Existing pipeline protection device for large-span foundation pit excavation

Abstract

The utility model discloses an existing pipeline protection device for large-span foundation pit excavation, a pipeline is arranged across a foundation pit, and the protection device comprises a supporting mechanism and a hanging mechanism. The supporting mechanism comprises two rows of foundation pit supporting structures, continuous cover beams are arranged at the tops of the foundation pit supporting structures, door-shaped buttresses are arranged on the cover beams, and fixed pulleys for supporting steel wire ropes are arranged at the tops of the buttresses; the suspension mechanism is arranged along the trend of the existing pipeline and comprises two steel wire ropes arranged in parallel, one end of each steel wire rope is fixedly connected in a ground anchor, the other end of each steel wire rope is pulled and suspended through a balancing weight, multiple groups of upper cross beams arranged at equal intervals are arranged between the two steel wire ropes, and two ends of each upper cross beam are suspended and connected with lower cross beams below the pipeline through suspenders. The existing pipeline is protected by the tension provided by the steel cable, the deformation of the steel wire rope caused by thermal expansion and cold contraction is eliminated by the counter weight traction and the fixed pulley combined structure, the pipeline damage caused by the deformation of the suspender is prevented, the middle support of the foundation pit is reduced, a larger construction working surface is provided, the construction is accelerated, and the investment is saved.

Description

Technical Field

[0001] The utility model belongs to the technical field of municipal engineering, and specifically relates to the design of an existing pipeline protection device for large-span foundation pit excavation. Background Art

[0002] With the acceleration of urban construction, road reconstruction, subway construction, rainwater and sewage diversion, power pipelines, gas pipelines and other reconstruction and new construction all face the excavation of deep foundation pits. When excavating the foundation pits, the protection of existing pipelines faces many problems. Some of them are damaged due to excessive deformation of the supporting structure. Some of them are not suitable for foundation pits with larger spans and cannot provide effective protection devices. Some of them also limit the types of pipelines and cannot use pipelines that are too heavy. Summary of the invention

[0003] The utility model discloses a protection device for existing pipelines in large-span foundation pit excavation according to the shortcomings of the prior art. The utility model aims to provide a novel protection device for existing pipelines in large-span foundation pit excavation, which is used to solve the problem that the supporting structure is too deformed, is not suitable for large-span foundation pit excavation and has limited types of existing pipeline protection.

[0004] The utility model is realized by the following technical solutions:

[0005] A protection device for existing pipelines in large-span foundation pit excavation, wherein the existing pipelines are arranged across the foundation pit, and the protection device comprises a supporting mechanism and a hanging mechanism;

[0006] The supporting mechanism is arranged at the two ends of the foundation pit and the foundation pit wall through which the existing pipeline passes, including two rows of foundation pit support structures cast and consolidated and deeply buried along the foundation pit walls at the two ends, and continuous cap beams are cast and consolidated at the top of the two rows of foundation pit support structures, level with the ground, and gate-shaped piers are respectively arranged on the two cap beams and vertically above the existing pipeline; fixed pulleys for supporting steel wire ropes are respectively arranged on both sides of the top of each gate-shaped pier;

[0007] The suspension mechanism is arranged along the existing pipeline, including: two parallel steel ropes, each steel rope is supported in a fixed pulley on the top of the gate-shaped pier, one end of which is fixed by a ground anchor pull ring fixed in the ground anchor, and the other end is suspended by a counterweight block for pulling and fixing; a plurality of groups of upper beams arranged at equal intervals are fixed between the two parallel steel ropes above the foundation pit, and both ends of each upper beam are suspended and connected to a lower beam located below the existing pipeline through a suspension rod, and the lower beam supports the existing pipeline by adjusting the extension and contraction of the suspension rod.

[0008] Furthermore, the foundation pit support structure is an anti-sliding pile, a retaining wall, a retaining pile that is consolidated by pouring along the foundation pit wall; or a steel truss deeply buried pile or column.

[0009] Furthermore, the anchor pull ring at one end of each steel wire rope is fixed by pouring concrete consolidation in a deep pit on the ground, and the other end adopts an integrated structure counterweight block to pull and suspend the two steel wire ropes at the same time. The integrated structure counterweight blocks are stacked in multiple layers according to weight.

[0010] Furthermore, the upper crossbeam and the lower crossbeam are channel steel or I-beam crossbeams; the suspension rod is a screw rod, and the suspension rod is adjustably connected to the upper crossbeam and the lower crossbeam through a nut.

[0011] Furthermore, two U-shaped bolts are arranged on the bottom surface of the upper cross beam, and two parallel steel wire ropes pass through the U-shaped bolts to support and limit the upper cross beam.

[0012] The utility model can adapt to the protection of existing pipelines during the construction of large-span foundation pits through the pulling force provided by the steel cable. The counterweight pulling and fixed pulley combined structure eliminates the deformation of the steel wire rope due to thermal expansion and contraction, prevents the damage of the pipeline caused by excessive deformation of the hanger rod, reduces the support in the middle of the foundation pit, provides a larger construction working surface, is conducive to speeding up construction, and saves project investment. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a schematic elevation diagram of the protective device of the utility model;

[0014] Figure 2 It is a schematic diagram of the foundation pit support structure and pipeline plan of the utility model;

[0015] Figure 3 This is a schematic elevation diagram of a gate-shaped buttress of the utility model protection device;

[0016] Figure 4 It is a top view schematic diagram of the hanging structure of the protection device of the utility model;

[0017] Figure 5 It is a front view schematic diagram of the hanging structure of the protection device of the utility model;

[0018] Figure 6 It is a side view schematic diagram of the hanging structure of the protection device of the utility model;

[0019] Figure 7 This is a schematic diagram of the connection between the upper crossbeam and the steel cable of the protective device of the utility model;

[0020] Figure 8 This is a schematic diagram of the structure of the counterweight block of the protective device of the utility model;

[0021] Fig. 9 It is a schematic diagram of the structure of the anchor pull ring of the protection device of the utility model.

[0022] Description of reference numerals:

[0023] 1—foundation pit, 2—foundation pit support structure, 3—pipeline, 4—cap beam, 5—ground anchor, 6—ground anchor pull ring, 7—pier, 8—wire rope, 9—suspender rod, 10—fixed pulley, 11—counterweight, 12—upper beam, 13—lower beam; 101—embedded bolts, 801—U-bolts. DETAILED DESCRIPTION

[0024] The present invention is further described below in conjunction with specific implementation methods. The specific implementation methods are further descriptions of the principles of the present invention and do not limit the present invention in any way. Technologies identical or similar to the present invention do not exceed the scope of protection of the present invention.

[0025] Combined with the attached pictures.

[0026] As shown in the figure, the utility model discloses a device for protecting existing pipelines for large-span foundation pit excavation, comprising a supporting mechanism and a hanging mechanism.

[0027] The supporting mechanism is arranged at the two ends of the foundation pit and the foundation pit wall through which the existing pipeline passes, including two rows of foundation pit support structures cast and consolidated and deeply buried along the foundation pit walls at the two ends, and continuous cap beams are cast and consolidated at the top of the two rows of foundation pit support structures, level with the ground, and gate-shaped piers are respectively arranged on the two cap beams and vertically above the existing pipeline; fixed pulleys for supporting steel wire ropes are respectively arranged on both sides of the top of each gate-shaped pier;

[0028] The suspension mechanism is arranged along the existing pipeline, including: two parallel steel ropes, each steel rope is supported in a fixed pulley on the top of the gate-shaped pier, one end of which is fixed by a ground anchor pull ring fixed in the ground anchor, and the other end is suspended by a counterweight block for pulling and fixing; a plurality of groups of upper beams arranged at equal intervals are fixed between the two parallel steel ropes above the foundation pit, and both ends of each upper beam are suspended and connected to a lower beam located below the existing pipeline through a suspension rod, and the lower beam supports the existing pipeline by adjusting the extension and contraction of the suspension rod.

[0029] Foundation pit support structure: It can be a support structure such as anti-slide piles, retaining walls, and retaining piles, which are used to protect the stability of the foundation pit side walls and provide support for the fixed pulley. This example uses a retaining pile structure.

[0030] Suspension mechanism: gate-shaped piers standing on the cap beam, fixed pulleys set on the top and both sides of the piers, suspension rods, upper beams, lower beams, and steel ropes;

[0031] One end of the steel wire rope of the suspension mechanism is fixed by an anchoring structure, which is a concrete anchor and anchor pull ring cast and fixed in the ground soil;

[0032] The other end of the steel wire rope of the suspension mechanism adopts a counterweight pulling structure, which enables the steel wire rope to bear the gravity of the pipeline. The counterweight pulling structure adopts a counterweight block that acts on two steel wire ropes at the same time and is stacked in multiple layers. 1 to 2 layers of lead wire mesh can be set inside the counterweight block to increase its crack resistance. The counterweight block is made of concrete and has a groove reserved for inserting the steel cable.

[0033] The utility model is suitable for large-span foundation pits such as pipelines, subways, roads, etc. The utility model is described in detail with a specific embodiment below.

[0034] In this example, the retaining piles are bored cast-in-place piles, and the cap beam 4 is a reinforced concrete structure. In this example, the gate-shaped pier 7 is a reinforced concrete structure with a height of 1.5m. The upper and lower beams are made of channel steel, and the wire rope 8 is made of three steel strands with a diameter of 15.2mm. The upper beam 12 is fixedly connected to the wire rope 8 with U-bolts 801. The suspension rod 9 uses an M14 pull rod with full-length thread, which can be used to adjust the height of the lower beam 13. The fixed pulley 10 is fixed to the pier 7 by embedded bolts 101.

[0035] As shown in the figure, when the cap beam 4 is constructed, the steel bars of the pier 7 should be pre-buried in the cap beam 4. The pulley bolts 101 are pre-buried on the pier 7 in advance.

[0036] By adjusting the effective length of the suspension rod 9, the lower cross beam 13 can fully bear the gravity of the pipeline 3, so that the suspension structure can be fully stressed.

[0037] The steel wire rope 8 passes around the anchor pull ring 6 and is fastened by matching U-shaped bolts 801 , and the number of U-shaped bolts 801 is not less than 3.

[0038] The construction process of the utility model climbing formwork hanging seat system is as follows:

[0039] 1. First, according to the pipeline completion drawing, locate the existing pipeline 3 and determine the type, diameter and burial depth of the pipeline 3. In this embodiment, the pipeline 3 is a water supply steel pipe with a diameter of 300 mm.

[0040] 2. If Figures 1-2 As shown, the installation design requires the construction of retaining piles around the foundation pit 1 and the construction of a cap beam 4 on top of the piles.

[0041] 3. If Figures 1 to 3 As shown, at the top of the cap beam 4 and the center of the pipeline 3, a gate-shaped pier 7 is constructed, and a set pulley 10 and embedded bolts 101 are buried at the top and side of the pier 7.

[0042] 4. If Figure 1 , 8As shown in FIG. 9 , an anchor pit is excavated by an excavator at a certain distance from the foundation pit 1 on one side of the foundation pit 1, and the anchor pull ring 6 is installed and the anchor concrete is poured. On the open space, a sufficient number of counterweight blocks 11 are prefabricated on site using concrete.

[0043] 5. If Figures 1-2 As shown, the foundation pit 1 is excavated. When approaching the bottom of the pipeline 3, excavation is performed from both sides of the pipeline 3 to keep the supporting soil at the bottom of the pipeline 3 from deforming.

[0044] 6. If Figures 1 to 3 As shown, to install the hanging mechanism, first fix one end of the wire rope 8 on the anchor pull ring 6, unfold the wire rope 8, pass it through the fixed pulley 10, to the other side of the foundation pit 1, and install the U-bolt 801 at the end of the wire rope 8, add the counterweight 11, until the wire rope 8 is completely straightened.

[0045] 7. If Figures 4 to 8 As shown, first, the upper cross beam 12 is connected to the wire rope 8 with a U-shaped bolt 801 at a spacing of 1m, and the suspension rod 9 and bolts are installed from top to bottom. Corresponding to the position of the suspension rod 9, the lower cross beam 13 is passed through the bottom of the pipeline 3, connected to the lower part of the suspension rod 9 and the fixing bolts are tightened.

[0046] 8. If Figure 1 As shown, the effective height of the suspension rod 9 is adjusted by the upper bolts so that the pipeline 3 is evenly stressed on the lower cross beam 13 .

[0047] 9. If Figure 1 As shown, the soil layer at the bottom of the pipeline 3 is gradually excavated from both sides to the middle, so that the pipeline 3 is gradually suspended in the air until it is completely.

[0048] 10. At this point, the existing pipeline protection of the large-span foundation pit excavation is completed, and the foundation pit is continued to be excavated until the design requirements are met. When the foundation pit is backfilled, after the bottom of the pipeline is backfilled, the pipeline acts on the bottom soil layer again, and the protective device can be removed. The removal is carried out in the reverse order of installation.

Claims

1. A protection device for existing pipelines in large-span foundation pit excavation, wherein the existing pipelines are arranged across the foundation pit, and the device is characterized by: The protection device includes a supporting mechanism and a hanging mechanism; The supporting mechanism is arranged at the two ends of the foundation pit and the foundation pit wall through which the existing pipeline passes, including two rows of foundation pit support structures cast and consolidated and deeply buried along the foundation pit walls at the two ends, and continuous cap beams are cast and consolidated at the top of the two rows of foundation pit support structures, level with the ground, and gate-shaped piers are respectively arranged on the two cap beams and vertically above the existing pipeline; Fixed pulleys for supporting the steel wire rope are respectively arranged on both sides of the top of each gate-shaped pier; The suspension mechanism is arranged along the existing pipeline, including: two parallel steel ropes, each steel rope is supported in a fixed pulley on the top of the gate-shaped pier, one end of which is fixed by a ground anchor pull ring fixed in the ground anchor, and the other end is suspended by a counterweight block for pulling and fixing; a plurality of groups of upper beams arranged at equal intervals are fixed between the two parallel steel ropes above the foundation pit, and both ends of each upper beam are suspended and connected to a lower beam located below the existing pipeline through a suspension rod, and the lower beam supports the existing pipeline by adjusting the extension and contraction of the suspension rod.

2. The existing pipeline protection device for large-span foundation pit excavation according to claim 1 is characterized by: The foundation pit support structure is anti-sliding piles, retaining walls, and retaining piles that are consolidated by pouring along the foundation pit wall; or Steel trusses are deeply embedded in piles or columns.

3. The existing pipeline protection device for large-span foundation pit excavation according to claim 1 is characterized by: The anchor pull ring at one end of each steel wire rope is fixed by pouring concrete consolidation in a deep pit on the ground, and the other end adopts an integrated structure counterweight block to pull and suspend the two steel wire ropes at the same time. The integrated structure counterweight blocks are stacked in multiple layers according to weight.

4. The existing pipeline protection device for large-span foundation pit excavation according to claim 1 is characterized by: The upper crossbeam and the lower crossbeam are channel steel or I-beam crossbeams; the suspension rod is a screw rod, and the suspension rod is adjustable to connect the upper crossbeam and the lower crossbeam through a nut.

5. The existing pipeline protection device for large-span foundation pit excavation according to claim 1 is characterized by: Two U-shaped bolts are arranged on the bottom surface of the upper cross beam, and two parallel steel wire ropes pass through the U-shaped bolts to support the limiting upper cross beam.

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