CN105987869A - Saturated soft soil centrifugal seepage drum - Google Patents
Saturated soft soil centrifugal seepage drum Download PDFInfo
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- CN105987869A CN105987869A CN201610526219.4A CN201610526219A CN105987869A CN 105987869 A CN105987869 A CN 105987869A CN 201610526219 A CN201610526219 A CN 201610526219A CN 105987869 A CN105987869 A CN 105987869A
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- cylinder
- seepage
- permeable stone
- centrifugal
- soil
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume, or surface-area of porous materials
- G01N15/08—Investigating permeability, pore-volume, or surface area of porous materials
Abstract
The invention relates to a saturated soft soil centrifugal seepage drum which is used for measuring a seepage coefficient of saturated soil under the centrifugal action. The saturated soft soil centrifugal seepage drum comprises a rotating motor (60) and a glass graduated rotating cylinder (66), wherein the glass graduated rotating cylinder (66) comprises a cylinder wall with scales, and a large hollow cylindrical permeable stone and a small hollow cylindrical permeable stone (8), which are coaxial with each other and made of permeable concrete; a motor rotating shaft (4) extending out of the bottom of the cylinder is provided in the middle part; a soil sample groove (9) is formed between the inner wall of the large hollow cylindrical permeable stone (20) and the outer wall of the small hollow cylindrical permeable stone (8), filter paper (6) is adhered on the inner wall of the soil sample groove (9), and a saturated soil sample is arranged in the soil sample groove (9); and a cavity (21) is formed between the small hollow cylindrical permeable stone (80 and the motor rotating shaft (4), and external water is injected into the cavity (21). By adopting the saturated soft soil centrifugal seepage drum, the seepage solidification characteristic of the soft soil can be more accurately simulated under the action of a dynamic load.
Description
Technical field
The present invention relates to a kind of saturated soft soil and centrifuge seepage flow cylinder, particularly relate to the small-sized centrifugal of a kind of saturated soft soil infiltration coefficient of measurement under the action of the centrifugal
Seepage flow cylinder.
Background technology
Soil body penetration characteristic is the importance of Characteristics of Geotechnical Engineering research, and tolerance soil body penetration characteristic index is infiltration coefficient, and existing measurement infiltration is
The experimental provision of number mainly has constant head darcy flow instrument and varying head darcy flow instrument, and this laboratory apparatus has accuracy to sand gas permeability measurement
The advantages such as height, technology maturation.
But saturated soft soil has, and moisture content is high, compressibility high, void ratio is high, bearing capacity is low, permeate the characteristic of little " three high two low ", its seepage flow
Often show non-darcy flow characteristic.Apply existing constant head darcy flow instrument and varying head darcy flow instrument will lead weak soil gas permeability measurement
Cause result deviation engineering actual, it is impossible to instruct geotechnical engineering investigation, it is more likely that bring huge loss to geotechnical engineering design, construction.
With the continuous quickening of city process, the traffic engineering such as subway, railway, highway quickly grows, and China is built and at the High Speed Rail Projects built
Occupy first place in the world in position.Geotechnical engineering investigation more pay close attention to different frequency dynamic load to Technical Characteristics of Mild Clay and pollutant migration problem in soil, especially
In weak soil seepage characteristic problem under dynamic load and centrifugal coupling, still use existing constant head darcy flow instrument and varying head darcy flow instrument at present
It to weak soil gas permeability measurement, is not inconsistent with engineering practice, more simulating pollution thing how can not migrate in soil, lack corresponding experimental provision.
So people start increasingly to pay close attention to the research to weak soil seepage characteristic, and the achievement in research by theoretical research and engineering experience accumulation is applied to work
In journey practice.
Centrifugal machine model trial by internationally recognized for be research rock-soil dynamics problem scientific experimentation platform most effective, state-of-the-art.U.S. brother in 1931
First the sub-university of rival develops at the beginning of the geotechnical centrifuge that First radius in the world is 0.25m, 19 century 70s, geotechnical centrifuge beautiful,
English, the Soviet Union, method, Deng state develop in succession, develop turntable type centrifuge, suspended centrifugal and drum centrifuge, and China is in 19th century 80
Age starts to pay attention to power Centrifuge Techniques, and nineteen eighty-two is called for short by the Changjiang river research institute, and maximum centrifugal acceleration reaches 300g, capacity 150g-t
Effective radius 3m.Up to now, China has desk centrifuge more than 20.Test model can reflect condition and the behavior of prototype, mould truely and accurately
Need to meet geometric similarity, kinematic similitude and three primary conditions of dynamic similitude law between type and prototype, i.e. corresponding to each parameter similarity criterion and
Rapport between parameter.
Although traditional turntable type centrifuge, suspended centrifugal and drum centrifuge can reach the effect of centrifugal seepage flow, but due to operation complexity, ooze
The scale of construction of stream instrument is big, and testing expenses are high, the features such as test accuracy is low, result in cannot simply, facilitate and measure accurately in centrifugal load effect
The infiltration coefficient of lower saturated soft soil.
Traditional concentrator bowl mostly utilizes centrifugal acceleration to separate two kinds of different materials, it is considered to different elemental analysis.But do not examine
Consider and design the Seepage problems that concentrator bowl simulates saturated soft soil.
Existing laboratory apparatus is often difficult to infiltration coefficient that is convenient and that simulate saturated soft soil under centrifugal load effect accurately.
Content of the invention
It is an object of the invention to provide the centrifugal seepage flow cylinder that a kind of saturated soft soil infiltration coefficient of measurement under the action of the centrifugal is used.Technical scheme is as follows:
A kind of saturated soft soil centrifuges seepage flow cylinder, is used for measuring saturated soft soil infiltration coefficient under centrifugal action, including, electric rotating machine 60 and glass scales
Rotating cylinder 66.Glass scales rotating cylinder 66 includes with graduated barrel, coaxial big hollow cylinder permeable stone 20 and little hollow cylinder permeable stone 8,
Its material is pervious concrete；For stretching out the machine shaft 4 bottom cylinder in the middle part of it；The inwall of big hollow cylinder permeable stone 20 and little hollow cylinder are permeable
Form soil sample groove 9 between the outer wall of stone 8, post filter paper 6 at soil sample groove 9 inwall, and be placed with saturated soil sample；Little hollow cylinder permeable stone 8 with
Being formed with cavity 21 between machine shaft 4, cavity 21 is for externally to wherein injecting water.
The centrifugal seepage flow cylinder of the present invention, is the important component part of a kind of saturated soft soil vibration centrifugal seepage instrument.
Brief description
Fig. 1 is saturated soft soil vibration centrifugal seepage instrument shaking platform connection figure；
Fig. 2 is that saturated soft soil vibration centrifugal seepage instrument first, second vibrates tension and compression Loading Control schematic diagram；
Fig. 3 is saturated soft soil vibration centrifugal seepage instrument seepage flow connection figure
Fig. 4 is saturated soft soil vibration centrifugal seepage calculation schematic diagram；
1st, drive rod in figure；2nd, the first spring；3rd, collecting-tank；4th, machine shaft；5th, relief valve；6th, filter paper；8th, little hollow cylinder is saturating
Water stone；9th, soil sample groove；10th, tank；11st, piston motor；12nd, water pipe；17th, rotary electromechanical switches；18th, shaking platform；20th, big
Hollow cylinder permeable stone；21st, cavity；22nd, the second spring；23rd, support；24th, valve is regulated；25th, frequency converter；27th, the first rigid rod；32、
Second rigid rod；35th, first piston；36th, first piston cylinder；37th, the second piston cylinder；38th, the second piston；39th, steel column；40th, first is single
To valve；41st, the second check valve；42nd, sink box；60th, electric rotating machine；61st, rotary barrel base；64th, glass scales cylinder；66th, glass
Scale rotating cylinder.
Detailed description of the invention
For further appreciating that content of the invention, feature and effect of the present invention, in conjunction with the application scenarios of the present invention, and accompanying drawing is coordinated to be described in detail.
The present invention is a part of saturated soft soil vibration centrifugal seepage instrument.Whole saturated soft soil Centrifugal vibration seepage instrument includes shaking platform 18,
Saturated soft soil centrifuges seepage flow cylinder, centrifuges, to saturated soft soil, the water filling part that seepage flow cylinder injects water.Saturated soft soil centrifuges seepage flow cylinder and includes that glass scales rotates
Cylinder 66 and electric rotating machine 60.
In FIG, the side of shaking platform 18 is connected with support 23 by horizontal spring 2, and opposite side is added with first by the first rigid rod 27
Carry the fixing connection of steel column 39 of console 19, horizontal direction vibration is done in the first Loading Control platform 19 control；The bottom of shaking platform 18 is by erecting
Straight spring 22 is connected with support, and the middle part of shaking platform 18 is connected by the second rigid rod 32 is fixing with the steel column 39 of the second Loading Control platform 43,
Vertical direction vibration is done in second Loading Control platform 43 control；Shaking platform 18 is fixed with electric rotating machine 60,
In fig. 2, the structure of two Loading Control platforms is identical, including drive rod 1, frequency converter 25, piston motor 11, first piston cylinder 36,
First piston 35, the first check valve 40, sink box 42, the second check valve 41, the second piston cylinder 37, the second piston 38, steel column 39, regulation
Valve 24.Operation principle: open alternating current steady voltage plug, by main controller controls frequency converter 25, thus change the rotary speed of piston motor 11,
The drive rod 1 being connected with piston motor 11 drives the reciprocating motion of first piston 35 in first piston cylinder 36；When first piston 35 upwards moves
When, and under pressure, the water in sink box 42 is upwards moved by the first check valve 40 in the first pipeline, enters into first piston cylinder 36；
When first piston 35 moves downward, the water in first piston cylinder 36 enters into the second piston cylinder 37 by the second check valve 41 in the second pipeline,
And promote the second piston 38, and steel column 39 is driven upwards to move.When the water in first piston cylinder 36 is all pressed into the second piston cylinder 37, logical
Cross main controller controls regulation valve 24 beginning degree, control the water consumption of water release in the second piston cylinder 37, reach the control to steel column 39, make steel
Post 39 moves downward according to certain speed；Displacement transducer is connected with steel column 39, when, in steel column 39 motion process, displacement transducer is by steel column
39 reciprocating motion signals are input in computer.In a computer, can observe whether steel column 39 enters according to sinusoidal wave, rectangular wave and triangular wave
Row motion.The structure of two Loading Control platforms is identical, and steel column 39 is right with shaking platform 18 by the first rigid rod 27 and the second rigid rod 32 respectively
Side and beneath rigidly connected, thus realize that horizontally and vertically tension and compression are vibrated.
In figure 3, glass scales rotating cylinder 66 includes with graduated barrel, coaxial big hollow cylinder permeable stone 20 and little hollow cylinder permeable
Stone 8, its material is pervious concrete；For stretching out the machine shaft 4 bottom cylinder in the middle part of glass scales rotating cylinder 66；At big hollow cylinder permeable stone 20
And be placed with saturated soil sample between little hollow cylinder permeable stone 8, and stick filter paper 6 at the internal diameter and external diameter surface of soil sample.
In figure 3, water filling part mainly includes tank 10 and glass scales cylinder 64.Between little hollow cylinder permeable stone 8 and machine shaft 4
Cavity 21 be connected with glass scales cylinder 64 by water pipe the 12nd, tank 10, the position of glass scales cylinder 64 higher than glass scales rotating cylinder 66,
The water in glass scales cylinder 64 is made to flow into glass rotating scale cylinder 66 smoothly；Machine shaft 4 is driven rotary glass to carve by the driving of electric rotating machine 60
The soil sample of the soil sample groove 9 in degree rotating cylinder 66 does centrifugal motion.
In the diagram, saturated soft soil vibration centrifugal seepage instrument infiltration coefficient of the present invention calculates, and obtains following two public affairs according to collecting-tank water yield and time
Formula, one: only open Loading Control platform, close motor Rotation Controllers, have
Its two, open motor Rotation Controllers, close or open Loading Control platform, have
Wherein a=w2R=Nrg
Δ Q water yield (L)；
Δ t Seepage flow time；
λ weak soil seepage flow correction factor；
The angular speed that w electric rotating machine 60 rotates；
G acceleration of gravity；
riThe center line of machine shaft 4 is to the distance of little hollow cylinder permeable stone 8；
r0The center line of machine shaft 4 is to the distance of big hollow cylinder permeable stone 20；
R is the distance of the center line of machine shaft 4 to glass scales rotating cylinder 66；
NrLikeness coefficient；
PwBy the pressure differential after soil sample.Pw=ρwgΔh；
ρwThe density of water；
The Δ h loss of flood peak, i.e. glass scales cylinder numerical difference Δ h=h when on-test and off-test1-h2；
Now as a example by the test simulating saturated soft soil infiltration coefficient under dynamic load and centrifugal coupling, the specifically used process of the present invention is described, specifically
Implement step as follows:
(1), after pilot system assembles according to accompanying drawing and finishes, first will put into the filter paper 6 of dipped water inside soil sample groove 9, and check that little hollow cylinder is saturating
Whether water stone 8 and big hollow cylinder permeable stone 20 block, and then again saturated soft soil sample are put into soil sample groove 9；
(2) glass scales cylinder 64 is placed on the position higher than rotating scale cylinder 66, cavity 21 is filled water, read the number of glass scales cylinder 64
Value h1；
(3) open shake table 18, selected the waveform of corresponding frequencies by master console, and by the first Loading Control platform control horizontal direction
Vibration or the control vertical displacement of the second Loading Control platform, the motion conditions of the steel column 39 according to computer acquisition regulates two Loading Control platform vibrations
Frequency.
(4) open rotary electromechanical switches 17, determine rotary speed ω by electric rotating machine；
(5) determine infiltration time Δ t, and record glass scales rotating cylinder 66 water yield Δ Q value, again read off the numerical value h of glass scales2；
(6) pass through above-mentioned formula calculation permeability coefficient, terminate test.
The saturated soft soil using the present invention centrifuges the seepage instrument of seepage flow cylinder, has the advantage that the 1st, with saturated soft soil as research object, can be true
The seepage characteristic of weak soil under simulation centrifugal load effect, the permeability coefficient calculating is more authentic and valid；2nd, pass through water yield parameter, Δ Q and when
Between Δ t and two number of degrees h of glass scales cylinder1、h2, just can determine that the loss of flood peak and infiltration coefficient, parameter is few, convenient；3rd, by the present invention from
Heart seepage flow cylinder and shake table are combined together, it can be considered that vibration and the impact on saturated soft soil Penetration Signature for the centrifugal coupling effect, simple.Always
It, structure setting is simple, convenient, testing expenses are low；Measure saturated soft soil infiltration coefficient more accurate, be closer to truth.
Although being described above in conjunction with a certain embodiment to the present invention for the accompanying drawing, but the present invention being not limited to above-mentioned specific embodiment party
Formula, above-mentioned detailed description of the invention is only schematically, is not circumscribed, those of ordinary skill in the art under the enlightenment of the present invention,
In the case of without departing from present inventive concept and scope of the claimed protection, can be to make a lot of form, these belong to the protection model of the present invention
Within enclosing.
Claims (1)
1. saturated soft soil centrifuges a seepage flow cylinder, is used for measuring saturated soft soil infiltration coefficient under centrifugal action, including, electric rotating machine (60) and glass
Glass scale rotating cylinder (66), glass scales rotating cylinder (66) includes with graduated barrel, coaxial big hollow cylinder permeable stone (20) and little
Hollow cylinder permeable stone (8), its material is pervious concrete；For stretching out the machine shaft ((4)) bottom cylinder in the middle part of it；Big hollow cylinder permeable stone
(20) form soil sample groove (9) between inwall and the outer wall of little hollow cylinder permeable stone (8), post filter paper (6) at soil sample groove (9) inwall,
And it is placed with saturated soil sample；Be formed with cavity (21) between little hollow cylinder permeable stone (8) and machine shaft (4), cavity (21) for from
Outside injects water wherein.
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| CN201610526219.4A CN105987869B (en) | 2016-07-06 | 2016-07-06 | A kind of saturated soft soil centrifugation seepage flow cylinder |
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| CN201610526219.4A CN105987869B (en) | 2016-07-06 | 2016-07-06 | A kind of saturated soft soil centrifugation seepage flow cylinder |
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| CN105987869B CN105987869B (en) | 2019-05-07 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109100280A (en) * | 2018-09-04 | 2018-12-28 | 东华理工大学 | A kind of multi-functional soil nature test macro |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109100280A (en) * | 2018-09-04 | 2018-12-28 | 东华理工大学 | A kind of multi-functional soil nature test macro |
| CN109100280B (en) * | 2018-09-04 | 2021-01-29 | 东华理工大学 | Multifunctional soil property testing system |
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