A prefabricated segmented cap beam P-anchor field installation method

Abstract

This invention discloses a method for on-site installation of prefabricated segmented cap beam P-anchors. A first, second, and third support platform are installed at equal intervals on the ground, and a first column is installed on the first support platform. Second and third columns are installed at both ends of the second support platform; a fourth column is installed on the third support platform. The method includes: Step S1, construction of the foundations for the first and second supports; Step S2, prefabrication of the first and second support bases; Step S3, installation of the first and second supports; Step S4, installation of the first, second, third, and fourth segmented cap beams; Step S5, installation of corrugated pipes within the first, second, and third wet joint sections; and Step S6, installation of the first, second, third, and fourth anchor steel strands. This method simplifies the on-site P-anchor threading process and improves the construction effect of the P-anchor steel strands.

Description

Technical Field

[0001] This invention relates to a method for on-site installation of P-anchors for prefabricated segmented cap beams. Background Technology

[0002] Large-span four-port pier cap beams are generally prefabricated in two sections with a 2cm structural joint in the middle. They are prefabricated in the backyard, tensioned once, and then transported to the site for installation. This process places extremely high demands on transportation and lifting capacity, requires stringent precision from the substructure, and has poor self-correcting capabilities. This process results in the P-anchor steel strands being exposed for extended periods. If on-site installation is not possible in a timely manner, the steel strands are highly susceptible to corrosion, affecting the quality of prestressed construction. The P-anchor steel strands are also inconvenient to transport due to being dragged along the outside of the cap beam, creating a safety hazard. After the segmented cap beams are installed, threading the steel strands within a 2m space is difficult. Even slight deviations in installation precision can easily cause misalignment of the structural joint.

[0003] Therefore, a method for on-site installation of prefabricated segmented cap beams using P-anchors is proposed. Summary of the Invention

[0004] The purpose of this invention is to overcome the existing defects and provide a method for on-site installation of P-anchors for prefabricated segmented cap beams, which simplifies the on-site P-anchor threading process and improves the construction effect of P-anchor steel strands.

[0005] The technical solution to achieve the above objectives is:

[0006] A method for on-site installation of precast segmented cap beams with P-anchors includes installing a first, second, and third bearing platform at equal intervals on the ground, and installing a first column on the first bearing platform; installing the second and third columns at both ends of the second bearing platform; and installing a fourth column on the third bearing platform; comprising:

[0007] Step S1: Construction of the foundation for the first and second supports;

[0008] Step S2: Prefabricate the first support base and the second support base;

[0009] Step S3: Install the first bracket and the second bracket;

[0010] Step S4: Install the first segment cap beam, the second segment cap beam, the third segment cap beam, and the fourth segment cap beam;

[0011] Step S5: Install corrugated pipes in the first wet joint section, the second wet joint section and the third wet joint section;

[0012] Step S6: Install the first anchor steel bundle, the second anchor steel bundle, the third anchor steel bundle, and the fourth anchor steel bundle;

[0013] Step S7: Install P anchors and construct reinforcement for the first wet joint section, the second wet joint section, and the third wet joint section;

[0014] Step S8, install the foam board;

[0015] Step S9: Cast concrete in place for the first wet joint section, the third wet joint section, and the second wet joint section in sequence;

[0016] Step S10: Curing, and tensioning the first anchor steel bundle, the second anchor steel bundle, the third anchor steel bundle, and the fourth anchor steel bundle after meeting the requirements.

[0017] Preferably, step S1 includes,

[0018] Step S11: The first support foundation and the second support foundation are built on the ground inside the first column and the fourth column, respectively. After excavating the original ground to 60cm, construction waste is filled in two layers. Each layer is compacted and the thickness of a single layer is no more than 30cm.

[0019] Step S12 involves random sampling and static load testing to verify that the foundation bearing capacity meets the design requirements, which then serves as the foundation for the first support base and the second support base.

[0020] Preferably, step S2 includes,

[0021] Step S21: The first support base and the second support base are prefabricated using reinforced concrete;

[0022] Step S22: After leveling and placing the support on the foundations of the first and second supports, preload is applied, and the pre-embedded bolts of the base are connected to the steel supports of the first and second supports.

[0023] Preferably, step S3 includes adjusting the elevation of the top of the first support and the second support using a sandbox, and padding the contact surface between the sandbox and the bottom of the first segmented cap beam and the fourth segmented cap beam with geotextile to prevent rust contamination.

[0024] Preferably, step S4 includes using a crawler crane to sequentially lift the first segmented cap beam onto the first column and the first support, the second segmented cap beam onto the second column, the third segmented cap beam onto the third column, and the fourth segmented cap beam onto the fourth column and the second support; wherein the center of gravity of the second segmented cap beam and the third segmented cap beam overlaps with the center of the second column and the third column, respectively.

[0025] Preferably, step S6 includes,

[0026] Step S61: The first anchor steel bundle is installed above the second anchor steel bundle, and the first anchor steel bundle and the second anchor steel bundle pass sequentially from the left side of the first segmented cap beam through the first segmented cap beam, the first wet joint section and the second segmented cap beam to the left side of the vertical centerline of the second wet joint section;

[0027] In step S62, the third anchor steel bundle is installed above the fourth anchor steel bundle, and the third anchor steel bundle and the fourth anchor steel bundle pass sequentially from the right side of the fourth segment cap beam, through the fourth segment cap beam, the third wet joint section, and the third segment cap beam to the right side of the vertical centerline of the second wet joint section.

[0028] Preferably, step S8 includes installing a 2cm thick foam board at the vertical centerline position of the second wet joint section and clamping the foam board with a steel mesh.

[0029] Preferably, step S9 includes sequentially pouring concrete into the first wet joint section, the third wet joint section, and the second wet joint section.

[0030] The beneficial effects of this invention are:

[0031] This invention solves the problem of corrosion caused by prolonged exposure of the first, second, third, and fourth anchor steel strands by inserting the first, second, third, and fourth anchor steel strands during the pouring of the first, second, and third wet joint sections; it also solves the problem of inconvenient transportation of the first, second, third, and fourth anchor steel strands.

[0032] By using the first and second anchor steel strands to pass sequentially from the left side of the first segment cap beam, through the first wet joint section and the second segment cap beam to the left side of the vertical centerline of the second wet joint section, and by using the third and fourth anchor steel strands to pass sequentially from the right side of the fourth segment cap beam, through the fourth segment cap beam, the third wet joint section and the third segment cap beam to the right side of the vertical centerline of the second wet joint section, the problem of inconvenient installation of P anchors at the 2m first, second and third wet joint sections is solved. Attached Figure Description

[0033] Figure 1 This is a flowchart of a prefabricated segmented cap beam P-anchor on-site installation method according to the present invention;

[0034] Figure 2 This is a structural diagram of the prefabricated segmented cap beam P-anchor of the present invention;

[0035] Figure 3 yes Figure 2 Sectional view from direction 1-1;

[0036] Figure 4 This is a diagram showing the installation of the first support foundation and the second support foundation according to the present invention;

[0037] Figure 5 This is a diagram showing the first bracket base, the second bracket base, the first bracket, and the second bracket after installation according to the present invention;

[0038] Figure 6 This is a diagram showing the installation of the first, second, third, and fourth section cap beams of the present invention.

[0039] Figure 7 This is a diagram showing the installation of the first, second, third, and fourth anchor steel bundles according to the present invention.

[0040] Figure 8 This is a diagram showing the installation of corrugated pipes in the first wet joint section, the second wet joint section, and the third wet joint section of the present invention.

[0041] Figure 9 This is a diagram showing the installation of the P-anchor according to the present invention;

[0042] Figure 10 This is a diagram of the first wet joint section, the third wet joint section, and the second wet joint section after the concrete has been poured.

[0043] In the diagram: 1. First segment cap beam; 2. Second segment cap beam; 3. Third segment cap beam; 4. Fourth segment cap beam; 5. First column; 6. Second column; 7. Third column; 8. Fourth column; 9. First foundation; 10. Second foundation; 11. Third foundation; 12. First support; 13. First support base; 14. First support foundation; 15. Second support; 16. Second support base; 17. Second support foundation; 18. First wet joint section; 19. Second wet joint section; 20. Third wet joint section; 21. P-anchor; 22. First anchor steel strand; 23. Second anchor steel strand; 24. Third anchor steel strand; 25. Fourth anchor steel strand. Detailed Implementation

[0044] The technical solution of the present invention will now be clearly and completely described in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0045] The invention will now be further described with reference to the accompanying drawings.

[0046] like Figure 1-10 This illustrates a method for on-site installation of a precast segmented cap beam P-anchor, comprising: installing a first bearing platform 9, a second bearing platform 10, and a third bearing platform 11 at equal intervals on the ground; installing a first column 5 on the first bearing platform 9; installing a second column 6 and a third column 7 at both ends of the second bearing platform 10; and installing a fourth column 8 on the third bearing platform 11; including:

[0047] Step S1, foundation construction of the first support foundation 14 and the second support foundation 17; including,

[0048] Step S11: The first support foundation 14 and the second support foundation 17 are built on the ground inside the first column 5 and the fourth column 8, respectively. After excavating the original ground to 60cm, construction waste is filled in two layers. Each layer is compacted and the thickness of a single layer is no more than 30cm.

[0049] Step S12, and random inspections are conducted to verify the static load test. Once the foundation bearing capacity meets the design requirements, it serves as the foundation for the first support base 13 and the second support base 16.

[0050] Step S2, prefabricate the first support base 13 and the second support base 16; including,

[0051] Step S21: The first support base 13 and the second support base 16 are prefabricated using C40 reinforced concrete.

[0052] Step S22: After leveling and placing the base on the first support foundation 14 and the second support foundation 17, preload is applied. The pre-embedded bolts of the base are connected to the steel supports of the first support 12 and the second support 15.

[0053] Step S3: Install the first support 12 and the second support 15; the top of the first support 12 and the second support 15 are adjusted with sand boxes, and geotextile is placed on the contact surface between the sand box and the bottom of the first segment cap beam 1 and the fourth segment cap beam 4 to prevent rust contamination.

[0054] Step S4: Install the first segment cap beam 1, the second segment cap beam 2, the third segment cap beam 3, and the fourth segment cap beam 4. A crawler crane sequentially lifts the first segment cap beam 1 onto the first column 5 and the first support 12, the second segment cap beam 2 onto the second column 6, the third segment cap beam 3 onto the third column 7, and the fourth segment cap beam 4 onto the fourth column 8 and the second support 15. The centers of gravity of the second segment cap beam 2 and the third segment cap beam 3 overlap with the centers of the second column 6 and the third column 7, respectively. After the first segment cap beam 1 and the fourth segment cap beam 4 are positioned eccentrically, temporary first supports 12 and second supports 15 need to be erected on the other side of the center of gravity using steel profiles. These supports, together with the first column 5 and the fourth column 8, bear the load of a single segment cap beam to achieve balance and stability.

[0055] Step S5: Install corrugated pipes in the first wet joint section 18, the second wet joint section 19 and the third wet joint section 20.

[0056] Step S6, install the first anchor strand 22, the second anchor strand 23, the third anchor strand 24, and the fourth anchor strand 25; including,

[0057] In step S61, the first anchor steel bundle 22 is installed above the second anchor steel bundle 23, and the first anchor steel bundle 22 and the second anchor steel bundle 23 pass through the first segment cap beam 1, the first wet joint section 18 and the second segment cap beam 2 from the left side of the first segment cap beam 1 to the left side of the vertical centerline of the second wet joint section 19.

[0058] In step S62, the third anchor steel bundle 24 is installed above the fourth anchor steel bundle 25, and the third anchor steel bundle 24 and the fourth anchor steel bundle 25 pass through the fourth segment cap beam 4, the third wet joint section 20 and the third segment cap beam 3 from the right side of the fourth segment cap beam 4 to the right side of the vertical centerline of the second wet joint section 19.

[0059] Step S7: Install the P-anchor 21 anchorage for binding the first anchor steel bundle 22, the second anchor steel bundle 23, the third anchor steel bundle 24 and the fourth anchor steel bundle 25, and carry out the reinforcement construction of the first wet joint section 18, the second wet joint section 19 and the third wet joint section 20.

[0060] Step S8, install foam board; install a 2cm thick foam board at the vertical centerline of the second wet joint section 19, and clamp the foam board with steel mesh.

[0061] In step S9, concrete is poured in place for the first wet joint section 18, the third wet joint section 20, and the second wet joint section 19 in sequence; C60 concrete is poured in place for the first wet joint section 18, the third wet joint section 20, and the second wet joint section 19 in sequence. At this time, the first segment cap beam 1 and the second segment cap beam 2 are connected as a whole, and the third segment cap beam 3 and the fourth segment cap beam 4 are connected as a whole.

[0062] Step S10 involves curing and tensioning the first anchor steel strand 22, the second anchor steel strand 23, the third anchor steel strand 24, and the fourth anchor steel strand 25 after meeting the requirements. Once tensioned, these strands provide upward bending stress within the beam, ensuring that the first segment cap beam 1 and the fourth segment cap beam 4 can withstand their own weight without cracking after the removal of the first support 12 and the second support 15.

[0063] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for on-site installation of a precast segmented cap beam P-anchor, wherein a first bearing platform (9), a second bearing platform (10), and a third bearing platform (11) are installed at equal intervals on the ground, and a first column (5) is installed on the first bearing platform (9); a second column (6) and a third column (7) are installed at both ends of the second bearing platform (10); and a fourth column (8) is installed on the third bearing platform (11); characterized in that, include: Step S1: Construction of the foundation of the first support (14) and the second support (17); Step S2: Prefabricate the first support base (13) and the second support base (16). Step S3: Install the first bracket (12) and the second bracket (15); Step S4: Install the first segment cap beam (1), the second segment cap beam (2), the third segment cap beam (3), and the fourth segment cap beam (4). Step S5: Install corrugated pipes in the first wet joint section (18), the second wet joint section (19), and the third wet joint section (20); Step S6: Install the first anchor steel bundle (22), the second anchor steel bundle (23), the third anchor steel bundle (24), and the fourth anchor steel bundle (25). Step S7, install P anchor (21) and construct reinforcement for the first wet joint section (18), the second wet joint section (19) and the third wet joint section (20); Step S8, install the foam board; Step S9: Cast concrete in place for the first wet joint section (18), the third wet joint section (20) and the second wet joint section (19) in sequence; Step S10: Curing and tensioning the first anchor steel bundle (22), the second anchor steel bundle (23), the third anchor steel bundle (24), and the fourth anchor steel bundle (25) after meeting the requirements. Step S6 includes, Step S61, the first anchor steel bundle (22) is installed above the second anchor steel bundle (23), and the first anchor steel bundle (22) and the second anchor steel bundle (23) pass sequentially from the left side of the first segmented cap beam (1), through the first segmented cap beam (1), the first wet joint section (18) and the second segmented cap beam (2) to the left side of the vertical centerline of the second wet joint section (19); In step S62, the third anchor steel bundle (24) is installed above the fourth anchor steel bundle (25), and the third anchor steel bundle (24) and the fourth anchor steel bundle (25) pass sequentially from the right side of the fourth segment cap beam (4), the third wet joint section (20) and the third segment cap beam (3) to the right side of the vertical centerline of the second wet joint section (19).

2. The on-site installation method for a precast segmented cap beam P-anchor according to claim 1, characterized in that, Step S1 includes, Step S11: The first support foundation (14) and the second support foundation (17) are built on the ground inside the first column (5) and the fourth column (8), respectively. The original ground is excavated to 60cm and then filled with construction waste in two layers. Each layer is compacted and the thickness of a single layer is no more than 30cm. Step S12: A static load test is conducted on a random sample to verify that the bearing capacity of the foundation meets the design requirements. This foundation is then used as the base for the first support base (13) and the second support base (16).

3. The on-site installation method for a precast segmented cap beam P-anchor according to claim 1, characterized in that, Step S2 includes, Step S21: The first support base (13) and the second support base (16) are prefabricated with reinforced concrete. Step S22: After leveling and placing the base on the first support foundation (14) and the second support foundation (17), preload is applied. The base is pre-embedded with bolts and connected to the steel supports of the first support (12) and the second support (15).

4. The on-site installation method for a precast segmented cap beam P-anchor according to claim 1, characterized in that, Step S3 includes adjusting the elevation of the top of the first support (12) and the second support (15) using sandboxes, and padding the sandboxes with geotextiles on the contact surfaces of the bottom of the first segmented cap beam (1) and the fourth segmented cap beam (4).

5. The on-site installation method for a precast segmented cap beam P-anchor according to claim 1, characterized in that, Step S4 includes the following steps: a crawler crane sequentially lifts the first segmented cap beam (1) onto the first column (5) and the first support (12), the second segmented cap beam (2) onto the second column (6), the third segmented cap beam (3) onto the third column (7), and the fourth segmented cap beam (4) onto the fourth column (8) and the second support (15); wherein the center of gravity of the second segmented cap beam (2) and the third segmented cap beam (3) overlaps with the center of the second column (6) and the third column (7), respectively.

6. The on-site installation method for a precast segmented cap beam P-anchor according to claim 1, characterized in that, Step S8 includes installing a 2cm thick foam board at the vertical centerline position of the second wet joint section (19) and clamping the foam board with a steel mesh.

7. The on-site installation method for a precast segmented cap beam P-anchor according to claim 1, characterized in that, Step S9 includes pouring concrete into the first wet joint section (18), the third wet joint section (20), and the second wet joint section (19) in sequence.

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