A method for embedding inclined piles in exposed bedrock at sea

Abstract

The present invention relates to a method for embedding oblique piles in exposed bedrock at sea, comprising: step S1, studying geological data, verifying on site according to the geological data, and drilling verification; step S2, calculating the thickness X and range of the artificial bed filling according to geological and hydrological data; step S3, filling bagged gravel and bagged sand according to the thickness X and filling range of the artificial bed filling to form an artificial bed; step S4, driving an oblique pile foundation; step S5, setting up a steel platform, reinforcing the oblique pile foundation, and completing the pile stabilization; step S6, drilling holes in bedrock; and step S7, constructing rock-embedded cast-in-place piles. The present invention forms an artificial bed by filling bagged gravel and bagged sand, thereby achieving pile stabilization measures for the pile foundation, while shortening the construction period and saving construction costs.

Description

Technical Field

[0001] The invention relates to a method for embedding inclined piles in offshore exposed bedrock. Background Art

[0002] Pile foundation, as a basic form of building, is widely used in offshore buildings (structures). At present, the speed of infrastructure construction in my country has entered the fast lane, and the high-quality coastline suitable for pile driving construction has been basically exhausted. As the troika driving the sustainable development of the economy, it is necessary to continue to develop my country's infrastructure, make full use of my country's coastline, and study the feasibility of building (structures) in harsh hydrological and geological environments to facilitate the people and continue to contribute to the healthy development of my country's economy. For this reason, rock-embedded cast-in-place pile foundation will be particularly important.

[0003] Due to the influence of the seabed topography, the bedrock is buried at a shallow depth or has basically no covering layer, which is not enough to form the geological conditions of the pile foundation itself. In particular, the pile foundation of some buildings (structures) not only has to withstand axial pressure, but also needs to overcome the pull-out force and horizontal force or moment. The pile foundation is usually designed as an inclined pile with a certain slope, so the inclined rock-embedded construction technology has also come into being. When carrying out the inclined pile-embedded rock construction in the above-mentioned exposed bedrock, pile stabilization measures must be taken to ensure the stability of the pile foundation (pile foundation or casing) itself and create conditions for subsequent construction.

[0004] Installing a reinforced concrete casing on the bedrock, filling the casing with medium-coarse sand and vibrating it to make it dense, using the reinforced concrete casing as a construction platform for rock-embedded piles, and embedding the pile foundation in the casing is a traditional construction process. Although this process is relatively mature and has successful examples, it has the following defects: ⑴ There are many construction procedures and complex processes; ⑵ The bedrock needs to be leveled first, and the diving operation volume is large; ⑶ High safety risks; ⑷ The installation of large reinforced concrete casings requires reliance on large equipment; ⑸ The construction period is long; ⑹ The construction cost is high.

[0005] Aiming at the insufficiency and technical defects of traditional construction technology, a method for embedding inclined piles in exposed bedrock at sea is provided. Summary of the invention

[0006] The purpose of the present invention is to overcome the existing defects and provide a method for embedding inclined piles in exposed bedrock at sea, which forms an artificial bed by throwing bagged gravel and bagged sand to achieve pile foundation stabilization measures, shorten the construction period and save construction costs.

[0007] The technical solution to achieve the above purpose is:

[0008] A method for embedding oblique piles in exposed bedrock at sea, comprising:

[0009] Step S1, studying geological data, verifying on-site according to the geological data, and drilling verification;

[0010] Step S2, calculating the thickness X and range of the artificial bed fill according to geological and hydrological data;

[0011] Step S3, filling bagged gravel and bagged sand according to the filling thickness X and filling range of the artificial bed to form an artificial bed;

[0012] Step S4, driving an inclined pile foundation;

[0013] Step S5, setting up a steel platform to reinforce the inclined pile foundation and complete the pile stabilization;

[0014] Step S6, bedrock drilling;

[0015] Step S7: rock-embedded cast-in-place pile construction.

[0016] Preferably, in step S2, the thickness X of the artificial foundation dumping is greater than the minimum burial depth h of the inclined pile foundation; the minimum burial depth h of the inclined pile foundation is affected by the water flow force F w 、Wave force P w , Active earth pressure E a , passive earth pressure E p , the influence of the deadweight of the inclined pile foundation G1 and the deadweight of the water in the inclined pile foundation G2.

[0017] Preferably, the water flow force F w The calculation formula is,

[0018]

[0019] In the formula, F w is the standard value of water flow force, C ω is the water flow resistance coefficient, ρ is the water density, which is 1.0 for fresh water and 1.025 for seawater, V is the design flow velocity of the water, which is determined based on the hydrological data of the construction site, and A is the projection area of ​​the calculation component on the plane perpendicular to the flow direction.

[0020] Preferably, the maximum velocity force component and the maximum inertia force component acting on the entire height of the inclined pile foundation are considered in the following situations:

[0021] When H / d≤0.2 and d / L≥0.2 or H / d>0.2 and d / L≥0.35, consider that the entire inclined pile foundation has the same height section, and calculate the P of the inclined pile foundation. Dmax and its moment M on the bottom surface Dmax When z1=0 and z1=d+η max , calculate the P of the inclined pile foundation Imax and its moment M on the bottom surface Imax When z1=0 and z1=d+η max -H / 2, the calculation formula is,

[0022]

[0023]

[0024]

[0025]

[0026] In the formula, C D is the velocity force coefficient, which is 1.2 for circular sections, C M is the inertia coefficient, which is 2.0 for the circular section, γ is the water density, D is the diameter of the pile foundation, H is the wave height in the construction area, K1 and K2 are the calculation coefficients, A is the cross-sectional area of ​​the pile foundation, z1 and z2 are the heights of the calculation points above the water bottom, L is the wavelength, d is the water depth at the construction point, and η max is the height of the wave crest above the still water surface;

[0027] When H / d≤0.2 and d / L<0.2 or H / d>0.2 and d / L<0.35, the positive wave force acting on the entire inclined pile foundation is calculated as above, and P Dmax Multiply by the coefficient α, for M Dmax Multiply by the coefficient β;

[0028] When 0.04≤d / L≤0.2, for P Imax Multiply by coefficient α and then multiply by coefficient γ P , for M Imax Multiply by coefficient β and then by coefficient γ M ;

[0029] The maximum total wave force acting on the entire height of the inclined pile foundation is determined by the following method:

[0030] When P Dmax ≤0.5P Imax When the maximum total positive horizontal wave force is calculated as follows:

[0031] P max =P Imax ;

[0032] When P Dmax >0.5P Imax When the maximum total positive horizontal wave force is calculated as follows:

[0033]

[0034] p w =P max ;

[0035] Where: P Dmaxis the maximum velocity force acting on the entire pile foundation height, P Imax is the maximum inertia force acting on the entire pile foundation height, P max It is the maximum total positive horizontal wave force acting on the entire pile foundation height.

[0036] Preferably, according to Rankine's earth pressure theory, the active earth pressure E on the inclined pile foundation is a for:

[0037]

[0038] In the formula, E a is the active earth pressure, γ′ is the floating weight of the dump soil, h1 is the depth of the pile foundation into the soil assuming that the zero point of pile foundation displacement C is the pile bottom, and K a is the Rankine active earth pressure coefficient, K a =tan 2 (45°-φ / 2), φ is the internal friction angle of fill;

[0039] The passive earth pressure E on the inclined pile foundation p for:

[0040]

[0041] In the formula, E p is the passive earth pressure, K p is the Rankine passive earth pressure coefficient, K P =tan 2 (45°+φ / 2);

[0042] According to the formula of active earth pressure and passive earth pressure, the earth pressure resultant E on the inclined pile foundation can be obtained as:

[0043]

[0044] K p -K a =tan 2 (45°+φ / 2)-tan 2 (45°-φ / 2).

[0045] Preferably, the deadweight G1 of the inclined pile foundation is divided into the weight above the water surface G a and below the water surface b The calculation formula for two sections is:

[0046] G1=G a +G b ;

[0047] G a =γ1H0S1 / sinα;

[0048] G b =γ′1(H′+h1)S1 / sinα;

[0049] In the formula, γ′1 is the floating weight of the pile foundation below the water surface, γ1 is the weight of the pile foundation above the water surface, H′ is the water depth at the construction point, h1 is the depth of the pile foundation into the soil assuming that the zero point of pile foundation displacement C is the pile bottom, H0 is the height from the water surface to the pile top, S1 is the effective cross-sectional area of ​​the pile foundation, and α is the angle between the pile foundation and the base bed plane;

[0050] The calculation formula of the water deadweight G2 in the inclined pile foundation is:

[0051] G2 = γS2H1 / sinα;

[0052] Where γ is the density of water, S2 is the cross-sectional area of ​​water inside the pile, and H1 is the distance between the water surface elevation inside the pile and the water surface elevation outside the pile.

[0053] Preferably, a moment balance equation is established, and its calculation formula is as follows:

[0054] (F w +P w )(2H′ / 3+h1) / sinα+G1L1+G2L2=E(h1 / 3) / sinα;

[0055] G1L1=G a (H0 / 2+H′+h1)+G b (H′+h1) / 2;

[0056] G2L2=G2(H0 / 2+H′+h1);

[0057] In the formula, L1 is the horizontal distance from the center of gravity of the pile foundation to the zero point of displacement C, L2 is the horizontal distance from the center of gravity of the water in the pile to the zero point of displacement C, and the only variable in the equilibrium equation is h1. By solving the moment equilibrium equation with a single variable, the value of the soil penetration depth h1 of the inclined pile foundation can be obtained;

[0058] The actual displacement zero point C of the inclined pile foundation is a distance above the pile end. According to the force balance relationship, the force below the displacement zero point C can be obtained:

[0059] F p =EF w -P w -G1 / cosα-G2 / cosα;

[0060] F p is a uniformly distributed load, F p =2h2γ′h1(K p -K a ), the compensation depth h2 can be obtained;

[0061] That is, the minimum embedding depth h of the inclined pile foundation is h=h1+h2.

[0062] Preferably, in step S3, the bottom layer, top layer and side slope of the artificial base bed are made of bagged gravel, and the middle layer of the artificial base bed is made of bagged sand.

[0063] Preferably, the thickness of the bottom layer and top layer of bagged gravel of the artificial base bed is 2 meters, and the slope of the edge of the artificial base bed is 1:3.

[0064] The beneficial effects of the present invention are as follows: the present invention adopts bagged crushed stone in the bottom layer, top layer and slope of the artificial base bed to avoid water scouring, and adopts bagged sand in the middle layer to provide a better pile stabilization effect for the inclined pile foundation, replaces the original concrete casing pile stabilization technology, solves the technical difficulties of carrying out inclined pile rock embedding construction on exposed bedrock or thin overburden at sea, and shortens the construction period and saves construction costs. The thickness of the artificial base bed is calculated according to the hydrogeological conditions of the construction site and through a formula, so that the thickness of the artificial base bed is technically guaranteed and the construction safety is effectively guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0065] Figure 1 It is a flow chart of a method for embedding inclined piles in exposed bedrock at sea according to the present invention;

[0066] Figure 2 It is a simplified diagram of mechanical calculation in the present invention;

[0067] Figure 3 It is a schematic diagram of the tilting of the inclined piles during the inclined pile construction process of the present invention;

[0068] Figure 4 In the present invention, H / d is within the range of 0-0.8. max Schematic diagram of . DETAILED DESCRIPTION

[0069] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, which 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 direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance.

[0070] The present invention will be further described below in conjunction with the accompanying drawings.

[0071] like Figure 1As shown, a method for embedding inclined piles in exposed bedrock at sea comprises:

[0072] Step S1, studying geological data, conducting on-site verification based on the geological data, and drilling verification.

[0073] Step S2, calculating the thickness X and range of the artificial bed fill based on geological and hydrological data.

[0074] During the construction of offshore exposed bedrock inclined piles, since water flow and waves have a great influence on the stability of the pile foundation, it is necessary to ensure the stability of the pile foundation itself by dumping bagged gravel or bagged sand in the exposed bedrock or thinner cover areas; the thickness of the artificial bed dumping X is greater than the minimum burial depth h of the inclined pile foundation.

[0075] The instability during the construction of inclined piles is often manifested as the rotation of the pile around a certain point at the lower end. When the pile reaches a certain depth in the soil, it usually produces the following Figure 3 The inclination shown in the figure means that there is a displacement zero point C. The pile tilts forward above point C and tilts backward below point C. According to this deformation characteristic, we can first assume that the displacement zero point of the pile foundation after dumping the artificial base bed is the pile bottom, calculate the depth of the pile foundation into the ground, and then calculate the compensation depth based on the actual situation that the displacement zero point C is located a certain distance above the pile bottom, and finally determine the minimum depth h of the inclined pile embedded in the rock.

[0076] The minimum depth of inclined pile foundation h is subject to water flow force F w 、Wave force P w , Active earth pressure E a , passive earth pressure E p , the influence of the deadweight of the inclined pile foundation G1 and the deadweight of the water in the inclined pile foundation G2.

[0077] (1) Calculate the water flow force F w

[0078] According to Chapter 13 of the Port Engineering Load Code, the flow force F acting on the port engineering structure is w The calculation formula is,

[0079]

[0080] In the formula, F w is the standard value of water flow force, C ω is the water flow resistance coefficient, ρ is the water density, which is 1.0 for fresh water and 1.025 for seawater, V is the design flow velocity of the water, which is determined based on the hydrological data of the construction site, and A is the projection area of ​​the calculation component on the plane perpendicular to the flow direction.

[0081] The water flow resistance coefficient C ωThe value can be obtained by looking up the table in Table 13.0.3-1 of the "Port Engineering Load Code". When calculating the water flow force acting on multiple pile foundations arranged along the water flow direction, the water flow resistance coefficient of each pile foundation is multiplied by the corresponding shielding flow influence coefficient m1. The shielding flow influence coefficient m1 can be selected by looking up the table in Table 13.0.3-2 of the "Port Engineering Load Code". When it is necessary to consider the influence of the submerged depth and water depth of the pile foundation on the water flow force, the water flow resistance coefficient is multiplied by the corresponding submerged depth influence coefficient n1 and water depth influence coefficient n2, and the submerged depth influence coefficient n1 and water depth influence coefficient n2 are multiplied by the corresponding submerged depth influence coefficient n2. n2 can be selected according to Table 13.0.3-3 and Table 13.0.3-4 of the "Port Engineering Load Code". When it is necessary to consider the lateral influence between piles, multiply the water flow resistance coefficient by the corresponding lateral influence coefficient m2. The lateral influence coefficient m2 can be selected according to Table 13.0.3-5 of the "Port Engineering Load Code". When it is necessary to consider the influence of the oblique water flow on the pile foundation, multiply the water flow resistance coefficient by the corresponding influence coefficient m3 of the pile foundation under the action of horizontal water flow. The influence coefficient m3 can be selected according to Table 13.0.3-6 of the "Port Engineering Load Code".

[0082] (2) Calculation of wave force P w

[0083] According to Section 10.3 of the Harbor Hydrological Regulations, the effects of waves on pile foundations and pier structures, for small-scale piles with D / L or b / L ≤ 0.2, the normal force acting on the entire cross section of the column at a height z above the bottom of the water and parallel to the wave direction is composed of velocity component and inertia component; the maximum velocity component and maximum inertia component acting on the entire inclined pile foundation height are considered in the following cases:

[0084] 1) When H / d≤0.2 and d / L≥0.2 or H / d>0.2 and d / L≥0.35, consider that the entire inclined pile foundation has the same height section and calculate the P of the inclined pile foundation. Dmax and its moment M on the bottom surface Dmax When z1=0 and z1=d+η max , calculate the P of the inclined pile foundation Imax and its moment M on the bottom surface Imax When z1=0 and z1=d+η max -H / 2, the calculation formula is,

[0085]

[0086]

[0087]

[0088]

[0089] In the formula, CD is the velocity force coefficient, which is 1.2 for circular sections, C M is the inertia coefficient, which is 2.0 for the circular section, γ is the water density, D is the diameter of the pile foundation, H is the wave height in the construction area, K1 and K2 are the calculation coefficients, A is the cross-sectional area of ​​the pile foundation, z1 and z2 are the heights of the calculation points above the water bottom, L is the wavelength, d is the water depth at the construction point, and η max is the height of the wave crest above the still water surface, according to Figure 4 Interpolation selection.

[0090] 2) When H / d≤0.2 and d / L<0.2 or H / d>0.2 and d / L<0.35, the positive wave force acting on the entire inclined pile foundation is calculated as above, and P Dmax Multiply by the coefficient α, for M Dmax Multiply by the coefficient β;

[0091] 3) When 0.04≤d / L≤0.2, for P Imax Multiply by coefficient α and then multiply by coefficient γ P , for M Imax Multiply by coefficient β and then by coefficient γ M ;

[0092] The maximum total wave force acting on the entire inclined pile foundation height is determined as follows:

[0093] When P Dmax ≤0.5P Imax When the maximum total positive horizontal wave force is calculated as follows:

[0094] P max =P Imax ;

[0095] When P Dmax >0.5P Imax When the maximum total positive horizontal wave force is calculated as follows:

[0096]

[0097] P w =P max ;

[0098] Where: P Dmax is the maximum velocity force acting on the entire pile foundation height, P Imax is the maximum inertia force acting on the entire pile foundation height, P max It is the maximum total positive horizontal wave force acting on the entire pile foundation height.

[0099] (3) Calculation of active earth pressure E a and passive earth pressure E p

[0100] To simplify the calculation, the bagged gravel is considered as uniform cohesive-free soil. Assuming that the zero point C of the pile foundation displacement is the pile bottom, according to Rankine's earth pressure theory, the active earth pressure E on the inclined pile foundation is a for:

[0101]

[0102] In the formula, E a is the active earth pressure, γ′ is the floating weight of the dump soil, h1 is the depth of the pile foundation into the soil assuming that the zero point of pile foundation displacement C is the pile bottom, and K a is the Rankine active earth pressure coefficient, K a =tan 2 (45°-φ / 2), φ is the internal friction angle of fill;

[0103] Passive earth pressure E on inclined pile foundation p for:

[0104]

[0105] In the formula, E p is the passive earth pressure, K p is the Rankine passive earth pressure coefficient, K P =tan 2 (45°+φ / 2);

[0106] According to the formula of active earth pressure and passive earth pressure, the earth pressure resultant E on the inclined pile foundation can be obtained as:

[0107]

[0108] K p -K a =tan 2 (45°+φ / 2)-tan 2 (45°-φ / 2).

[0109] (4) Calculate the deadweight of the inclined pile foundation G1 and the deadweight of the water in the inclined pile foundation G2

[0110] The deadweight of the inclined pile foundation G1 is divided into G above the water surface a and below the water surface b The calculation formula for two sections is:

[0111] G1=G a +G b ;

[0112] G a =γ1H0S1 / sinα;

[0113] G b=γ′1(H′+h1)S1 / sinα;

[0114] In the formula, γ′1 is the floating weight of the pile foundation below the water surface, γ1 is the weight of the pile foundation above the water surface, H′ is the water depth at the construction point, h1 is the depth of the pile foundation into the soil assuming that the zero point of pile foundation displacement C is the pile bottom, H0 is the height from the water surface to the pile top, S1 is the effective cross-sectional area of ​​the pile foundation, and α is the angle between the pile foundation and the base bed plane;

[0115] The calculation formula for the deadweight of water in the inclined pile foundation G2 is:

[0116] G2 = γS2H1 / sinα;

[0117] Where γ is the density of water, S2 is the cross-sectional area of ​​water inside the pile, and H1 is the distance between the water surface elevation inside the pile and the water surface elevation outside the pile.

[0118] (5) Establish the moment balance equation and calculate the pile foundation penetration depth h1

[0119] according to Figure 2 As shown, take the moment of the displacement zero point C and establish the moment balance equation as follows:

[0120] (F w +P w )(2H′ / 3+h1) / sinα+G1L1+G2L2=E(h1 / 3) / sinα;

[0121] G1L1=G a (H0 / 2+H′+h1)+G b (H′+h1) / 2;

[0122] G2L2=G2(H0 / 2+H′+h1);

[0123] In the formula, L1 is the horizontal distance from the center of gravity of the pile foundation to the zero point C of displacement, L2 is the horizontal distance from the center of gravity of the water in the pile to the zero point C of displacement, and the only variable in the equilibrium equation is h1. By solving the moment equilibrium equation with a single variable, the value of the depth h1 of the inclined pile foundation can be obtained.

[0124] (6) Calculate the compensation depth h2

[0125] According to the actual construction situation, the actual displacement zero point C of the inclined pile foundation is a distance above the pile end. According to the force balance relationship, the force below the displacement zero point C can be obtained:

[0126] F p =EF w -P w -G1 / cosα-G2 / cosα;

[0127] F p is a uniformly distributed load, Fp =2h2γ′h1(K p -K a ), the compensation depth h2 can be obtained.

[0128] (7) Calculate the minimum burial depth h

[0129] h=h1+h2.

[0130] Combined with the above calculations, the minimum burial depth of the inclined pile foundation is h. In actual application, in order to ensure safety, a certain margin can be added to the calculated minimum burial depth h of the pile foundation to determine the thickness X of the artificial base bed.

[0131] Step S3, filling bagged gravel and bagged sand according to the filling thickness and filling range of the artificial base bed to form an artificial base bed.

[0132] In the embodiment, the bottom layer, top layer and side slope of the artificial base bed are made of bagged gravel to avoid water erosion, and the middle layer of the artificial base bed is made of bagged sand to provide better pile stabilization effect for the pile foundation; wherein the gravel in the bagged gravel is medium-coarse sand.

[0133] In the embodiment, the thickness of the bagged gravel in the bottom and top layers of the artificial base bed is 2 meters, and the slope of the artificial base bed is 1:3; first, 2 meters of bagged gravel is laid on the bottom layer of the artificial base bed, then bagged sand is laid on the middle layer, and finally 2 meters of bagged gravel is laid on the top layer of the artificial base bed.

[0134] In another embodiment, the middle layer of the artificial base bed is made of bagged soil.

[0135] In another embodiment, the thickness of the bagged gravel on the top and bottom layers of the artificial base bed can be determined according to the on-site water flow scouring conditions.

[0136] In another embodiment, the slope of the artificial bed can be adjusted according to the actual situation on site.

[0137] Step S4, driving inclined pile foundation and entering the artificial base bed.

[0138] Step S5, setting up a steel platform, reinforcing the inclined pile foundation, and completing the pile stabilization.

[0139] Step S6, drilling a hole in the bedrock, setting up a drilling rig platform, and using the support of the drilling rig platform to perform a drilling process on the bedrock.

[0140] Step S7: rock-embedded cast-in-place pile construction.

[0141] The present invention effectively solves the technical problem of carrying out inclined pile rock embedding construction on exposed bedrock or thin overburden at sea, while shortening the construction period and saving construction costs.

[0142] The above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that the technical solutions described in the above embodiments may still be modified, or some or all of the technical features may be replaced by equivalents. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for embedding oblique piles in exposed bedrock at sea, characterized in that: include: Step S1, studying geological data, verifying on-site according to the geological data, and drilling verification; Step S2, calculating the thickness X and range of the artificial bed fill according to geological and hydrological data; Step S3, filling bagged gravel and bagged sand according to the filling thickness X and filling range of the artificial bed to form an artificial bed; Step S4, driving an inclined pile foundation; Step S5, setting up a steel platform to reinforce the inclined pile foundation and complete the pile stabilization; Step S6, bedrock drilling; Step S7, rock-embedded cast-in-place pile construction; In step S2, the thickness X of the artificial foundation filling is greater than the minimum burial depth h of the inclined pile foundation; the minimum burial depth h of the inclined pile foundation is affected by the water flow force F w 、Wave force P w , Active earth pressure E a , passive earth pressure E p , the influence of the deadweight of the inclined pile foundation G1 and the deadweight of the water in the inclined pile foundation G2; The water flow force F w The calculation formula is, In the formula, F w is the standard value of water flow force, C ω is the water flow resistance coefficient, ρ is the water density, which is 1.0 for fresh water and 1.025 for seawater, V is the design flow velocity, which is determined based on the hydrological data of the construction site, and A is the projection area of ​​the calculation component on the plane perpendicular to the flow direction; The maximum velocity component and the maximum inertia component acting on the entire height of the inclined pile foundation are considered in the following cases: When H / d≤0.2 and d / L≥0.2 or H / d>0.2 and d / L≥0.35, consider that the entire inclined pile foundation has the same height section, and calculate the P of the inclined pile foundation. Dmax and its moment M on the bottom surface Dmax When z1=0 and z1=d+η max , calculate the P of the inclined pile foundation Imax and its moment M on the bottom surface Imax When z1=0 and z1=d+η max -H / 2, the calculation formula is, In the formula, C D is the velocity force coefficient, which is 1.2 for circular sections, C M is the inertia coefficient, which is 2.0 for the circular section, γ is the water density, D is the diameter of the pile foundation, H is the wave height in the construction area, K1 and K2 are the calculation coefficients, A is the cross-sectional area of ​​the pile foundation, z1 and z2 are the heights of the calculation points above the water bottom, L is the wavelength, d is the water depth at the construction point, and η max is the height of the wave crest above the still water surface; When H / d≤0.2 and d / L<0.2 or H / d>0.2 and d / L<0.35, the positive wave force acting on the entire inclined pile foundation is calculated as above, and P Dmax Multiply by the coefficient α, for M Dmax Multiply by the coefficient β; When 0.04≤d / L≤0.2, for P Imax Multiply by coefficient α and then multiply by coefficient γ P , for M Imax Multiply by coefficient β and then by coefficient γ M ; The maximum total wave force acting on the entire height of the inclined pile foundation is determined by the following method: When P Dmax ≤0.5P Imax When the maximum total positive horizontal wave force is calculated as follows: P max =P Imax ; When P Dmax >0.5P Imax When the maximum total positive horizontal wave force is calculated as follows: P w =P max ; Where: P Dmax is the maximum velocity force acting on the entire pile foundation height, P Imax is the maximum inertia force acting on the entire pile foundation height, P max is the maximum total positive horizontal wave force acting on the entire pile foundation height; According to Rankine's earth pressure theory, the active earth pressure E on the inclined pile foundation is a for: In the formula, E a is the active earth pressure, γ′ is the floating weight of the dump soil, h1 is the depth of the pile foundation into the soil assuming that the zero point of pile foundation displacement C is the pile bottom, and K a is the Rankine active earth pressure coefficient, K a =tan 2 (45°-φ / 2), φ is the internal friction angle of fill; The passive earth pressure E on the inclined pile foundation p for: In the formula, E p is the passive earth pressure, K p is the Rankine passive earth pressure coefficient, K P =tan 2 (45°+φ / 2); According to the formula of active earth pressure and passive earth pressure, the earth pressure resultant E on the inclined pile foundation can be obtained as: K p -K a =tan 2 (45°+φ / 2)-tan 2 (45°-φ / 2); The deadweight G1 of the inclined pile foundation is divided into two parts: Ga above the water surface and Gb below the water surface. The calculation formula is: G1=G a +G b ; G a =γ1H0S1 / sinα; G b =γ′1(H′+h1)S1 / sinα; In the formula, γ′1 is the floating weight of the pile foundation below the water surface, γ1 is the weight of the pile foundation above the water surface, H′ is the water depth at the construction point, h1 is the depth of the pile foundation into the soil assuming that the zero point of pile foundation displacement C is the pile bottom, H0 is the height from the water surface to the pile top, S1 is the effective cross-sectional area of ​​the pile foundation, and α is the angle between the pile foundation and the base bed plane; The calculation formula of the water deadweight G2 in the inclined pile foundation is: G2 = γS2H1 / sinα; In the formula, γ is the gravity of water, S2 is the cross-sectional area of ​​water inside the pile, and H1 is the distance between the water surface elevation inside the pile and the water surface elevation outside the pile; The torque balance equation is established, and its calculation formula is as follows: (F w +P w )(2H′ / 3+h1) / sinα+G1L1+G2L2=E(h1 / 3) / sinα; G1L1=G a (H0 / 2+H′+h1)+G b (H′+h1) / 2; G2L2=G2(H0 / 2+H′+h1); In the formula, L1 is the horizontal distance from the center of gravity of the pile foundation to the zero point of displacement C, L2 is the horizontal distance from the center of gravity of the water in the pile to the zero point of displacement C, and the only variable in the equilibrium equation is h1. By solving the moment equilibrium equation with a single variable, the value of the soil penetration depth h1 of the inclined pile foundation can be obtained; The actual displacement zero point C of the inclined pile foundation is a distance above the pile end. According to the force balance relationship, the force below the displacement zero point C can be obtained: F p =E-F w -P w -G1 / cosα-G2 / cosα; F p is a uniformly distributed load, F p =2h2γ′h1(K p -K a ), the compensation depth h2 can be obtained; That is, the minimum embedding depth h of the inclined pile foundation is h=h1+h2.

2. The method for embedding oblique piles in exposed bedrock at sea according to claim 1, characterized in that: In step S3, the bottom layer, top layer and side slope of the artificial base bed are made of bagged gravel, and the middle layer of the artificial base bed is made of bagged sand.

3. The method for embedding oblique piles in exposed bedrock at sea according to claim 2, characterized in that: The thickness of the bagged gravel at the bottom and top layers of the artificial base bed is 2 meters, and the slope of the artificial base bed is 1:3.

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