Calculation method, device and storage medium for vibratory compaction of coral sand foundation bearing capacity

Abstract

This invention discloses a method, apparatus, and storage medium for calculating the bearing capacity of coral sand vibratory compaction foundations. The calculation method includes: determining the initial void ratio of the original coral sand on-site; performing multi-stage vibratory compaction on the foundation; testing the void ratio and effective reinforcement depth of the coral sand after vibratory compaction based on the energy of each stage of compaction; determining the energy dissipation coefficient of coral sand particle breakage through drop weight tests; establishing a formula for calculating the ultimate bearing capacity of coral sand to calculate the bearing capacity; and adjusting reinforcement parameters or optimizing load distribution. This calculation method couples the void ratio and particle breakage energy dissipation of coral sand to the bearing capacity calculation formula. On-site load plate measurements show that the bearing capacity calculation results after incorporating the characteristics of coral sand have small errors compared with on-site verification, meeting engineering design requirements and can be directly used in the reinforcement design calculation of coral sand foundations, significantly reducing the deviation of traditional design calculation results. In addition, this method is highly operable, economical, and computationally efficient, making it suitable for deep-sea island and reef engineering design applications.

Description

Technical Field

[0001] This invention relates to the fields of marine geological engineering, geotechnical engineering, and port engineering, and is particularly applicable to the calculation and design of the bearing capacity of foundations after vibratory compaction reinforcement of island and reef airports, wharves, and storage yards using highly porous and easily broken coral sand as filler. Specifically, it refers to a method, device, and storage medium for calculating the bearing capacity of coral sand vibratory compaction reinforced foundations. Background Technology

[0002] For foundation engineering of airports, docks and storage yards on islands and reefs, the transportation cost and turnaround time of foundation filler account for a large part of the project. Coral sand and reef rocks are readily available materials for island and reef foundation engineering, and coral sand is the first choice for foundation filler.

[0003] The bearing capacity of the foundation is an important indicator in the design and calculation of the foundation. The existing calculation of the bearing capacity of the foundation reinforced by vibratory compaction is mainly based on the "Technical Specification for Foundation Treatment of Buildings" (JGJ 79) or the Terzaghi ultimate bearing capacity formula. However, in the vibratory compaction reinforcement of the foundation, the degree and mechanism of vibratory compaction of coral sand foundations are different from those of sand and gravel foundations and clay foundations. Due to the characteristics of high porosity and easily broken particles, coral sand has additional energy dissipation and strength gain effects during vibratory compaction. Therefore, the bearing capacity result of coral sand calculated according to the traditional Terzaghi ultimate bearing capacity formula has a large error. According to field measurements, the error can reach 30% to 50%. Design calculation based on the traditional formula will lead to overly conservative construction of island and reef projects and insufficient safety risk management.

[0004] Therefore, this paper provides a calculation method for the bearing capacity of coral sand vibratory compaction foundation that can explicitly quantify the "porosity-particle crushing coupling effect", which is of vital importance for island and reef engineering design. Summary of the Invention

[0005] The purpose of this invention is to overcome the deficiencies of the prior art and provide a method, apparatus and storage medium for calculating the bearing capacity of coral sand vibratory compaction reinforced foundation, so as to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the technical solution of the present invention is as follows:

[0007] A method for calculating the bearing capacity of a coral sand vibratory compaction reinforced foundation includes the following steps and contents:

[0008] S1. On-site measurement of the initial porosity of the original coral sand. ;

[0009] S2. According to the design of the vibratory compaction test points, the foundation is compacted by multi-stage vibratory compaction.

[0010] S3. Test the porosity of the coral sand after vibratory compaction at each level of energy for foundation reinforcement. And calculate the corresponding effective reinforcement depth. ;

[0011] S4. Determine the energy consumption coefficient for coral sand particle crushing based on drop weight test. ;

[0012] S5. Establish the formula for calculating the ultimate bearing capacity of coral sand, and calculate the bearing capacity of the coral sand foundation after reinforcement under various levels of vibration and impact energy. :

[0013] ;

[0014] in, B represents the density of coral sand, and B represents the width of the foundation. The first bearing capacity coefficient of coral sand, This is the second bearing capacity coefficient of coral sand;

[0015] S6. Based on the comparative analysis results of the foundation's design load and the bearing capacity after reinforcement, adjust the reinforcement parameters or optimize the load distribution.

[0016] According to one aspect of this disclosure, the maximum internal friction angle of coral sand is measured. Internal friction angle after vibration under various vibration energy levels ,Establish - Regional Relationship:

[0017] ;

[0018] in, The maximum internal friction angle of coral sand, These are the friction angle fitting coefficients;

[0019] The first bearing capacity coefficient in the formula for calculating the ultimate bearing capacity of coral sand is the internal friction angle after vibratory compaction. First bearing capacity coefficient The second bearing capacity coefficient is the internal friction angle after vibration impact. The second bearing capacity coefficient below .

[0020] According to one aspect of this disclosure, the experimental energy consumption coefficient is determined by indoor particle crushing energy consumption testing. The energy consumption coefficient of the test was obtained by regression calculation of the drop weight test. Comparative test energy consumption coefficient and test energy consumption coefficient If the deviation between the two is less than 10%, then the energy consumption coefficient for coral sand particle crushing is... Otherwise, the energy consumption coefficient for coral sand particle crushing is... .

[0021] According to one aspect of this disclosure, the particle crushing energy consumption test is based on a high-pressure triaxial apparatus to determine the particle crushing energy consumption under a preset stepped confining pressure. With breakage rate Establish energy consumption for particle crushing With breakage rate Relationship:

[0022] ;

[0023] in, The energy consumption impact coefficient for crushing; crushing rate. , This represents the area of ​​the original gradation curve of the coral sand. This represents the area of ​​change in coral sand gradation under stepped confining pressure;

[0024] Calculate the test energy consumption coefficient based on the particle crushing energy consumption test. :

[0025] .

[0026] According to one aspect of this disclosure, the energy consumption test for particle crushing includes the following steps:

[0027] A1. Oblique stress under stepped confining pressure was collected using a high-pressure triaxial apparatus. Mean stress Body strain and axial strain During the test, the strain rate was controlled at 0.1% / mm, and the test termination value was 25% axial strain.

[0028] A2. Calculate the total input energy. :

[0029] ;

[0030] A3. Calculate elastic energy storage :

[0031] ;

[0032] Where K is the bulk modulus and G is the shear modulus; For body strain The elastic strain during the elastic strain stage, For axial strain Elastic strain during the elastic strain stage;

[0033] A4. According to the formula Calculate the energy consumption of particle crushing.

[0034] According to one aspect of this disclosure, in the particle crushing energy consumption test, the dry density of the coral sand sample is controlled based on 50% of the relative density.

[0035] According to one aspect of this disclosure, the vibration energy is From the formula Calculate the effective reinforcement depth .

[0036] A calculation apparatus for performing a method to calculate the bearing capacity of a coral sand vibratory compaction foundation includes:

[0037] The test data acquisition module is used to collect the result data of all tests;

[0038] The calculation module contains the calculation formula for the ultimate bearing capacity of coral sand and the calculation formula for each of its parameters. It receives data from the test data acquisition module and performs calculations.

[0039] The output module, based on the load-bearing capacity calculation results from the calculation module and combined with the design load, outputs a load-bearing capacity cloud map and a layout optimization map.

[0040] A storage medium storing a computer program, which, when executed by a processor, enables the calculation of the bearing capacity of a coral sand vibratory compaction foundation.

[0041] Compared with the prior art, the method, apparatus and storage medium for calculating the bearing capacity of coral sand vibratory compaction foundation of the present invention have the following beneficial effects:

[0042] This calculation method couples the porosity and particle crushing energy consumption of coral sand into the bearing capacity calculation formula. Field load plate measurements show that the bearing capacity calculation results after incorporating the characteristics of coral sand have small errors compared with the field verification, meeting the engineering design requirements. It can be directly used in the reinforcement design calculation of coral sand foundations, significantly reducing the deviation of traditional design calculation results. In addition, this method is highly operable, economical, and has high calculation efficiency, making it suitable for deep-sea island and reef engineering design applications. Attached Figure Description

[0043] Figure 1 This is a flowchart of the calculation method for the bearing capacity of coral sand vibratory compaction foundation disclosed in this invention. Detailed Implementation

[0044] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are merely the best embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0045] The term "embodiment" as used herein means that a particular method, step, or content described in connection with an embodiment may be included in at least one embodiment of the invention. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a mutually exclusive, independent, or alternative embodiment. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0046] This embodiment provides a method for calculating the bearing capacity of coral sand vibratory compaction reinforced foundation, such as... Figure 1 As shown, it includes the following steps and contents:

[0047] S1. On-site measurement of the initial porosity of the original coral sand. In this embodiment, the porosity determination combines the ring cutter method and the nucleus-free density meter. The ring cutter method has high testing accuracy but low efficiency, while the nucleus-free density meter is suitable for large-area rapid on-site detection, but its detection accuracy is generally low. The porosity determination logic is to use the ring cutter method as the standard, calibrate the nucleus-free density meter, verify and expand the detection range, and finally determine the average porosity by "ring cutter standard value + calibrated nucleus-free density meter qualified value".

[0048] S2. Set multiple vibratory compaction energy levels, divide the distribution of foundation measuring points, prevent mutual interference between different energy zones, and vibratory compact each measuring point;

[0049] S3. Determine the porosity of the coral sand after vibration compaction at the center position of each measuring point. Porosity after vibratory compaction Determine the porosity ratio using the method described in step S1;

[0050] Determine the effective reinforcement depth of each measuring point The effective reinforcement depth can be obtained through existing in-situ penetration tests or layered sampling inspections, or it can be calculated using Menard's empirical formula. This embodiment prefers the calculated value, based on the different levels of vibration energy at each measuring point. The effective reinforcement depth is based on the formula. calculate, Coral sand is heavily flammable;

[0051] S4. Determine the energy consumption coefficient for coral sand particle crushing. :

[0052] Traditionally, a drop weight test is used to determine the impact strength. The drop weight is 20 kg, and the drop height is 0.5 m-2.5 m. The impact strength is divided into five levels. The crater volume and rebound energy difference are measured, and the test energy dissipation coefficient is obtained by regression calculation. ;

[0053] Given that the drop weight test differs from the loading mechanism in actual engineering scenarios and is significantly affected by the particle state at the test point, its testing accuracy is insufficient. Furthermore, for fragile coral sand, the test results are distorted. Therefore, this example embodiment also provides a method for determining the energy consumption coefficient through indoor particle breakage energy consumption testing. :

[0054] Determine the energy consumption of particle crushing under various confining pressures. With Hardin's breakage rate Establish energy consumption for particle crushing With breakage rate Relationship:

[0055] ;

[0056] Obtain the energy consumption influence coefficient of crushing Then test the energy consumption coefficient The calculation formula is:

[0057] ;

[0058] Among them, the particle crushing energy consumption test is based on a high-pressure triaxial apparatus, which includes energy consumption calculation and particle crushing rate calculation. The energy consumption calculation is used to determine the crushing energy consumption. Particle breakage rate calculation is used to determine the breakage rate under the corresponding confining pressure. Both are carried out simultaneously, and the test includes the following steps;

[0059] A1. The confining pressure of the high-pressure triaxial apparatus shall not be less than 2 MPa, and the confining pressure steps shall be set to four levels: 100 kPa, 200 kPa, 400 kPa, and 800 kPa. The high-pressure triaxial apparatus shall be able to automatically record and collect the deviatoric stress under the stepped confining pressure. Mean stress Body strain and axial strain During the test, the strain rate was controlled at 0.1% / mm. Since coral sand reaches its critical state at 25% axial strain, therefore... As the energy input termination quantity;

[0060] The high-pressure triaxial apparatus can also simultaneously sieve the gradation of coral sand particles under each test confining pressure, and determine and calculate the gradation change area of ​​coral sand particles based on Hardin's core logic of breakage rate. ;

[0061] A2. Based on the collected parameter values, the total input energy is obtained by trapezoidal integration. :

[0062] ;

[0063] A3. Calculate the elastic energy stored in the coral sand particles during the elastic deformation stage. :

[0064] ;

[0065] Where K is the bulk modulus and G is the shear modulus, which are obtained from the resilient modulus test of coral sand; For body strain The elastic strain during the elastic strain stage, For axial strain Elastic strain during the elastic strain stage;

[0066] A4. Therefore, the energy consumption of particle crushing is obtained. ;

[0067] Based on the area of ​​the original gradation curve of the coral sand collected before the experiment and the area of ​​gradation change under each step of confining pressure. Calculate the breakage rate ;

[0068] It should be noted that in the particle crushing energy consumption test, the dry density of the coral sand sample was controlled based on 50% of its relative density, i.e. and made Size; Controlling the dry density to 50% relative density first requires collecting coral sand on-site, determining its maximum and minimum porosity, and then using the core formula of relative density to deduce the target dry density.

[0069] Energy consumption coefficient of coral sand particle crushing The determination of the energy consumption coefficient in conjunction with testing and test energy consumption coefficient When the deviation between the two is less than 10%, it indicates that the on-site geological consistency is good, which is suitable for determining the energy consumption of particle crushing through drop weight test. Therefore, the energy consumption coefficient for coral sand particle crushing is... Otherwise, the energy consumption coefficient determined indoors shall be used for testing. Assign an energy consumption coefficient to the crushing of coral sand particles, i.e. .

[0070] S5. Integrating the effects of particle crushing energy consumption coefficient and porosity variation, a calculation formula for the ultimate bearing capacity of coral sand is established, and the bearing capacity of the coral sand foundation after reinforcement is calculated under various levels of vibratory impact energy. :

[0071] ;

[0072] in, B represents the density of coral sand, and B represents the width of the foundation. The first bearing capacity coefficient of coral sand, This is the second bearing capacity coefficient of coral sand;

[0073] In this example embodiment, to adapt to the characteristics of coral sand in different regions and further improve the accuracy of the bearing capacity calculation formula, the first bearing capacity coefficient in the above coral sand ultimate bearing capacity calculation formula is... Second bearing capacity coefficient , respectively corresponding to the internal friction angle of the rammed coral sand First bearing capacity coefficient Second bearing capacity coefficient ;

[0074] Determining the maximum internal friction angle of coral sand Internal friction angle after vibration under various vibration energy levels A regional database of coral sand in this area was established, and a system was built. - Regional empirical formulas reduce the steps required for on-site internal friction angle measurement, facilitating rapid engineering design calculations for the same or adjacent regions.

[0075] ;

[0076] in, These are the friction angle fitting coefficients;

[0077] S6. Finally, based on the comparative analysis results of the foundation's design load and the bearing capacity after reinforcement, adjust the reinforcement parameters for different load areas. For example, in areas with dense loads, adjust the vibration energy and vibration spacing appropriately to enable them to obtain a bearing capacity with a certain safety factor. Alternatively, in areas with concentrated loads, optimize the design load distribution to transfer or homogenize the concentrated loads.

[0078] A computing apparatus for performing a method to calculate the bearing capacity of a coral sand vibratory compaction foundation includes:

[0079] The test data acquisition module is used to collect the results of indoor and field tests such as porosity determination, drop weight test, particle crushing energy consumption test, and coral sand internal friction angle determination.

[0080] The calculation module contains the calculation formula for the ultimate bearing capacity of coral sand and the calculation formula for each parameter. It receives data from the test data acquisition module and performs calculations.

[0081] The output module, based on the load-bearing capacity calculation results from the calculation module and combined with the design load, outputs a load-bearing capacity cloud map and a load distribution optimization map that change in real time with the porosity, according to the principle of uniform load distribution.

[0082] Application Example: Designing the foundation reinforcement construction for an airport runway on an island reef according to the above calculation methods and steps:

[0083] The initial porosity of the coral sand on the reef was... =1.1, Coral Sand Heavy =10KN / m 3 The vibration energy at a specific test point is calculated based on the vibration frequency and vibration time. =1500KJ, calculated to obtain the effective reinforcement depth =6m; Experimental energy consumption coefficient obtained from on-site testing. =0.25, porosity after vibratory compaction =0.7; Angle of internal friction of coral sand after vibration impact =44.8°, then the corresponding =185, =134, B=2m; Energy consumption test of particle crushing and calculation to obtain the test energy consumption coefficient. =0.28, ,but = ; Calculate the bearing capacity of the coral sand foundation after reinforcement. =2230 kPa, on-site implementation The actual measured load on the plate was 2200 kPa, and the calculation error was less than 2%.

[0084] Through the above description of the embodiments, those skilled in the art can clearly understand that the various embodiments of this application can be implemented by means of software or software combined with necessary general-purpose hardware platforms, and of course, they can also be implemented by hardware functions. Based on this understanding, the technical solution of this application, in essence or the part that contributes to the prior art, can be embodied in the form of a software product. The software product is stored in a storage medium and includes several instructions to cause a computer device, such as including but not limited to a personal computer, server, or network device, to execute all or part of the steps of the method described in any embodiment of this application.

[0085] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for calculating the bearing capacity of a ground foundation reinforced by vibro-replacement of coral sand, characterized in that, The method comprises the following steps and contents: S1, in situ determination of initial porosity ratio of raw coral sand ; S2, according to the vibration test experimental point design, the foundation is carried out multi-stage vibration compaction; S3, after the ground is reinforced by testing the vibration energy of each level, the corresponding porosity of coral sand after vibration , and the corresponding effective reinforcement depth is calculated ; S4. Determine the energy dissipation coefficient of coral sand particle breakage according to the drop weight test ; S5, establish the formula for calculating the ultimate bearing capacity of coral sand, calculate the bearing capacity of the foundation after reinforcement under the vibration energy of each level : ； wherein, B is a base width of the foundation, B is a base width of the foundation, B is a base width of the foundation, S6, according to the design load of the foundation and the comparative analysis result of the bearing capacity after reinforcement, adjust the reinforcement parameters or optimize the load distribution.

2. The method for calculating the bearing capacity of a coral sand vibro-reinforced foundation according to claim 1, characterized in that: determining the maximum internal friction angle of the coral sand the internal friction angle after the vibration under each level of the vibration energy , establishing - regional relationship ； wherein is the friction angle fitting coefficient; The first bearing capacity coefficient in the formula for calculating the ultimate bearing capacity of coral sand is the corresponding internal friction angle after vibratory compaction. First bearing capacity coefficient The second bearing capacity coefficient is the internal friction angle after vibration impact. The second bearing capacity coefficient below .

3. The method for calculating the bearing capacity of a coral sand vibro-reinforced foundation according to claim 1, characterized in that: determining a test energy dissipation coefficient by indoor particle breakage energy dissipation test , the test energy dissipation coefficient is determined by the fall weight test regression calculation , comparing the test energy dissipation coefficient and the test energy dissipation coefficient , both deviations are less than 10%, then the coral sand particle breakage energy dissipation coefficient , otherwise, the coral sand particle breakage energy dissipation coefficient .

4. The method for calculating the bearing capacity of a coral sand vibro-reinforced foundation according to claim 3, characterized in that: The particle breakage energy consumption test is based on a high-pressure triaxial apparatus, and determines the particle breakage energy consumption under a preset stepwise confining pressure The breakage rate , and establishes a relationship formula between the particle breakage energy consumption and the breakage rate ​ ； wherein, is the crushing energy dissipation influence coefficient; the crushing rate , is the original grading curve area of the coral sand, is the step confining pressure change area of the coral sand grading calculating the test energy consumption coefficient according to the particle breakage energy consumption test : 。 5. The method for calculating the bearing capacity of a coral sand vibro-reinforced foundation according to claim 4, characterized in that: The particle crushing energy dissipation test comprises the following steps: A1. Collecting the deviatoric stress under the stepwise confining pressure by high-pressure triaxial apparatus , average stress , bulk strain , and axial strain ; the strain rate was controlled at 0.1% / mm during the test, and 25% of the axial strain was taken as the test termination value; A2, calculate total input energy : ； A3, calculating elastic energy storage : ； where K is the bulk modulus and G is the shear modulus; for the bulk strain elastic strain at the elastic strain stage, for the axial strain elastic strain at the elastic strain stage; A4. Calculate the energy consumed by the particle breakage according to the formula .​ 6. The method for calculating the bearing capacity of a coral sand vibro-reinforced foundation according to claim 5, characterized in that: In the particle crushing energy dissipation test, the dry density of the coral sand sample is controlled according to 50% relative density.

7. The method for calculating the bearing capacity of a coral sand vibro-reinforced foundation according to claim 1, characterized in that: The shock energy is The effective reinforcement depth is calculated by the formula .​ 8. A computing device for performing the method of calculating the bearing capacity of a coral sand vibro-reinforced foundation according to any one of claims 1 to 7, characterized in that, It comprises: A test data acquisition module for acquiring the result data of all tests; A calculation module embedded with the coral sand ultimate bearing capacity calculation formula and its parameter calculation formula, receiving the data of the test data acquisition module and performing calculation; An output module, according to the bearing capacity calculation result of the calculation module, combining the design load, outputting the bearing capacity cloud chart and the distribution optimization chart.

9. A storage medium having stored therein a computer program, characterized in that: The computer program is executed by the processor, which can realize the steps of the coral sand vibration reinforcement foundation bearing capacity calculation method in any one of claims 1-7.

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