CN-117272706-B - Method and device for acquiring frost heaving capacity in frozen soil area, electronic equipment and storage medium

CN117272706BCN 117272706 BCN117272706 BCN 117272706BCN-117272706-B

Abstract

The invention relates to the technical field of safety treatment of natural gas transportation pipelines, and provides a method, a device, electronic equipment and a storage medium for acquiring frost heaving capacity in a frozen soil area, wherein the method comprises the steps of determining a surface temperature function; the method comprises the steps of determining a constant temperature at a first depth under the ground surface, constructing a finite element model of a calculation area of a frozen soil area according to a ground surface temperature function, the first depth and the constant temperature, applying boundary conditions to the finite element model, obtaining the time when a freezing front reaches the lower line of each layer of grids in M layers of grids from the ground surface from top to bottom within the time range of the ground surface temperature function, and determining the frost heaving amount according to the time and the temperature gradient. The frost heaving capacity can be quickly and accurately determined, and basic data can be provided for safety evaluation of buried pipelines.

Inventors

SHI LEI
ZHAO YATONG
HUANG ZIJIAN
ZHOU LIGUO

Assignees

中国石油化工股份有限公司
中石化（大连）石油化工研究院有限公司

Dates

Publication Date: 20260505
Application Date: 20220613

Claims (8)

1. The method for acquiring the frost heaving capacity in the frozen soil area is characterized by comprising the following steps of: determining a surface temperature function; Determining a constant temperature at a first depth below the surface; Constructing a finite element model of a calculation area of the frozen earth area according to the earth surface temperature function, the first depth and the constant temperature, wherein the upper boundary of the finite element model is the earth surface, the lower boundary is the first depth, and the determination principle of the left boundary and the right boundary is that the temperature gradient level change at the left boundary and the right boundary is less than K DEG C/M, and K is a preset value; Applying boundary conditions to the finite element model, and acquiring the time when a freezing front reaches each layer of grids in the M layers from top to bottom from the ground surface in the time range of the ground surface temperature function and the temperature gradient of the position where the freezing front is located; Determining a frost heave from the time and the temperature gradient; said determining a frost heave from said time and said temperature gradient comprising: Determining the frost heave according to the time and the temperature gradient by adopting the following calculation formula; ; Wherein, the In order to achieve a frozen swelling capacity, the frozen swelling powder is, For external loads, a and b are parameters related to the soil properties, In order to provide a temperature gradient, Is the amount of change in time.
2. The method of claim 1, wherein the surface temperature function comprises: ; Wherein, the Is used for controlling the temperature of the atmospheric environment, Is the average temperature of the atmosphere in the year, Is the amplitude of the change in the atmospheric temperature, Is time.
3. The method for acquiring frost heaving capacity of a frozen earth area according to claim 1, wherein the boundary conditions include insulation of left and right boundaries, constant temperature of a lower boundary, and application of an upper boundary based on the surface temperature function.
4. A frozen-earth area frost heaving capacity acquisition device, comprising: the fitting module is used for determining a surface temperature function; an acquisition module for determining a constant temperature at a first depth below the surface; The construction module is used for constructing a finite element model of a calculation area of the frozen earth area according to the earth surface temperature function, the first depth and the constant temperature, wherein the upper boundary of the finite element model is the earth surface, the lower boundary is the first depth; the calculation module is used for applying boundary conditions to the finite element model, and acquiring the time when the freezing front reaches each layer of grids in the M layers of grids from the surface from top to bottom and the temperature gradient of the position where the freezing front is located in the time range of the surface temperature function; a determination module for determining a frost heave from the time and the temperature gradient; the determining module is specifically configured to: Determining the frost heave according to the time and the temperature gradient by adopting the following calculation formula; ; Wherein, the In order to achieve a frozen swelling capacity, the frozen swelling powder is, For external loads, a and b are parameters related to the soil properties, In order to provide a temperature gradient, Is the amount of change in time.
5. The frozen earth area frost heaving capacity acquisition device according to claim 1, wherein the surface temperature function comprises: ; Wherein, the Is used for controlling the temperature of the atmospheric environment, Is the average temperature of the atmosphere in the year, Is the amplitude of the change in the atmospheric temperature, Is time.
6. The frozen earth area frost heaving capacity obtaining apparatus according to claim 1, wherein the boundary conditions include a left and right boundary being insulated, a lower boundary being a constant temperature, and an upper boundary being applied based on the surface temperature function.
7. An electronic device comprising a processor and a memory storing a computer program, characterized in that the processor implements the steps of the method for acquiring frost heaves in a frozen earth area according to any of claims 1 to 3 when executing the computer program.
8. A processor-readable storage medium, characterized in that the processor-readable storage medium stores a computer program for causing the processor to execute the steps of the method for acquiring frost heaves in a frozen earth area according to any one of claims 1 to 3.

Description

Method and device for acquiring frost heaving capacity in frozen soil area, electronic equipment and storage medium Technical Field The invention relates to the technical field of safety treatment of natural gas transportation pipelines, in particular to a method and a device for acquiring frost heaving capacity in a frozen soil area, electronic equipment and a storage medium. Background Frozen soil refers to various rocks and soils containing ice at a temperature below zero degrees celsius. The third frozen soil is about 21.5% of the area of the Chinese world, the permafrost is mainly distributed on the Qinghai-Tibet plateau with middle and low latitude, and the other permafrost is distributed on pamil, western mountain, northeast great and great Khingan and eastern. The oil and gas pipeline cannot avoid crossing the frozen soil zone, for example, the medium russian crude oil pipeline Mo River which is one of four energy strategy channels in China is from Daqing line, the whole length is 953 km, and 512 km in the north part crosses the permafrost zone. The pipeline is subjected to the pressure of medium in the pipeline, the gravity of the medium and the soil pressure, and the stress generated when the foundation is sunk and deformed due to temperature change, so that the pipeline is in a quite complex stress state. Differential frost heaving is a major cause of pipeline damage in frozen soil areas. The water in the frozen soil is frozen in winter, and the ground surface is raised due to the aggregation of the ice lens, which is called frost heaving. If the frost heaving is too great, the pipeline is caused to deform excessively to fail. When designing or safety evaluating a frozen soil area pipeline, key parameter characteristics of the frozen soil area, such as frost heaving depth and change of frost heaving amount with time, need to be obtained. In the existing method, the parameters of the frozen soil area are difficult to obtain. Disclosure of Invention Aiming at the problems existing in the prior art, the invention provides a method and a device for acquiring frost heaving capacity in a frozen soil area, electronic equipment and a storage medium. In a first aspect, the present invention provides a method for obtaining frost heaving capacity in a frozen earth region, including: determining a surface temperature function; Determining a constant temperature at a first depth below the surface; Constructing a finite element model of a calculation area of the frozen earth area according to the earth surface temperature function, the first depth and the constant temperature, wherein the upper boundary of the finite element model is the earth surface, the lower boundary is the first depth, and the determination principle of the left boundary and the right boundary is that the temperature gradient level change at the left boundary and the right boundary is less than K DEG C/M, and K is a preset value; Applying boundary conditions to the finite element model, and acquiring the time when a freezing front reaches each layer of grids in the M layers from top to bottom from the ground surface in the time range of the ground surface temperature function and the temperature gradient of the position where the freezing front is located; and determining the frost heaving amount according to the time and the temperature gradient. In one embodiment, the surface temperature function comprises: Wherein T (x, 0, T) is the atmospheric ambient temperature, T m is the annual average temperature of the atmosphere, A is the amplitude of the atmospheric temperature change, and T is the time. In one embodiment, the boundary conditions include left and right boundaries being adiabatic, a lower boundary being a constant temperature, an upper boundary being applied based on the surface temperature function. In one embodiment, said determining the frost heave from said time and said temperature gradient comprises: Determining the frost heave according to the time and the temperature gradient by adopting the following calculation formula; Where h f is the frost heaving capacity, P e is the external load, a and b are parameters related to the soil properties, gradT (t) is the temperature gradient, and V t is the time variation. In a second aspect, the present invention provides an apparatus for acquiring frost heaving capacity in a frozen earth region, comprising: the fitting module is used for determining a surface temperature function; an acquisition module for determining a constant temperature at a first depth below the surface; The construction module is used for constructing a finite element model of a calculation area of the frozen earth area according to the earth surface temperature function, the first depth and the constant temperature, wherein the upper boundary of the finite element model is the earth surface, the lower boundary is the first depth; the calculation module is used for applying boundary conditions to the finite