CN108507844B

CN108507844B - Hollow cylinder soft clay sample cutting instrument

Info

Publication number: CN108507844B
Application number: CN201810214012.2A
Authority: CN
Inventors: 郭林; 王军; 冯东; 符洪涛; 孙文涛
Original assignee: Wenzhou University
Current assignee: Wenzhou University
Priority date: 2018-03-15
Filing date: 2018-03-15
Publication date: 2020-12-04
Anticipated expiration: 2038-03-15
Also published as: CN108507844A

Abstract

The invention discloses a hollow cylindrical soft clay sample cutting instrument which comprises a base, a supporting upright post, a lower pedestal, a top pedestal, a rotary cutting hand wheel, a push rod, a cutting saw and a double-petal die, wherein the rotary cutting hand wheel comprises an upper wheel and a lower wheel; the pedestal piston penetrates through the pedestal piston and is fixed on the pedestal on the lower part by the upper piston wheel and the lower piston wheel, the pedestal on the top is also fixed on the upper part of the supporting upright by four bolts, the circular pedestal piston is fixed on the pedestal on the top by the upper piston wheel and the lower piston wheel, the lower wheel is fixed on the upper part of the pedestal by a fixing component on the pedestal, and the rigid rod piece drives the upper wheel and the lower wheel to rotate so as to drive the steel wire to cut the inside of the soil sample. The combination and installation of all parts of the device follow the order from bottom to top in the sample preparation process, and the sample cutting is according to the order of inside first and outside, thereby ensuring that the disturbance to the original structure of the soil sample is as little as possible, and preparing the high-quality sample.

Description

Hollow cylinder soft clay sample cutting instrument

Technical Field

The invention relates to a hollow cylinder soft clay sample cutting instrument, belongs to the technical field of geotechnical engineering test instrument manufacturing, and is suitable for manufacturing an original or remolded hollow cylinder soft clay sample and placing the original or remolded hollow cylinder soft clay sample in a hollow cylinder torsional shearing system for soil test research.

Background

In the field of geotechnical engineering, accurate and reliable soil physical and mechanical parameters are not required to be obtained, and a well-designed geotechnical test instrument is required to be used. Firstly, according to the national standard of the people's republic of China, namely the Standard of soil test methods (GB/T50123-1999), scientific, normative and effective methods need to be adopted to obtain and prepare soil samples. The method is also an important guarantee for obtaining various soil physical property indexes with higher reliability in the subsequent test process, and provides guidance for further engineering investigation, design and construction. Moreover, the invention is used for the indoor unit body test, and has higher requirements on the initial acquisition and manufacture of the soil sample. Therefore, the research of a set of scientific, fine and standard soil sample preparation device is often the foundation of successful experimental research.

Soil samples generally include undisturbed soil, disturbed soil and remolded soil samples. At present, as the soil body properties of different regions have larger differences, undisturbed soil samples of all regions are mainly adopted in experimental research, so that the local engineering design and construction are safer and more reliable, and the local conditions are met. However, with the continuous and deep development of scientific research, researchers are eagerly searching for the law of more uniformity of the soil, and the research results are expected to be widely applied to engineering construction in different areas. Therefore, remolded soil samples are also increasingly being used in laboratories. The remolded soil is a soil sample between undisturbed soil and disturbed soil, is formed by the disturbed soil and is used for a test through artificial simulation. Its detailed definition can be expressed as: the remolded soil is a disturbed soil body structure which is artificially and purposefully shaped and has the basic characteristics of the appearance of an imitated original soil body, and is a test soil body applied to realizing a certain research purpose. In the soil test, remolded soil is adopted for the experiment, and the advantages of low sample preparation cost, good sample uniformity, reusability and the like enable the test result to have comparability and regularity, thus providing a foundation for researchers to discover and summarize soil body rules and further achieving the purpose of scientific research.

Taking weak cohesive soil as an example, the hollow cylindrical sample required in the current hollow torsional shear test is generally prepared by vacuum suction direct drainage molding (remolding soil sample) or by a method of internal coring and external cutting (remolding soil and undisturbed soil) after prepressing drainage consolidation. In the former, the drainage consolidation mode of the soil body is greatly different from the situation in the actual stratum, and the inner wall and the outer wall of the sample prepared by the method are not smooth enough, and the appearance is rough; in the latter, the mode of internal coring and hollowing needs a large external force, the disturbance of the external force on the consolidated and formed soil body is large, the sample preparation time is long, and particularly under the condition that the water content of the soil body is relatively high, low or uneven in distribution, the sample wall is easy to break in the sample preparation process, so that the sample preparation fails. Therefore, in view of the above-mentioned troublesome sample preparation problems, a sample preparation apparatus that is less disturbed in the soil and can rapidly prepare a sample is needed. The device can just effectively solve the problems so as to meet the increasing requirements of hollow cylinder torsional shear tests.

Technical content

The invention aims to solve the technical problem that sample preparation greatly disturbs the soil body in the existing hollow cylinder torsional shear test, and provides a hollow cylinder soft clay sample cutting instrument which is convenient and practical and can realize rapid sample preparation.

In order to solve the technical problems, the invention adopts the following specific technical scheme: the cutting instrument for the hollow cylindrical soft clay sample comprises a base, a supporting upright post, a lower pedestal, a top pedestal, a rotary cutting hand wheel, a push rod, a cutting saw and a double-petal die, wherein the rotary cutting hand wheel comprises an upper wheel and a lower wheel; the upper part of the base is provided with a fixing component for fixing the lower wheel inside the sample, and is provided with four bolt holes for fixing a supporting upright column, the lower part of the supporting upright column is screwed in and fixed on the base, the middle part and the upper part of the supporting upright column are respectively used for fixing a lower pedestal and a top pedestal, the lower pedestal is fixed in the middle part of the supporting upright column through four bolts and is used for supporting a soil sample placed on the upper part of the supporting upright column, a round pedestal piston penetrates through the pedestal piston and is fixed on the lower pedestal through an upper piston wheel and a lower piston wheel, the piston can move up and down and freely rotate and is used for adjusting the position of the soil sample up and down and rotating the soil sample so as to be cut, the top pedestal is also fixed on the upper part of the supporting upright column through four bolts and is used for compressing the soil sample from the upper part, the round pedestal piston is fixed on the top pedestal, the lower wheel is fixed on the upper portion of the base through a fixing component on the base, the upper wheel is sleeved on the upper portion of a piston of the pedestal at the top, the upper wheel and the lower wheel can rotate freely and are connected through a cutting steel wire inside the soil sample, two ends of the steel wire are tensioned by fixing bolts, straightened and fixed on two hand wheels, at least two rigid rod pieces are embedded and fixed between the two wheels, the two rigid rod pieces are simultaneously stirred by two hands in the test process, and the rigid rod pieces drive the upper wheel and the lower wheel to rotate so as to drive the steel wire to cut the inside of the soil sample.

The hollow cylindrical soft clay sample cutting instrument provided by the invention adopts a linear (thin steel wire) cutting mode for a soil sample, can effectively cut an original or remolded soft clay sample and quickly prepare the soil sample. It is additionally stated here that the soil sample to be cut should have the appropriate dimensional requirements (the outer diameter and height should be ensured to be larger than the size of the sample to be cut at the end) to ensure that a hollow cylindrical sample of full size can be prepared. In addition, the combination and installation of all parts of the device are in the sequence from bottom to top in the sample preparation process, and the sample cutting is performed in the sequence from inside to outside so as to ensure that the disturbance on the original structure of the soil sample is as small as possible, thereby preparing the high-quality sample.

Drawings

FIG. 1 is a schematic structural diagram of a hollow cylindrical soft clay sample cutting instrument according to the present invention;

FIG. 2 is a front view and a perspective view of the base structure of FIG. 1;

FIG. 3 is a front view and a perspective view of the lower stage structure of FIG. 1;

FIG. 4 is a front view and a perspective view of the hollow cylindrical test piece of FIG. 1;

FIG. 5 is a front view and a perspective view of the top deck structure of FIG. 1;

FIG. 6 is an elevational view and a perspective view of the rotary cutting handwheel of FIG. 1;

FIG. 7 is a front view and a perspective view of the putter structure of FIG. 1;

FIG. 8 is a front view and a perspective view of the support column structure of FIG. 1;

fig. 9 is a front view and a perspective view of the double petal design of fig. 1.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

Referring to fig. 1-9, the main structure of the hollow cylindrical soft clay sample cutting instrument provided by the invention comprises a base 1, a support column 3, a lower pedestal 5, a top pedestal 10, a rotary cutting hand wheel 2, a push rod 12, a cutting saw 15, a double-petal mold 22 and the like. The details of the various parts of the device will be described one by one from the bottom to the top.

Referring to the base 1 shown in fig. 2, the upper part of the base is provided with a fixing component for fixing the lower wheel of the rotary cutting hand wheel 2 in the sample, and four bolt holes for fixing the support upright post 3 are arranged.

Referring to FIG. 8, support column 3 is shown with its lower portion screwed into and fixed to base 1 and its middle and upper portions for fixing lower pedestal 5 and top pedestal 10, respectively.

Referring to the lower stand 5 shown in fig. 3, fixed to the middle of the support column 3 by four bolts 6 for supporting a soil sample 9 placed on the upper portion thereof, a circular stand piston 8 penetrates therethrough and is fixed to the lower stand 5 by upper and

lower piston wheels

4, 7, and the piston 8 can move up and down and freely rotate for adjusting the position of the soil sample 9 up and down and rotating the soil sample for cutting.

Referring to the top stand 10 shown in fig. 5, a circular stand piston 8 is fixed to the top stand 10 by upper and

lower piston wheels

4 and 11, and the stand piston 8 is also movable up and down and freely rotatable for pressing and rotating the soil sample 9 for cutting, and is also fixed to the upper portion of the support column 3 by four bolts 6 for pressing the soil sample 9 from above.

Referring to fig. 6, there is shown a rotary cutting handwheel 2, which has two upper and lower wheels, the lower wheel is fixed on the upper part of the base by

fixing members

19, 20 on the base 1, the upper wheel is sleeved on the upper part of the top pedestal piston 8, both wheels can freely rotate and are connected by

cutting wires

14, 18 inside the soil sample, the

cutting wires

14, 18 are thin wires, and both ends of the

cutting wires

14, 18 are tightened by fixing bolts 13, straightened and fixed on the handwheels 2. In order to make the two wheels synchronously rotate, two rigid rods 3 are embedded between the two wheels, the pedestal piston 8 is provided with an inner hole, the

cutting steel wires

14 and 18 respectively penetrate through the lower pedestal 5, the lower pedestal piston 8, the upper pedestal piston 8 and the top pedestal 10 in sequence, and the

cutting steel wires

14 and 18 are attached to the inner wall of the inner hole of the pedestal piston 8. In the test process, two rod pieces are simultaneously stirred by two hands, and the upper hand wheel and the lower hand wheel are driven by the rod pieces to rotate so that the steel wires simultaneously move to cut the inside of the soil sample 9.

Referring to the push rod 12 shown in fig. 7, when the rotating hand wheel 2 is rotated to cut the inside of the soil sample, the push rod 12 penetrates through the top pedestal piston 8 from above and applies a certain pushing force to the inner core of the soil sample 9, so that the inner core of the soil sample rapidly penetrates through the hollow lower pedestal piston 8 downwards under the action of gravity and the pushing force and is taken out by hand from below the lower pedestal, and the inside cutting of the sample is completed.

Referring to fig. 1, a cutting saw 15 is shown, in which a saw blade 17 is a thin steel wire fixed to screws 16 at both ends of the saw for cutting the outer wall and upper and lower ends of a soil sample 9 and ensuring that it is flat and smooth.

Referring to fig. 9, a bivalve mold 22 is shown, which is two semicircular rigid and light mold halves, and after coating vaseline on the inner wall of the bivalve mold, the bivalve mold is used for clamping and taking off the soil sample from the device after the inner wall and the outer wall are cut, and cutting off the redundant part of the soil sample along two ends of the mold halves by a cutting saw, and after the two mold halves are removed, the hollow cylinder soft clay sample 9 can be obtained finally.

The above embodiment is only a preferred embodiment of the present invention, however, it is not intended to limit the present invention, and all technical solutions obtained by equivalent transformation or equivalent substitution fall within the protection scope of the present invention.

Claims

1. A hollow cylindrical soft clay sample cutting instrument comprises a base (1), a supporting upright post (3), a lower pedestal (5), a top pedestal (10), a rotary cutting hand wheel (2), a push rod (12), a cutting saw (15) and a double-petal die (22), wherein the rotary cutting hand wheel (2) comprises an upper wheel and a lower wheel; the upper part of the base (1) is provided with a fixing component for fixing the lower wheel inside the sample, and is provided with four bolt holes for fixing a supporting upright post (3), the lower part of the supporting upright post (3) is screwed in and fixed on the base (1), the middle part and the upper part of the supporting upright post (3) are respectively used for fixing a lower pedestal (5) and a top pedestal (10), the lower pedestal (5) is fixed in the middle part of the supporting upright post (3) through four bolts (6) and is used for supporting a soil sample (9) placed on the upper part of the supporting upright post, a circular pedestal piston (8) passes through the pedestal piston and is fixed on the lower pedestal (5) through upper and lower piston wheels (4 and 7), the pedestal piston (8) can move up and down and rotate freely and is used for adjusting the position of the soil sample (9) up and down and rotating the soil sample so as to cut, the top pedestal (10) is also fixed on the upper part of the supporting upright post (, for pressing a soil sample (9) from the upper part, a circular pedestal piston (8) is fixed on a top pedestal (10) by upper and lower piston wheels (4, 11), the piston can also move up and down and rotate freely for pressing and rotating the soil sample (9) for cutting, the lower wheel is fixed on the upper part of the base through fixing components (19, 20) on the base (1), the upper wheel is sleeved on the upper part of the top pedestal piston (8), the upper wheel and the lower wheel can both freely rotate, the soil sample cutting device is characterized in that the soil sample cutting device is connected through cutting steel wires (14 and 18) inside a soil sample, two ends of the cutting steel wires (14 and 18) are tensioned by a fixing bolt (13), straightened and fixed on two hand wheels (2), at least two rigid rod pieces are embedded and fixed between two wheels, the two rigid rod pieces are simultaneously stirred by two hands in the test process, and an upper wheel and a lower wheel are driven by the rigid rod pieces to rotate so as to drive the steel wires to cut the inside of the soil sample (9); when rotating rotatory hand wheel (2) and cutting inside the soil sample, through push rod (12) pass top pedestal piston (8) from the top and exert the jacking force to the inner core of soil sample (9) simultaneously for the inner core of soil sample is quick under the effect of gravity and jacking force and is passed piston (8) in the hollow lower part pedestal downwards to take out with the hand from the below of lower part pedestal, thereby accomplish the inside cutting of sample.

2. The hollow cylindrical soft clay sample cutting instrument according to claim 1, wherein: the cutting saw (15) comprises a saw blade (17), wherein the saw blade (17) is a thin steel wire and is fixed on screws (16) at two ends of the cutting saw (15).

3. The hollow cylindrical soft clay sample cutting instrument according to claim 1 or 2, characterized in that: the double-petal mould (22) is composed of two semicircular rigid and light mould petals, and vaseline is coated on the inner wall of the double-petal mould (22).

4. The hollow cylindrical soft clay sample cutting instrument according to claim 1 or 2, characterized in that: pedestal piston (8) have the hole, cutting steel wire (14, 18) pass lower part pedestal (5), pedestal piston (8) of lower part, pedestal piston (8) and top pedestal (10) on upper portion respectively, cutting steel wire (14, 18) are pasted the inner wall of pedestal piston (8) hole.

5. The hollow cylindrical soft clay sample cutting instrument according to claim 3, wherein: pedestal piston (8) have the hole, cutting steel wire (14, 18) pass lower part pedestal (5), pedestal piston (8) of lower part, pedestal piston (8) and top pedestal (10) on upper portion respectively, cutting steel wire (14, 18) are pasted the inner wall of pedestal piston (8) hole.