Construction method of double I-beam bracket

Abstract

This invention discloses a construction method for a double-span I-beam girders. The method includes the following steps: S1, construction of retaining piles and capping beams for the foundation pit; S2, excavation of the first layer of soil in the foundation pit; S3, fabrication of the girders, which include a base, adjusting components, and a top support. The base is U-shaped, and adjusting components are installed on its two vertical sections. From bottom to top, the adjusting components include a lower threaded sleeve, an adjusting rod, and an upper threaded sleeve. The top support includes an inner support rod, an outer support rod, and a support rod; S4, leveling the bottom of the first layer of the foundation pit and placing the girders; S5, suspending the lower I-beam onto the support rod and adjusting the elevation of the support rod and the lower I-beam; S6, inserting anchor bolts into anchor cable holes, with the anchor bolts installed at an angle; S7, suspending the upper I-beam onto the anchor bolt; S8, installing anchorages at the outer ends of the anchor bolts. This invention is safe and simple to construct, has a fast construction speed, a short construction period, improves construction efficiency, accelerates construction progress, and significantly reduces construction costs.

Description

Technical Field

[0001] This invention relates to the construction of building foundation pits, and in particular to a construction method for a double-section I-beam girders. Background Technology

[0002] Currently, in deep foundation pit construction, the common support measures are pile-anchor support structures with vertically arranged prestressed anchor rods. Double-layered I-beams are used to transform the anchor rod support for the retaining structure from a single point to a straight line, thereby improving the stability of the retaining structure. Two common construction methods are as follows:

[0003] 1. After the earthwork is excavated, determine the elevation of the steel waist beam along the range of the steel waist beam, arrange the soil piles at appropriate intervals, and use lifting machinery to place the steel beam on the soil piles. Use materials such as stones and steel plates to adjust the angle of the steel beam. This method will cause the soil piles to settle due to the weight of the steel beam, which can easily cause the steel beam to deviate.

[0004] 2. After earthwork excavation, the elevation of the steel waist beam is determined along its range. Concrete brackets are arranged at appropriate intervals, and processes such as drilling and rebar installation, formwork erection, and concrete pouring are carried out. After the concrete reaches strength, the steel waist beam is placed on the concrete brackets using lifting machinery. The steel waist beam bracket supports are mainly welded from angle steel and fixed with anchor bolts. Bolt holes are drilled according to the design positions, with bolts generally not smaller than M25, and the drilling depth not less than the anchor bolt depth. The brackets are installed according to the design positions, ensuring that the top surface alignment is consistent to facilitate the installation of the steel waist beam. After the brackets are installed, the pre-fabricated steel waist beams are directly installed on them. This method involves too many construction steps, has a long construction period, and is difficult to construct. Because brackets need to be installed at each layer of waist beam location and cannot be reused, the manufacturing and construction costs are high.

[0005] The two construction methods described above often fail to achieve the required straight anchor rod penetration due to poor angle and elevation control during on-site construction. This results in the inability to meet the corresponding axial force and locking values ​​during subsequent prestressing tensioning and locking. Therefore, it is crucial to solve the problem of installing the double-span I-beams at the designed elevation and angle, ensuring straight alignment and uniform stress distribution.

[0006] Chinese utility model patent application CN211113671U discloses a double-section steel wainscoting. This utility model moves the pedestal to the outer end of the anchor cable, but does not mention the construction method or the process of adjusting the elevation. Summary of the Invention

[0007] The present invention aims to solve the above-mentioned technical problems, thereby providing a safe, simple, and efficient construction method for I-beam double-section waist beam brackets.

[0008] The technical solution adopted by this invention to solve its technical problem is as follows:

[0009] A construction method for a double-span I-beam girders bracket includes the following steps:

[0010] S1. Construction of retaining piles and capping beams for the foundation pit;

[0011] S2. Excavation of the first layer of soil in the foundation pit, drilling of anchor cable holes in the retaining piles;

[0012] S3, Making the bracket

[0013] The bracket includes a base, an adjustment assembly, and a top support. The base is U-shaped, and the adjustment assembly is installed on the two vertical parts of the base. The adjustment assembly includes, from bottom to top, a lower threaded sleeve, an adjustment rod, and an upper threaded sleeve. The top support includes an inner support rod, an outer support rod, and a support rod. The inner and outer support rods are both T-shaped. The short rods of the inner and outer support rods are arranged vertically, and the long rods of the inner and outer support rods are arranged at an angle. The support rod is L-shaped, and the long rod is arranged at an angle. The long rod is placed on the long rods of the inner and outer support rods and is fixedly connected to the long rods of the inner and outer support rods respectively.

[0014] S4. Level the bottom of the first layer of the foundation pit and place the brackets;

[0015] S5. Hoist the lower I-beam onto the support rod and adjust the elevation of the support rod and the lower I-beam.

[0016] S6. Insert the anchor bolt into the anchor cable hole, and install the anchor bolt at an angle;

[0017] S7. Hoist the upper I-beam onto the anchor bolt;

[0018] S8. Anchorage is installed at the outer end of the anchor bolt.

[0019] Compared with the prior art, the present invention, which adopts the above technical solution, has the following beneficial effects:

[0020] Construction is safe and simple, fast, and quick, solving the problem of cumbersome construction processes in traditional methods, improving construction efficiency, accelerating construction progress, and significantly reducing construction costs. The brackets are simple to manufacture, low in cost, and can be reused.

[0021] Furthermore, the optimized solution of the present invention is:

[0022] The base has L-shaped stabilizing rods symmetrically fixed to both sides of its horizontal section, with the two stabilizing rods forming a cross shape.

[0023] The height of the short rod section of the top support is greater than the height of the flange plate of the lower I-beam.

[0024] The angle between the long and short sections of both the inner and outer support rods is 90 degrees, which is the sum of the anchor rod's inclination angle.

[0025] The sum of the lengths of the long sections of the inner and outer support rods is greater than half the width of the I-beam.

[0026] The spacing between the brackets is 1-1.5 meters.

[0027] At least one bracket shall be placed at each adjacent anchor bolt. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the overall structure of an embodiment of the present invention;

[0029] Figure 2 yes Figure 1 AA section view;

[0030] Figure 3 This is a schematic diagram of the bracket's adjustment components;

[0031] Figure 4 This is a schematic diagram of the top support of the bracket.

[0032] In the diagram: 1. Retaining pile; 2. Anchor bolt; 3. Anchor; 4. Base; 4-1. Stabilizer; 5. Adjustment assembly; 5-1. Lower threaded sleeve; 5-2. Adjustment rod; 5-3. Upper threaded sleeve; 6. Top support; 6-1. Inner support rod; 6-2. Outer support rod; 6-3. Support rod; 7. Lower I-beam; 8. Upper I-beam. Implementation

[0033] The present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0034] See Figure 1 This embodiment describes a construction method for a double-span I-beam girders bracket, which is carried out according to the following steps:

[0035] S1. Construction of retaining piles 1 or retaining wall for the foundation pit, and construction of capping beam (not shown in the figure) on the upper part of retaining piles 1;

[0036] S2. Excavation of the first layer of soil in the foundation pit, drilling anchor cable holes in retaining pile 1;

[0037] S3, Making the bracket

[0038] The bracket mainly consists of a base 4, an adjusting component 5, and a top support 6. The base 4 is U-shaped, with the height of its vertical part near the retaining pile 1 being lower than the height of its vertical part away from the retaining pile 1. The base 4 is made of steel reinforcement. Horizontal stabilizing rods 4-1 are symmetrically welded to both sides of the horizontal part of the base 4. The stabilizing rods 4-1 are L-shaped, and the two stabilizing rods 4-1 form a cross shape. Figure 2 (as shown)

[0039] Adjustment components 5 are installed on the two vertical parts of the base 4. The adjustment components 5 are composed of a lower threaded sleeve 5-1, an adjusting rod 5-2, and an upper threaded sleeve 5-3 from bottom to top. Figure 3 As shown), the upper ends of the two vertical parts of the base 4 are respectively screwed with lower threaded sleeves 5-1, the lower end of the adjusting rod 5-2 is screwed into the lower threaded sleeve 5-1, and the upper threaded sleeve 5-3 is screwed into the upper end of the adjusting rod 5-2.

[0040] The top support 6 is mainly composed of an inner support rod 6-1, an outer support rod 6-2, and a support rod 6-3. Both the inner support rod 6-1 and the outer support rod 6-2 are in a double-shaped configuration. The short rods of the inner support rod 6-1 and the outer support rod 6-2 are arranged vertically, while the long rods of the inner support rod 6-1 and the outer support rod 6-2 are arranged at an angle. The angle between the long rod and the short rod of the inner support rod 6-1 is the sum of 90 degrees and the angle of inclination of the anchor rod 2. The angle of the outer support rod 6-2 is the same as the angle of the inner support rod 6-1. The long rods of the inner support rod 6-1 and the outer support rod 6-2 are parallel to the anchor rod 2.

[0041] The support rod 6-3 is L-shaped, with its long section arranged at an angle. The long section of the support rod 6-3 is placed on the long sections of the inner support rod 6-1 and the outer support rod 6-2. The long section of the support rod 6-3 is welded to the long sections of the inner support rod 6-1 and the outer support rod 6-2 respectively. The weld length is sufficient to meet the requirement of 5d for double-sided welding or 10d for single-sided welding. The long section of the support rod 6-3 is parallel to the anchor rod 2. The height of the short section of the support rod 6-3 is greater than the height of the flange plate of the lower I-beam 7. The length of the long section of the support rod 6-3 is greater than the width of the lower I-beam 7. To meet the overall stability, the horizontal distance between the non-overlapping bent sections of the inner support rod 6-1 and the outer support rod 6-2 must be greater than half the width of the I-beam. That is, the sum of the total lengths of the long sections of the inner support rod 6-1 and the outer support rod 6-2 is greater than half the width of the I-beam. The base 4, the adjusting component 5, and the top support 6 are assembled into an integral bracket.

[0042] S4. The bottom of the first layer of the foundation pit shall be leveled and brackets shall be placed. The spacing between the brackets shall be 1-1.5 meters, and at least one bracket shall be placed at each of the two adjacent anchor bolts.

[0043] S5. Use lifting equipment to hoist the lower I-beam 7 onto the support rod 6-3, and adjust the adjustment component 5 of the bracket to adjust the elevation of the support rod 6-3 and the lower I-beam 7.

[0044] S6. Insert anchor bolt 2 into the anchor cable hole, with anchor bolt 2 installed at an angle;

[0045] S7. Hoist the upper I-beam 8 onto the anchor bolt 2;

[0046] S8, Anchor 3 is installed at the outer end of anchor bolt 2.

[0047] This method ensures that the angle and elevation of the double-layered I-beam girders meet the requirements of on-site use, and that materials are sourced locally and can be reused, significantly reducing construction costs and accelerating construction progress.

[0048] The above description is merely a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. All equivalent structural changes made based on the description and drawings of the present invention are included within the scope of the present invention.

Claims

1. A construction method for a double-span I-beam girders bracket, comprising the following steps: S1. Construction of retaining piles and capping beams for the foundation pit; S2. Excavation of the first layer of soil in the foundation pit, drilling of anchor cable holes in the retaining piles; S3, Making the bracket The bracket includes a base, an adjustment assembly, and a top support. The base is U-shaped, and the adjustment assembly is installed on the two vertical parts of the base. The adjustment assembly includes, from bottom to top, a lower threaded sleeve, an adjustment rod, and an upper threaded sleeve. The top support includes an inner support rod, an outer support rod, and a support rod. The inner and outer support rods are both T-shaped. The short rods of the inner and outer support rods are arranged vertically, and the long rods of the inner and outer support rods are arranged at an angle. The support rod is L-shaped, and the long rod is arranged at an angle. The long rod is placed on the long rods of the inner and outer support rods and is fixedly connected to the long rods of the inner and outer support rods respectively. S4. Level the bottom of the first layer of the foundation pit and place the brackets; S5. Hoist the lower I-beam onto the support rod and adjust the elevation of the support rod and the lower I-beam. S6. Insert the anchor bolt into the anchor cable hole, and install the anchor bolt at an angle; S7. Hoist the upper I-beam onto the anchor bolt; S8. An anchor is installed at the outer end of the anchor bolt; The horizontal part of the base is symmetrically fixed with L-shaped stabilizing rods on both sides, and the two stabilizing rods are in a cross shape; The height of the short rod portion of the top support is greater than the height of the flange plate of the lower I-beam; The angle between the long and short sections of the inner and outer support rods is 90 degrees, which is the sum of the anchor rod inclination angle. The sum of the lengths of the long sections of the inner and outer support rods is greater than half the width of the I-beam.

2. The construction method of the I-beam double-section waist beam bracket according to claim 1, characterized in that: The spacing between the brackets is 1-1.5 meters.

3. The construction method of the I-beam double-section waist beam bracket according to claim 1, characterized in that: At least one bracket should be placed at each adjacent anchor bolt.

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