Method for measuring thickness deformation of bentonite blanket test specimens

Abstract

This invention provides a method for measuring the thickness deformation of bentonite waterproof blanket samples. 1) After setting up the first permeable stone, first filter paper, second filter paper, and second permeable stone, place them between the sample base and the sample top cover, then seal them; connect the guide rod to the top cover connector; apply confining pressure and counter-pressure, and zero the dial gauge; 2) After setting up the first permeable stone, first filter paper, geotextile, second filter paper, and second permeable stone, place them between the sample base and the sample top cover, then seal them; apply confining pressure and counter-pressure, and record the thickness value of the geotextile; 3) Set up the first permeable stone, first filter paper, bentonite waterproof blanket sample, second filter paper, and second permeable stone, place them between the sample base and the sample top cover, then seal them; connect the guide rod to the top cover connector; hydrate and saturate the bentonite waterproof blanket sample, increasing the upstream counter-pressure at the bottom of the sample; 4) Bentonite thickness = total thickness value - geotextile thickness value. This method can measure the thickness change of bentonite samples in real time.

Description

Technical Field

[0001] This invention relates to the field of sample measurement technology, and in particular to a method for measuring the thickness deformation of bentonite waterproof blanket samples. Background Technology

[0002] Bentonite waterproofing blankets utilize the water-swelling property of bentonite, and are used as impermeable linings in landfills. They have also been widely adopted in other civil engineering seepage control applications in many countries. The bentonite used in these blankets, also known as bentonite rock or bentonite ore, is formed from volcanic ash deposited during the Cretaceous period approximately 100 million years ago. It possesses several unique properties, including swelling, binding, and adsorption. When bentonite comes into contact with water, it hydrates and expands, forming a water-impermeable gel, thus providing natural waterproofing and seepage prevention. Utilizing this property, geotextiles and bentonite are fixed together using a needle-punching method to create bentonite waterproofing blankets. The geotextiles are typically made of polypropylene, with a non-woven upper layer and a woven lower layer. Vertical permeability tests on bentonite waterproofing blankets utilize the water absorption and expansion of bentonite particles after hydration, forming a relatively uniform colloidal system that fills the entire space. Under limited pressure, the expanded bentonite reaches a certain density, and its permeability is tested. The volume change of bentonite after hydration is significant.

[0003] Currently, existing flexible-wall vertical permeameters in China cannot measure the thickness change of the test sample in real time when testing the permeability of bentonite waterproofing blankets. The thickness can only be measured after the permeability test is completed and the sample is removed from the flexible-wall vertical permeameter. The thickness of the sample measured after removal from the flexible-wall vertical permeameter is inaccurate compared to the sample thickness under the constraint of overburden pressure on bentonite hydration and expansion. In addition, the process of cutting and peeling the upper and lower layers of fabric with a blade can easily come into contact with the bentonite, leading to measurement errors and affecting the final calculation of the permeability coefficient. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the technical problem solved by the present invention is to provide a method for measuring the thickness deformation of bentonite waterproof blanket samples that can measure the thickness change of bentonite samples in real time.

[0005] To achieve the above and other related objectives, this invention provides a method for measuring the thickness deformation of bentonite waterproof blanket samples. The method employs a bentonite waterproof blanket sample thickness deformation measuring device, which is installed on a osmotic pressure chamber. The osmotic pressure chamber includes an osmotic pressure cylinder, with a pressure chamber top cover installed at the upper end of the cylinder and a pressure chamber base installed at the lower end. The osmotic pressure cylinder contains a sample base and a sample top cover positioned directly above the sample base, with a testing interval between the sample base and the sample top cover. The sample base is connected to an upstream water inlet pipe, and the sample top cover is connected to a downstream water inlet pipe.

[0006] The top surface of the sample cover is provided with a cover connector, the top surface of the cover connector is provided with a mounting groove, the upper ends of the two parallel sidewalls of the mounting groove are provided with protrusions, the two protrusions are arranged opposite each other and there is a block gap between the two protrusions; the pressure chamber cover is provided with a through hole.

[0007] The bentonite waterproof blanket sample thickness deformation measuring device includes:

[0008] A guide rod, the upper end of which protrudes through the through hole; the lower end of the guide rod is provided with a mounting head, which is inserted into the mounting groove. After the mounting head rotates below the protrusions, the two protrusions prevent the mounting head from disengaging from the mounting groove. The mounting head is connected to the top cover connector.

[0009] An instrument mounting bracket is installed on the top cover of the pressure chamber;

[0010] A dial indicator includes a dial indicator body and a dial indicator rod connected to the dial indicator body. The dial indicator body is mounted on the instrument mounting base, and the lower end of the dial indicator rod contacts the top end of the guide rod.

[0011] A method for measuring the thickness deformation of bentonite waterproof blanket samples includes the following steps:

[0012] 1) Zeroing the dial indicator: After placing the first permeable stone, the first filter paper, the second filter paper, and the second permeable stone in order from top to bottom, place them in the test interval between the sample base and the sample top cover, and then seal them with latex film; connect the mounting head at the lower end of the guide rod to the top cover connector; apply confining pressure and back pressure to the osmotic pressure chamber, and adjust the position of the instrument mounting base in the vertical direction; when the lower end of the dial indicator rod installed on the instrument mounting base contacts the top end of the guide rod, tighten the first fastener to fix the position of the instrument mounting base, zero the dial indicator, and then tighten the second fastener to fix the position of the dial indicator to prevent the dial indicator from sliding;

[0013] 2) Inserting Geotextile: Without changing the position of the dial gauge, remove the permeability pressure chamber; shake off the bentonite from the bentonite waterproof blanket sample, leaving the geotextile in the sample; arrange the first permeable stone, the first filter paper, the geotextile, the second filter paper, and the second permeable stone in order from top to bottom, and place them in the test interval between the sample base and the sample top cover, then seal them with latex film, and connect the mounting head at the lower end of the guide rod to the top cover connector; apply confining pressure and back pressure to the permeability pressure chamber, and record the thickness value of the geotextile with a dial gauge;

[0014] 3) Load the complete bentonite waterproof blanket sample; without changing the position of the dial gauge, remove the osmotic pressure chamber; arrange the first permeable stone, the first filter paper, the bentonite waterproof blanket sample, the second filter paper, and the second permeable stone in order from top to bottom, and place them in the test interval between the sample base and the sample top cover, and then seal them with latex film; connect the mounting head at the lower end of the guide rod to the top cover connector; under confining pressure and back pressure conditions, the bentonite waterproof blanket sample is hydrated and saturated, and then the upstream back pressure at the bottom of the bentonite waterproof blanket sample is increased to form an effective osmotic pressure, and seepage occurs from bottom to top; measure the volume of seeping liquid, the seepage time, and record the head difference between the two ends of the bentonite waterproof blanket sample and the total thickness of the bentonite waterproof blanket sample.

[0015] 4) Calculation: Bentonite thickness = Total thickness - Geotextile thickness.

[0016] Preferably, the distance between the two parallel sidewalls of the mounting groove is the width of the mounting groove;

[0017] The mounting head includes an upper mounting part, a middle mounting part, and a lower mounting part connected sequentially from top to bottom; the width of the middle mounting part and the width of the lower mounting part are both less than the distance between the two protrusions; the length of the middle mounting part is less than the distance between the two protrusions; the length of the lower mounting part is greater than the distance between the two protrusions; the length of the lower mounting part is less than the width of the mounting groove; and the length of the upper mounting part is greater than the distance between the two protrusions.

[0018] Furthermore, the bottom wall of the mounting groove is parallel to the top surface of the top cover connector, and the top surface of the top cover connector is parallel to the horizontal plane; the distance between the bottom surface of the protrusion and the bottom wall of the mounting groove is greater than the vertical height of the lower mounting part.

[0019] Furthermore, the vertical height of the protrusion is less than or equal to the vertical height of the intermediate mounting portion.

[0020] Furthermore, the lower mounting portion has a rectangular cross-section, and the four corners of the bottom of the lower mounting portion are chamfered.

[0021] Preferably, the main body of the watch is connected to the watch stem via a lower sleeve rod; a support rod is provided on the top surface of the top cover connector, and the central axis of the support rod is perpendicular to the horizontal plane.

[0022] The length direction of the instrument mounting base is parallel to the horizontal plane; the two ends of the instrument mounting base in the length direction are the instrument mounting end and the support mounting end, respectively.

[0023] The instrument mounting base has a support mounting through hole, a support adjustment slot, and a support adjustment through hole on its support mounting end; the support adjustment slot extends to the end face of the support mounting end of the instrument mounting base; the central axis of the support mounting through hole is vertically arranged, and both the support mounting through hole and the support adjustment through hole communicate with the support adjustment slot; the central axis of the support mounting through hole is perpendicular to the central axis of the support adjustment through hole; the support mounting through hole allows the support rod to be inserted; a first fastener is connected to the support adjustment through hole, so that the support mounting through hole clamps the support rod;

[0024] The instrument mounting base has an instrument mounting through hole, an instrument adjustment slot, and an instrument adjustment through hole on its instrument mounting end. The instrument adjustment slot extends to the end face of the instrument mounting end of the instrument mounting base. The central axis of the instrument mounting through hole is vertically arranged, and both the instrument mounting through hole and the instrument adjustment through hole are connected to the instrument adjustment slot. The central axis of the instrument adjustment through hole is perpendicular to the central axis of the instrument mounting through hole. The instrument mounting through hole allows the lower sleeve rod to be inserted. A second fastener is connected to the instrument adjustment through hole, so that the instrument mounting through hole clamps the lower sleeve rod.

[0025] As described above, the method for measuring the thickness deformation of bentonite waterproof blanket samples of the present invention has the following beneficial effects:

[0026] 1) In the bentonite waterproof blanket sample thickness deformation measurement method of the present invention, after the mounting head of the lower end of the guide rod rotates in the mounting groove of the top cover connector, the mounting head of the guide rod and the top cover connector form an interlocking connection, and the guide rod is connected to the sample top cover; the connection between the mounting head of the guide rod and the top cover connector is convenient and not easy to slip off.

[0027] 2) The bentonite waterproof blanket sample thickness deformation measurement method of the present invention can track the deformation of the bentonite sample thickness while testing the permeability performance of the bentonite waterproof blanket. Under the combined action of confining pressure and counter pressure, the thickness of the bentonite sample in the final saturated, hydrated and consolidated state can be measured, thus obtaining the effective permeability of the bentonite sample. The permeability coefficient of the bentonite waterproof blanket can be accurately calculated based on the thickness of the bentonite sample. The bentonite waterproof blanket sample thickness deformation measurement method of the present invention can test the thickness of the bentonite sample without peeling off the geotextile on the bentonite sample.

[0028] 3) The bentonite waterproof blanket sample thickness deformation measurement method of the present invention can be directly installed on the osmosis pressure chamber of the existing flexible wall vertical permeameter, and only requires a through hole for the guide rod to pass through on the pressure chamber top cover of the osmosis pressure chamber. Attached Figure Description

[0029] Figure 1 The diagram shows the structure of the bentonite waterproof blanket sample thickness deformation measuring device installed on the osmotic pressure chamber, with the bentonite waterproof blanket placed inside the osmotic pressure chamber.

[0030] Figure 2 The diagram shows the structure of the bentonite waterproof blanket sample thickness deformation measuring device after the guide rod and the top cover connector are connected.

[0031] Figure 3 Displayed as Figure 2 A magnified structural diagram of point A in the middle.

[0032] Figure 4 The diagram shown is a side view of the guide rod of the bentonite waterproof blanket sample thickness deformation measuring device in this embodiment.

[0033] Figure 5 Displayed as Figure 4 A magnified structural diagram at point B in the middle.

[0034] Figure 6 This diagram shows a bottom view of the guide rod of the bentonite waterproof blanket sample thickness deformation measuring device in this embodiment.

[0035] Figure 7 This diagram shows a side view of the top cover connector of the bentonite waterproof blanket sample thickness deformation measuring device in this embodiment.

[0036] Figure 8 This diagram shows a top view of the top cover connector of the bentonite waterproof blanket sample thickness deformation measuring device in this embodiment.

[0037] Figure 9 This diagram shows a side view of the instrument mounting base of the bentonite waterproof blanket sample thickness deformation measuring device in this embodiment.

[0038] Figure 10 This diagram shows a top view of the instrument mounting base of the bentonite waterproof blanket sample thickness deformation measuring device in this embodiment.

[0039] Explanation of icon numbers

[0040] 110 Osmotic Pressure Tank

[0041] 120 Pressure Chamber Top Cover

[0042] 121 Through Hole

[0043] 130 Pressure Chamber Base

[0044] 210 Sample base

[0045] 220 Sample Top Cover

[0046] 230 upstream water inlet pipes

[0047] 240 Downstream water inlet pipe of the cover

[0048] 300 Top Cover Connector

[0049] 310 mounting slot

[0050] 311 Tank sidewall

[0051] 312 Tank bottom wall

[0052] 330 bump

[0053] 331 Block Spacing

[0054] 340 mounting column

[0055] 400 guide rod

[0056] 410 mounting head

[0057] 411 Upper Installation Section

[0058] 412 Intermediate mounting section

[0059] 413 Lower Installation Section

[0060] 500 Instrument Mounting Mount

[0061] 510 Support mounting through hole

[0062] 520 Support Adjustment Slot

[0063] 530 Support Adjustment Through Hole

[0064] 540 First Fastener

[0065] 550 gauge mounting through hole

[0066] 560 Gauge Adjustment Slot

[0067] 570 Adjustment Hole

[0068] 580 Second Fastener

[0069] 600 Dial Scale

[0070] 610 Table Body

[0071] 620 dial indicator

[0072] 630 Lower Sleeve

[0073] 700 support rod

[0074] 800 Bentonite Waterproof Blanket

[0075] Width of W1 lower mounting section

[0076] W4 mounting slot width

[0077] Length of K2 intermediate mounting section

[0078] Length of K3 lower mounting section

[0079] Vertical height of the H2 intermediate mounting section

[0080] Vertical height of the lower mounting section H3

[0081] L1 is the distance between the two bumps.

[0082] The distance between the bottom surface of the L2 protrusion and the bottom wall of the mounting groove. Detailed Implementation

[0083] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0084] Please refer to the accompanying drawings. It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and are not intended to limit the scope of the invention. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the disclosed technical content. Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and are not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0085] like Figures 1 to 10As shown, the bentonite waterproof blanket sample thickness deformation measurement method of this embodiment uses a bentonite waterproof blanket sample thickness deformation measurement device, which is installed on a osmotic pressure chamber. The osmotic pressure chamber includes an osmotic pressure cylinder 110, with a pressure chamber top cover 120 installed at the upper end of the osmotic pressure cylinder 110 and a pressure chamber base 130 installed at the lower end of the osmotic pressure cylinder 110. The interior of the osmotic pressure cylinder 110 has a sample base 210 and a sample top cover 220 located directly above the sample base 210, with a test interval between the sample base 210 and the sample top cover 220. The sample base 210 is connected to an upstream water inlet pipe 230 of the base body, and the sample top cover 220 is connected to a downstream water inlet pipe 240 of the cover body.

[0086] The top surface of the sample top cover 220 is provided with a top cover connector 300, and the top surface of the top cover connector 300 is provided with a mounting groove 310. The upper ends of the two parallel groove sidewalls 311 of the mounting groove 310 are each provided with a protrusion 330. The two protrusions 330 are arranged opposite each other, and there is a block gap 331 between the two protrusions 330. The pressure chamber top cover 120 is provided with a through hole 121.

[0087] The bentonite waterproof blanket sample thickness deformation measuring device includes:

[0088] A guide rod 400 has its upper end protruding through the through hole 121; the lower end of the guide rod 400 is provided with a mounting head 410, which is inserted into the mounting groove 310. After the mounting head 410 rotates below the protrusion 330, the two protrusions 330 prevent the mounting head 410 from disengaging from the mounting groove 310. The mounting head 410 is connected to the top cover connector 300.

[0089] An instrument mounting bracket 500 is installed on the pressure chamber top cover 120;

[0090] The dial indicator 600 includes a main body 610 and a stem 620 connected to the main body 610. The main body 610 is mounted on the instrument mounting base 500, and the lower end of the stem 620 contacts the top end of the guide rod 400.

[0091] A method for measuring the thickness deformation of bentonite waterproof blanket samples includes the following steps:

[0092] 1) Zeroing the dial indicator 600: After setting the first permeable stone, the first filter paper, the second filter paper, and the second permeable stone in order from top to bottom, place them in the test interval between the sample base 210 and the sample top cover 220, and then seal them with latex film; the mounting head 410 at the lower end of the guide rod 400 is engaged with the top cover connector 300; apply confining pressure and back pressure to the osmotic pressure chamber according to the test standard requirements, and adjust the position of the instrument mounting base 500 in the vertical direction; when the lower end of the rod 620 of the dial indicator 600 installed on the instrument mounting base 500 contacts the top end of the guide rod 400, tighten the first fastener 540 to fix the position of the instrument mounting base 500, zero the dial indicator 600, and then tighten the second fastener 580 to fix the position of the dial indicator 600 to prevent the dial indicator 600 from sliding;

[0093] 2) Inserting Geotextile: Without changing the position of dial gauge 600, remove the permeability pressure chamber; shake off the bentonite in the bentonite waterproof blanket sample, leaving the geotextile in the bentonite waterproof blanket sample; according to the test standard requirements, arrange the first permeable stone, the first filter paper, the geotextile, the second filter paper, and the second permeable stone in order from top to bottom, and place them in the test interval between the sample base 210 and the sample top cover 220, and then seal them with latex film; connect the mounting head 410 at the lower end of the guide rod 400 to the top cover connector 300; apply the confining pressure and back pressure specified in the test to the permeability pressure chamber, and record the thickness value of the geotextile with dial gauge 600;

[0094] 3) Load the complete bentonite waterproof blanket sample; without changing the position of dial gauge 600, remove the osmotic pressure chamber; arrange the first permeable stone, the first filter paper, the bentonite waterproof blanket sample, the second filter paper, and the second permeable stone in order from top to bottom, and place them in the test interval between the sample base 210 and the sample top cover 220, and then seal them with latex film; engage the mounting head 410 at the lower end of the guide rod 400 with the top cover connector 300; under the confining pressure and back pressure conditions specified in the test standard, the bentonite waterproof blanket sample is hydrated and saturated, and then the upstream back pressure at the bottom of the bentonite waterproof blanket sample is increased to form an effective osmotic pressure, and seepage occurs from bottom to top; measure the volume of seeping liquid, the seepage time, and record the head difference between the two ends of the bentonite waterproof blanket sample and the total thickness of the bentonite waterproof blanket sample.

[0095] 4) Calculation: Bentonite thickness = Total thickness - Geotextile thickness.

[0096] In the bentonite waterproof blanket sample thickness deformation measurement method of the present invention, after the mounting head 410 at the lower end of the guide rod 400 rotates in the mounting groove 310 of the top cover connector 300, the mounting head 410 of the guide rod 400 and the top cover connector 300 form an interlocking connection, and the guide rod 400 is connected to the sample top cover 220; the connection between the mounting head 410 of the guide rod 400 and the top cover connector 300 is convenient and not easy to slip off.

[0097] The bentonite waterproof blanket sample thickness deformation measurement method of the present invention can track the deformation of bentonite sample thickness while testing the permeability of bentonite waterproof blanket 800. Under the combined action of confining pressure and counter pressure, the thickness of bentonite sample in the final saturated, hydrated, and consolidated state is measured, thus obtaining the effective permeability of bentonite sample. Based on the thickness of bentonite sample, the permeability coefficient of bentonite waterproof blanket 800 can be accurately calculated. The bentonite waterproof blanket sample thickness deformation measurement device of the present invention can test the thickness of bentonite sample without peeling off the geotextile on the bentonite sample.

[0098] The bentonite waterproof blanket sample thickness deformation measurement method of the present invention can be directly installed on the osmosis pressure chamber of an existing flexible wall vertical permeameter, requiring only a through hole 121 for the guide rod 400 to pass through on the pressure chamber top cover 120 of the osmosis pressure chamber.

[0099] The distance between the two parallel sidewalls 311 of the mounting groove 310 is the width W4 of the mounting groove 310;

[0100] The mounting head 410 includes an upper mounting part 411, a middle mounting part 412, and a lower mounting part 413 connected sequentially from top to bottom. The width W1 of both the middle mounting part 412 and the lower mounting part 413 is less than the distance L1 of the block spacing 331 between the two protrusions 330. The length K2 of the middle mounting part 412 is less than the distance L1 of the block spacing 331 between the two protrusions 330. The length K3 of the lower mounting part 413 is greater than the distance L1 of the block spacing 331 between the two protrusions 330. The length K3 of the lower mounting part 413 is less than the width W4 of the mounting groove 310. The length K1 of the upper mounting part 411 is greater than the distance L1 of the block spacing 331 between the two protrusions 330.

[0101] The width W1 of both the intermediate mounting portion 412 and the lower mounting portion 413 is less than the distance L1 of the block spacing 331 between the two protrusions 330, allowing the intermediate mounting portion 412 and the lower mounting portion 413 to pass through the block spacing 331 between the two protrusions 330; the length K2 of the intermediate mounting portion 412 is less than the distance L1 of the block spacing 331 between the two protrusions 330; the length K3 of the lower mounting portion 413 is greater than the distance L1 of the block spacing 331 between the two protrusions 330; the length K3 of the lower mounting portion 413 is less than the width W4 of the mounting groove 310. This structure allows the mounting head 410 to... The middle mounting part 412 can rotate within the block gap 331 between the two protrusions 330. The lower mounting part 413 of the mounting head 410 can rotate below the protrusions 330. After the lower mounting part 413 rotates 90 degrees, the two protrusions 330 prevent the lower mounting part 413 of the mounting head 410 from disengaging from the mounting groove, and the mounting head 410 forms an interlocking connection with the top cover connector 300. Since the length K1 of the upper mounting part 411 is greater than the distance L1 between the block gap 331 between the two protrusions 330, after the lower mounting part 413 rotates 90 degrees, the upper mounting part 411 abuts against the top surface of the top cover connector 300.

[0102] In this embodiment, the guide rod 400 is cylindrical. The top cover connector 300 is cylindrical, and the mounting groove 310 extends radially along the top cover connector 300. The lower mounting portion 413 is rectangular. The middle mounting portion 412 is cylindrical, so the width of the middle mounting portion 412 is equal to the length K2 of the middle mounting portion 412.

[0103] The bottom wall 312 of the mounting groove 310 is parallel to the top surface of the top cover connector 300, and the top surface of the top cover connector 300 is parallel to the horizontal plane; the distance L2 between the bottom surface of the protrusion 330 and the bottom wall 312 of the mounting groove 310 is greater than the vertical height H3 of the lower mounting part 413. This structure provides space below the protrusion 330 for the lower mounting part 413 to rotate.

[0104] The vertical height H4 of the protrusion 330 is less than or equal to the vertical height H2 of the intermediate mounting portion 412. This structure allows the lower mounting portion 413 to extend under the protrusion 330, so that the mounting head 410 and the top cover connector 300 form an interlocking connection.

[0105] The lower mounting part 413 has a rectangular cross-section, and the four corners of the bottom of the lower mounting part 413 are chamfered. The chamfering facilitates the insertion of the lower mounting part 413 into the block gap 331 between the two protrusions 330.

[0106] The main body 610 is connected to the stem 620 via the lower sleeve 630; a support rod 700 is provided on the top surface of the top cover connector 300, and the central axis of the support rod 700 is perpendicular to the horizontal plane.

[0107] The length of the instrument mounting base 500 is parallel to the horizontal plane; the two ends of the instrument mounting base 500 in the length direction are the instrument mounting end and the support mounting end, respectively.

[0108] The instrument mounting base 500 has a support mounting through hole 510, a support adjustment slot 520, and a support adjustment through hole 530 on its support mounting end. The support adjustment slot 520 extends to the end face of the support mounting end of the instrument mounting base 500. The central axis of the support mounting through hole 510 is vertically set. Both the support mounting through hole 510 and the support adjustment through hole 530 are connected to the support adjustment slot 520. The central axis of the support mounting through hole 510 is perpendicular to the central axis of the support adjustment through hole 530. The support mounting through hole 510 allows the support rod 700 to be inserted. The first fastener 540 is connected to the support adjustment through hole 530, so that the support mounting through hole 510 clamps the support rod 700.

[0109] The instrument mounting base 500 has an instrument mounting through hole 550, an instrument adjustment slot 560, and an instrument adjustment through hole 570 on its instrument mounting end. The instrument adjustment slot 560 extends to the end face of the instrument mounting end of the instrument mounting base 500. The central axis of the instrument mounting through hole 550 is vertically set. Both the instrument mounting through hole 550 and the instrument adjustment through hole 570 are connected to the instrument adjustment slot 560. The central axis of the instrument adjustment through hole 570 is perpendicular to the central axis of the instrument mounting through hole 550. The instrument mounting through hole 550 allows the lower sleeve rod 630 to be inserted. The second fastener 580 is connected to the instrument adjustment through hole 570, so that the instrument mounting through hole 550 clamps the lower sleeve rod 630.

[0110] When the first fastener 540 is not tightened, the instrument mounting base 500 can move along the support rod 700, thus adjusting the vertical position of the instrument mounting base 500. When the lower end of the dial indicator 620 mounted on the instrument mounting base 500 contacts the top end of the guide rod 400, tighten the first fastener 540 to fix the position of the instrument mounting base 500; tighten the second fastener 580 to fix the position of the dial indicator 600 to prevent the dial indicator 600 from sliding.

[0111] The upper end of the guide rod 400 extends through the through hole 121, and a sealing gasket is installed between the guide rod 400 and the through hole 121 to achieve a sealing effect in the osmotic pressure chamber.

[0112] The top surface of the sample top cover 220 is bonded to or threaded to the top cover connector 300. In this embodiment, the top surface of the sample top cover 220 is threaded to the top cover connector 300, and the top surface of the sample top cover 220 is provided with a receiving threaded hole. The bottom of the top cover connector 300 is provided with a mounting post 340, and the mounting post 340 is provided with an external threaded portion. The receiving threaded hole is threaded to the mounting post 340.

[0113] The method for measuring the thickness deformation of bentonite waterproof blanket samples of the present invention solves the problem that the thickness of bentonite cannot be accurately measured and the permeability coefficient of bentonite samples cannot be accurately calculated in the permeability performance test of bentonite waterproof blanket 800. In this embodiment, the bentonite thickness is the effective permeability diameter of the bentonite, and then the permeability coefficient is calculated according to Darcy's law.

[0114] In summary, this invention effectively overcomes the various shortcomings of the prior art and has high industrial application value.

[0115] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A method for measuring the thickness deformation of a bentonite waterproof blanket sample, characterized in that: A bentonite waterproof blanket sample thickness deformation measuring device is used. The bentonite waterproof blanket sample thickness deformation measuring device is installed on a osmotic pressure chamber. The osmotic pressure chamber includes an osmotic pressure cylinder (110). A pressure chamber top cover (120) is installed at the upper end of the osmotic pressure cylinder (110), and a pressure chamber base (130) is installed at the lower end of the osmotic pressure cylinder (110). The inside of the osmotic pressure cylinder (110) has a sample base (210) and a sample top cover (220) located directly above the sample base (210). There is a test interval between the sample base (210) and the sample top cover (220). The sample base (210) is connected to the upstream water inlet pipe (230) of the base body. The sample top cover (220) is connected to the downstream water inlet pipe (240) of the cover body. The top surface of the sample top cover (220) is provided with a top cover connector (300), and the top surface of the top cover connector (300) is provided with a mounting groove (310). The upper ends of the two parallel groove sidewalls (311) of the mounting groove (310) are provided with protrusions (330). The two protrusions (330) are arranged opposite to each other, and there is a block gap (331) between the two protrusions (330); the pressure chamber top cover (120) is provided with a through hole (121). The bentonite waterproof blanket sample thickness deformation measuring device includes: A guide rod (400) has its upper end protruding through the through hole (121); the lower end of the guide rod (400) is provided with a mounting head (410), which is inserted into the mounting groove (310). After the mounting head (410) rotates below the protrusion (330), the two protrusions (330) prevent the mounting head (410) from disengaging from the mounting groove (310). The mounting head (410) is connected to the top cover connector (300). An instrument mounting bracket (500) is installed on the pressure chamber top cover (120); A dial indicator (600) includes a body (610) and a stem (620) connected to the body (610). The body (610) is mounted on the instrument mounting base (500), and the lower end of the stem (620) contacts the top end of the guide rod (400). A method for measuring the thickness deformation of bentonite waterproof blanket samples includes the following steps: 1) Zeroing the dial indicator (600): After setting the first permeable stone, the first filter paper, the second filter paper, and the second permeable stone in order from top to bottom, place them in the test interval between the sample base (210) and the sample top cover (220), and then seal them with latex film; connect the mounting head (410) at the lower end of the guide rod (400) to the top cover connector (300); apply confining pressure and back pressure to the permeation pressure chamber, and adjust the position of the instrument fixing seat (500) in the vertical direction; when the lower end of the rod (620) of the dial indicator (600) installed on the instrument fixing seat (500) contacts the top end of the guide rod (400), tighten the first fastener (540) to fix the position of the instrument fixing seat (500), zero the dial indicator (600), and then tighten the second fastener (580) to fix the position of the dial indicator (600) to prevent the dial indicator (600) from sliding; 2) Insert geotextile: Without changing the position of the dial gauge (600), remove the permeation pressure chamber; shake off the bentonite in the bentonite waterproof blanket sample, leaving the geotextile in the bentonite waterproof blanket sample; after setting the first permeable stone, the first filter paper, the geotextile, the second filter paper, and the second permeable stone in order from top to bottom, place them in the test interval between the sample base (210) and the sample top cover (220), and then seal them with latex film; connect the mounting head (410) at the lower end of the guide rod (400) to the top cover connector (300); apply confining pressure and back pressure to the permeation pressure chamber, and record the thickness value of the geotextile with the dial gauge (600); 3) Load the complete bentonite waterproof blanket sample; without changing the position of the dial gauge (600), remove the osmotic pressure chamber; after setting the first permeable stone, the first filter paper, the bentonite waterproof blanket sample, the second filter paper, and the second permeable stone in order from top to bottom, place them in the test interval between the sample base (210) and the sample top cover (220), and then seal them with latex film; connect the mounting head (410) at the lower end of the guide rod (400) to the top cover connector (300); under confining pressure and back pressure conditions, the bentonite waterproof blanket sample is hydrated and saturated, and then the upstream back pressure at the bottom of the bentonite waterproof blanket sample is increased to form an effective osmotic pressure, and seep from bottom to top; measure the volume of seeping liquid, the seepage time, and record the head difference at both ends of the bentonite waterproof blanket sample and the total thickness of the bentonite waterproof blanket sample. 4) Calculation: Bentonite thickness = Total thickness - Geotextile thickness.

2. The method for measuring the thickness deformation of bentonite waterproof blanket samples according to claim 1, characterized in that: The distance between the two parallel sidewalls (311) of the mounting groove (310) is the width of the mounting groove (310); The mounting head (410) includes an upper mounting part (411), a middle mounting part (412), and a lower mounting part (413) connected sequentially from top to bottom; the width of the middle mounting part (412) and the width of the lower mounting part (413) are both less than the distance of the block spacing (331) between the two protrusions (330); the length of the middle mounting part (412) is less than the distance of the block spacing (331) between the two protrusions (330); the length of the lower mounting part (413) is greater than the distance of the block spacing (331) between the two protrusions (330); the length of the lower mounting part (413) is less than the width of the mounting groove (310); and the length of the upper mounting part (411) is greater than the distance of the block spacing (331) between the two protrusions (330).

3. The method for measuring the thickness deformation of bentonite waterproof blanket samples according to claim 2, characterized in that: The bottom wall (312) of the mounting groove (310) is parallel to the top surface of the top cover connector (300), and the top surface of the top cover connector (300) is parallel to the horizontal plane; the distance between the bottom surface of the protrusion (330) and the bottom wall (312) of the mounting groove (310) is greater than the vertical height of the lower mounting part (413).

4. The method for measuring the thickness deformation of bentonite waterproof blanket samples according to claim 2, characterized in that: The vertical height of the protrusion (330) is less than or equal to the vertical height of the intermediate mounting part (412).

5. The method for measuring the thickness deformation of bentonite waterproof blanket samples according to claim 2, characterized in that: The lower mounting part (413) has a rectangular cross-section, and the four corners of the bottom of the lower mounting part (413) are chamfered.

6. The method for measuring the thickness deformation of bentonite waterproof blanket samples according to claim 1, characterized in that: The main body (610) of the watch is connected to the watch rod (620) via the lower sleeve rod (630); a support rod (700) is provided on the top surface of the top cover connector (300), and the central axis of the support rod (700) is perpendicular to the horizontal plane. The length direction of the instrument mounting base (500) is parallel to the horizontal plane; the two ends of the instrument mounting base (500) in the length direction are the instrument mounting end and the support mounting end, respectively. The instrument mounting base (500) has a support mounting through hole (510), a support adjustment slot (520), and a support adjustment through hole (530) on its support mounting end. The support adjustment slot (520) extends to the end face of the support mounting end of the instrument mounting base (500). The central axis of the support mounting through hole (510) is vertically arranged. Both the support mounting through hole (510) and the support adjustment through hole (530) are connected to the support adjustment slot (520). The central axis of the support mounting through hole (510) is perpendicular to the central axis of the support adjustment through hole (530). The support mounting through hole (510) is for the support rod (700) to be inserted. A first fastener (540) is connected to the support adjustment through hole (530) so that the support mounting through hole (510) clamps the support rod (700). The instrument mounting base (500) has an instrument mounting through hole (550), an instrument adjustment slot (560), and an instrument adjustment through hole (570) on its instrument mounting end. The instrument adjustment slot (560) extends to the end face of the instrument mounting end of the instrument mounting base (500). The central axis of the instrument mounting through hole (550) is vertically set. Both the instrument mounting through hole (550) and the instrument adjustment through hole (570) are connected to the instrument adjustment slot (560). The central axis of the instrument adjustment through hole (570) is perpendicular to the central axis of the instrument mounting through hole (550). The instrument mounting through hole (550) is for the lower sleeve rod (630) to be inserted. The second fastener (580) is connected to the instrument adjustment through hole (570) so that the instrument mounting through hole (550) clamps the lower sleeve rod (630).

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