A new long-span beam string structure

Abstract

The present application relates to a kind of new long-span beam string structure, including active prestressing device, strut, steel strand, passive prestressing device, support beam;The tail end of the strut is equipped with a smooth groove surface and a second limiting bolt, which form a steel strand groove;Strut front end is connected with passive prestressing device, and passive prestressing device acts on enclosure beam;The steel strand passes through each steel strand groove, and two ends pass through the embedded sleeve pipe on enclosure beam and are connected with active prestressing device;The side surface of the strut is fixedly connected with the side surface of angle steel, the other side surface of angle steel is provided with a limiting slot hole, the first limiting bolt fixedly arranged on the strut is clamped into the limiting slot hole, the first limiting bolt can slightly slide along the limiting slot hole, the angle between the strut and enclosure beam is slightly adjusted, and the first limiting bolt simultaneously plays the role of stress and self-adapting adjustment.

Description

TECHNICAL FIELD

[0001] The present application relates to a new type of long-span beam string structure for foundation pit large-span support, belonging to the field of building construction technology, in particular to the field of foundation pit beam string technology. BACKGROUND

[0002] With the continuous advancement of urban construction, the demand for land space in cities has grown rapidly. This makes the scale of foundation pit engineering continue to expand, showing characteristics such as deepening of excavation depth, expansion of area, and more complex surrounding environment. Under the constraints of relevant laws and regulations, combined with the complex and variable surrounding environment of the construction site, pile anchor support has many difficulties in practical application. Therefore, internal support support has gradually become the main way of foundation pit support at present.

[0003] Although concrete support has the advantages of large stiffness and economical cost in foundation pit support, it also has obvious disadvantages. The construction period is long because it needs to be supported, poured with concrete and maintained for a long time, which will seriously restrict the progress of earthwork excavation; the cross-sectional size of the concrete support beam is usually large, occupying a lot of space in the foundation pit, which not only hinders the efficient operation of earthwork machinery, but also affects the construction of the main structure; such support cannot be reused and is difficult to remove, and the breaking process of high-strength concrete will generate a large amount of construction waste, accompanied by vibration influence, dust pollution and high-altitude operation risk; the design adaptability is poor, and once it is poured and formed, it cannot be adjusted, and it is difficult to effectively respond to geological mutations or design changes; the environmental performance is insufficient, and the production of cement itself is a high-energy and high-emission process, and the disposal of waste after removal also faces great pressure. The characteristics of concrete support such as rigidity and solidification are particularly disadvantageous in projects with tight schedules, limited space, strict environmental requirements or complex geological conditions. SUMMARY

[0004] The purpose of the present application is to provide a new type of long-span beam string structure, which realizes long-span beam string through a series of technical means, thereby reducing the use of steel support, reducing formwork, improving construction efficiency and reducing construction period; at the same time, the beam string and the prestress applying device are full assembly type structures, which can be easily removed and reused, improving environmental performance; through active prestress application (steel strand) and passive prestress application (jack), double prestress application is realized, improving the strength and adaptability of the beam string, which can effectively respond and adjust in the event of geological mutations or design changes; the lateral small amplitude displacement of the sliding bolt reduces local stress and further improves adaptability. In summary, the present application solves a series of problems of concrete support.

[0005] The present application specifically adopts the following technical means:

[0006] The utility model provides a new type of large span beam string structure, including active prestress device 1, strut 6, steel strand 5, passive prestress device 4, support beam 7, the tail end of strut 6 is equipped with a smooth groove face 602a and a second limit bolt 601, and both enclose a steel strand groove 602, and the front end of strut 6 is connected with passive prestress device 4, and passive prestress device 4 acts on the enclosure beam 2, steel strand 5 passes through each steel strand groove 602, and both ends pass through the embedded sleeve pipe 9 on the enclosure beam 2 and are connected with active prestress device 1, one side of strut 6 is fixedly connected with the one side of angle steel 301, and the other side of angle steel 301 is provided with a limit groove hole 301a, and the first limit bolt 302 fixedly arranged on strut 6 is clamped into the limit groove hole 301a, the first limit bolt 302 can slightly slide along the limit groove hole 301a, and strut 6 is slightly adjusted with the angle between the enclosure beam, and the first limit bolt 302 simultaneously plays the role of stress and self -adaptation adjustment.

[0007] Preferably, the smooth groove face 602a is an arc surface.

[0008] Preferably, further comprising fixed plate 10, a plurality of sliding bolts 13, the passive prestress device 4 includes jack 401, and the first piston rod 403 of jack is connected with pressure sensor 404, and pressure sensor 404 is plate-shaped, and a plurality of through holes are uniformly arranged on it, a plurality of transverse countersunk pull holes are horizontally arranged on the fixed plate 10, the sliding bolt 13 is inserted from the countersunk pull hole, sequentially passes through the fixed plate 10, the through hole and is fixedly connected with the threaded section of sliding bolt 13 using the first nut 14, the embedded reinforcing bar 11 with threaded section is embedded on the enclosure beam 2, the embedded reinforcing bar 11 passes through the opening pre-set on the fixed plate 10, and the threaded section of embedded reinforcing bar 11 is fixedly connected with the second nut 15, when the passive prestress device 4 exerts pressure, the pressure sensor 404 can slightly slide horizontally along the countersunk pull hole.

[0009] Further, the countersunk pull hole is in the structure of waist-shaped stepped hole, the bolt head of sliding bolt 13 is sunk in the waist-shaped stepped hole, and the bolt head does not protrude from the fixed plate 10.

[0010] Preferably, the passive prestress device 4 has a prestress node groove 402, two jacks 401 are arranged side by side in the prestress node groove 402, the pressure sensor 404 is round and corresponds to the jack 401 one by one, and four sliding bolts 13 are arranged on a single pressure sensor 404.

[0011] Further, the strut 6 and the prestress node groove 402 have the same width, and keep the same width in the length direction.

[0012] Preferably, the support beam 7 is supported by the stand column 8.

[0013] Preferably, the active prestress device 1 comprises a perforated jack 104 sleeved outside the steel strand 5, a first anchor 102, a second anchor 105, a guide member 103, and a clamping piece 101; the clamping piece 101 is tapered and can be inserted into the small hole of the first anchor 102 and the second anchor 105 to achieve locking; the second piston rod 104b of the perforated jack 104 faces the second anchor 105, and the tail rod 104a of the perforated jack 104 abuts against the prefabricated pier on the enclosure beam 2; the guide member 103 is a split detachable structure and is located between the perforated jack 104 and the first anchor 102, and is used for preventing the clamping piece 101 on the first anchor 102 from falling off and guiding the steel strand 5.

[0014] The present application has the following beneficial effects:

[0015] 1) Double prestress application mode, one is to actively tension the steel strand by the active prestress device to achieve prestress application, and the other is to achieve strut elongation by the passive prestress device (jack lifting) to achieve passive tension of the steel strand and then prestress application, and the effect of prestress application is better;

[0016] 2) Steel strand is used instead of steel rod as the tension component of the beam string structure, the stress of the steel strand is more balanced, a large-span beam string structure can be realized, the large-span beam string structure can provide a larger working surface for construction, obviously reduces the use of concrete supports in the foundation pit, and is convenient and fast to install and disassemble, energy-saving and environment-friendly, and saves the construction period;

[0017] 3) In the design of using the steel strand, an angle steel 301 is fixed on the strut 6, and a first limiting bolt 302 is arranged on the support beam 7, both of which can realize stress bearing, and due to single-point stress bearing, the angle of the strut 6 can also be slightly changed, and the adaptability is improved;

[0018] 4) As a preferred scheme, by arranging a countersunk pull hole on the fixed plate, the sliding bolt together with the pressure sensor can slide laterally at a small amplitude under the limitation of the countersunk pull hole, the self-adaptability is improved, and the local stress is reduced.

[0019] 5) The fixed plate, the passive prestress device, the active prestress device and other components are all assembled, can be recycled and used, do not generate construction garbage, can be replaced in time according to project changes, have strong design applicability and high flexibility. BRIEF DESCRIPTION OF DRAWINGS

[0020] Figure 1 is a schematic view of a novel large-span beam string structure.

[0021] Figure 2 is a local enlarged view of a strut part.

[0022] Figure 3 is a partial enlarged view of one passive prestressing device.

[0023] Figure 4 is an enlarged view of the back perspective of one passive prestressing device.

[0024] Figure 5 is a schematic view of the structure of the jack and prestressing node slot of the passive prestressing device.

[0025] Figure 6 is a schematic view of the connection of the passive prestressing device with the fixed plate.

[0026] Figure 7 is an enlarged view of the steel strand slot part of the tail of the strut.

[0027] Figure 8 is a schematic view of the structure of the active prestressing device.

[0028] Figure 9 is a detailed enlarged view of the installation part of the active prestressing device.

[0029] In the figure, 1. active prestressing device, 2. enclosure beam (crown beam or waist beam), 3. limiting device, 4. passive prestressing device, 5. steel strand, 6. strut, 7. support beam, 8. stand, 9. embedded sleeve, 10. fixed plate, 11. embedded anchor bar, 13. sliding bolt, 14. first nut, 15. second nut;

[0030] 101. clamping piece, 102. first anchor, 103. guide member, 104. perforated jack, 105. second anchor, 104a. top rod, 104b. second piston rod;

[0031] 301. angle steel, 302. first limiting bolt, 301a. limiting slot hole;

[0032] 401. jack, 402. prestressing node slot, 403. first piston rod, 404. pressure sensor, 405. inner hexagonal bolt;

[0033] 601. second limiting bolt, 602. steel strand slot, 602a. smooth slot surface. DETAILED DESCRIPTION

[0034] The application will be further described below in combination with the drawings and specific embodiments.

[0035] Reference Figure 1 , the embodiment introduces a large-span beam string structure, which comprises an active prestressing device 1, a strut 6, a steel strand 5, a passive prestressing device 4, a support beam 7 and several other parts.

[0036] As a function of "large span" is achieved, mainly because the use of steel strand 5 instead of ordinary foundation pit within the steel cable-stayed beam steel pull rod, the stress of steel strand 5 is more uniform, is conducive to the realization of large span cable-stayed beam, thereby reducing the use of steel support in the foundation pit.

[0037] Referring to Figure 2 and Figure 7 , the tail end of the support rod 6 is provided with a smooth groove surface 602a and a second limiting bolt 601, which form a steel strand groove 602 for the steel strand to pass through.

[0038] Referring to Figure 1 and Figure 2 , the front end of the support rod 6 is connected with the passive prestressing device 4, and the passive prestressing device 4 acts on the enclosure beam 2 (which can be a crown beam or a waist beam); the steel strand 5 passes through each steel strand groove 602, and the two ends pass through the embedded sleeve 9 on the enclosure beam 2 and are connected with the active prestressing device 1.

[0039] Referring to Figure 2 , one side of the support rod 6 is fixedly connected with one side of the angle steel 301, a limiting groove hole 301a is formed in the other side of the angle steel 301, and the first limiting bolt 302 fixedly arranged on the support rod 6 is clamped into the limiting groove hole 301a. The first limiting bolt 302 can slide in the limiting groove hole 301a, and the support rod 6 is adjusted in angle with the enclosure beam. The first limiting bolt 302 simultaneously plays a role of force bearing and self-adaptive adjustment. Here, the angle steel 301 with the limiting groove hole 301a replaces the clamp commonly used in the prior art. Compared with the clamp, the angle steel 301 has stronger force bearing capacity, and because it is single-point force bearing, combined with the sliding action of the steel strand in the steel strand groove, the support rod 6 can be self-adaptively fine-tuned in angle.

[0040] In this embodiment, as a preferred, the smooth groove surface 602a is an arc surface.

[0041] Referring to Figures 4-6 , it further comprises a fixed plate 10 and a plurality of sliding bolts 13; the passive prestressing device 4 comprises a jack 401, the first piston rod 403 of the jack is connected with a pressure sensor 404, and the pressure sensor 404 is in the form of a plate with a plurality of through holes uniformly arranged thereon; a plurality of transverse countersunk pull holes are horizontally formed on the fixed plate 10, the sliding bolts 13 are inserted from the countersunk pull holes, sequentially pass through the fixed plate 10, the through holes and are fixedly connected with the threaded segments of the sliding bolts 13 by using first nuts 14;

[0042] Continuing to refer to Figures 4-6The pre-embedded tendon 11 with a threaded section at the outer end is pre-embedded on the containment beam 2, passes through the pre-set opening on the fixed plate 10, and is fixedly connected with the threaded section of the pre-embedded tendon 11 by using a second nut 15; when the passive prestress device 4 is pressed, the pressure sensor 404 can slide laterally in a small range along the countersunk tension hole. In this way, the self-adjusting ability of the passive prestress device can be improved, the local stress can be reduced, the adaptability can be improved, and the structural stability of the large-span beam string structure is beneficial.

[0043] Specifically, the countersunk tension hole is in the structure of a waist-shaped stepped hole, the bolt head of the sliding bolt 13 is sunk in the waist-shaped stepped hole, and the bolt head does not protrude from the fixed plate 10. Please refer to the attached Figure 4 However, the structure in the stepped hole is not shown in detail.

[0044] Please refer to Figure 5 The passive prestress device 4 has a prestress node groove 402, two jacks 401 are arranged side by side in the prestress node groove 402, the pressure sensor 404 is in the shape of a circular plate and corresponds to the jack 401 one by one, and four sliding bolts 13 described above are arranged on a single pressure sensor 404.

[0045] Please refer to Figure 1 It can be seen that the support rod 6 has the same width as the prestress node groove 402, and maintains the same width in the length direction. In this way, the support rod is actually designed to be thickened, which can enhance the overall strength of the support rod, is convenient for manufacturing, and has better stress stability.

[0046] Please refer to Figure 1 The support beam 7 is supported by the stand column 8.

[0047] Please refer to Figures 8-9 The active prestress device 1 includes a perforated jack 104 sleeved outside the steel strand 5, a first anchor 102, a second anchor 105, a guide member 103, and a clamping piece 101; the second piston rod 104b of the perforated jack 104 faces the second anchor 105, and the tail rod 104a of the perforated jack 104 abuts against the precast pier on the containment beam 2;

[0048] The clamping piece 101 is conical, and in specific operation, the clamping piece 101 is manually inserted into the small hole of the second anchor 105, the second anchor 105 is placed close to the second piston rod 104b, and then the perforated jack 104 is started, so that the clamping piece 101 rapidly locks the second anchor 105 on the left side; with the jacking action of the jack, the top rod 104a applies force to the pier on the enclosure beam, and the first anchor 102 on the right side is also locked by the corresponding clamping piece 101, so that the locking function is realized; wherein the guide member 103 is a split detachable structure, located between the perforated jack 104 and the first anchor 102, and used for preventing the clamping piece 101 on the first anchor 102 from falling off and guiding the steel strand 5.

[0049] The prestress system mainly comprises two sets of hydraulic systems of the through-jack and the transverse jack, and the two sets of systems can be used cooperatively or independently to cope with different working conditions.

[0050] The prestress system is of a double-prestress application mode, one of which is to apply prestress by actively tensioning the steel strand through an active prestress device, and the other of which is to elongate the support rod through a passive prestress device (jack jacking) to passively tension the steel strand and apply prestress, so that the prestress application effect is better.

[0051] The steel strand is used instead of a steel rod as a tension member of the beam string structure, the stress of the steel strand is more balanced, a large-span beam string structure can be realized, the large-span beam string structure can provide a larger working surface for construction, the use of concrete supports in the foundation pit is obviously reduced, and the installation and disassembly are convenient and fast, energy saving and environmental protection are achieved, and the construction period is saved.

[0052] In the design of the steel strand, the angle steel 301 is fixed on the support rod 6, and the first limiting bolt 302 is arranged on the support beam 7, so that the stress function can be realized, and due to single-point stress, the angle of the support rod 6 can be slightly changed, and the adaptability is improved.

[0053] As a preferred scheme, the counterbores are arranged on the fixed plate, the sliding bolt and the pressure sensor can slide horizontally and slightly under the limitation of the counterbores, the self-adaptability can be improved, and the local stress can be reduced.

[0054] The fixed plate, the passive prestress device, the active prestress device and other components are assembled, can be recycled and used, and do not produce construction waste. The structure scheme can be replaced in time according to project changes, the design applicability is strong, and the flexibility is high.

[0055] The above are preferred embodiments of the present application, and those skilled in the art can make various transformations or improvements on the basis of the above, and these transformations or improvements shall all belong to the scope of protection of the present application without departing from the general concept of the present application.

Claims

1. A long-span beam string structure, characterized in that: it comprises active prestressing devices (1), struts (6), steel strands (5), passive prestressing devices (4), and support beams (7); the tail end of the strut (6) is provided with a smooth groove surface (602a) and a second limiting bolt (601), which form a steel strand groove (602); the front end of the strut (6) is connected with the passive prestressing device (4), and the passive prestressing device (4) acts on the enclosure beam (2); the steel strand (5) passes through each steel strand groove (602), and the two ends pass through the embedded sleeve (9) on the enclosure beam (2) and are connected with the active prestressing device (1); one side surface of the strut (6) is fixedly connected with one side surface of an angle steel (301), a limiting slot hole (301a) is formed in the other side surface of the angle steel (301), a first limiting bolt (302) fixedly arranged on the strut (6) is clamped into the limiting slot hole (301a), the first limiting bolt (302) can slightly slide along the limiting slot hole (301a), the strut (6) is slightly adjusted with the enclosure beam, and the first limiting bolt (302) simultaneously plays a role of force bearing and self-adaptive adjustment; it further comprises a fixed plate (10) and a plurality of sliding bolts (13); the passive prestressing device (4) comprises a jack (401), the piston rod (403) of the jack (401) is connected with a pressure sensor (404), the pressure sensor (404) is in the form of a plate, and a plurality of through holes are uniformly arranged on the pressure sensor (404); a plurality of transverse countersunk pull holes are formed in the fixed plate (10), the sliding bolts (13) are inserted into the countersunk pull holes, sequentially pass through the fixed plate (10), the through holes, and are fixedly connected with the threaded segments of the sliding bolts (13) by using first nuts (14); a threaded embedded dowel (11) is embedded on the enclosure beam (2), the embedded dowel (11) passes through the opening pre-set on the fixed plate (10), and is fixedly connected with the threaded segment of the embedded dowel (11) by using a second nut (15); when the passive prestressing device (4) is pressed, the pressure sensor (404) can slightly slide transversely along the countersunk pull hole.

2. The long-span beam string structure of claim 1, wherein: The smooth groove surface (602a) is in the form of an arc surface.

3. The long-span beam string structure of claim 1, wherein: The countersunk pull hole is in the form of a waist-shaped stepped hole, the bolt head of the sliding bolt (13) is sunk into the waist-shaped stepped hole, and the bolt head does not protrude from the fixed plate (10).

4. The long-span beam string structure of claim 1, wherein: The pressure sensor (404) is fixedly connected with the piston rod (403) of the jack (401) by an inner hexagonal bolt (405) at the center.

5. The long-span beam string structure of claim 1, wherein: The passive prestressing device (4) has a prestressed node groove (402), two jacks (401) are arranged side by side in the prestressed node groove (402), the pressure sensor (404) is in the form of a circular plate and corresponds to the jacks (401) one by one, and four sliding bolts (13) are arranged on a single pressure sensor (404).

6. The long-span beam string structure of claim 3, wherein: The strut (6) has the same width as the prestressed node groove (402), and maintains the same width in the length direction.

7. The long-span beam string structure of claim 1, wherein: The support beam (7) is supported by a stand column (8).

8. The long-span beam string structure according to claim 1, characterized in that: The active prestressing device (1) comprises a perforated jack (104) sleeved outside the steel strand (5), a first anchor (102), a second anchor (105), a guide member (103), and a clamping piece (101); The clamping piece (101) is tapered and can be inserted into the small holes of the first anchor (102) and the second anchor (105) to achieve locking; The piston rod (104b) of the perforated jack (104) faces the second anchor (105), and the tail rod (104a) of the perforated jack (104) abuts against the prefabricated pier on the enclosure beam (2); The guide member (103) is a split detachable structure located between the perforated jack (104) and the first anchor (102) and used for preventing the clamping piece (101) on the first anchor (102) from falling off and guiding the steel strand (5).

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