Rock-fill dam cantilever overturning and lifting device

Abstract

The invention relates to the technical field of concrete construction formworks, provides a rockfill dam cantilever overturning and lifting device, and solves the problem of long assembly and disassembly time caused by design defects of an existing device. The invention comprises: a template; the back frame is mounted on the first surface of the template and is used for bearing a load from the template; the cantilever frame is mounted below the back frame; the connecting piece comprises a U-shaped piece, a limiting block, a grouting sleeve, a fixing nut and a fixing block, the U-shaped piece is arranged on the second face of the formwork, the limiting block is arranged at one end of the grouting sleeve, the limiting block is arranged in the U-shaped piece in a sliding mode, a plurality of grouting holes are formed in the outer side of the grouting sleeve, the grouting holes are formed downwards in an inclined mode, and the fixing nut is arranged in the U-shaped piece. The connecting piece has an unpoured state and a poured state; one end of the tie bar is provided with a bent section, and the bent section is hung on the U-shaped piece; the embedded part is embedded in the top of the poured concrete layer, and the other end of the tie bar is connected with the embedded part.

Description

Technical Field

[0001] The present invention relates to the technical field of concrete construction formwork, and particularly to a cantilever lifting device for a rockfill dam. Background Art

[0002] With the continuous development of construction engineering technology, the cantilever lifting formwork technology, as an advanced construction method, has been widely applied in various construction projects. Especially in the construction of large formwork concrete pouring, the cantilever lifting formwork technology plays an indispensable role. The cantilever lifting formwork is a formwork technology based on the principle of cantilever force, which has the advantages of fast construction speed, strong adaptability, and good economy. Through the lifting operation of the formwork, the continuous pouring of vertical concrete structures can be realized, improving the construction efficiency and quality. In addition, the cantilever lifting formwork technology also has a wide range of applications in the fields of bridges, hydraulic engineering, and underground engineering.

[0003] Chinese Patent Publication No. CN105971271A discloses a unilateral self-climbing cantilever formwork. The unilateral self-climbing cantilever formwork includes a self-climbing formwork frame and a unilateral cantilever formwork. The unilateral cantilever formwork is installed on the self-climbing formwork frame. In this invention, tie rod embedments are used to connect the unilateral cantilever formwork to the already poured concrete layer. However, due to the weak shear resistance of the tie rod embedments, a high density of tie rod embedments needs to be set to avoid construction accidents, which will increase a large amount of installation and dismantling working hours. Summary of the Invention

[0004] Therefore, in view of the above problems, the present invention provides a cantilever lifting device for a rockfill dam to solve the problem of long installation and dismantling working hours caused by design defects in existing devices.

[0005] To achieve the above object, the present invention is realized through the following technical solutions: A cantilever lifting device for a rockfill dam, comprising: A formwork, the bottom of which has a fitting part with the already poured concrete layer; A back frame, installed on the first surface of the formwork. The back frame and the formwork have a plurality of connection points, and the back frame is used to bear the load from the formwork; A cantilever frame, installed below the back frame; A connecting piece, wherein the connecting piece comprises a U-shaped piece, a limit block, a grouting sleeve, a fixing nut and a fixing block, wherein the U-shaped piece is arranged on the second surface of the template, the limit block is arranged at one end of the grouting sleeve, the limit block is slidably arranged in the U-shaped piece, a plurality of grouting holes are arranged on the outer side of the grouting sleeve, each of the grouting holes is opened obliquely downward, the connecting piece has an uncast state and a cast state, in the uncast state, both ends of the U-shaped piece pass through the template and are connected to the fixing nut, in the cast state, the fixing block is locked to the end of the U-shaped piece by the fixing nut, a clamping groove is arranged on the top of the fixing block, a receiving cavity is arranged on one side of the cantilever frame, and a clamping sheet matching the clamping groove is arranged on one side of the receiving cavity; A tie rod, wherein one end of the tie rod is provided with a bent section, the bent section is hung on the U-shaped member, and the tie rod is arranged obliquely downward; The embedded part is embedded in the top of the poured concrete layer, and the other end of the tie bar is connected to the embedded part.

[0006] Furthermore, the connecting member also includes a wedge block, and the wedge block is sleeved on one end of the limiting block.

[0007] Furthermore, the embedded part includes an anchor bar and a conical sleeve, the conical sleeve is arranged on the outside of the anchor bar, and one end of the anchor bar is in a hook shape.

[0008] Furthermore, arc grooves are provided on both sides of the limit block, and the U-shaped member is inserted into the arc grooves.

[0009] Furthermore, the back frame adopts a truss structure, and the number of trusses n and the template span L satisfy the following relationship: When L≤3m, n≥L; When L>3m, n≥2L.

[0010] Furthermore, the matching relationship between the number a of the tie bars and the template span L is: a=2×L / 3, where L is in m, a is the number of tie bars arranged along the height direction of the template, and the tensile strength of a single tie bar is not less than 150kN.

[0011] Furthermore, the height h of the fitting portion 1 ≥200mm, the distance between the connecting piece and the top of the template is h 2 , the h 2 =h 1 +50mm.

[0012] Furthermore, a one-way stop is provided on the edge of the template, and adjacent templates are engaged and connected by bolts.

[0013] Furthermore, the distance between the two ends of the U-shaped member is 8-16 cm.

[0014] Compared with the prior art, the beneficial effects of the present invention are as follows: 1. The prestress generated by the locking of the tension bars and the formwork in the present invention can actively offset the shrinkage stress during the solidification of concrete, reduce the generation of structural cracks, and increase the bonding strength between the connecting members and the layers.

[0015] 2. The present invention can fix the tension bars through the sliding fit of the limiting block and the U-shaped member, avoiding the inclination of the tension bars during the pouring of the concrete layer.

[0016] 3. By connecting the connecting member with the cantilever frame, the present invention can increase the setting spacing of the connecting members, thereby reducing the installation and removal working hours.

[0017] 4. Through the inclined grouting holes of the grouting sleeve in the present invention, grouting can be selectively carried out after the concrete layer solidifies according to the working conditions, improving the strength of the connection node and increasing the shear strength of a single connecting member. Description of the Drawings

[0018] Figure 1 Schematic diagram of the structure of the first layer of concrete not poured in the embodiment of the present invention; Figure 2 Schematic diagram of the structure of the (N + 1)-th layer of concrete not poured in the embodiment of the present invention; Figure 3 Schematic diagram of the structure of the (N + 1)-th layer of concrete poured in the embodiment of the present invention; Figure 4 Schematic diagram of the structure of the engagement between the engaging piece and the engaging groove in the embodiment of the present invention; Figure 5 Top view structure schematic diagram of the connecting member in the embodiment of the present invention; Figure 6 Cross-sectional structure schematic diagram of the connecting member in the embodiment of the present invention; Figure 7 Schematic diagram of the one-way rabbet structure in the embodiment of the present invention; Figure 8 For Figure 1 Enlarged structure schematic diagram at A in Figure 9 For Figure 1 Enlarged structure schematic diagram at B in Figure 10 For Figure 3 Enlarged structure schematic diagram at C in

[0019] Explanation of the reference numerals in the drawings: Formwork 1; One-way rabbet 11; Back frame 2; Cantilever frame 3; Accommodation cavity 31; Engaging piece 32; Connecting member 4; U-shaped member 41; Limiting block 42; Arc groove 421; Grouting sleeve 43; Fixing nut 44; Fixing block 45; Engaging groove 451; Grouting hole 46; Lacing bar 5; Bent section 51; Embedded part 6; Anchor bar 61; Conical sleeve 62. Specific implementation mode

[0020] The following will combine specific embodiments to detail the implementation mode of the present invention, so as to fully understand how the present invention applies technical means to solve technical problems and the implementation process of achieving technical effects and implement accordingly.

[0021] Embodiment

[0022] As Figures 1 to 10 shown, a cantilever lifting device for a rockfill dam includes: a formwork 1, the bottom of which has a fitting part with the already poured concrete layer; a back frame 2, installed on the first surface of the formwork 1, the back frame 2 and the formwork 1 having a plurality of connection points, the back frame 2 being used to bear the load from the formwork; a cantilever frame 3, installed below the back frame 2; a connecting piece 4, the connecting piece 4 including a U-shaped piece 41, a limiting block 42, a grouting sleeve 43, a fixing nut 44 and a fixing block 45, the U-shaped piece 41 being arranged on the second surface of the formwork 1, one end of the grouting sleeve 43 being provided with the limiting block 42, the limiting block 42 being slidably arranged in the U-shaped piece 41, a plurality of grouting holes 46 being arranged on the outer side of the grouting sleeve 43, each of the grouting holes 46 being obliquely downwardly opened, the connecting piece 4 having an un-poured state and a poured state, in the un-poured state, both ends of the U-shaped piece 41 pass through the formwork 1 and are connected to the fixing nut 44, in the poured state, the fixing block 45 is locked to the end of the U-shaped piece 41 through the fixing nut 44, a clamping groove 451 being arranged on the top of the fixing block 45, a receiving cavity 31 being arranged on one side of the cantilever frame 3, and a clamping piece 32 matching the clamping groove 451 being arranged on one side of the receiving cavity 31; a lacing bar 5, one end of the lacing bar 5 being provided with a bent section 51, the bent section 51 being hung on the U-shaped piece 41, the lacing bar 5 being obliquely downwardly arranged; an embedded part 6, embedded in the top of the already poured concrete layer, and the other end of the lacing bar 5 being connected to the embedded part 6.

[0023] The present application does not specifically limit the number of the grouting holes 46, which is adjusted according to the actual situation.

[0024] In other preferred embodiments, in order to strengthen the fixing effect of the limiting block 42 on the lacing bar 5, a notch (not shown in the figure) is arranged on the side of the limiting block 42 close to the lacing bar.

[0025] Arc-shaped grooves 421 are arranged on both sides of the limiting block 42, and the U-shaped piece 41 is arranged in the arc-shaped grooves 421, that is, both sides of the limiting block 42 are recessed inward, and the U-shaped piece 41 is arranged in the recesses, so as to prevent the limiting block 42 from laterally separating from the U-shaped piece 41 without additional on-site assembly.

[0026] In other preferred embodiments, the connecting member 4 further includes a wedge block (not shown in the figure). The wedge block is sleeved on one end of the grouting sleeve 43. A through groove matching the outer side of the grouting sleeve 43 is provided on the wedge block 43. The grouting sleeve 43 is inserted into the through groove. One side of the wedge block away from the grouting sleeve 43 is an inclined surface for contacting the tie bar 5, which can fix the inclination angle of the tie bar 5. In this embodiment, no embedded part 6 is provided, that is, one end of the tie bar 5 is connected to the connecting member 4 and the other end is a free end. This situation is applicable to small-span formworks 1 or when the density of the connecting members 4 is high.

[0027] The embedded part 6 includes an anchor bar 61 and a conical sleeve 62. The conical sleeve 62 is arranged outside the anchor bar 61. One end of the anchor bar 61 is in a hook shape, and the end of the anchor bar 61 with the hook shape protrudes from the top of the cast concrete. In this embodiment, both ends of the tie bar 5 are provided with bent sections 51. When setting the tie bar 5, one end of the tie bar 5 is first hooked with the anchor bar 61, then the other end of the tie bar 5 is hooked with the U-shaped member 41, and finally the U-shaped member 41 is fixed on the formwork 1.

[0028] The back frame 2 adopts a truss structure. The number of bays n of the truss and the span L of the formwork 1 satisfy the following relationship: When L ≤ 3m, n ≥ L; When L > 3m, n ≥ 2L.

[0029] In this embodiment, the formwork 1 is 3m × 3m, and the back frame 2 adopts a two-bay truss structure.

[0030] The matching relationship between the number a of the tie bars 5 and the span L of the formwork 1 is: a = 2 × L / 3, where the unit of L is m, a is the number of tie bars arranged along the height direction of the formwork 1, and the tensile strength of a single tie bar 5 is not less than 150 kN.

[0031] In this embodiment, the number of the tie bars 5 is 2.

[0032] The height h of the fitting part 1 = 200 mm. The distance between the connecting member 4 and the top of the formwork 1 is h 2 The h 2 = 250 mm. When the primary concrete layer is poured, after the primary concrete layer is poured and solidified, the cantilever frame 3 has not been installed below the back frame 2. After the primary concrete layer is poured and solidified, the formwork 1 is lifted upward by a crane to achieve flipping. The cantilever frame 3 is installed below the back frame 2 through bolts and nuts, and the cantilever frame 3 is fixed to the concrete pouring layer through the connecting member 4, and so on for upward pouring and flipping.

[0033] A one-way stop 11 is provided at the edge of the template 1, and adjacent templates 1 are snap-connected by bolts. The snap-connection can be disassembled and reused repeatedly, and can reduce the misalignment at the joints of adjacent templates 1, thereby improving the flatness of the casting surface.

[0034] The distance between the two ends of the U-shaped member 41 is 12 cm, which ensures the single-point anti-overturning moment, and this size range is adapted to the operating space of a standard wrench, avoiding installation difficulties in a narrow space.

[0035] Although the present invention has been specifically shown and described in conjunction with the preferred embodiments, it should be understood by those skilled in the art that various changes may be made to the present invention in form and details without departing from the spirit and scope of the present invention as defined by the appended claims, all of which are within the scope of protection of the present invention.

Claims

1. A cantilever lifting device for a rockfill dam, characterized in that: include: The formwork has a bottom portion that fits the poured concrete layer; A back frame is installed on the first surface of the template, the back frame and the template have multiple connection points, and the back frame is used to bear the load from the template; a cantilever frame is installed below the back frame; a connecting piece, the connecting piece includes a U-shaped piece, a limit block, a grouting sleeve, a fixing nut and a fixing block, the U-shaped piece is arranged on the second surface of the template, the limit block is arranged at one end of the grouting sleeve, the limit block is slidably arranged in the U-shaped piece, a plurality of grouting holes are arranged on the outside of the grouting sleeve, each of the grouting holes is opened obliquely downward, and the connecting piece has an uncast state and a cast state. State, in the uncast state, both ends of the U-shaped part pass through the template and are connected to the fixing nuts. In the cast state, the fixing block is locked to the end of the U-shaped part by the fixing nuts. A clamping groove is provided on the top of the fixing block, and a receiving cavity is provided on one side of the cantilever frame. A clamping piece matching the clamping groove is provided on one side of the receiving cavity; a tie rod, one end of the tie rod is provided with a bending section, and the bending section is hung on the U-shaped part, and the tie rod is arranged obliquely downward; an embedded part, which is embedded in the top of the cast concrete layer, and the other end of the tie rod is connected to the embedded part.

2. The cantilever lifting device for rockfill dam according to claim 1, characterized in that: The connecting member also includes a wedge block, and the wedge block is sleeved on one end of the limiting block.

3. The cantilever lifting device for rockfill dam according to claim 1, characterized in that: The embedded part comprises an anchor bar and a conical sleeve, wherein the conical sleeve is arranged outside the anchor bar, and one end of the anchor bar is in a hook shape.

4. The cantilever lifting device for rockfill dam according to claim 1, characterized in that: Arc grooves are arranged on both sides of the limit block, and the U-shaped piece is passed through the arc grooves.

5. The cantilever lifting device for rockfill dam according to claim 1, characterized in that: The back frame adopts a truss structure, and the number of trusses n and the template span L satisfy the following relationship: When L≤3m, n≥L; When L>3m, n≥2L.

6. The cantilever lifting device for rockfill dam according to claim 1, characterized in that: The matching relationship between the number a of the tie bars and the template span L is: a=2×L / 3, where L is in m, a is the number of tie bars arranged along the height direction of the template, and the tensile strength of a single tie bar is not less than 150kN.

7. The cantilever lifting device for rockfill dam according to claim 1, characterized in that: The height of the fitting part h1≥200mm, the distance between the connecting piece and the top of the template is h2, and h2=h1+50mm.

8. The cantilever lifting device for rockfill dam according to claim 1, characterized in that: A one-way stop is arranged on the edge of the template, and adjacent templates are engaged and connected by bolts.

9. The cantilever lifting device for rockfill dam according to claim 1, characterized in that: The distance between the two ends of the U-shaped piece is 8-16 cm.

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