Calculation method of vertical stress and critical height for pile-cap-beam supported embankments

Abstract

An embodiment of the present invention provides a method for calculating the vertical stress and critical height of a pile cap beam supported embankment. By obtaining the backfill parameters, pile layout design parameters and roadbed top surface design load of the pile cap beam supported embankment, the vertical stress of the pile cap beam supported embankment at a given depth is calculated using a vertical stress calculation formula. By obtaining the backfill parameters, pile layout design parameters, roadbed top surface design load and actual backfill height of the pile cap beam supported embankment, the theoretical critical height of the equal subsidence surface is calculated using a critical height calculation formula, and the theoretical critical height of the equal subsidence surface is corrected in combination with the actual backfill height of the pile cap beam supported embankment to obtain the actual critical height of the equal subsidence surface. The present invention proposes that the critical height of the equal subsidence surface is not only related to the backfill parameters and pile layout design parameters of the embankment, but is also positively correlated with the actual backfill height of the embankment and the roadbed top surface design load, making the calculation of the critical height of the equal subsidence surface more accurate.

Description

Technical Field

[0001] Embodiments of the present invention relate to the technical field of research on soil arching effect of pile-cap-beam supported embankments. More specifically, embodiments of the present invention relate to a method for calculating vertical stress and critical height for pile-cap-beam supported embankments. Background Art

[0002] This section is intended to provide background or context for embodiments of the present invention as recited in the claims. The description herein may include concepts that could be explored, but not necessarily concepts that have been previously conceived or explored. Therefore, unless otherwise indicated herein, the material described in this section is not prior art with respect to the specification and claims of this application and is not admitted to be prior art by inclusion in this section.

[0003] Long-term experience in domestic engineering projects has revealed that pile-supported yield zones, when used to treat deep soft soil foundations, particularly those lacking an overlying hard crust, still present a certain risk of instability, even when meeting overall stability verification requirements. Rigid pile composite foundations in deep soft soils can suffer not only overall stability failure but also "flow-sliding failure." Pile-beam (PB) composite foundations and pile-cap-beam (PCB) composite foundations can be employed to promote soil arching, increase the lateral stiffness of the pile top, and enhance the bending strength of the rigid piles, thereby leveraging the high vertical bearing capacity of rigid pile composite foundations. Ground beam or pile-cap-ground beam structures are similar to rigid raft structures installed at the top of the piles. While they do not directly increase the bearing capacity of the foundation, they enhance the bearing capacity of rigid pile composite foundations by promoting the transfer of fill load to the pile top (soil arching effect), increasing the lateral stiffness of the pile top, the bending strength of the pile body, and controlling differential settlement at the pile top.

[0004] In situ observations of the composite yield zone of a pile-cap-beam structure (PCB structure) were conducted through a physical engineering project. The results demonstrate that the PCB structure is significantly effective in reducing lateral displacement of the foundation, overall settlement of the pile and surrounding soil, and differential settlement. Therefore, the composite yield zone of the PCB structure is considered highly effective in improving yield zone stability. In rigid pile composite foundations, the soil settlement at the top of the foundation is often greater than at the pile tops. This differential settlement generates shear stress in the roadbed filler, transferring vertical stress from the soil between the piles to the pile tops. This load transfer phenomenon is known as soil arching. Studying the soil arching effect of PCB structures can help designers clarify the load-sharing ratio or stress reduction rate at the pile tops of pile-supported composite foundations, thereby more accurately determining the required bearing capacity of the foundation piles and the size and stiffness of the foundation beam structure.

[0005] However, there is currently limited research on the load transfer mechanism of PCB structures, and relatively little research on soil arching under conditions of equilateral triangular pile layouts and circular pile caps. Although it is generally believed that the critical height of the equal settlement surface (the height from the equal settlement surface to the top of the foundation or the top of the pile cap) is related to many factors (such as the fill parameters of the embankment and the pile spacing), the currently proposed calculation formula for the critical height of the equal settlement surface basically only depends on the pile spacing or the clear distance between piles. This can cause a large deviation between the theoretical and actual values of the soil arching effect under certain working conditions. In addition, there are currently some calculation methods that use a fixed critical height. However, the theoretical values of the foundation top surface tension and stress reduction rate derived by this method deviate significantly from the experimental values when the fill height is high. Summary of the Invention

[0006] The existing research on soil arching effect of pile-cap-beam supported embankments has the above-mentioned drawbacks. Therefore, a method for calculating vertical stress and critical height of pile-cap-beam supported embankments is highly desirable to address at least one of the above-mentioned drawbacks.

[0007] In this context, embodiments of the present invention are intended to provide a method for calculating vertical stress and critical height for a pile-cap-beam supported embankment.

[0008] In a first aspect of an embodiment of the present invention, a method for calculating vertical stress of a pile cap beam supported embankment is provided, comprising: obtaining backfill parameters, pile layout design parameters and roadbed top surface design load of the pile cap beam supported embankment; the backfill parameters include cohesion, internal friction angle and density of each soil layer in the embankment; the pile layout design parameters include pile layout method, pile spacing, pile cap radius and ground beam width; the pile layout method is equilateral triangle pile layout; based on the backfill parameters, pile layout design parameters and roadbed top surface design load, the vertical stress of the pile cap beam supported embankment at a given depth is calculated using a vertical stress calculation formula; the vertical stress calculation formula is a relationship between the vertical stress of the pile cap beam supported embankment and its backfill parameters, pile layout design parameters, roadbed top surface design load and embankment depth.

[0009] In one embodiment, the vertical stress calculation formula is: Where Z is the depth of the embankment, σ Z is the vertical stress of the pile cap beam supported embankment at depth Z, γ is the soil density, c, are the cohesion and internal friction angle of the fill, K0 is the lateral pressure coefficient of the soil, Q is the design load on the top surface of the roadbed, P is the vertical projection area of the yield zone of the pile cap beam structure, and G is the circumference of the yield zone of the pile cap beam structure.

[0010] In another embodiment, the lateral pressure coefficient K0 of the soil is:

[0011] In yet another embodiment, the vertical projection area P of the yielding region of the pile cap beam structure is: Where D is the pile spacing, r is the pile cap radius, and w is the ground beam width.

[0012] In yet another embodiment, the perimeter G of the yielding region of the pile cap beam structure is:

[0013] G=3D-6r+6.8w.

[0014] In a second aspect of the embodiment of the present invention, a method for calculating the critical height of a pile cap beam supported embankment is provided, comprising: obtaining fill parameters, pile layout design parameters, roadbed top surface design load and actual fill height of the pile cap beam supported embankment; the fill parameters include the cohesion, internal friction angle and density of each soil layer in the embankment; the pile layout design parameters include the pile layout method, pile spacing, pile cap radius and ground beam width; the pile layout method is an equilateral triangle pile layout; based on the fill parameters, pile layout design parameters, roadbed top surface design load and actual fill height, the theoretical critical height of the equal subsidence surface is calculated using a critical height calculation formula; the critical height calculation formula is a relationship between the equal subsidence surface critical height of the pile cap beam supported embankment and its fill parameters, pile layout design parameters, roadbed top surface design load and actual fill height; the theoretical critical height of the equal subsidence surface is corrected in combination with the actual fill height of the pile cap beam supported embankment to obtain the actual critical height of the equal subsidence surface.

[0015] In one embodiment, the critical height calculation formula is: Where h f is the theoretical critical height of the equal sinking surface, P is the vertical projection area of the pile cap beam structure yield area, G is the perimeter of the pile cap beam structure yield area, K0 is the lateral pressure coefficient of the soil, γ is the specific gravity of the soil, c, are the cohesion and internal friction angle of the fill, Q is the design load on the top surface of the roadbed, and h is the actual fill height of the pile cap beam supported embankment.

[0016] In another embodiment, the theoretical critical height of the equal subsidence surface is corrected in combination with the actual fill height of the pile cap beam supported embankment, including: if the theoretical critical height of the equal subsidence surface is less than the actual fill height, then the actual critical height of the equal subsidence surface is equal to the theoretical critical height of the equal subsidence surface; if the theoretical critical height of the equal subsidence surface is greater than the actual fill height, then the actual critical height of the equal subsidence surface is equal to the actual fill height.

[0017] In yet another embodiment, the lateral pressure coefficient K0 of the soil is:

[0018] In yet another embodiment, the vertical projection area P of the yielding region of the pile cap beam structure is: The perimeter G of the yield zone of the pile cap beam structure is: G = 3D-6r+6.8w, where D is the pile spacing, r is the pile cap radius, and w is the ground beam width.

[0019] The beneficial effects of the present invention include: by studying the load transfer mechanism of the pile cap beam structure, the present invention obtains a method for calculating the vertical stress of a pile cap beam supported embankment at any depth under the conditions of equilateral triangle pile layout and circular pile cap.

[0020] Furthermore, the present invention proposes additional factors that determine the critical height of the equal settlement surface for pile-cap-beam supported embankments. Specifically, it proposes that the critical height of the equal settlement surface is not only related to the embankment's fill parameters and pile layout design parameters, but also positively correlated with the embankment's actual fill height and the design load on the roadbed top surface. Compared to existing methods that only consider pile spacing or pile clearance, the critical height calculated by the present invention is more accurate.

[0021] In addition, since the present invention takes into account the influence of the actual fill height of the embankment when calculating the equal settlement surface critical height, compared with the existing calculation method using a fixed critical height, it can reduce the problem of large deviations between the theoretical value and the experimental value of the tension and stress reduction rate of the top surface of the foundation when the embankment fill height is high.

[0022] At the same time, the present invention only uses easily obtainable embankment fill parameters, pile layout design parameters, fill height, and load conditions during calculation, is easy to implement, and has high practical value in engineering. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The above and other objects, features and advantages of the exemplary embodiments of the present invention will become readily apparent by reading the following detailed description with reference to the accompanying drawings, in which several embodiments of the present invention are shown by way of example and not limitation, in which:

[0024] Figure 1 A flowchart of a vertical stress calculation method 100 for a pile cap beam supported embankment according to one embodiment of the present invention is schematically shown;

[0025] Figure 2 Schematically showing basic physical parameter diagrams of various soil layers according to an embodiment of the present invention;

[0026] Figure 3-1 Schematically shows a foundation reinforcement scheme diagram according to an embodiment of the present invention;

[0027] Figure 3-2 Schematically shows a pile layout design parameter diagram according to an embodiment of the present invention;

[0028] Figure 3-3Schematically shows a schematic diagram of the installation position of the monitoring instrument for an engineering case according to an embodiment of the present invention;

[0029] Figure 4-1 Schematically shows a top view of a pile cap beam structure composed of regular triangular piles according to an embodiment of the present invention;

[0030] Figure 4-2 A schematic three-dimensional view of a pile cap beam structure composed of regular triangle piles according to an embodiment of the present invention is shown;

[0031] Figure 5-1 Schematically shows a schematic diagram of a catenary arch model according to an embodiment of the present invention;

[0032] Figure 5-2 Schematically shows a unit body force analysis diagram of a catenary arch model according to an embodiment of the present invention;

[0033] Figure 6 Schematically shows a flow chart of a critical height calculation method 600 for a pile cap beam supported embankment according to another embodiment of the present invention;

[0034] Figure 7 Schematically shows the stress distribution diagram of soil between piles at different depths when the fill height is 8m according to an embodiment of the present invention;

[0035] In the drawings, the same or corresponding reference numerals denote the same or corresponding parts. DETAILED DESCRIPTION

[0036] The principles and spirit of the present invention will be described below with reference to several exemplary embodiments. It should be understood that these embodiments are provided solely to enable those skilled in the art to better understand and implement the present invention, and are not intended to limit the scope of the present invention in any way. Rather, these embodiments are provided to make this disclosure more thorough and complete, and to fully convey the scope of the present disclosure to those skilled in the art.

[0037] According to an embodiment of the present invention, a method for calculating the vertical stress and critical height of a pile-cap beam-supported embankment is proposed. Furthermore, the numbers of any elements in the accompanying drawings are for illustrative purposes only and are not intended to be limiting. Furthermore, any nomenclature is provided for distinction only and does not have any limiting meaning.

[0038] The principles and spirit of the present invention are explained in detail below with reference to several representative embodiments of the present invention.

[0039] This study, based on the long-term stress and deformation characteristics of a pile cap and ground beam test section, analyzes the mechanism by which the ground beam structure improves foundation bearing capacity and anti-settlement deformation performance. The existing friction arch model is then improved to adapt it to triangular friction arches. The theoretical calculation method for soil arching in pile cap and beam structures is revised, and a method for calculating critical height is derived through discussion and analysis.

[0040] After introducing the basic principles of the present invention, various non-limiting embodiments of the present invention are described in detail below.

[0041] Reference below Figure 1 This section describes a method for calculating vertical stress in a pile-cap-beam-supported embankment according to an exemplary embodiment of the present invention. It should be noted that the embodiments of the present invention can be applied to any applicable scenario involving calculating the vertical stress of soil arching in a pile-cap-beam-supported embankment.

[0042] Figure 1 A flowchart of a vertical stress calculation method 100 for a pile-cap-beam supported embankment according to an embodiment of the present invention is schematically shown, which includes step S101 and step S102.

[0043] In step S101, the fill parameters, pile layout design parameters and roadbed top surface design load of the pile cap beam supported embankment are obtained.

[0044] Among them, the fill parameters of pile cap beam supported embankment (hereinafter referred to as embankment fill parameters) include: cohesion c of each soil layer in the embankment, internal friction angle and gravity γ. For example, embankment fill parameters can be determined through on-site geotechnical testing. Standard geotechnical testing is currently available and includes, for example, in-situ shear testing and indoor direct shear testing, which will not be discussed in detail here.

[0045] Figure 2 The parameters shown are the basic physical parameters of various soil layers obtained through geotechnical tests on site. Figure 2 The cohesion c and internal friction angle of various soil layers can be obtained wait.

[0046] The pile layout design parameters include: pile layout method, pile spacing D, pile cap radius r and ground beam width w. The pile cap radius r can be measured directly, or the pile cap diameter R can be measured first and then converted from the pile cap diameter R.

[0047] In this embodiment, the pile arrangement is a regular triangle (plum blossom) pile arrangement (such as Figure 3-2 ), which includes 3 circular pile caps, which are distributed in a regular triangle and connected by ground beams.

[0048] In step S102, based on the fill parameters, pile layout design parameters and roadbed top surface design load obtained in step S101, the vertical stress calculation formula is used to calculate the vertical stress of the pile cap beam supported embankment at a given depth.

[0049] The vertical stress calculation formula is the relationship between the vertical stress of the pile cap beam supported embankment and its fill parameters, pile layout design parameters, roadbed top surface design load and embankment depth.

[0050] In this embodiment, the vertical stress calculation formula is as follows:

[0051]

[0052] Where Z is the depth of the embankment, σ Z is the vertical stress of the pile cap beam supported embankment at depth Z, γ is the soil density, c, where is the cohesion and internal friction angle of the fill, respectively; K0 is the lateral pressure coefficient of the soil; and Q is the design load on the top surface of the roadbed. P is the vertical projection area of the yield zone of the pile cap beam structure; and G is the perimeter of the yield zone of the pile cap beam structure.

[0053] in, D is the pile spacing, r is the pile cap radius, and w is the ground beam width.

[0054] The vertical stress calculation formula in this embodiment is obtained by Figure 4-1 and Figure 4-2 The pile cap beam structure (PCB structure for short) composed of equilateral triangle piles shown is obtained by stress analysis. Figure 4-1 This is a top view of the PCB structure. Figure 4-1 The area within the dotted line is defined as a unit, in which the soil directly above the pile cap and the ground beam is considered a rigid wall. Figure 4-1 If the soil within the range of the black thick solid line yields, the area within the black thick solid line is the yield area of the PCB structure, the vertical projection area of the yield area is P, and the perimeter is G. Figure 4-2 This is a three-dimensional view of the PCB structure. In order to facilitate stress analysis of the plastic zone, Figure 4-2 The rigid earth wall is not drawn. Figure 4-2 The total fill height of the middle embankment is h. A thin slice of soil with a thickness of dz is taken at a depth Z below the top of the fill. By performing a vertical force balance analysis on this thin slice of soil, the above vertical stress calculation formula can be obtained. This calculation formula can be used to calculate the vertical stress at any depth of the pile-cap-beam supported embankment.

[0055] In this embodiment, the calculation formula of the soil lateral pressure coefficient K0 is:

[0056]

[0057] Where, is the internal friction angle of fill.

[0058] The calculation formula of the lateral pressure coefficient K0 in this embodiment is obtained by Figure 5-1 The force balance analysis of a triangular microelement on the catenary arch wall is shown in Figure 5-2 ), and is obtained by combining the Mohr circle and the lateral pressure coefficient. Figure 5-1 In the figure, the soil between the rigid walls sinks fully, and the sliding surface reaches the plastic limit state, making the wall rough. According to the Mohr circle, the direction of the principal stress on the wall surface is deflected. Let the angle of rotation be θ, which is related to the roughness of the wall.

[0059] As another embodiment, the existing lateral pressure coefficient calculation formula may also be used to calculate the excavated lateral pressure coefficient K0.

[0060] In summary, by studying the load transfer mechanism of the pile cap beam structure, the present invention obtains a method for calculating the vertical stress at any depth of a pile cap beam supported embankment under the conditions of equilateral triangle pile layout and circular pile cap.

[0061] Reference below Figure 6 This section describes a method for calculating the critical height of a pile-cap-beam supported embankment according to an exemplary embodiment of the present invention. It should be noted that the embodiments of the present invention can be applied to any applicable scenario, including any scenario involving calculating the critical height of the equal subsidence surface (i.e., the height from the equal subsidence surface to the top surface of the foundation) of a pile-cap-beam supported embankment.

[0062] Figure 6 A flowchart of a critical height calculation method 600 for a pile cap beam supported embankment according to an embodiment of the present invention is schematically shown, which includes step S601, step S602 and step S603.

[0063] In step S601, the fill parameters, pile layout design parameters, roadbed top surface design load and actual fill height of the pile cap beam supported embankment are obtained.

[0064] The method for obtaining the fill parameters, pile layout design parameters and roadbed top surface design load of the pile cap beam supported embankment in step S601 is the same as that in step S101 and will not be repeated here.

[0065] In step S602, based on the fill parameters, pile layout design parameters, roadbed top surface design load and actual fill height obtained in step S601, the theoretical critical height of the equal settlement surface (i.e., the theoretical value of the critical height of the equal settlement surface) is calculated using the critical height calculation formula.

[0066] Among them, the critical height calculation formula is the relational expression between the critical height of the equal settlement surface of the embankment supported by the pile cap beam and its filling parameters, pile layout design parameters, the designed load on the embankment top surface, and the actual filling height.

[0067] In this embodiment, the critical height calculation formula is as follows:

[0068]

[0069] In the formula, h f is the theoretical critical height of the equal settlement surface, P is the area of the vertical projection of the yield area of the pile cap beam structure, G is the perimeter of the yield area of the pile cap beam structure, K0 is the coefficient of lateral earth pressure, γ is the unit weight of soil, c, are respectively the cohesion and internal friction angle of the filling, Q is the designed load on the embankment top surface, and h is the actual filling height of the embankment supported by the pile cap beam. Among them, G = 3D - 6r + 6.8w, where D is the pile spacing, r is the radius of the pile cap, and w is the width of the ground beam.

[0070] The critical height calculation formula in this embodiment is obtained by analyzing the forces on the Figure 4-2 element. The critical height calculation formula of the present invention shows that the critical height of the equal settlement surface is not only related to the filling parameters and pile layout design parameters of the embankment supported by the pile cap beam, but also related to the actual filling height h of the embankment and the designed load Q on the embankment top surface, etc.

[0071] In step S603, the theoretical critical height of the equal settlement surface is corrected in combination with the actual filling height of the embankment supported by the pile cap beam to obtain the actual critical height of the equal settlement surface.

[0072] Specifically, let h f be the theoretical critical height of the equal settlement surface, h be the actual filling height of the embankment supported by the pile cap beam, and h fc be the actual critical height of the equal settlement surface. Then: when h f < h, h fc = h f ; when h f > h, h fc = h.

[0073] In summary, the present invention comprehensively considers four factors when calculating the actual critical height of the equal settlement surface, namely: the fill parameters of the pile cap beam supported embankment, the pile layout design parameters, the actual fill height and the roadbed top surface design load. Among them, the fill parameters of the embankment reflect the influence of the fill properties (i.e. cohesion, internal friction angle, density) on the critical height of the equal settlement surface; the pile layout design parameters reflect the influence of the pile layout structure (i.e. pile spacing, pile cap radius, ground beam width) on the critical height of the equal settlement surface; the actual fill height of the embankment reflects the influence of the fill height on the critical height of the equal settlement surface; and the roadbed top surface design load reflects the influence of the load conditions on the critical height of the equal settlement surface.

[0074] It can be seen from this that the method of the present invention has the following advantages:

[0075] (1) The present invention proposes additional factors that determine the critical height of the equal settlement surface of a pile-cap-beam supported embankment. Specifically, it proposes that the critical height of the equal settlement surface is not only related to the fill parameters and pile layout design parameters of the embankment, but is also positively correlated with the actual fill height of the embankment and the design load on the roadbed top surface. Compared with the prior art method for calculating the critical height of the equal settlement surface that only considers the pile spacing or pile clearance, the critical height of the equal settlement surface calculated by the present invention is more accurate.

[0076] (2) Since the present invention takes into account the influence of the actual fill height of the embankment when calculating the critical height of the equal settlement surface, compared with the existing calculation method using a fixed critical height, it can reduce the problem of large deviations between the theoretical value and the experimental value of the tension and stress reduction rate of the top surface of the foundation when the fill height of the embankment is high.

[0077] (3) The present invention only uses easily obtainable embankment fill parameters, pile layout design parameters, fill height, and load conditions during calculation, which is easy to implement and has high practical value in engineering.

[0078] The effectiveness of the method of the present invention is verified by using specific application examples below.

[0079] In a specific application scenario, the fill type of a pile cap beam supported embankment is plain fill. The basic physical parameters of the plain fill include: the density of the plain fill is γ = 17.6KN / m 3 , cohesion is c = 18kPa, internal friction angle is The foundation reinforcement scheme of the pile cap beam supported embankment is as follows Figure 3-1 As shown, from top to bottom are: 1.8m plain fill, 11.6m silt, 14m silty clay, 5.2m sand, etc. Figure 3-2 It can be obtained that the pile layout design parameters of the pile cap beam supported embankment are: regular triangle pile layout, pile spacing D = 4m, pile cap diameter R = 2m, ground beam width w = 0.3m, and the pile cap radius r = 1m can be calculated from the pile cap diameter R.

[0080] The internal friction angle Substituting the calculation formula of the side pressure coefficient K0, the side pressure coefficient can be obtained

[0081] Critical height h f for:

[0082] At this time: z =114kPa(Z=-5.9m).

[0083] The stress distribution diagram of soil between piles at different depths when the actual fill height h = 8m is as follows: Figure 7 As shown in FIG, the effectiveness of the method of the present invention is verified by fitting the soil stress distribution between piles at different depths when the fill height is h=8m with a numerical model.

[0084] Those skilled in the art will appreciate that embodiments of the present invention may be implemented as a system, method, or computer program product. Therefore, the present disclosure may be implemented in the following forms: entirely in hardware, entirely in software (including firmware, resident software, microcode, etc.), or in a combination of hardware and software, generally referred to herein as a "circuit," "module," "unit," or "system." Furthermore, in some embodiments, the present invention may also be implemented in the form of a computer program product in one or more computer-readable media containing computer-readable program code.

[0085] Any combination of one or more computer-readable media can be used. A computer-readable medium can be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium can be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or component, or any combination thereof. More specific examples (non-exhaustive examples) of computer-readable storage media can include, for example: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium can be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, device or device.

[0086] A computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium may be transmitted using any suitable medium, including but not limited to wireless, wire, optical cable, RF, etc., or any suitable combination thereof.

[0087] The computer program code for performing the operations of the present invention can be written in one or more programming languages, or a combination thereof, including object-oriented programming languages such as Java, Smalltalk, C++, and conventional procedural programming languages such as "C" or similar programming languages. The program code can be executed entirely on the user's computer, partially on the user's computer, as a stand-alone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer can be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or can be connected to an external computer (e.g., through the Internet using an Internet service provider).

[0088] These computer program instructions can be stored in a computer-readable medium that enables a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable medium produce a product that includes an instruction device that implements the functions / operations specified in the blocks in the flowchart and / or block diagram.

[0089] Computer program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device so that a series of operational steps are performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, such that the instructions executed on the computer or other programmable apparatus provide a process that implements the functions / operations specified in the blocks in the flowchart and / or block diagram.

[0090] It should be noted that while the detailed description above describes several steps in the method for calculating vertical stress and critical height for pile-cap beam-supported embankments, this division is not mandatory. In fact, according to embodiments of the present invention, the features and functions of two or more steps described above may be embodied in a single step. Conversely, the features and functions of a single step described above may be further divided and embodied in multiple steps.

[0091] Furthermore, although the operations of the present method are described in a particular order in the accompanying drawings, this does not require or imply that the operations must be performed in that particular order, or that all of the operations shown must be performed to achieve the desired results. Rather, the steps depicted in the flowcharts may be performed in a different order. Additionally or alternatively, certain steps may be omitted, multiple steps may be combined into a single step, and / or a single step may be broken down into multiple steps.

[0092] The use of the verbs "comprise", "include" and their conjugations in the application documents does not exclude the presence of elements or steps other than those stated in the application documents. The article "a" or "an" preceding an element does not exclude the presence of a plurality of such elements.

[0093] Although the spirit and principles of the present invention have been described with reference to several specific embodiments, it should be understood that the present invention is not limited to the specific embodiments disclosed, and the division into various aspects does not mean that the features of these aspects cannot be combined to benefit. Such division is merely for the convenience of expression. The present invention is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims. The scope of the appended claims is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures and functions.

Claims

1. A method for calculating vertical stress in a pile cap beam supported embankment, characterized in that: include: Obtain fill parameters, pile layout design parameters, and roadbed top surface design load for a pile-cap-beam supported embankment; the fill parameters include the cohesion, internal friction angle, and density of each soil layer in the embankment; the pile layout design parameters include the pile layout method, pile spacing, pile cap radius, and ground beam width; the pile layout method is an equilateral triangle pile layout; The vertical stress of the pile-cap-beam supported embankment at a given depth is calculated using a vertical stress calculation formula based on the fill parameters, pile layout design parameters, and roadbed top surface design load. The vertical stress calculation formula is a relationship between the vertical stress of the pile-cap-beam supported embankment and its fill parameters, pile layout design parameters, roadbed top surface design load, and embankment depth. The vertical stress calculation formula is: ； Where Z is the depth of the embankment, is the vertical stress of the pile cap beam supported embankment at depth Z, For the weight of the soil, c 、 are the cohesion and internal friction angle of fill, is the lateral pressure coefficient of soil, Q is the design load on the top surface of the roadbed, P is the vertical projection area of the yield zone of the pile cap beam structure, G is the perimeter of the yield zone of the pile cap beam structure.

2. The vertical stress calculation method for pile cap beam supported embankment according to claim 1, characterized in that: Soil lateral pressure coefficient for: .

3. The vertical stress calculation method for pile cap beam supported embankment according to claim 2, characterized in that: The vertical projection area P of the yielding region of the pile cap beam structure is: , where D is the pile spacing, r is the pile cap radius, and w is the ground beam width.

4. The vertical stress calculation method for pile cap beam supported embankment according to claim 3, characterized in that: The perimeter G of the yielding area of the pile cap beam structure is: .

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