided on the end surface of the spline shaft facing away from the transmission shaft, a spline hole that is plugged into and fits with the spline shaft is provided at the center of the four-corner cam, and the tightening threaded hole is threadedly connected with a tightening screw that tightens the four-corner cam onto the transmission shaft.

[0012] The present invention is further configured as follows: an outer rotating hole and a bearing groove which are connected to the upper mounting groove and the lower mounting groove and are half-opened on the upper seat body and the lower seat body are sequentially formed on the outer side wall of the shell; an inner rotating hole which is half-opened on the upper seat body and the lower seat body is formed on the inner groove wall of the upper mounting groove and the lower mounting groove; the bevel gear shaft includes an outer shaft body which is rotatably matched with the outer rotating hole, a bevel gear which is arranged in the upper mounting groove and the lower mounting groove and meshes with the bevel gear disk, and an inner shaft body which is rotatably matched with the inner rotating hole; an adjustment hole is formed on the end surface of the outer shaft body which is away from the bevel gear; and a bearing which is sleeved on the outer shaft body is embedded in the bearing groove.

[0013] The present invention is further configured as follows: a card slot is provided on the hole wall of the upper jack, an annular groove connected to the movable groove and used to align with the card slot is provided on the outer wall of the connector, and a plurality of card rings are provided in the annular groove which are pushed by the four-corner cam and partially slide into the card slot.

[0014] The present invention is further configured as follows: a plurality of connecting threaded holes are provided on the end surface of the connecting head away from the lower seat body, an annular pressure plate is provided on the end surface of the connecting head away from the lower seat body for pressing the retaining ring into the annular groove, a plurality of countersunk holes aligned with the connecting threaded holes are provided on the end surface of the annular pressure plate away from the connecting head, and countersunk screws threadedly connected to the connecting threaded holes are provided in the countersunk holes.

[0015] A UHPC prefabricated column installation process, the installation process comprising the following steps:

[0016] Step 1: Correct the skewed longitudinal reserved steel bars, trim the overlong longitudinal reserved steel bars, then use the steel bar positioning steel plate with measuring holes to check the position and verticality of the longitudinal reserved steel bars, and then use a tape measure to check the reserved length of the longitudinal reserved steel bars, re-correct the deviated longitudinal reserved steel bars, and re-trim the overlong longitudinal reserved steel bars until the construction requirements are met;

[0017] Step 2: Roughen the surface of the cap, then clear the obstacles on the surface of the cap, and then mark the measurement and positioning control axis and prefabricated column positioning edge line on the surface of the cap according to the preset construction drawings;

[0018] Step 3: Measure the level height of the pedestal surface, and place shims on the pedestal surface to level the lifting plane according to the measured data. Then use a level to check the elevation of each shim, and replace the shims that do not meet the elevation requirements until all shims meet the elevation requirements.

[0019] Step 4: Before the lifting construction, the signalman confirms the safety around the prefabricated column. Under the condition of ensuring safety, the crane slowly lifts the prefabricated column. When the prefabricated column is lifted to 0.4~0.6 meters above the ground, under the condition of ensuring that the lifting sling is firmly connected, the crane continues to lift the prefabricated column to 0.4~0.6 meters above the pedestal. The installation worker checks the positioning edge line of the prefabricated column and the position of the prefabricated column, and uses a mirror to observe whether the longitudinal reserved steel bar and the lower plug hole are aligned. After the longitudinal reserved steel bar and the lower plug hole are correctly aligned, the prefabricated column is slowly lowered to make the longitudinal reserved steel bar pass through the lower plug hole and insert into the connection cavity. At the same time, the prefabricated column falls on the gasket and is placed firmly in place;

[0020] Step 5: Install multiple sets of inclined supports on each face of the prefabricated column to temporarily fix the prefabricated column, then use a crowbar to move the prefabricated column, and use a plumb bob and a ruler to correct the position and verticality of the prefabricated column. At the same time, use a theodolite to check the horizontal positioning, elevation and verticality of the prefabricated column. After checking and adjusting, tighten the inclined supports and remove the lifting ring on the top of the prefabricated column.

[0021] Step 6: A casting template with a grouting hole is set on the side wall of the precast column to enclose the joint into a closed space, and then the grouting pipe of the grouting machine is inserted into the grouting hole for grouting. When the grouting pressure of the grouting machine reaches the preset standard, the grouting hole is sealed with a plug. After the concrete slurry hardens, the casting template is removed;

[0022] Step 7: Workers use electric grouting pumps to send concrete slurry into the reinforcement cavity through the grouting pipe. After the concrete slurry flows out of the overflow pipe, seal the overflow pipe with a plug and continue grouting into the reinforcement cavity until the grouting pressure of the electric grouting pump reaches the preset standard. Then, stop grouting and seal the grouting pipe with a plug. Repeat the above operation several times to complete the grouting work of all grouting sleeves in turn. After the concrete slurry in the reinforcement cavity hardens, pull out all the plugs.

[0023] In summary, the beneficial technical effects of the present invention are:

[0024] (1) A plurality of grouting sleeves are embedded in the column body of the UHPC precast column. Since the outer main reinforcement of the precast column passes through the upper insertion hole of the grouting sleeve and is inserted into the reinforcement cavity, and the longitudinal reserved reinforcement of the cap passes through the lower insertion hole of the grouting sleeve and is inserted into the reinforcement cavity, when the concrete slurry in the reinforcement cavity hardens, the outer main reinforcement of the precast column and the longitudinal reserved reinforcement of the cap can be connected together, which is beneficial to improve the connection strength between the cap and the UHPC precast column;

[0025] (2) By arranging a steel bar locking device on this UHPC precast column to clamp and position the external main steel bars, during the binding process of the steel bar framework, relative movement between the external main steel bars and the grouting sleeve is not likely to occur, which is beneficial to improving the installation accuracy between the external main steel bars and the grouting sleeve, and can also improve the binding accuracy of the steel bar framework. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 is the longitudinal sectional structure diagram of the UHPC precast column and the bearing platform in the present invention;

[0027] Figure 2 is the transverse sectional structure diagram of the UHPC precast column in the present invention;

[0028] Figure 3 is the longitudinal sectional structure diagram of the steel bar locking device in the present invention;

[0029] Figure 4 is the transverse sectional structure diagram of the steel bar locking device in the present invention;

[0030] Figure 5 is Figure 4 the enlarged view of part A in

[0031] Figure 6 is the exploded view of the steel bar locking device from the first perspective in the present invention;

[0032] Figure 7 is the exploded view of the steel bar locking device from the second perspective in the present invention;

[0033] Figure 8 is the structural schematic diagram of the steel bar locking device in the present invention;

[0034] Figure 9 is the structural schematic diagram of the steel bar locking device in the present invention.

[0035] In the above-mentioned drawings: 1, bearing platform; 2, longitudinally reserved steel bars; 3, column body; 4, outer main steel bars; 5, stirrups; 6, long tension bars; 7, inner main steel bars; 8, short tension bars; 9, inclined bracing tension bars; 10, grouting sleeve; 11, upper socket; 111, card slot; 12, steel bar connecting cavity; 13, lower socket; 14, grouting pipe; 15, overflow pipe; 16, upper seat body; 17, lower seat body; 18, connector; 19, steel bar passing hole; 20, movable slot; 21, spring slot; 22, sliding hole; 23, steel bar clamping head; 24, stress plate; 25, push plate spring; 26, guiding piece; 27, upper installation slot; 28, lower installation slot; 29, tooth slot; 30, installation hole; 31, outer rotation hole; 32, bearing slot; 33, inner rotation hole; 34, bevel gear disk; 341, gear ring; 35, bevel gear shaft; 351, outer shaft body; 352, bevel gear; 353, inner shaft body; 36, bearing; 37, adjusting hole; 38, driving gear; 39, transmission shaft; 40, spline shaft; 41, pressing threaded hole; 42, four-corner cam; 43, spline hole; 44, pressing screw; 45, guiding groove; 46, annular groove; 47, snap ring; 48, connecting threaded hole; 49, annular pressing plate; 50, counterbore; 51, countersunk head screw. Detailed implementation manners

[0036] In order to make the technical means, creative features, achieved purposes and functions of the present invention clearer and easier to understand, the present invention will be further described below in conjunction with the drawings and specific implementation manners.

[0037] As Figure 1 shown, the precast column is installed on the bearing platform 1. The bearing platform 1 refers to a reinforced concrete platform arranged at the top of the pile foundation to bear and distribute the loads transmitted by the precast column, and longitudinally reserved steel bars 2 extending out of the surface of the bearing platform 1 are embedded in the bearing platform 1.

[0038] As Figure 1 and 2 shown, the present invention provides a UHPC precast column, which includes a column body 3 formed by concrete pouring, a steel bar framework arranged in the column body 3, and a grouting sleeve 10 arranged in the column body 3.

[0039] As Figure 1 and 2As shown in the figure, the steel bar framework includes outer main bars 4, stirrups 5, long tension bars 6, inner main bars 7, short tension bars 8, and diagonal bracing bars 9. The length direction of the outer main bars 4 is the same as that of the column body 3, that is, the outer main bars 4 are longitudinally inserted into the column body 3. The outer main bars 4 are threaded steel bars. In this embodiment, the number of the outer main bars 4 is thirty-six, and the thirty-six outer main bars 4 are distributed in a rectangular shape. Then, nine outer main bars 4 are arranged on the inner side of each face of the column body 3. The stirrups 5 surround all the outer main bars 4. The stirrups 5 are arranged at equal intervals along the longitudinal direction of the column body 3. A plurality of stirrups 5 are used to connect the outer main bars 4 into one body. The stirrups 5 and the outer main bars 4 are connected by welding at the connection points. In this embodiment, the number of the long tension bars 6 in each cross-section of the precast column is four. The four long tension bars 6 are arranged perpendicular to each other in pairs. The long tension bars 6 simultaneously hook the outer main bars 4 and the stirrups 5. The long tension bars 6 and the outer main bars 4, the stirrups 5 are connected by welding at the connection points. The long tension bars 6 are used to improve the structural strength of this UHPC precast column.

[0040] As Figure 1 and 2 shown in the figure, the length direction of the inner main bars 7 is the same as that of the column body 3, that is, the inner main bars 7 are longitudinally inserted into the column body 3. The inner main bars 7 are threaded steel bars. In this embodiment, the number of the inner main bars 7 is twenty, and the twenty inner main bars 7 are distributed in a rectangular shape. The inner main bars 7 are used to improve the structural strength of this UHPC precast column. In this embodiment, the number of the short tension bars 8 in each cross-section of the precast column is eight. The short tension bars 8 simultaneously hook the stirrups 5, the outer main bars 4, the inner main bars 7, and the long tension bars 6. The short tension bars 8 and the stirrups 5, the outer main bars 4, the inner main bars 7, the long tension bars 6 are connected by welding at the connection points. The short tension bars 8 are used to improve the structural strength of this UHPC precast column. In this embodiment, the number of the diagonal bracing bars 9 in each cross-section of the precast column is four. The four diagonal bracing bars 9 are arranged inside the circle of the stirrups 5. The four diagonal bracing bars 9 are all inclined. The diagonal bracing bars 9 are used to improve the structural strength of this UHPC precast column.

[0041] As Figure 1As shown in the figure, in this embodiment, the number of grouting sleeves 10 is thirty-six, and the grouting sleeves 10 are arranged at the bottom of each external main reinforcement 4. An upper jack 11, a reinforcement connecting cavity 12, and a lower jack 13 are successively formed in the center of the grouting sleeve 10 from top to bottom. The upper jack 11 is used for the external main reinforcement 4 to pass through. The upper jack 11 is a circular hole, and an annular clamping groove 111 is formed on the hole wall of the upper jack 11. The cross-section of the reinforcement connecting cavity 12 is circular, and the diameter of the reinforcement connecting cavity 12 is larger than that of the upper jack 11. The external main reinforcement 4 and the longitudinally reserved reinforcement 2 are connected within the reinforcement connecting cavity 12. The lower jack 13 is used for the longitudinally reserved reinforcement 2 to pass through, and the lower jack 13 is a circular hole. A grouting pipe 14 and an overflow pipe 15 are fixedly connected to the side wall of the grouting sleeve 10. The overflow pipe 15 is located directly above the grouting pipe 14. The pipe orifice of the grouting pipe 14 is flush with the side wall of the column body 3, and the grouting pipe 14 is communicated with the reinforcement connecting cavity 12. The pipe orifice of the overflow pipe 15 is flush with the side wall of the column body 3, and the overflow pipe 15 is communicated with the reinforcement connecting cavity 12.

[0042] As Figure 3 and 6 shown, a locking reinforcement device is arranged at one end of the grouting sleeve 10 close to the upper jack 11. The locking reinforcement device includes a housing, and the housing includes an upper seat body 16, a lower seat body 17, and a connecting head 18 successively arranged from top to bottom. The upper seat body 16, the lower seat body 17, and the connecting head 18 are all cylindrical. The upper seat body 16 is screwed to the end face of the lower seat body 17 facing away from the connecting head 18. The upper seat body 16 and the lower seat body 17 have the same diameter. The connecting head 18 is integrally connected to the end face of the lower seat body 17 facing away from the upper seat body 16. The diameter of the connecting head 18 is smaller than that of the lower seat body 17. The connecting head 18 is in plug-in fit with the upper jack 11. A reinforcement passing hole 19 is formed in the center of the housing and successively penetrates through the upper seat body 16, the lower seat body 17, and the connecting head 18. The reinforcement passing hole 19 is a circular hole.

[0043] As Figure 4 and 5 shown, a movable groove 20 is formed on the end face of the connecting head 18 facing away from the lower seat body 17. In this embodiment, the number of movable grooves 20 is three, and the three movable grooves 20 are evenly distributed in a circumferential manner. Spring grooves 21 and sliding holes 22 are successively formed on the groove wall of each movable groove 20. The sliding holes 22 communicate with the reinforcement passing hole 19. The sliding holes 22 are circular holes. The spring grooves 21 are circular grooves, and the diameter of the spring grooves 21 is larger than the aperture of the sliding holes 22. A clamping reinforcement head 23 is slidably arranged in the sliding holes 22. The clamping reinforcement head 23 is bullet-shaped, and a driving mechanism for pushing the clamping head out of the sliding hole 22 to clamp the external main reinforcement 4 is arranged in the housing

[0044] As Figure 4 and 5As shown, one end of the rib clamping head 23 away from the rib passing hole 19 is fixedly connected with a force receiving plate 24. A push plate spring 25 is arranged in the spring groove 21. The push plate spring 25 is sleeved on the rib clamping head 23. One end of the push plate spring 25 abuts against the bottom of the spring groove 21, and the other end abuts against the force receiving plate 24. The push plate spring 25 is used to push the force receiving plate 24 to move away from the rib passing hole 19. A guiding piece 26 is fixedly connected to the end face of the force receiving plate 24 away from the rib clamping head 23. The cross section of the guiding piece 26 is a rectangle plus a semicircle.

[0045] As Figure 3 and 6 As shown, an upper mounting groove 27 is formed on the end face of the upper seat body 16 facing the lower seat body 17, and a lower mounting groove 28 is formed on the end face of the lower seat body 17 facing the upper seat body 16. The upper mounting groove 27 and the lower mounting groove 28 are aligned. A tooth groove 29 is formed on the end face of the lower seat body 17 facing the upper seat body 16. The number of the tooth grooves 29 is three. The three tooth grooves 29 are equally spaced in a circumferential distribution. The three tooth grooves 29 are all communicated with the lower mounting groove 28. An installation hole 30 is formed at the bottom of each tooth groove 29. The installation hole 30 is a circular hole. One end of the installation hole 30 away from the tooth groove 29 is communicated with the movable groove 20.

[0046] As Figure 6 and 7 As shown, an outer rotation hole 31 and a bearing groove 32 are sequentially formed on the outer side wall of the housing. The outer rotation hole 31 is a circular hole. The outer rotation hole 31 is formed on the upper seat body 16 and the lower seat body 17 in a split manner. The bearing groove 32 is a circular groove. The bearing groove 32 is formed on the upper seat body 16 and the lower seat body 17 in a split manner. The number of the outer rotation holes 31 and the bearing grooves 32 is three. The three outer rotation holes 31 and the three bearing grooves 32 are all equally spaced in a circumferential distribution. Inner rotation holes 33 are formed on the inner groove walls of the upper mounting groove 27 and the lower mounting groove 28. The inner rotation holes 33 are located inside the upper mounting groove 27 and the lower mounting groove 28. The inner rotation holes 33 are circular holes. The inner rotation holes 33 are formed on the upper seat body 16 and the lower seat body 17 in a split manner.

[0047] As Figure 6 and 7As shown in the figure, the driving mechanism includes a bevel gear disk 34, a bevel gear shaft 35, a transmission gear 38, a transmission shaft 39, and a four-corner cam 42. The bevel gear disk 34 is rotatably arranged in the lower mounting groove 28, and the inner ring surface of the bevel gear disk 34 is a toothed ring 341. The bevel gear shaft 35 includes an outer shaft body 351, a bevel gear 352, and an inner shaft body 353 that are coaxially and integrally connected. The outer shaft body 351 is rotationally matched with the outer rotation hole 31, and a bearing 36 sleeved on the outer shaft body 351 is embedded in the bearing groove 32. An adjustment hole 37 is formed on the end surface of the outer shaft body 351 facing away from the bevel gear 352. The adjustment hole 37 is a rectangular hole and is used for plugging and matching with the head of an electric four-corner wrench. The bevel gear 352 is located in the upper mounting groove 27 and the lower mounting groove 28, and the bevel gear 352 meshes with the bevel gear disk 34. Rotating the bevel gear 352 can drive the bevel gear disk 34 to rotate, and the inner shaft body 353 is rotationally matched with the inner rotation hole 33.

[0048] As Figure 3 and 6 shown in the figure, the transmission gear 38 is rotatably arranged in the tooth groove 29, the transmission gear 38 meshes with the toothed ring 341 of the bevel gear disk 34, and the rotation of the bevel gear disk 34 will drive the transmission gear 38 to rotate. The transmission shaft 39 is integrally and coaxially arranged on the end surface of the transmission gear 38 facing the mounting hole 30. The transmission shaft 39 passes through the mounting hole 30, and the transmission shaft 39 is rotationally matched with the mounting hole 30.

[0049] As Figure 8 and 9 shown in the figure, a spline shaft 40 is integrally and coaxially arranged on the end surface of the transmission shaft 39 away from the transmission gear 38. A pressing threaded hole 41 is formed on the end surface of the spline shaft 40 facing away from the transmission shaft 39. The four-corner cam 42 is arranged at one end of the transmission shaft 39 away from the transmission gear 38. A spline hole 43 for plugging and matching with the spline shaft 40 is formed at the center of the four-corner cam 42. A pressing screw 44 for pressing the four-corner cam 42 onto the transmission shaft 39 is threadedly connected to the pressing threaded hole 41. The four-corner cam 42 has two long protrusions farther from the center point and two short protrusions closer to the center point. A guiding groove 45 is formed on the wheel surface of the four-corner cam 42. The guiding piece 26 extends into the guiding groove 45, and the guiding piece 26 is slidably matched with the bottom of the guiding groove 45.

[0050] As Figure 5 and 7 shown in the figure, an annular groove 46 is formed on the outer side wall of the connector 18. The cross-section of the annular groove 46 is an annular shape, and the annular groove 46 communicates with the three movable grooves 20. The annular groove 46 is used for aligning with the clamping groove 111. Three clamping rings 47 are slidably arranged in the annular groove 46. The clamping rings 47 are fan-shaped rings, and the three clamping rings 47 are equidistantly distributed in a circumferential manner. The three clamping rings 47 can form a complete ring. When the long protrusion of the four-corner cam 42 abuts against the inner wall of the clamping ring 47, the four-corner cam 42 will push the clamping ring 47 to partially slide into the clamping groove 111.

[0051] As Figure 5 and 7 shown, three connecting threaded holes 48 are formed on the end face of the connecting head 18 facing away from the lower seat body 17. The three connecting threaded holes 48 are equidistantly distributed in a circumferential manner. An annular pressing plate 49 is arranged on the end face of the connecting head 18 facing away from the lower seat body 17. The annular pressing plate 49 is circular in shape, and its hollow part is used for the outer main reinforcement 4 to pass through. The annular pressing plate 49 is used to press the snap ring 47 tightly in the annular groove 46. Then, when the snap ring 47 is not driven by an external force, the snap ring 47 is not easy to move in the annular groove 46. A plurality of countersunk holes 50 aligned with the connecting threaded holes 48 are formed on the end face of the annular pressing plate 49 facing away from the connecting head 18. Countersunk screws 51 threadedly connected to the connecting threaded holes 48 are arranged in the countersunk holes 50.

[0052] The detailed working process of this embodiment is as follows:

[0053] The worker inserts the connecting head 18 of the steel bar locking device into the upper insertion hole 11 of the grouting sleeve 10. At this time, the annular groove 46 is aligned with the clamping groove 111. Then, the outer main reinforcement 4 is passed through the steel bar passing hole 19 of the steel bar locking device and inserted into the steel bar connecting cavity 12 of the grouting sleeve 10. Then, the worker inserts the head of the electric four-way wrench into the adjustment hole 37 of the bevel gear shaft 35 and starts the electric four-way wrench. Then, the electric four-way wrench will drive the bevel gear shaft 35 to rotate a preset angle, and then will drive the bevel gear 352, the transmission gear 38, the transmission shaft 39, and the four-way cam 42 to rotate accordingly. When the guiding piece 26 slides to the long protrusion of the four-way cam 42, the four-way cam 42 will push the guiding piece 26, the force receiving plate 24, and the steel bar clamping head 23 to move towards the direction close to the steel bar passing hole 19. Then, the steel bar clamping head 23 will slide out of the sliding hole 22 and clamp the outer main reinforcement 4. At the same time, the long protrusion of the four-way cam 42 abuts against the inner wall of the snap ring 47, and the four-way cam 42 will push the snap ring 47 to partially slide into the clamping groove 111. Then, the steel bar locking device is restricted from separating from the grouting sleeve 10.

[0054] A plurality of grouting sleeves 10 are pre-embedded in the column body 3 of this UHPC precast column. Since the outer main reinforcement 4 of the precast column passes through the upper insertion hole 11 of the grouting sleeve 10 and is inserted into the steel bar connecting cavity 12, and the longitudinal reserved steel bar 2 of the bearing platform 1 passes through the lower insertion hole 13 of the grouting sleeve 10 and is inserted into the steel bar connecting cavity 12. Then, when the concrete slurry in the steel bar connecting cavity 12 hardens, the outer main reinforcement 4 of the precast column and the longitudinal reserved steel bar 2 of the bearing platform 1 can be connected together, which is beneficial to improving the connection strength between the bearing platform 1 and this UHPC precast column.

[0055] This UHPC precast column clamps and positions the outer main reinforcement 4 by setting a steel bar locking device. Then, during the binding process of the steel bar cage, the relative movement between the outer main reinforcement 4 and the grouting sleeve 10 is not easy to occur, which is beneficial to improving the installation accuracy between the outer main reinforcement 4 and the grouting sleeve 10, and can also improve the binding accuracy of the steel bar cage.

[0056] The present invention also provides an installation process for a UHPC precast column, and the installation process includes the following steps:

[0057] Step 1: Rectify the skewed longitudinal reserved steel bars 2, trim the overlong longitudinal reserved steel bars 2, then use a steel bar positioning steel plate with a measurement hole to recheck the position and perpendicularity of the longitudinal reserved steel bars 2, and then use a tape measure to recheck the reserved length of the longitudinal reserved steel bars 2. Rectify the misaligned longitudinal reserved steel bars 2 again and trim the overlong longitudinal reserved steel bars 2 again until the construction requirements are met.

[0058] In the above Step 1, the worker first rectifies the skewed longitudinal reserved steel bars 2 and trims the overlong longitudinal reserved steel bars 2, and then rechecks the position, length and perpendicularity of the longitudinal reserved steel bars 2 until the longitudinal reserved steel bars 2 can meet the construction requirements. In this way, it can effectively avoid the problem that the grouting sleeve 10 in the precast column cannot be correctly connected due to the misalignment of the longitudinal reserved steel bars 2 and the incorrect reserved length of the longitudinal reserved steel bars 2.

[0059] Step 2: Chip the surface of the bearing platform 1, then clean the obstacles on the surface of the bearing platform 1, and then mark the measurement positioning control axis and the precast column positioning side line on the surface of the bearing platform 1 according to the preset construction drawings.

[0060] In the above Step 2, measurement and setting out is a commonly used technical means in the construction field, and the specific operation process of measurement and setting out will not be elaborated here. The marked measurement positioning control axis and the precast column positioning side line are used to facilitate the worker to position the precast column during the precast column hoisting construction.

[0061] Step 3: Measure the level height of the surface of the bearing platform 1, and place shims on the surface of the bearing platform 1 for leveling the hoisting plane according to the measurement data. Then use a level to recheck the elevation of each shim and replace the shims that do not meet the elevation requirements until all the shims meet the elevation requirements.

[0062] In the above Step 3, taking the precast column positioning side line as the reference, place shims at the four corners of the precast column positioning side line and level the elevation. The shims are used to level the surface of the bearing platform 1 so that the precast column can be placed stably on the shims, and it is also convenient to adjust the position and perpendicularity of the precast column.

[0063] Step 4: Before hoisting construction, the signalman confirms the safety conditions around the precast column. When ensuring safety, the crane slowly hoists the precast column. When the precast column is hoisted to a height of 0.4 - 0.6 meters above the ground, and ensuring the firm connection of the hoisting slings, the crane continues to hoist the precast column to a height of 0.4 - 0.6 meters above the bearing platform 1. The installer aligns the positioning side line of the precast column and the position of the precast column, and uses a mirror to observe whether the longitudinal reserved steel bars 2 and the lower socket holes 13 are aligned. After the longitudinal reserved steel bars 2 and the lower socket holes 13 are correctly aligned, slowly lower the precast column so that the longitudinal reserved steel bars 2 pass through the lower socket holes 13 and insert into the connection cavity. At the same time, the precast column lands on the gasket and is placed stably.

[0064] In the said Step 4, the worker needs to confirm the safety conditions around the precast column and ensure the firm connection of the hoisting slings before proceeding with the next hoisting operation, which can effectively reduce the probability of safety accidents during the hoisting of the precast column; adopting the method of lowering the precast column in sections facilitates the worker to complete the alignment operation of the longitudinal reserved steel bars 2 and the lower socket holes 13; using a mirror to observe whether the longitudinal reserved steel bars 2 and the lower socket holes 13 are aligned can, to a certain extent, avoid the problem of workers putting their heads under the precast column to observe whether the longitudinal reserved steel bars 2 and the lower socket holes 13 of the grouting sleeve 10 are correctly aligned, which is beneficial to protecting the safety of workers and avoiding safety accidents to a certain extent.

[0065] Step 5: Install multiple groups of inclined supports on each surface of the precast column to temporarily fix the precast column. Then, use a crowbar to move the precast column, and use a plumb bob and a straightedge to correct the position and verticality of the precast column. At the same time, use a theodolite to check the horizontal positioning, elevation, and verticality of the precast column. After checking and adjusting without error, tighten the inclined supports and remove the lifting rings at the top of the precast column.

[0066] In the said Step 5, each group of inclined supports includes a long inclined support and a short inclined support. The long inclined support and the short inclined support in the same group are coplanar, and both the long inclined support and the short inclined support are temporarily fixed on the side surface of the precast column; during construction, use a crowbar to move the precast column, and use a plumb bob and a straightedge to correct the position and verticality of the precast column. At the same time, adjust the positions of the long inclined support and the short inclined support to adapt to the adjustment of the precast column. Then, use a theodolite to check the horizontal positioning, elevation, and verticality of the precast column. After checking and adjusting without error, use expansion bolts to tighten all the inclined supports. Use multiple groups of inclined supports to position the precast column so that the precast column does not displace when pouring the splicing joint and grouting the grouting sleeve 10.

[0067] Step 6: Set up a casting formwork on the side wall of the precast column to enclose the splicing joint into a sealed space and having a grouting hole. Then, insert the grouting pipe 14 of the grouting machine into the grouting hole for grouting. When the grouting pressure of the grouting machine reaches the preset standard, plug the grouting hole with a plug. After the concrete slurry hardens, remove the casting formwork.

[0068] In step 6, the casting formwork is a flat formwork, and the number of casting formworks is four. The four casting formworks enclose the splicing joint into a closed space. Workers use a nail gun to fix the four casting formworks on the four sides of the precast column respectively. Then, insert the grouting pipe 14 of the grouting machine into the grouting hole and conduct grouting. When the grouting pressure of the grouting machine reaches the preset standard, plug the grouting hole. In this embodiment, the plug is selected as a wooden plug. Then, according to the preset construction standard, wait for the concrete slurry in the splicing joint to harden, and then the casting formwork can be removed.

[0069] Step 7: Workers use an electric grouting pump to send the concrete slurry into the rebar connecting cavity 12 through the grouting pipe 14. After the concrete slurry flows out of the overflow pipe 15, plug the overflow pipe 15 with a plug, and continue to grout into the rebar connecting cavity 12 until the grouting pressure of the electric grouting pump reaches the preset standard, then stop grouting and plug the grouting pipe 14 with a plug. Repeat the above operations multiple times to complete the grouting work of all grouting sleeves 10 in sequence. After the concrete slurry in the rebar connecting cavity 12 hardens, pull out all the plugs.

[0070] In step 7, the concrete slurry needs to be prepared according to the construction standard. The specific preparation process is as follows: First, prepare a mixing container, mixing tools, and the raw materials of the concrete slurry. Second, determine the mixing quantity of the grouting material each time according to the initial setting time and grouting speed of the grouting material. During construction, since the external main reinforcement 4 of the precast column passes through the upper insertion hole 11 of the grouting sleeve 10 and inserts into the rebar connecting cavity 12, and the longitudinal reserved reinforcement 2 of the bearing platform 1 passes through the lower insertion hole 13 of the grouting sleeve 10 and inserts into the rebar connecting cavity 12, after the above grouting work is completed and the concrete slurry in the rebar connecting cavity 12 hardens, the external main reinforcement 4 of the precast column and the longitudinal reserved reinforcement 2 of the bearing platform 1 can be connected together.

[0071] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit. Although the present invention has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that the technical solutions of the present invention can be modified or equivalently replaced without departing from the purpose and scope of the technical solutions of the present invention, and they should all be covered within the scope of the claims of the present invention.

Claims

1. A UHPC precast column, characterized in that: it comprises a column body (3), a steel bar framework arranged in the column body (3), and a grouting sleeve (10) arranged in the column body (3). The steel bar framework includes a plurality of outer main steel bars (4) longitudinally penetrating through the column body (3). The upper socket (11) for the outer main steel bars (4) to pass through, a rebar connecting cavity (12) communicated with the upper socket (11), and a lower socket (13) communicated with the rebar connecting cavity (12) and for the longitudinal reserved steel bars (2) to pass through are successively opened from top to bottom at the center of the grouting sleeve (10). A grouting pipe (14) with its pipe orifice flush with the side wall of the column body (3) and communicated with the rebar connecting cavity (12), and an overflow pipe (15) with its pipe orifice flush with the side wall of the column body (3) and communicated with the rebar connecting cavity (12) are arranged on the side wall of the grouting sleeve (10); the steel bar framework further includes stirrups (5) for clamping a plurality of outer main steel bars (4), inner main steel bars (7) located inside the outer main steel bars (4), a plurality of long tension bars (6) simultaneously hooking the outer main steel bars (4) and the stirrups (5), a plurality of short tension bars (8) simultaneously hooking the stirrups (5), the outer main steel bars (4), the inner main steel bars (7) and the long tension bars (6), and a plurality of diagonal bracing bars (9) arranged inside the stirrups (5); a steel bar locking device is arranged at one end of the grouting sleeve (10) close to the upper socket (11). The steel bar locking device includes a housing, and the housing includes an upper seat body (16), a lower seat body (17), a connecting head (18) inserted and matched with the upper socket (11), and a rebar passing hole (19) successively penetrating through the upper seat body (16), the lower seat body (17) and the connecting head (18). An activity groove (20) is opened on the end surface of the connecting head (18) facing away from the lower seat body (17). A sliding hole (22) communicated with the rebar passing hole (19) is opened on the groove wall of the activity groove (20). A clamping bar head (23) is slidably arranged in the sliding hole (22). A driving mechanism for controlling the clamping bar head (23) to clamp the outer main steel bar (4) is arranged in the housing; An upper mounting groove (27) is provided on the end surface of the upper seat body (16) facing the lower seat body (17); a lower mounting groove (28) is provided on the end surface of the lower seat body (17) facing the upper seat body (16); a tooth groove (29) is located in the inner ring of the lower mounting groove (28) and is connected to the lower mounting groove (28); a mounting hole (30) is provided at the bottom of the tooth groove (29) and is connected to the movable groove (20); the driving mechanism comprises a bevel gear plate (34) rotatably arranged in the lower mounting groove (28) and having an inner ring surface as a gear ring (341); a plurality of bevel gear shafts (35) arranged in the housing and meshing with the bevel gear plate (34); and a tooth groove (29) is provided in the tooth groove (29). 9) and meshing with the gear ring (341), a transmission shaft (39) coaxially arranged on the end face of the transmission gear (38) facing the mounting hole (30) and passing through the mounting hole (30), and a four-corner cam (42) coaxially arranged on one end of the transmission shaft (39) passing through the mounting hole (30), a spring groove (21) connected to the sliding hole (22) is opened on the groove wall of the movable groove (20), a force plate (24) is arranged at one end of the clamp head (23) close to the four-corner cam (42), and a push plate spring (25) is arranged in the spring groove (21) to push the force plate (24) against the wheel surface of the four-corner cam (42).

2. A UHPC prefabricated column according to claim 1, Features: A guide groove (45) is provided on the wheel surface of the four-corner cam (42), and a guide piece (26) is provided on the end surface of the force-bearing plate (24) facing the four-corner cam (42), which extends into the guide groove (45) and slides with the bottom of the guide groove (45).

3. A UHPC prefabricated column according to claim 1, Features: A spline shaft (40) is arranged at one end of the transmission shaft (39) away from the transmission gear (38); a clamping threaded hole (41) is provided on the end surface of the spline shaft (40) away from the transmission shaft (39); a spline hole (43) plug-fitting with the spline shaft (40) is provided at the center of the four-corner cam (42); and a clamping screw (44) is threadedly connected to the clamping threaded hole (41) for clamping the four-corner cam (42) onto the transmission shaft (39).

4. A UHPC prefabricated column according to claim 1, Features: The outer wall of the housing is provided with an outer rotating hole (31) and a bearing groove (32) which are connected to the upper mounting groove (27) and the lower mounting groove (28) and are opened in half on the upper seat body (16) and the lower seat body (17). The inner groove wall of the upper mounting groove (27) and the lower mounting groove (28) is provided with an inner rotating hole (33) which is opened in half on the upper seat body (16) and the lower seat body (17). The bevel gear shaft (35) includes a bearing groove (32) which is connected to the outer rotating hole ( An outer shaft body (351) rotatably matched with the bevel gear (31), a bevel gear (352) arranged in the upper mounting groove (27) and the lower mounting groove (28) and meshing with the bevel gear plate (34), and an inner shaft body (353) rotatably matched with the inner rotating hole (33), an adjustment hole (37) is opened on the end surface of the outer shaft body (351) away from the bevel gear (352), and a bearing (36) mounted on the outer shaft body (351) is embedded in the bearing groove (32).

5. A UHPC prefabricated column according to claim 1, Features: The end surface of the connecting head (18) facing away from the lower seat body (17) is provided with a plurality of connecting threaded holes (48); the end surface of the connecting head (18) facing away from the lower seat body (17) is provided with an annular pressure plate (49) for pressing the retaining ring (47) into the annular groove (46); the end surface of the annular pressure plate (49) facing away from the connecting head (18) is provided with a plurality of countersunk holes (50) aligned with the connecting threaded holes (48); the countersunk holes (50) are provided with countersunk screws (51) threadedly connected to the connecting threaded holes (48).

6. A UHPC prefabricated column according to any one of claim 1, Features: A clamping groove (111) is provided on the hole wall of the upper plug hole (11), and an annular groove (46) is provided on the outer side wall of the connector (18) and is communicated with the movable groove (20) and used to align with the clamping groove (111). A plurality of clamping rings (47) are provided in the annular groove (46) and are pushed by the four-corner cam (42) and partially slide into the clamping groove (111).

7. A UHPC prefabricated column installation process according to any one of claims 1 to 6, Features: The installation process comprises the following steps: Step 1: correct the deflected longitudinal reserved steel bars (2), trim the overlong longitudinal reserved steel bars (2), then use a steel bar positioning steel plate with measuring holes to check the position and verticality of the longitudinal reserved steel bars (2), then use a tape measure to check the reserved length of the longitudinal reserved steel bars (2), re-correct the deflected longitudinal reserved steel bars (2), and re-trim the overlong longitudinal reserved steel bars (2) until the construction requirements are met; Step 2: roughening the surface of the cap (1), then clearing obstacles on the surface of the cap (1), and then marking the measurement and positioning control axis and the prefabricated column positioning edge line on the surface of the cap (1) according to the preset construction drawings; Step 3: Measure the level height of the surface of the bearing platform (1), and place shims on the surface of the bearing platform (1) for leveling the hoisting plane according to the measurement data. Then, use a level to recheck the elevation of each shim, and replace the shims that do not meet the elevation requirements until all shims meet the elevation requirements; Step 4: Before hoisting construction, the signalman confirms the safety conditions around the precast column. When ensuring safety, the crane slowly hoists the precast column. When the precast column is hoisted to a height of 0.4 - 0.6 meters above the ground, and ensuring the firm connection of the hoisting slings and rigging, the crane continues to hoist the precast column to a height of 0.4 - 0.6 meters above the bearing platform (1). The installer checks the positioning edge line and the position of the precast column, and uses a mirror to observe whether the longitudinal reserved steel bars (2) and the lower socket holes (13) are aligned. After the longitudinal reserved steel bars (2) and the lower socket holes (13) are correctly aligned, slowly lower the precast column so that the longitudinal reserved steel bars (2) pass through the lower socket holes (13) and are inserted into the connection cavity, and at the same time, the precast column lands on the shims and is placed stably; Step 5: Install multiple groups of inclined supports on each surface of the precast column to temporarily fix the precast column. Then, use a crowbar to move the precast column, and use a plumb bob and a straightedge to correct the position and verticality of the precast column. At the same time, use a theodolite to check the horizontal positioning, elevation and verticality of the precast column. After checking and adjusting without errors, tighten the inclined supports and remove the lifting rings at the top of the precast column; Step 6: Set up a pouring formwork on the side wall of the precast column that encloses the splicing joint into a closed space and has grouting holes. Then, insert the grouting pipe (14) of the grouting machine into the grouting holes for grouting. When the grouting pressure of the grouting machine reaches the preset standard, plug the grouting holes with plugs. After the concrete slurry hardens, remove the pouring formwork; Step 7: The worker uses an electric grouting pump to send the concrete slurry into the reinforcement connection cavity (12) through the grouting pipe (14). After the concrete slurry flows out from the overflow pipe (15), plug the overflow pipe (15) with a plug, and continue to grout into the reinforcement connection cavity (12) until the grouting pressure of the electric grouting pump reaches the preset standard, then stop grouting and plug the grouting pipe (14) with a plug. Repeat steps 1 - 7 multiple times to complete the grouting work of all grouting sleeves (10) in sequence. After the concrete slurry in the reinforcement connection cavity (12) hardens, pull out all the plugs.

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