CN205808884U - A kind of saturated soft soil is centrifuged seepage flow cylinder - Google Patents

Abstract

This utility model relates to a kind of saturated soft soil and is centrifuged seepage flow cylinder, 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 that its material is pervious concrete with graduated barrel, coaxial big hollow cylinder permeable stone (20) and little hollow cylinder permeable stone (8)；For to stretch out the machine shaft ((4)) bottom cylinder in the middle part of it；Form soil sample groove (9) between inwall and the outer wall of little hollow cylinder permeable stone (8) of big hollow cylinder permeable stone (20), post filter paper (6) at soil sample groove (9) inwall, and be placed with saturated soil sample；Being formed with cavity (21) between little hollow cylinder permeable stone (8) and machine shaft (4), cavity (21) is for externally to wherein injecting water.This utility model can more precisely simulate weak soil seepage consolidation characteristic under dynamic loading.

Description

A kind of saturated soft soil is centrifuged seepage flow cylinder

Technical field

This utility model relates to a kind of saturated soft soil and is centrifuged seepage flow cylinder, particularly relates to one and measures saturated under the action of the centrifugal The small-sized centrifugal seepage flow cylinder of weak soil infiltration coefficient.

Background technology

Soil body penetration characteristic is the importance of Characteristics of Geotechnical Engineering research, and tolerance soil body penetration characteristic index is infiltration system Number, the experimental provision of existing measurement infiltration coefficient mainly has constant head darcy flow instrument and varying head darcy flow instrument, this experiment Instrument has the advantages such as accuracy height, technology maturation to sand gas permeability measurement.

But saturated soft soil has, and moisture content is high, compressibility is high, void ratio is high, bearing capacity is low, permeate little " three-hypers two is low " Characteristic, its seepage flow often shows non-darcy flow characteristic.Apply existing constant head darcy flow instrument and varying head darcy Weak soil gas permeability measurement will be caused result deviation engineering actual by seepage instrument, it is impossible to instructs geotechnical engineering investigation, it is more likely that Huge loss is brought to geotechnical engineering design, construction.

Along with the continuous quickening of city process, the traffic engineering such as subway, railway, highway quickly grows, China built and Occupy first place in the world in the High Speed Rail Projects position built.Geotechnical engineering investigation more pays close attention to different frequency dynamic load to Technical Characteristics of Mild Clay With under pollutant migration problem in soil, especially dynamic load and centrifugal coupling in weak soil seepage characteristic problem, the most still Use existing constant head darcy flow instrument and varying head darcy flow instrument to weak soil gas permeability measurement, with engineering practice not How symbol, more can not migrate in soil by simulating pollution thing, lack corresponding experimental provision.

So people start increasingly to pay close attention to the research to weak soil seepage characteristic, and theoretical research is accumulated with engineering experience Achievement in research be applied in engineering practice.

Centrifugal machine model trial by internationally recognized for be research the scientific experimentation most effective, state-of-the-art of rock-soil dynamics problem Platform.First Columbia Univ USA in 1931 develops First radius in the world is the geotechnical centrifuge of 0.25m, 19 generation Recording the beginning of the seventies, geotechnical centrifuge in succession develops in American and Britain, the Soviet Union, method, Deng state, develops turntable type centrifuge, basket-hanging Centrifuge and drum centrifuge, China started to pay attention to power Centrifuge Techniques the eighties in 19th century, and nineteen eighty-two is by the Changjiang river science Academy is called for short, and maximum centrifugal acceleration reaches 300g, capacity 150g-t effective radius 3m.Up to now, China has more than 20 Desk centrifuge.Test model can reflect condition and the behavior of prototype truely and accurately, needs to meet several between model and prototype What similar, kinematic similitude and three primary condition of dynamic similitude law, i.e. corresponding between similarity criterion and the parameter of each parameter Rapport.

Although traditional turntable type centrifuge, suspended centrifugal and drum centrifuge can reach the effect of centrifugal seepage flow, But due to operation complexity, the scale of construction of seepage instrument is big, and testing expenses are high, the features such as test accuracy is low, resulting in cannot simply, conveniently Measure the infiltration coefficient of saturated soft soil under centrifugal load effect accurately.

Traditional concentrator bowl mostly utilizes centrifugal acceleration to be separated by two kinds of different materials, it is considered to different materials becomes Analyze.But do not account for and design concentrator bowl to simulate the Seepage problems of saturated soft soil.

Existing experimental apparatus is often difficult to convenient and simulates the infiltration of saturated soft soil under centrifugal load effect accurately Coefficient.

Utility model content

The purpose of this utility model be to provide a kind of under the action of the centrifugal measure saturated soft soil infiltration coefficient used from Heart seepage flow cylinder.Technical scheme is as follows:

A kind of saturated soft soil is centrifuged 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 saturating Water stone 20 and little hollow cylinder permeable stone 8, its material is pervious concrete；For to stretch out the machine shaft 4 bottom cylinder in the middle part of it；Greatly Soil sample groove 9 is formed, at soil sample groove 9 inwall between inwall and the outer wall of little hollow cylinder permeable stone 8 of hollow cylinder permeable stone 20 Post filter paper 6, and be placed with saturated soil sample；It is formed with cavity 21, cavity between little hollow cylinder permeable stone 8 and machine shaft 4 21 for externally to wherein injecting water.

Centrifugal seepage flow cylinder of the present utility model, is the important component part of a kind of saturated soft soil vibration centrifugal seepage instrument.

Accompanying drawing explanation

Fig. 1 is saturated soft soil vibration centrifugal seepage instrument vibration platen 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；

In figure 1, drive rod；2, the first spring；3, collecting-tank；4, machine shaft；5, relief valve；6, filter paper；8, little hollow Cylinder permeable stone；9, soil sample groove；10, tank；11, piston motor；12, water pipe；17, rotary electromechanical switches；18, vibration is flat Platform；20, big hollow cylinder permeable stone；21, cavity；22, the second spring；23, support；24, regulation valve；25, converter；27, One rigid rod；32, the second rigid rod；35, first piston；36, first piston cylinder；37, the second piston cylinder；38, the second piston； 39, steel column；40, the first check valve；41, the second check valve；42, sink box；60, electric rotating machine；61, rotary barrel base；64, glass Glass dial drum；66, glass scales rotating cylinder.

Detailed description of the invention

For further appreciating that utility model content of the present utility model, feature and effect, answer in conjunction with of the present utility model By scene, and accompanying drawing is coordinated to be described in detail.

This utility model is an ingredient of saturated soft soil vibration centrifugal seepage instrument.Whole saturated soft soil Centrifugal vibration Seepage instrument includes vibration platen 18, and saturated soft soil is centrifuged seepage flow cylinder, is centrifuged seepage flow cylinder to saturated soft soil and injects the water filling part of water. Saturated soft soil is centrifuged seepage flow cylinder and includes glass scales rotating cylinder 66 and electric rotating machine 60.

In FIG, the side of vibration platen 18 is connected with support 23 by horizontal spring 2, and opposite side passes through the first rigidity Bar 27 is fixing with the steel column 39 of the first Loading Control platform 19 to be connected, the first Loading Control platform 19 control to do horizontal direction vibration； The bottom of vibration platen 18 is connected with support by uprighting spring 22, and the second rigid rod 32 and the is passed through at the middle part of vibration platen 18 The steel column 39 of two Loading Control platforms 43 is fixing to be connected, the second Loading Control platform 43 control to do vertical direction vibration；Flat in vibration Electric rotating machine 60 it is fixed with on platform 18,

In fig. 2, the structure of two Loading Control platforms is identical, including drive rod 1, and 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, regulate valve 24.Operation principle: open alternating current steady voltage plug, by main controller controls converter 25, thus change Becoming the rotary speed of piston motor 11, the drive rod 1 being connected with piston motor 11 is to drive first piston in first piston cylinder 36 The reciprocating motion of 35；When first piston 35 moves upward, and under pressure, the water in sink box 42 passes through the first pipeline In the first check valve 40 move upward, enter into first piston cylinder 36；When first piston 35 moves downward, first piston cylinder 36 In water enter into the second piston cylinder 37 by the second check valve 41 in the second pipeline, and promote the second piston 38, and drive Steel column 39 moves upward.When the water in first piston cylinder 36 is all pressed into the second piston cylinder 37, pass through main controller controls Regulation valve 24 beginning degree, controls the water consumption of the release of water in the second piston cylinder 37, reaches the control to steel column 39, make steel column 39 by Move downward according to certain speed；Displacement transducer is connected with steel column 39, when, in steel column 39 motor process, displacement transducer is by steel Post 39 moves back and forth signal and is input in computer.In a computer, steel column 39 can be observed whether according to sinusoidal wave, rectangular wave Move with triangular wave.The structure of two Loading Control platforms is identical, and steel column 39 is respectively by the first rigid rod 27 and second On the right side of rigid rod 32 and vibration platen 18 and beneath rigidly connected, thus realize horizontally and vertically tension and compression vibration.

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；Turn for stretching out the motor bottom cylinder in the middle part of glass scales rotating cylinder 66 Axle 4；Saturated soil sample it is placed with between big hollow cylinder permeable stone 20 and little hollow cylinder permeable stone 8, and at the internal diameter of soil sample With stick filter paper 6 at external diameter surface.

In figure 3, water filling part mainly includes tank 10 and glass scales cylinder 64.Little hollow cylinder permeable stone 8 with Cavity 21 between machine shaft 4 is connected with glass scales cylinder 64 by water pipe 12, tank 10, the position of glass scales cylinder 64 Higher than glass scales rotating cylinder 66 so that the water in glass scales cylinder 64 flows into glass rotating scale cylinder 66 smoothly；Machine shaft 4 Centrifugal motion is done by the soil sample driving the soil sample groove 9 in rotary glass scale rotating cylinder 66 that drives of electric rotating machine 60.

In the diagram, this utility model saturated soft soil vibration centrifugal seepage instrument infiltration coefficient calculates, according to collecting-tank water yield Following two formula are obtained, one: only open Loading Control platform, close motor Rotation Controllers, have with the time

$k=\mathrm{\λ}\frac{\frac{\mathrm{\Δ}Q}{\mathrm{\Δ}t}}{\frac{-\frac{w^2}{2g}{(r_0-r_i)}^2-\frac{P_w}{{\mathrm{\ρ}}_{w}g}}{r_0-r_i}}$

Its two, open motor Rotation Controllers, close or open Loading Control platform, have

$k=\mathrm{\λ}\frac{\frac{\mathrm{\Δ}Q}{\mathrm{\Δ}t}}{\frac{-\frac{w^2}{2N_{r}g}{(r_0-r_i)}^2-\frac{P_w}{{\mathrm{\ρ}}_{w}g}}{r_0-r_i}}$

Wherein a=w²R=N_rg

Δ Q water yield (L)；

Δ t Seepage flow time；

λ weak soil seepage flow correction factor；

The angular velocity that w electric rotating machine 60 rotates；

G acceleration of gravity；

r_iThe centrage of machine shaft 4 is to the distance of little hollow cylinder permeable stone 8；

r₀The centrage of machine shaft 4 is to the distance of big hollow cylinder permeable stone 20；

R is the centrage distance to glass scales rotating cylinder 66 of machine shaft 4；

N_rLikeness coefficient；

P_wBy the pressure differential after soil sample.P_w=ρ_wgΔh；

ρ_wThe 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 under simulation dynamic load and centrifugal coupling as a example by the test of saturated soft soil infiltration coefficient, illustrate that this practicality is new The specifically used process of type, is embodied as step as follows:

(1), after pilot system assembles according to accompanying drawing, first will put into the filter paper 6 of dipped water inside soil sample groove 9, and examine Look into little hollow cylinder permeable stone 8 and whether big hollow cylinder permeable stone 20 blocks, the most again saturated soft soil sample is 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 glass and carve The numerical value h of degree cylinder 64₁；

(3) open vibration table 18, selected the waveform of corresponding frequencies by master console, and by the first Loading Control platform The vibration or the second Loading Control platform that control horizontal direction control vertical displacement, according to the motion of the steel column 39 of computer acquisition Situation two Loading Control platform frequency of vibration of regulation.

(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 glass scales Numerical value h₂；

(6) by above-mentioned formula calculation permeability coefficient, test is terminated.

Use saturated soft soil of the present utility model to be centrifuged the seepage instrument of seepage flow cylinder, have the advantage that 1, with saturated soft soil For object of study, it is possible to the seepage characteristic of weak soil under true simulation centrifugal load effect, the permeability coefficient calculated is trueer Real effective；2, by water yield parameter, Δ Q and time Δ t and two number of degrees h of glass scales cylinder₁、h₂, just can determine that head damages Becoming estranged infiltration coefficient, parameter is few, convenient；3, centrifugal seepage flow cylinder of the present utility model and vibration table are combined, it is possible to examine Consider vibration and the impact on saturated soft soil Penetration Signature of the centrifugal coupling effect, simple.In a word, structure arrange simple, convenient, Testing expenses are low；Measure saturated soft soil infiltration coefficient more accurate, be closer to truth.

Although a certain embodiment of the present utility model being described above in conjunction with accompanying drawing, but this utility model being not Being limited to above-mentioned detailed description of the invention, above-mentioned detailed description of the invention is only schematically, is not circumscribed, this The those of ordinary skill in field is under enlightenment of the present utility model, without departing from this utility model objective and claimed Ambit under, it is also possible to make a lot of form, within these belong to protection domain of the present utility model.

Claims (1)

1. saturated soft soil is centrifuged a 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), it is characterised in that glass scales rotating cylinder (66) includes carrying graduated barrel, coaxial Big hollow cylinder permeable stone (20) and little hollow cylinder permeable stone (8), its material is pervious concrete；For stretching out cylinder in the middle part of it The machine shaft (4) of bottom；Shape between inwall and the outer wall of little hollow cylinder permeable stone (8) of big hollow cylinder permeable stone (20) Become soil sample groove (9), 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.