CN106680459A - Experimental device for simulating liquefaction of tailings - Google Patents

Abstract

The invention relates to an experimental device for simulating tailings liquefaction, which belongs to the field of mine geotechnical engineering. The experimental device includes rubber pads, caps, limit devices, sliders, guide rails, vibrating table tops, model boxes, sponges, rigid fixed couplings, servo hydraulic machines, frequency regulators, amplitude regulators, acceleration sensors and pore pressure sensor. The rubber pad is placed at the bottom of the bearing platform to slow down the vibration. The side wall of the model box is made of transparent plexiglass, and the inner wall of the plexiglass is pasted with sponge to absorb the lateral boundary reflection wave. , the limit device is set on the platform, the guide rail is fixed between the limit devices, the slider is fixed on the bottom of the vibrating table, the slider slides horizontally on the guide rail, and the acceleration sensor is set on the vibrating table to record the input vibration. Inside the model box Acceleration sensors and pore pressure sensors are also buried at different depths. The invention can repeatedly reproduce the liquefaction process of the tailings and record the change law of the ultra-static pore water pressure and the acceleration of the tailings at different depths in the liquefaction process.

Description

An experimental device for simulating tailings liquefaction

technical field

The invention relates to the field of mine geotechnical engineering, in particular to an experimental device for simulating tailings liquefaction, which is mainly used to simulate the vibration liquefaction process of tailings indoors.

Background technique

Tailings is the material discharged after the ore is ground and useful components are selected. The tailings dam is a dam built to store the tailings in an orderly manner. my country is an earthquake-prone country with a wide distribution of earthquake areas and frequent earthquakes. However, the tailings have finer particles, larger specific gravity, and weak hydrophilicity. The saturated loose tailings have a very sensitive unstable structure and low strength under dynamic load conditions. , the change range of the dynamic shear stress ratio is small, and the liquefaction phenomenon is more likely to occur during an earthquake, resulting in slippery damage to the tailings dam, resulting in greater casualties and environmental disasters. The total stress borne by the tailings includes two parts: pore water pressure and effective stress. The process of tailings liquefaction is a process in which the pore water pressure in the tailings increases continuously and the effective stress decreases continuously. In view of the seriousness of tailings dam liquefaction hazards, it is necessary to deeply explore the liquefaction mechanism and destruction process of tailings under vibration, and take measures to reduce the possibility of liquefaction. The basic principle of the simulation experiment is to use the model experiment to simulate the actual working conditions of the prototype structure according to the laws of physical phenomena, and then deduce some characteristics of the prototype structure according to the results of the model test. The simulation experiment is an important means to study the characteristics of the prototype structure It has been widely used in various fields. The invention is an experimental device for simulating tailings liquefaction, which can reproduce the vibration liquefaction process of tailings and record the changes of ultra-static pore water pressure and vibration acceleration during the liquefaction process.

Contents of the invention

As a simulation experiment device, the present invention aims to obtain the regularity of the acceleration response of the tailings dam, the accumulation and dissipation of excess static pore pressure, and the characteristics of soil settlement under earthquake action. In order to reveal the vibration liquefaction mechanism of the tailings dam, a Anti-liquefaction measures provide experimental basis.

The purpose of the present invention can be achieved through the following technical solutions:

An experimental device for simulating tailings liquefaction, including rubber pads, caps, limit devices, sliders, guide rails, vibrating table tops, model boxes, sponges, rigid fixed couplings, servo hydraulic machines, frequency regulators, and amplitude adjustments sensors, accelerometers and pore pressure sensors.

The rubber pad is placed at the lower part of the cap, and the cap and the rubber pad are fixed on the concrete ground by expansion screws, so as to reduce the impact of the vibration of the cap on the ground.

The side wall material of the model box is transparent plexiglass, and the plexiglass is bonded by superglue. The inner wall of the model box is pasted with epoxy resin to absorb the lateral boundary reflection wave, and the bottom of the model box is pasted with epoxy resin. Geotextile To increase the friction with the tailings in the box.

The table top of the vibrating table is made of steel plate, and the boundary of the steel plate exceeds the bottom of the model box by 100 mm. The table top of the vibrating table is connected with the servo hydraulic machine through a rigid fixed coupling.

The surface of the vibrating table is at the same level as the rigid fixed coupling and the servo hydraulic machine, so as to ensure that no bending moment is generated by the input vibration force.

There are two guide rails in total, and the guide rails are fixed with the limit device, and the two guide rails are on the same horizontal plane and are parallel to each other.

The limiting devices are four steel blocks in total, and the steel blocks and the platform are fixed by bolts.

The slider is a steel block, and the slider is fixed on the lower part of the vibrating table by bolts. The bottom of the slider is in the shape of a groove, and the surface of the groove is coated with lubricant and contacts with the guide rail.

One of the acceleration sensors is fixed on the vibrating table to record the input vibration acceleration, and the other acceleration sensors are embedded in the model box at different depths.

The pore pressure sensors are buried at different depths on the same vertical surface in the model box.

The servo hydraulic machine is fixed on the bearing platform by bolts, and the frequency regulator and the amplitude regulator are connected to the servo hydraulic machine through wires to control the vibration frequency and amplitude of the servo hydraulic machine respectively.

Description of drawings

Figure 1 is a schematic cross-sectional view of the present invention.

Figure 2 is a schematic top view of the present invention.

In the figure: 1 rubber pad, 2 bearing platform, 3 limit device, 4 slider, 5 guide rail, 6 vibrating table top, 7 model box, 8 sponge, 9 rigid fixed coupling, 10 servo hydraulic machine, 11 frequency regulator , 12 amplitude regulators, 13 acceleration sensors, 14 hole pressure sensors.

detailed description

The present invention will be further described below in conjunction with accompanying drawing and embodiment, but should not be interpreted as that the scope of above-mentioned theme of the present invention is limited to following embodiment, under the situation that does not depart from above-mentioned technical thought of the present invention, according to common technical knowledge and customary practice in this field Means, making various replacements and changes shall be included in the protection scope of the present invention.

As shown in Figure 1 and Figure 2, an experimental device for simulating tailings liquefaction, including 1 rubber pad, 2 caps, 3 limit devices, 4 sliders, 5 guide rails, 6 vibration table tops, 7 model boxes, and 8 sponges , 9 rigid fixed coupling, 10 servo hydraulic press, 11 frequency regulator, 12 amplitude regulator, 13 acceleration sensor and 14 hole pressure sensor.

The model box 7 is a container with an open upper end, the side wall of the model box 7 is transparent plexiglass, and the plexiglass is bonded by superglue. The vibrating table top 6 is a steel plate, and the boundary of the steel plate exceeds the bottom of the model box 7 by 100 mm. Holes are punched between the model box 7 and the vibrating table top 6 and fixed together with screws, and the gaps are sealed with waterproof sealant. Paste a 50mm thick sponge 8 with epoxy resin on the inner wall of the model box 7 to absorb lateral boundary reflection waves, and paste a geotextile with epoxy resin at the bottom of the model box 7 to increase the friction between the tailings and the bottom of the model box 7 .

The rubber pad 1 is located at the bottom of the platform 2, and the platform 2 and the rubber pad 1 are fixed on the concrete ground by expansion screws to achieve the purpose of slowing down the vibration impact.

First weld the two ends of the guide rails 5 to the same parts of the limiter 3 respectively, and then fix the limiter 3 on the platform of the bearing platform 2 by bolts to ensure that the two guide rails 5 are coplanar and parallel to each other.

The slide block 4 is a steel block, and the steel block is fixed on the bottom of the vibrating table 6 by bolts. The bottom of the slide block 4 is in the shape of a groove, and the lubricant is applied on the surface of the groove and placed on the guide rail 5, so that the slide block 4 It can slide back and forth horizontally on the guide rail 5.

When the servo hydraulic machine 10 is installed, its base is fixed on the platform of the bearing platform 2 with bolts, and the power output shaft of the servo hydraulic machine 10 is on the same level as the vibration table table 6, so as to ensure that the vibration is along the horizontal direction. The servo hydraulic machine 10 is connected with the vibrating table top 6 with a rigid fixed shaft coupling 9 . The frequency regulator 11 and the amplitude regulator 12 are connected to the servo hydraulic machine 10 through wires, and control the vibration frequency and amplitude of the servo hydraulic machine 10 respectively.

One of the acceleration sensors 13 is fixed on the vibrating table top 6 to record the input vibration acceleration, and the other acceleration sensors 13 are embedded in the model box 7 at different depths. The pore pressure sensors 14 are embedded at different depths on the same vertical plane in the model box 7 .

Before the experiment, it is necessary to prepare saturated tailings in the model box 7. First, inject a certain amount of pure water into the model box, and then sprinkle the tailings evenly and freely from the top of the model box 7. If the surface of the tailings is uneven, promptly use a scraper. The plate is used to level the surface of the tailings layer, and each operation controls the water surface to be about 100mm above the tailings surface. After the sample preparation is completed, it is left to stand for 24 hours before vibrating.

Claims (8)

1. it is a kind of to simulate the liquefied experimental provision of mine tailing, it is characterised in that including rubber blanket, cushion cap, stopping means, sliding block is led Rail, vibration table surface, model casing, sponge rigidly fixes shaft coupling, servo hydraulic machine, frequency regulator, amplitude modulator, plus Velocity sensor and sensor for pore water pressure；Rubber blanket is placed in cushion cap bottom, and model casing side-wall material is transparent organic glass, organic glass Bonded by seccotine between glass, model chamber interior wall pastes sponge to absorb lateral boundaries back wave, and vibration table surface is by firm Property closed coupling be coupled with servo hydraulic machine, stopping means is provided with cushion cap, guide rail is fixed between stopping means, vibrate Platform table top bottom is fixed with sliding block, and sliding block level on guide rail is slided, and an acceleration transducer, mould are fixed on vibration table surface Also acceleration transducer and sensor for pore water pressure are buried in molding box at different depth.

2. the one kind described in claim 1 simulates the liquefied experimental provision of mine tailing, it is characterised in that the rubber blanket cushion caps bottom Portion, mattess is fixed on by setscrew by cushion cap and rubber blanket.

3. one kind according to claim 1 simulates the liquefied experimental provision of mine tailing, it is characterised in that model casing side wall Inner side is pasted with sponge, and model casing bottom is pasted with geotextiles, and alite paste is epoxy resin.

4. a kind of simulation liquefied experimental provision of mine tailing according to claim 1, it is characterised in that the guide rail totally two Bar, two guide rails are in same level and are parallel to each other.

5. one kind according to claim 1 simulates the liquefied experimental provision of mine tailing, it is characterised in that the vibration table surface Be steel plate, and vibration table surface exceeds model casing bottom 100mm, vibration table surface with rigidly fix shaft coupling, servo hydraulic machine In same level.

6. one kind according to claim 1 simulates the liquefied experimental provision of mine tailing, it is characterised in that the sliding block is steel Block, sliding block is bolted on vibration table surface bottom, and sliding block bottom is groove shapes, groove and guide rail contact.

7. a kind of simulation liquefied experimental provision of mine tailing according to claim 1, it is characterised in that the stopping means is Bloom, bloom is fixed with cushion cap and track simultaneously.

8. one kind according to claim 1 simulates the liquefied experimental provision of mine tailing, it is characterised in that the acceleration sensing In device, there is one to be fixed on vibration table surface, remaining acceleration transducer is embedded in different depth in model casing.