A trestle structure vertical load calculation method, device and storage medium

Abstract

The application discloses a kind of trestle structure vertical column pile vertical load calculation method, equipment and storage medium, the method is first by trestle bidirectional plate according to absolute maximum bending moment equivalence is simplified into equivalent uniform load;Second, according to the equivalent uniform load obtained, the vertical load on the trestle bidirectional plate is distributed, to obtain the maximum linear load q corresponding to each beam section;Then, according to the linear load q, the vertical load on the beam is calculated;Finally, the vertical load on the beam is distributed to the vertical column pile.By this calculation method, the size of the vertical load on the vertical column pile can be obtained to verify whether the strength of the vertical column pile meets the requirements, which has certain significance in safety.At the same time, it provides a reference for whether the vertical column pile needs to be reinforced under the condition of subsequent live load change.

Description

Technical Field

[0001] This invention belongs to the field of underground engineering, specifically relating to a method, equipment, and storage medium for calculating the vertical load of the column piles of a trestle structure. Background Technology

[0002] Currently, most buildings in cities have multi-story basements and cover as much of the land boundary as possible, leading to problems such as large excavation areas and cramped construction sites in foundation pit projects. To solve these problems, the construction access roads, material storage areas, and work platforms required for construction are integrated into the support system of the retaining structure, and a construction trestle is set up on the upper part of the support within the foundation pit.

[0003] At present, there is little research on the calculation method of vertical load of the column piles of trestle bridge structure by domestic and foreign scholars. More research is on the calculation method of the load borne by the trestle bridge slab itself. Zheng Jinqiu (Zheng Jinqiu. Design of foundation pit support system for construction trestle bridge [J]. Fujian Construction Science and Technology, 2015, (03): 3-5.) Considering that the construction trestle bridge is a temporary structure, it is proposed that its load value can be converted with reference to the fire truck load value in the "Code for Design of Building Structures". The calculation method is to multiply the normal construction load value by the corresponding safety factor. Xiao Yanjie et al. (Xiao Yanjie, Han Jiangang. Research on equivalent load values ​​of earthmoving vehicles on the deck of foundation pit trestle bridge [J]. Structural Engineer, 2017, 33(05): 179-184.) used ABAQUS finite element software to analyze the construction trestle bridge structure and proposed the equivalent uniformly distributed load formula for one-way and two-way slabs under the action of earthmoving vehicles; Liang Haoqing et al. (Liang Haoqing, You Xuechun, Zhu Hongchang. Research on calculation and analysis method of reinforcement of lattice column of foundation pit trestle bridge [C] / / China Civil Engineering Society Chief Engineer Working Committee. Proceedings of the 2021 Annual Academic Conference and the First Chief Engineer Forum of the China Civil Engineering Society Chief Engineer Working Committee. Shanghai Construction Group Co., Ltd.; Shanghai Construction No. 7 Group Co., Ltd.; 2021: 5. Taking a deep foundation pit project in Shanghai as an example, this paper proposes reinforcement principles and calculation methods for different trestle columns, i.e., pile tilting situations. Based on actual measurement results, the rationality of the proposed reinforcement principles and calculation methods is verified. Jia Hongxue (Jia Hongxue, Yu Changjiang, Tao Changqing, et al. Research on equivalent uniformly distributed load value of concrete mixer truck on foundation pit trestle slab and reinforcement technology [J]. Construction, 2023, 45(10):2138-2141.) took a deep foundation pit in Guangzhou as the background. After comprehensively considering factors such as the span, thickness and vehicle parking position of the trestle slab, the equivalent uniformly distributed load value of the trestle slab surface of this project was calculated based on the maximum absolute bending moment of the trestle slab surface. Effective solutions were proposed to address the problem of insufficient bearing capacity. However, current research mainly focuses on the calculation method of the load borne by the trestle slab itself, and there is no research on the calculation method of the vertical load of the trestle structure pile. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention proposes a method, equipment, and storage medium for calculating the vertical load of the piles in a trestle structure.

[0005] The calculation method for the vertical load of the piles supporting the trestle structure includes the following steps:

[0006] Step 1: The two-way slab of the trestle bridge is simplified to an equivalent uniformly distributed load q based on the absolute maximum bending moment. e ;

[0007] Step 2: Based on the obtained equivalent uniformly distributed load q e The vertical loads on the two-way slabs of the trestle bridge are distributed to obtain the maximum line load q on each beam section.

[0008] Step 3: Calculate the vertical load on the beam based on the line load q;

[0009] Step 4: Distribute the vertical load on the beam to the column piles.

[0010] Furthermore, in step 1, the equivalent uniformly distributed load q e Specifically:

[0011]

[0012] In the formula: l is the length of the short side beam of the two-way slab of the trestle bridge. However, when the two-way slab of the trestle bridge is square, any direction can be selected as the short side beam, and the direction perpendicular to it can be selected as the long side beam; M max The absolute value of the maximum bending moment in the lower span under unfavorable arrangement; k is the bending moment coefficient M in the two-way slab bending moment coefficient table. y0 With M x0 The ratio of β to υ; β is the bending moment calculation coefficient; υ is the Poisson's ratio of concrete.

[0013] Furthermore, the formula for calculating β is as follows:

[0014]

[0015] In the formula, q0 represents the uniformly distributed unit load applied to the two-way slab of the trestle bridge; M x0 M represents the mid-span bending moment in the X direction when υ = 0. x =(1+kυ)M x0 Through M x =M x0 +υM y0 ,

[0016] M y =M y0 +υM x0 M was obtained. x and M y M represents the mid-span bending moment in the X and Y directions. y0This represents the mid-span bending moment in the Y direction when υ = 0.

[0017] Furthermore, in step 2, the calculation method for the line load q is as follows:

[0018]

[0019] In the formula: α is the ratio of half the length of the short side beam of the two-way slab of the trestle bridge to the length of the long side beam of the two-way slab of the trestle bridge; l0 is the length of the long side beam of the two-way slab of the trestle bridge; q is the height of the vertical load within the area of ​​the trapezoid or triangle.

[0020] The allocation is to divide each two-way slab of the trestle bridge into four sections at 45° using the plastic stranding method, and the vertical load on each beam is the sum of the vertical loads within the areas of adjacent trapezoids or triangles.

[0021] Furthermore, in step 3, the vertical load on the beam is divided into vertical load Q1 on the long side beam:

[0022] Q1=q1l0=(1-2α 2 +α 3 )ql0

[0023] The short beam is subjected to a vertical load Q2:

[0024]

[0025] In the formula: q1 is the uniformly distributed load on the long side beam, and q2 is the uniformly distributed load on the short side beam.

[0026] Furthermore, the calculation methods for q1 and q2 are as follows:

[0027] The vertical loads within the trapezoidal area of ​​the long-side beam and the vertical loads within the triangular area of ​​the short-side beam are simplified to uniformly distributed loads based on the principle of equal support bending moments:

[0028] q1=(1-2α 2 +α 3 )q

[0029]

[0030] Furthermore, in step 4, the load distributed to the column piles varies depending on the location of the beam, and can be categorized into three cases:

[0031] 1) Column pile N1 that supports two intersecting beams;

[0032] 2) The column piles N2 and N3 that support three intersecting beams, specifically N2 where two long side beams intersect with one short side beam, and N3 where one long side beam intersects with two short side beams;

[0033] 3) Column pile N4 that supports four intersecting beams.

[0034] Furthermore, the calculation methods for N1, N2, N3, and N4 are as follows:

[0035]

[0036] A computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the method for calculating the vertical load of the trestle structure column piles as described in any one of the claims.

[0037] An electronic device, the device comprising:

[0038] One or more processors;

[0039] Memory, used to store one or more programs;

[0040] When the one or more programs are executed by the one or more processors, the one or more processors implement any of the methods described above for calculating the vertical load of the trestle structure column piles. Beneficial effects:

[0041] This calculation method can be used to determine the magnitude of the vertical load on the column pile, thereby verifying whether the strength of the column pile meets the requirements, which is of certain significance in terms of safety.

[0042] This also provides a reference for determining whether the column piles need reinforcement under subsequent changes in live load. Attached Figure Description

[0043] Figure 1 This is a schematic diagram of the vertical load distribution of the two-way slab of the trestle in one embodiment of the present invention.

[0044] Figure 2 This is a top view of a trestle bridge and schematic diagrams of pillars at different locations, representing an embodiment of the present invention.

[0045] Figure 3 This is a schematic diagram of the vertical load on each column pile according to one embodiment of the present invention.

[0046] Figure 4 This is a schematic diagram of the main view of the trestle bridge and the piles at different positions in one embodiment of the present invention.

[0047] Figure 5 This is a schematic diagram of the left view of a trestle bridge and the pillars at different positions, representing an embodiment of the present invention.

[0048] Figure 6 This is a flowchart illustrating the method for calculating the vertical load of the column piles in the trestle structure according to the present invention.

[0049] In the picture: 1. Pillar pile; 2. Two-way slab of the trestle bridge. Detailed Implementation

[0050] The present invention will be described in detail below with reference to the accompanying drawings. The objectives and effects of the invention will become clearer as a result. It should be understood that the accompanying drawings are merely illustrative and not intended to limit the scope of the invention. Figure 2 , 4 Figure 5 shows a schematic diagram of the trestle structure, illustrating the pillars at different locations. Specifically, this embodiment uses a trestle composed of 3*3 rectangular two-way slabs. As a result, the pillars under the trestle will be subjected to vertical loads. The pillars are specifically located at the four vertices of the two-way slabs of the trestle, and the vertical loads they receive vary depending on their location, specifically divided into four cases: N1, N2, N3, and N4.

[0051] The method for calculating the vertical load of the trestle structure column piles in this embodiment includes the following steps:

[0052] Step 1: Simplify to equivalent uniformly distributed load

[0053] The equivalent uniformly distributed load on the two-way slab of the trestle bridge is determined based on the equivalent absolute maximum bending moment. A unit uniformly distributed load q0 is applied to the two-way slab of the trestle bridge, and the mid-span bending moments M in the X and Y directions are calculated. x and M y for:

[0054] M x =M x0 +υM y0

[0055] M y =M y0 +υM x0

[0056] Where: M x0 M y0 This represents the mid-span bending moment in the X and Y directions when υ = 0; υ is the Poisson's ratio of the concrete.

[0057] Let's assume

[0058] Therefore, the above equation can be transformed into:

[0059] M x =(1+kυ)M x0

[0060] Therefore, the bending moment calculation coefficient β is obtained as follows:

[0061]

[0062] Then, finite element method software was used to calculate the maximum bending moment M of the plate under local loads when the arrangement was unfavorable. max The corresponding equivalent uniformly distributed load q e for:

[0063]

[0064] In the formula: l is the length of the shorter side beam of the two-way slab of the trestle bridge; M max The absolute value of the maximum bending moment in the lower span under unfavorable arrangement; k is the bending moment coefficient M in the two-way slab bending moment coefficient table. y0 With M x0 The ratio of β to υ; β is the bending moment calculation coefficient; υ is the Poisson's ratio of concrete.

[0065] Step 2: Distribute the vertical loads on the two-way slabs of the trestle bridge as follows: Figure 1 This is a schematic diagram of the vertical load distribution of the two-way slabs of the trestle bridge in this invention. Each two-way slab is divided into four sections at 45° using the plastic stranding method. The vertical load on each beam is the sum of the vertical loads within the adjacent trapezoidal or triangular areas. The maximum line load q corresponding to each beam section is:

[0066]

[0067] In the formula: α is the ratio of half the length of the short side beam of the two-way slab of the trestle bridge to the length of the long side beam of the two-way slab of the trestle bridge; l0 is the length of the long side beam of the two-way slab of the trestle bridge; q is the height of the vertical load within the area of ​​the trapezoid or triangle.

[0068] Step 3: Calculate the vertical load on the beam

[0069] Simplifying the vertical loads within the trapezoidal area of ​​the long-side beam and the triangular area of ​​the short-side beam into uniformly distributed loads based on the principle of equal support bending moments, the uniformly distributed loads q1 and q2 of the long-side beam are:

[0070] q1=(1-2α 2 +α 3 )q

[0071]

[0072] The vertical load Q1 on the long side beam is:

[0073] Q1=q1l0=(1-2α 2 +α 3 )ql0

[0074] The vertical load Q2 on the short beam is:

[0075]

[0076] Step 4: Distribute the vertical load on the beam to the column piles.

[0077] like Figure 3The load transferred from the beams to the column piles varies at different locations. The vertical loads on the column piles are divided into N1, N2, N3, and N4. N1 is the column pile bearing two beams (the intersection of one short beam and one long beam). N2 and N3 are the column piles bearing three beams (N2 is the intersection of two long beams and one short beam, N3 is the intersection of one long beam and two short beams), and N4 is the column pile bearing four beams (the intersection of two long beams and two short beams).

[0078]

[0079] The plastic stranding method used in step 2 simplifies the complex stress situation of the two-way slab of the trestle bridge under vertical loads, distributing the vertical loads to the beams according to a certain pattern, which greatly reduces the calculation difficulty. Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, or computer program products. Therefore, the present invention can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0080] This invention is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart illustrations and / or block diagrams. Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0081] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0082] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0083] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention.

[0084] All modifications and equivalent substitutions made within the spirit and principles of the invention should be included within the scope of protection of the invention.

Claims

1. A method for calculating the vertical load of a trestle structure column pile, characterized by, The method comprises the following steps: Step 1: The two-way slab of the trestle is simplified as equivalent uniform load according to the equivalent maximum bending moment ; Step 2: According to the equivalent uniform load obtained The vertical load on the two-way plate of the trestle is distributed to obtain the corresponding maximum linear load q on each beam section. Step 3: calculating the vertical load on the beam according to the line load q; Step 4: distributing the vertical load on the beam to the column piles; In the step 3, the vertical load on the beam is divided into the vertical load on the long side beam : Short edge beam under vertical load : In the formula: is the ratio of one-half the length of the short side beam of the trestle two-way slab to the length of the long side beam of the trestle two-way slab; is the length of the long side beam of the trestle two-way slab; is the uniform load of the long side beam, is the uniform load of the short side beam; In step 4, the distribution to the column piles is different in different positions of the beam, and the load transmitted to the column piles is different, which is divided into the following three cases: 1) a column pile carrying two intersecting beams ; 2) a column pile carrying three intersecting beams and in particular two long side beams intersecting one short side beam one long side beam intersecting two short side beams ; 3) a column pile carrying four intersecting beams ; The , , , The calculation method of is: wherein is the absolute value of the maximum bending moment in the span under unfavorable arrangement; is the bending moment coefficient in the table of two-way slab bending moment coefficients is the ratio of represents the midspan bending moment in the X direction when represents the midspan bending moment in the Y direction when is the bending moment calculation coefficient; is the Poisson's ratio of concrete.​ 2. The computational method of claim 1, wherein, In step 1, the equivalent uniform load Specifically: In the formula: is the length of the short beam of the two-way deck of the trestle.

3. The computational method of claim 2, wherein, The The calculation formula is: The calculation formula is: wherein is the unit uniform load applied on the two-way slab of the trestle bridge; , by , obtained, and is the X-direction and Y-direction mid-span bending moment.

4. The computational method of claim 2, wherein, In step 2, the calculation method of the line load q is as follows: The distribution is to divide each two-way deck slab of the trestle into four parts at 45° according to the plastic strand method, and the vertical load borne by each beam is the sum of the vertical loads in the adjacent trapezoidal or triangular areas.

5. The computational method of claim 1, wherein, The and The calculation method is: The vertical load in the trapezoidal area of the long-side beam and the vertical load in the triangular area of the short-side beam are respectively simplified into uniform loads according to the principle that the bending moments at the supports are equal. 。 6. A computer-readable storage medium having stored thereon a computer program, characterized in that, The program is executed by the processor to realize the trestle structure column pile vertical load calculation method according to any one of claims 1-5.

7. An electronic device, comprising: The device comprises: One or more processors; Memory for storing one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors realize the trestle structure column pile vertical load calculation method according to any one of claims 1-5.

Images