CN110824144A - Method for determining internal friction angle of loose accumulation body - Google Patents

Method for determining internal friction angle of loose accumulation body Download PDF

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CN110824144A
CN110824144A CN201911131727.2A CN201911131727A CN110824144A CN 110824144 A CN110824144 A CN 110824144A CN 201911131727 A CN201911131727 A CN 201911131727A CN 110824144 A CN110824144 A CN 110824144A
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loose
accumulation body
friction angle
internal friction
loose accumulation
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CN110824144B (en
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游勇
刘洋
柳金峰
李新坡
杨开成
赵曙熙
刘道川
谢艳芳
刘林
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Institute of Mountain Hazards and Environment IMHE of CAS
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Abstract

The invention provides a method for determining an internal friction angle of a loose accumulation body, which comprises the following steps: acquiring the bulk density of the loose accumulation body by field sampling; acquiring corresponding lateral static pressures of the stack at every certain stack height; the friction angle in the loose stack is calculated. According to the method, the pressure sensors are used for measuring the lateral pressure values of the loose accumulation body at different accumulation heights, the straight line slope of the lateral static pressure divided by the weight of the loose accumulation body and the accumulation height is obtained through proportional fitting, and the internal friction angle of the loose accumulation body can be obtained through inverse calculation by using a Rankine soil pressure calculation formula. Therefore, the method for determining the internal friction angle of the loose accumulation body is provided, the vacancy of the method for determining the internal friction angle of the loose accumulation body is filled, and theoretical guidance is further provided for stability judgment and engineering protection design of the loose accumulation body.

Description

Method for determining internal friction angle of loose accumulation body
Technical Field
The invention belongs to the field of mountain disaster prevention and control, and particularly relates to a method for determining an internal friction angle of a loose accumulation body.
Background
A loose stack is a non-continuous geotechnical medium that is formed by geological or man-made actions. Usually has the characteristic of obvious difference of space mechanical properties. In recent years, with the advance of national strategies such as urbanization construction, the construction of more and more infrastructures such as railways, bridges and tunnels is gradually advanced, a large number of loose accumulations generated in engineering construction are formed into loose accumulations with the height of dozens of hundred meters, and once the accumulation is unstable, the accumulation can be formed into geological disasters such as large-scale collapse and landslide, and the like, so that destructive attack is caused on downstream infrastructures and residents.
According to a Rankine soil pressure calculation formula, the selection of the internal friction angle of the soil body directly influences the calculation of the soil pressure of the soil body, so that the strength, the stability, the anti-overturning property and the like of an engineering structure are greatly influenced. The internal friction angle of the existing soil body can be measured through a triaxial compression experiment or a direct shear experiment, however, for a loose accumulation body, large particles exist in the particle composition of the loose accumulation body, so that the loose accumulation body is loose, and great difficulty exists in field sampling and indoor experiment sample preparation, therefore, the triaxial compression experiment and the direct shear experiment cannot be practical, a large-scale on-site shear experiment is adopted, the internal friction angle cannot be accurately measured due to the fact that the soil body is loose, and the experimental point cannot be accurately determined.
The research work for selecting the internal friction angle of the loose accumulation body is slow due to the reasons, and no good method for selecting the internal friction angle of the loose accumulation body at home and abroad is provided so far. The current domestic standard does not provide clear guidance for selecting the internal friction angle of the loose accumulation body, only provides the change range of the internal friction angle of certain soil, which causes great difficulty in selecting the internal friction angle of the loose accumulation body, has little difference of the internal friction angles, but causes great deviation on the calculation result of the soil pressure, so that the selection of the internal friction angle directly influences the stability judgment of the loose accumulation body and the reliability of the engineering protection design of the loose accumulation body. For this reason, the work of studying the internal friction angle of a loose stack is of great practical significance.
Disclosure of Invention
The present invention provides a method for determining the internal friction angle of a loose stack to solve at least one of the above problems.
To solve the above problems, as one aspect of the present invention, there is provided a method of determining an angle of friction in a loose stack, comprising:
acquiring the bulk density rho of a loose accumulation body through field sampling;
obtaining every predetermined height h of the stackiA lateral static pressure P ofi；
The angle of friction in the loose pile is calculated according to the following formula:
Figure BDA0002278508120000021
wherein phi is the internal friction angle, K is hiAnd PiAnd/(. rho.g) obtaining the slope of a fitted straight line by adopting direct proportion fitting, wherein g is the gravity acceleration.
Preferably, the lateral static pressure is measured by a pressure sensor provided at the predetermined height.
Preferably, the bulk density is measured according to the requirements of geotechnical test code.
In the soil pressure determination process of the loose accumulation body, the accurate acquisition of the loose accumulation body is very important, and the existing specification and research does not provide a determination method of the internal friction angle of the loose accumulation body. According to the method, the pressure sensors are used for measuring the lateral pressure values of the loose accumulation body at different accumulation heights, the straight line slope of the lateral static pressure divided by the weight of the loose accumulation body and the accumulation height is obtained through proportional fitting, and the internal friction angle of the loose accumulation body can be obtained through inverse calculation by using a Rankine soil pressure calculation formula. Therefore, the method for determining the internal friction angle of the loose accumulation body is provided, the vacancy of the method for determining the internal friction angle of the loose accumulation body is filled, and guidance is provided for stability judgment and engineering protection design of the loose accumulation body.
Drawings
FIG. 1 schematically illustrates a graph of sample 1 lateral static pressure P versus stack height h;
FIG. 2 schematically illustrates a graph of sample 2 lateral static pressure P versus stack height h;
FIG. 3 schematically shows a plot of the hydrostatic pressure to weight ratio P/(ρ g) versus the bulk height h for sample 1 and a direct scale fit straight line plot;
fig. 4 schematically shows a plot of the hydrostatic pressure to weight ratio P/(ρ g) versus the bulk height h for sample 2 and a direct scale fit straight line plot.
Detailed Description
The following detailed description of embodiments of the invention, but the invention can be practiced in many different ways, as defined and covered by the claims.
The invention aims to provide a calculation method for determining an internal friction angle phi (unit) by combining indoor experimental data and a Rankine soil pressure calculation model, which comprises the following steps:
A. the bulk density rho (unit: kg/m) of the sample is measured by sampling on site according to the requirements of geotechnical test Specification3)。
B. When samples are stacked at a certain height, measuring different heights h by using pressure sensors at certain intervalsiLateral static pressure P corresponding to (unit: m)i(unit: kPa), and P was calculatedi/(ρg)。
PiIn/(. rho.g), g is the acceleration of gravity in m/s2In this patent, 9.8m/s is taken2。
C. Drawing establishment hiAnd PiAnd (ρ g) obtaining a slope K of a fitting straight line by adopting a positive proportion fitting.
D. According to the Rankine soil pressure calculation formula, the soil active soil pressure can be calculated according to the following formula (1):
P＝ρghtan2(45゜-φ/2) (1)
obtained after modification of formula (1):
P/(ρg)＝htan2(45゜-φ/2) (2)
according to the slope K of the straight line obtained by fitting in the step C, the direct proportional relation between P/(rho g) and the height h is as follows:
P/(ρg)＝Kh (3)
the combination of (2) and (3) can obtain
K＝tan2(45゜-φ/2) (4)
And (3) inversely calculating according to the formula (4) to obtain the internal friction angle phi of the loose accumulation body as follows:
Figure BDA0002278508120000041
example (b):
the bulk density of each of the collapsed loose stacks in G318 Batang county (hereinafter referred to as sample 1) and G317 Sama county (hereinafter referred to as sample 2)2 was measured by sampling and determining as shown in Table 1.
TABLE 1 particle composition and bulk Density of collapsed Loose stacks
Figure BDA0002278508120000042
The samples were subjected to side pressure experiments to obtain side static pressures P at intervals of 1.5cm and the ratio P/(ρ g) of the side static pressure to the gravity and the stacking height h were calculated as shown in table 2.
According to the data in table 2, drawing a scatter diagram of the lateral static pressure P, the ratio of the static pressure to the gravity P/(rho g) and the stacking height h of the samples 1 and 2, and fitting the scatter diagram by adopting straight lines to obtain the slope K of each straight line, wherein the slope K is shown in fig. 1, fig. 2 and table 3; the internal friction angle φ of the sample was calculated using equation (5), and is shown in Table 3.
TABLE 2 samples 1, 2 static lateral pressures P and P/(ρ g) at each height
TABLE 3P/(ρ g) and h-scattergram straight-line fitting slope table and internal friction angle of samples 1, 2
Figure BDA0002278508120000052
At present, the research on the mechanical property of the loose accumulation body is less, and the range of the parameter is not described in detail by the current specifications and documents, so the invention selects the average mechanical index of the sand in the engineering geological manual for comparison, and the density in the engineering geological manual is 1.9-2.05kg/m3The internal friction angle of the sandy soil is 38-42 degrees, and the internal friction angles of the samples 1 and 2 calculated by the method are 39.02 degrees and 37.3 degrees respectively.
The calculation results are known from the scope agreed in engineering geological handbook, so that the determination of the friction angle in the loose accumulation body formed by collapse, landslide and the like is feasible.
The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims (3)

1. A method of determining an angle of friction in a loose stack, comprising:
acquiring the bulk density rho of a loose accumulation body through field sampling;
obtaining every predetermined height h of the stackiA lateral static pressure P ofi；
The angle of friction in the loose pile is calculated according to the following formula:
Figure FDA0002278508110000011
wherein the content of the first and second substances,
Figure FDA0002278508110000012
is an internal friction angle, K is hiAnd PiAnd/(. rho.g) obtaining the slope of a fitted straight line by adopting direct proportion fitting, wherein g is the gravity acceleration.
2. The method of claim 1, wherein said lateral static pressure is measured by a pressure sensor set at said predetermined height in the past.
3. The method of claim 1, wherein the bulk density is measured according to geotechnical test code.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112946245A (en) * 2021-03-11 2021-06-11 中国电建集团成都勘测设计研究院有限公司 Method and device for determining strength parameters of weak interlayer in red zone

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11160172A (en) * 1997-12-02 1999-06-18 Nippon Koei Co Ltd Landslide monitoring device
JP2005146692A (en) * 2003-11-17 2005-06-09 Takenaka Komuten Co Ltd Bearing capacity evaluation method
CN102831328A (en) * 2012-09-13 2012-12-19 中国环境科学研究院 Method for determining environmental-protection dredging range based on water pollution bottom mud identification and evaluation
CN102841037A (en) * 2012-09-10 2012-12-26 重庆交通大学 Method and device for testing steady repose angle of wide grading loose accumulation soil body
CN103526722A (en) * 2013-10-16 2014-01-22 中国科学院、水利部成都山地灾害与环境研究所 Debris flow gabion prevention and control structural body and design method thereof
CN104484503A (en) * 2014-11-20 2015-04-01 重庆大学 Foundation pit flexible support active earth pressure calculating method considering action point position
CN104573319A (en) * 2014-12-03 2015-04-29 中南大学 Method for designing grooving construction slurry parameters for underground diaphragm wall of water-rich sand gravel stratum based on overall stability of groove wall
CN104963328A (en) * 2015-06-29 2015-10-07 中国电建集团成都勘测设计研究院有限公司 Method for confirming internal friction angle of coarse-grained soil under large embedded depth
CN105138767A (en) * 2015-08-23 2015-12-09 北京工业大学 Deep-buried asymmetric closely spaced tunnel surrounding rock pressure calculation method
RU2016102394A (en) * 2016-01-26 2017-07-31 Евгений Николаевич Хрусталев METHOD OF HRUSTALEV E.N. DEFINITIONS OF BEARING ABILITY AND PERFORMANCE ANISOTROPY COEFFICIENT
CN108509376A (en) * 2018-03-26 2018-09-07 华东交通大学 One kind being based on the modified Calculating method of earth pressure of displacement model

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH11160172A (en) * 1997-12-02 1999-06-18 Nippon Koei Co Ltd Landslide monitoring device
JP2005146692A (en) * 2003-11-17 2005-06-09 Takenaka Komuten Co Ltd Bearing capacity evaluation method
CN102841037A (en) * 2012-09-10 2012-12-26 重庆交通大学 Method and device for testing steady repose angle of wide grading loose accumulation soil body
CN102831328A (en) * 2012-09-13 2012-12-19 中国环境科学研究院 Method for determining environmental-protection dredging range based on water pollution bottom mud identification and evaluation
CN103526722A (en) * 2013-10-16 2014-01-22 中国科学院、水利部成都山地灾害与环境研究所 Debris flow gabion prevention and control structural body and design method thereof
CN104484503A (en) * 2014-11-20 2015-04-01 重庆大学 Foundation pit flexible support active earth pressure calculating method considering action point position
CN104573319A (en) * 2014-12-03 2015-04-29 中南大学 Method for designing grooving construction slurry parameters for underground diaphragm wall of water-rich sand gravel stratum based on overall stability of groove wall
CN104963328A (en) * 2015-06-29 2015-10-07 中国电建集团成都勘测设计研究院有限公司 Method for confirming internal friction angle of coarse-grained soil under large embedded depth
CN105138767A (en) * 2015-08-23 2015-12-09 北京工业大学 Deep-buried asymmetric closely spaced tunnel surrounding rock pressure calculation method
RU2016102394A (en) * 2016-01-26 2017-07-31 Евгений Николаевич Хрусталев METHOD OF HRUSTALEV E.N. DEFINITIONS OF BEARING ABILITY AND PERFORMANCE ANISOTROPY COEFFICIENT
CN108509376A (en) * 2018-03-26 2018-09-07 华东交通大学 One kind being based on the modified Calculating method of earth pressure of displacement model

Non-Patent Citations (7)

* Cited by examiner, † Cited by third party
Title
RADOSLAW L. MICHALOWSKI ET AL.: "Coefficient of Earth Pressure at Rest", 《JOURNAL OF GEOTECHNICAL AND GEOENVIRONMENTAL ENGINEERING》 *
周旋等: "等效内摩擦角计算方法及其应用", 《水运工程》 *
王俊杰等: "相对密实度对松散堆积土体强度变形特性的影响", 《重庆交通大学学报(自然科学版)》 *
王珏等: "粮食散体物料压力计算理论对比分析", 《现代食品》 *
王辉等: "《工程荷载与可靠度设计原理》", 30 June 2017 *
陈长冰: "筒仓内散体侧压力沿仓壁分布研究", 《万方数据》 *
马克生等: "粉土在直剪试验中的强度特性研究", 《科技情报开发与经济》 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN112946245A (en) * 2021-03-11 2021-06-11 中国电建集团成都勘测设计研究院有限公司 Method and device for determining strength parameters of weak interlayer in red zone

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