JPH1164202A - Method and device for testing shear strength - Google Patents
Method and device for testing shear strengthInfo
- Publication number
- JPH1164202A JPH1164202A JP22526097A JP22526097A JPH1164202A JP H1164202 A JPH1164202 A JP H1164202A JP 22526097 A JP22526097 A JP 22526097A JP 22526097 A JP22526097 A JP 22526097A JP H1164202 A JPH1164202 A JP H1164202A
- Authority
- JP
- Japan
- Prior art keywords
- specimen
- shear strength
- storage container
- strength test
- stress
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
Landscapes
- Investigation Of Foundation Soil And Reinforcement Of Foundation Soil By Compacting Or Drainage (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
Description
【0001】[0001]
【発明の属する技術分野】本発明は、乾湿繰り返しによ
りスレーキングが発生して軟弱化する軟岩類からなる盛
土材料などの土のせん断強度を求めるための強度試験技
術に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a strength test technique for determining the shear strength of soil, such as an embankment material made of soft rocks, which softens due to slaking due to repeated wet and dry.
【0002】[0002]
【従来の技術】泥岩や頁岩、凝灰岩、砂岩などの軟岩類
を切土して盛土すると盛土当初は安定していても、その
後の長時間にわたって受ける乾湿繰り返しによりスレー
キングが発生して軟弱化する。2. Description of the Related Art When soft rocks such as mudstone, shale, tuff, sandstone, etc. are cut and buried, embankment is stable at the beginning of the embankment, but slaking occurs due to repeated dry and wet after a long period of time and softens.
【0003】軟岩類からなる盛土材料の強度は、盛土し
た後に受ける乾湿繰り返し(主に晴天による乾燥状態
と、降雨や地下水位上昇などによる湿潤状態との繰り返
し)により軟弱化した状態での値を求める必要がある。[0003] The strength of the embankment material composed of soft rocks is a value obtained when the embankment is softened due to repeated wet and dry conditions after embankment (mainly a dry condition due to clear weather and a wet condition due to rainfall or rising groundwater level). Need to ask.
【0004】従来は、このようなスレーキング状態にお
ける土質試験技術としては、圧縮沈下特性を求めること
ができる試験装置の開発、実用化が知られている。Conventionally, as a technique of soil testing in such a slaking state, the development and commercialization of a test apparatus capable of determining the compression settling characteristics have been known.
【0005】[0005]
【発明が解決しようとする課題】泥岩や頁岩、凝灰岩、
砂岩などの軟岩類からなる地盤を切土した材料で盛土す
ると、盛土地盤は盛土当初は安定していても、その後長
時間にわたって受ける乾湿繰り返しにより軟弱化して、
盛土地盤に大きな沈下が発生したり、あるいは盛土斜面
では強度低下によるすべりが発生したりする。SUMMARY OF THE INVENTION Mudstone, shale, tuff,
When embankment is made with a material obtained by cutting the ground made of soft rocks such as sandstone, the embankment is stable at the beginning of embankment, but softens due to repeated drying and wetness received for a long time afterwards.
Large subsidence occurs on the embankment, or slippage occurs on the embankment slope due to reduced strength.
【0006】そこで、かかるスレーキングが発生する盛
土地盤などの土質調査では、圧縮沈下特性と強度特性と
の両特性の調査が必要である。[0006] Therefore, in the investigation of soil properties such as embankment in which such slaking occurs, it is necessary to investigate both characteristics of compression settlement and strength.
【0007】しかし、スレーキング状態における圧縮沈
下特性を調査する試験技術は従来より知られているが、
強度特性試験の技術は未だ開発されていない。[0007] However, although a test technique for examining compression settling characteristics in a slaking state has been conventionally known,
The technology for strength property testing has not yet been developed.
【0008】本発明の目的は、乾湿繰り返しにより発生
するスレーキング状態における土のせん断強度が求めら
れるようにすることにある。[0008] It is an object of the present invention to obtain the shear strength of soil in a slaking state generated by repeated wet and dry.
【0009】本発明の前記ならびにその他の目的と新規
な特徴は、本明細書の記述および添付図面から明らかに
なるであろう。The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings.
【0010】[0010]
【課題を解決するための手段】本願において開示される
発明のうち、代表的なものの概要を簡単に説明すれば、
以下のとおりである。SUMMARY OF THE INVENTION Among the inventions disclosed in the present application, the outline of a representative one will be briefly described.
It is as follows.
【0011】例えば、立方体形状、あるいは直方体形状
に形成された供試体格納容器に、例えば、軟岩類からな
る地盤を切土して得られる盛土材料を土質調査試料とし
て入れる。For example, an embankment material obtained by cutting a ground made of soft rocks is put into a specimen storage container formed in a cubic shape or a rectangular parallelepiped shape as a soil investigation sample.
【0012】その後、供試体格納容器内に入れた土質調
査試料の盛土材料を、盛土する時と同じ含水状態でラン
マーやバイブレーターなどの締固め機械により締固めて
供試体を作製する。[0012] Thereafter, the embankment material of the soil investigation sample placed in the specimen storage container is compacted by a compaction machine such as a rammer or a vibrator under the same water-containing condition as when embankment is performed, to produce a specimen.
【0013】さらに、例えばシリンダ圧縮などの押圧手
段で、互いに直交する3軸方向からそれぞれ独立に押圧
して応力を加え、盛土された斜面や地盤内の応力状態に
合わせた条件設定を行う。[0013] Further, stress is applied by pressing independently from three axial directions perpendicular to each other by pressing means such as cylinder compression or the like, and conditions are set in accordance with the stress state in the embankment slope or ground.
【0014】3軸方向から独立に押圧手段で応力を加え
るには、例えば、上記要領で供試体格納容器内に作製し
た供試体に対して、鉛直下方に向けて押圧手段で最大主
応力(σ1 )を加える。併せて、上記最大主応力
(σ1 )方向と直交する水平方向から最小主応力
(σ3 )を独立して加えて、盛土された斜面や地盤内の
応力状態に合わせた条件設定を行う。In order to apply the stress by the pressing means independently from the three axial directions, for example, the maximum principal stress (σ 1 ) Add. At the same time, the minimum principal stress (σ 3 ) is independently added from the horizontal direction orthogonal to the maximum principal stress (σ 1 ) direction, and conditions are set in accordance with the embankment slope and the stress state in the ground.
【0015】かかる応力条件設定が行われた供試体に、
乾湿繰り返しを行ってスレーキングを発生させる。乾湿
繰り返しは、次のようにして行えばよい。[0015] A test piece having such stress conditions set therein is:
Slaking is generated by performing dry and wet cycles. The repetition of the wet and dry may be performed as follows.
【0016】供試体格納容器を内部に設けた環境条件設
定容器内を乾燥手段により乾燥環境にして、供試体格納
容器に設けた内外連通部を通して、上記応力条件を設定
した供試体を乾燥状態にする。The inside of the environment condition setting container in which the specimen storage container is provided is made into a dry environment by the drying means, and the specimen in which the above-mentioned stress condition is set is brought into a dry state through the inside / outside communication part provided in the specimen storage container. I do.
【0017】上記乾燥手段としては、例えば、環境条件
設定容器に吸気口と排気口とを設けておき、この吸気口
を外部の熱風発生機に接続して、環境条件設定容器内に
所定温度に設定した熱風を一定時間送り込む。送り込ん
だ熱風を、排気口から逃がすようにして、熱風が環境条
件設定容器内を通過するようにする。このようにして、
環境条件設定容器内を乾燥環境下に設定することができ
る。As the drying means, for example, an intake port and an exhaust port are provided in the environmental condition setting container, and the air intake port is connected to an external hot air generator so that the predetermined temperature is set in the environmental condition setting container. Send the set hot air for a certain period of time. The sent hot air is allowed to escape from the exhaust port so that the hot air passes through the environmental condition setting container. In this way,
The environment condition setting container can be set in a dry environment.
【0018】上記の如く、乾燥環境下の環境条件設定容
器内に置かれた供試体格納容器内では、上記供試体は内
外連通部を介して熱風に接して乾燥状態にされる。供試
体の乾燥に際して発生した水蒸気は、熱風とともに環境
条件設定容器外に排気されて、環境条件設定容器内の乾
燥環境を維持することができる。As described above, in the specimen storage container placed in the environmental condition setting container in a dry environment, the specimen is brought into a dry state by coming into contact with hot air through the inside / outside communication part. The water vapor generated at the time of drying the specimen is exhausted to the outside of the environmental condition setting container together with the hot air, so that the drying environment in the environmental condition setting container can be maintained.
【0019】一方、供試体の湿潤状態は次のようにして
行う。On the other hand, the wet state of the specimen is performed as follows.
【0020】供試体格納容器を内部に設けた環境条件設
定容器内を加湿手段により加湿環境にして、供試体格納
容器に設けた内外連通部を通して、上記応力条件を設定
した供試体を湿潤状態にする。The environment condition setting container in which the specimen storage container is provided is made humidified by the humidifying means, and the specimen in which the above-mentioned stress condition is set is brought into a wet state through the inside / outside communication part provided in the specimen storage container. I do.
【0021】加湿手段としては、例えば、環境条件設定
容器に給水口を設けておき、この給水口を外部の水栓な
どに接続して、環境条件設定容器内に水を送り込む。水
は、供試体格納容器が水没する程度に送り込めばよい。
このようにして、環境条件設定容器内で、供試体格納容
器を一定時間水没させて加湿環境下に置くことができ
る。As the humidifying means, for example, a water supply port is provided in the environmental condition setting container, and the water supply port is connected to an external faucet or the like, and water is sent into the environmental condition setting container. The water may be sent to such an extent that the specimen storage container is submerged.
In this way, the specimen storage container can be submerged for a certain period of time in the environmental condition setting container and placed in a humid environment.
【0022】上記の如く、水没による加湿環境下の環境
条件設定容器内に置かれた供試体格納容器内では、上記
供試体は内外連通部を介して水を吸収して湿潤状態にさ
れる。供試体が十分に湿潤状態になった時点で、排水口
から、環境条件設定容器内に入れた水を抜く。As described above, in the specimen storage container placed in the environmental condition setting container in a humid environment caused by submergence, the specimen is absorbed by the water via the internal / external communication part and is brought into a wet state. When the specimen becomes sufficiently wet, drain the water contained in the environmental condition setting container from the drain port.
【0023】上記構成の乾燥手段と、加湿手段とを所定
回数交互に繰り返すことにより、供試体に乾湿繰り返し
を行ってスレーキングを発生させる。このようにして、
供試体にスレーキングを発生させた状態で、強度試験を
行えばよい。By alternately repeating the drying means and the humidifying means a predetermined number of times, the sample is repeatedly dried and wet to generate slaking. In this way,
The strength test may be performed in a state where slaking has occurred in the test specimen.
【0024】強度試験は、例えば、上記要領でスレーキ
ングが発生した供試体に、上記最大主応力(σ1 )のみ
を増加させるなどして、上記構成の押圧手段に連動させ
た計測手段で測定した値をもとに供試体のせん断強度を
求めればよい。In the strength test, for example, only the maximum principal stress (σ 1 ) is increased on the specimen having the slaking as described above, and the measurement is performed by the measuring means linked to the pressing means having the above configuration. The shear strength of the specimen may be determined based on the value.
【0025】[0025]
【発明の実施の形態】以下、本発明の実施の形態を図面
に基づいて詳細に説明する。Embodiments of the present invention will be described below in detail with reference to the drawings.
【0026】(実施の形態1)本実施の形態では、平面
ひずみせん断強度試験ができるように、水平方向の供試
体の変位を拘束した構成のせん断強度試験装置について
説明する。(Embodiment 1) In this embodiment, a description will be given of a shear strength test apparatus having a configuration in which the displacement of a specimen in a horizontal direction is restricted so that a plane strain shear strength test can be performed.
【0027】かかる構成のせん断強度試験装置は、図1
に示すように、環境条件設定容器10内に、供試体格納
容器20を設置しておき、この供試体格納容器20内に
入れた土質調査試料に応力を加えたり、乾湿繰り返しを
行ったりして、スレーキング発生条件下でせん断強度試
験が行えるように構成されている。FIG. 1 shows a shear strength test apparatus having such a configuration.
As shown in (1), the specimen storage container 20 is installed in the environmental condition setting container 10, and stress is applied to the soil investigation sample placed in the specimen storage container 20, or the wet and dry operation is repeated. , So that a shear strength test can be performed under conditions of occurrence of slaking.
【0028】本実施の形態の環境条件設定容器10は、
図1、2に示すように、略円筒形に構成されており、円
形の底部11には、給・排水口12が設けられている。
給・排水口12は、曲がった短管状の管接続口12aに
構成されている。The environmental condition setting container 10 according to the present embodiment
As shown in FIGS. 1 and 2, it is formed in a substantially cylindrical shape, and a circular bottom portion 11 is provided with a supply / drain port 12.
The supply / drainage port 12 is formed as a bent short pipe connection port 12a.
【0029】また、底部11は、環境条件設定容器10
の設置面Sから少し立ち上げた形状で重量のある肉厚部
に形成されている。重量のある肉厚部に形成することに
より、後記するように、環境条件設定容器10内に設け
た供試体格納容器20に対して、上から最大主応力(σ
1 )を鉛直下方に向けて加えた際にも装置全体が安定し
ておけるようになっている。The bottom portion 11 is provided with an environmental condition setting container 10.
Is slightly raised from the installation surface S, and is formed in a thick part with a heavy weight. By forming the thick part with a heavy weight, as described later, the maximum principal stress (σ
Even when 1 ) is applied vertically downward, the entire device can be stabilized.
【0030】この底部11上に、供試体格納容器20の
底部21が固定されて、供試体格納容器20が、環境条
件設定容器10内に設けられている。底部21は、環境
条件設定容器10の底面11aから少し立ち上げた形状
の肉厚に形成されて、上面(底面21aに相当する)が
平面正方形状になるように設定されている。The bottom portion 21 of the specimen storage container 20 is fixed on the bottom 11, and the specimen storage container 20 is provided in the environmental condition setting container 10. The bottom portion 21 is formed to have a thickness slightly rising from the bottom surface 11a of the environmental condition setting container 10, and is set so that the top surface (corresponding to the bottom surface 21a) is a planar square shape.
【0031】底部21の平面部分中央には、多孔質部材
22aが、底面21aと面一になるようにして設けられ
ている。多孔質部材22aとしては、本実施の形態で
は、砥石を使用した。それ以外にも、水や空気を適当に
通過させることができる多数の孔のあいたポーラス板な
どの部材であればよい。A porous member 22a is provided at the center of the flat portion of the bottom portion 21 so as to be flush with the bottom surface 21a. In this embodiment, a grindstone is used as the porous member 22a. In addition, a member such as a porous plate having a large number of holes through which water and air can appropriately pass may be used.
【0032】また、かかる多孔質部材22aの底面側に
は、底部21の立ち上げ側面側から貫通孔22bが通じ
させられ、全体として内外連通部22が構成されてい
る。A through hole 22b is formed on the bottom surface of the porous member 22a from the rising side surface of the bottom portion 21 to form an inner / outer communication portion 22 as a whole.
【0033】かかる内外連通部22は、後で詳述する
が、環境条件設定容器10内の環境条件を供試体格納容
器20内の供試体側に及ぼすことができるように設けた
ものである。As will be described in detail later, the internal / external communication part 22 is provided so that the environmental conditions in the environmental condition setting container 10 can be exerted on the specimen side in the specimen storage container 20.
【0034】上記構成の平面正方形状の底部21上に
は、底部21の四方向を、図2に示すように、4枚の正
方形の肉厚の側板23a、23a’、23b、23b’
で囲むようにして、組立式の供試体格納容器20が設け
られている。本実施の形態では、説明上、上記側板23
aと側板23a’、側板23bと側板23b’とは互い
に対面する側に設けられ、側板23a(または、23
a’)と、側板23b(または23b’)とは互いに直
交する側に設けられているものとする。As shown in FIG. 2, the four directions of the bottom 21 are aligned with the four square side plates 23a, 23a ', 23b, 23b'.
A sample storage container 20 of an assembling type is provided so as to surround the container. In the present embodiment, the side plate 23
a and the side plate 23a 'and the side plate 23b and the side plate 23b' are provided on the sides facing each other, and the side plate 23a (or 23
a ') and the side plate 23b (or 23b') are provided on mutually orthogonal sides.
【0035】側板23a、23a’、23b、23
b’、およびは、底部21とは、それぞれ、図2に示す
ように、それぞれの端部側をネジNによりネジ止めして
箱型に組立できるように構成されている。Side plates 23a, 23a ', 23b, 23
As shown in FIG. 2, b ′ and the bottom 21 are configured to be assembled in a box shape by screwing each end side with a screw N.
【0036】特に、本実施の形態では、図3に示すよう
に、側板23b’(図示しないが、23bも同様)の両
端部には、側板23a、23a’の端面巾に合わせて組
付け凹部23cを設け、側板23a、23a’の端面を
組付け凹部23cに嵌めるようにして当接させた状態
で、ネジNでネジ止めされている。In particular, in the present embodiment, as shown in FIG. 3, both ends of the side plate 23b '(not shown, but the same applies to 23b) are provided with recesses according to the width of the end surfaces of the side plates 23a, 23a'. 23c is provided, and the end faces of the side plates 23a, 23a 'are screwed with screws N in a state where the end faces of the side plates 23a, 23a' are brought into contact with the assembling recess 23c.
【0037】このようにして、組み付けることにより、
後記する水没時に組付け部分から水が供試体格納容器2
0内に侵入したり、あるいは供試体格納容器20内から
土質調査試料が逃げたりなどしないようになっている。By assembling in this manner,
Specimen storage container 2 when water submerged
0 or the soil investigation sample does not escape from the specimen storage container 20.
【0038】また、側板23aには、図2に示すよう
に、供試体格納容器20の側面の水平方向に対しての変
位を拘束するための変位拘束手段30用の開口部24a
が設けられている。As shown in FIG. 2, the side plate 23a has an opening 24a for a displacement restricting means 30 for restricting the lateral displacement of the side surface of the specimen storage container 20 in the horizontal direction.
Is provided.
【0039】変位拘束手段30は、変位拘束装置31に
水平方向に連結されたシャフト32の先端側に供試体拘
束板33を設けて、シャフト32をガイドベアリング3
2aに支持させながら油圧により適宜位置に前後に移動
させた状態で、供試体拘束板33に加えられた圧力に抗
して動かないように(変位しないように)拘束できるよ
うになっている。The displacement restricting means 30 is provided with a specimen restricting plate 33 at the tip end of a shaft 32 connected to the displacement restricting device 31 in the horizontal direction.
In a state in which it is moved back and forth to an appropriate position by hydraulic pressure while being supported by 2a, it can be restrained so as not to move (do not displace) against the pressure applied to the test piece restraining plate 33.
【0040】本実施の形態では、供試体拘束板33はそ
の背面側が、シャフト32の先端側に直接設けた支持板
33aに平面的に支持されて、供試体拘束板33面に力
が加わっても、シャフト32の先端側で供試体拘束板3
3がふらつかずに、供試体拘束板33に加えられた力が
減ずることなくシャフト32方向に力が伝えられるよう
に構成されている。In the present embodiment, the back side of the test piece restraining plate 33 is planarly supported by a support plate 33a provided directly on the distal end side of the shaft 32, and a force is applied to the surface of the test piece restraining plate 33. The specimen restraining plate 3
It is configured such that the force applied to the test piece restraining plate 33 is transmitted in the direction of the shaft 32 without reducing the force applied to the specimen restraint plate 33 without wobbling.
【0041】さらに、本実施の形態では、シャフト32
と変位拘束装置31との間に、ロードセル40aが、計
測手段40として設けられている。Further, in this embodiment, the shaft 32
A load cell 40 a is provided as a measuring unit 40 between the displacement restraining device 31 and the displacement restricting device 31.
【0042】開口部24aは、供試体拘束板33を側板
23a内側にいっぱいに引くことができるように、支持
板33aが通せる程度の大きさに開口させられている。The opening 24a is formed in such a size that the support plate 33a can pass through so that the test sample restraining plate 33 can be fully pulled inside the side plate 23a.
【0043】また、環境条件設定容器10の円筒側面に
は、上記シャフト32が周囲を水漏れが発生しないよう
にシールされた状態で、環境条件設定容器10内に向け
て出入りできるように挿通させられている。上記ガイド
ベアリング32aは、シャフト32が挿通する円筒側面
外側に設けられている。The shaft 32 is inserted through the cylindrical side surface of the environmental condition setting container 10 so as to be able to enter and exit the environmental condition setting container 10 in a state where the shaft 32 is sealed so as not to cause water leakage. Have been. The guide bearing 32a is provided outside the cylindrical side surface through which the shaft 32 is inserted.
【0044】一方、側板23bには、図2に示すよう
に、供試体格納容器20の水平方向から応力を加えるた
めの押圧手段50用の開口部24bが設けられている。On the other hand, as shown in FIG. 2, the side plate 23b is provided with an opening 24b for the pressing means 50 for applying a stress from the horizontal direction of the specimen storage container 20.
【0045】かかる押圧手段50は、水平方向載荷装置
51を構成するシリンダー51aに水平方向に連結され
たシャフト52の先端側に供試体押圧板53を設けて、
シャフト52をガイドベアリング52aに水平方向にガ
イドさせながら、前後に移動できるようになっている。The pressing means 50 is provided with a test piece pressing plate 53 on the tip side of a shaft 52 connected to a cylinder 51a constituting a horizontal loading device 51 in a horizontal direction.
The shaft 52 can be moved back and forth while being guided horizontally by a guide bearing 52a.
【0046】かかる前後移動は、水平方向載荷装置51
を構成するシリンダー51aを、図中に示した両方の矢
印a、bの何れかの方向に油圧をかけながら前後移動さ
せられるようになっている。このようにして、押圧手段
50により、供試体の側面の水平方向から応力をかけら
れるようになっている。The forward and backward movement is performed by the horizontal loading device 51.
Can be moved back and forth while applying hydraulic pressure in either direction of both arrows a and b shown in the figure. In this way, the pressing means 50 can apply a stress from the horizontal direction of the side surface of the specimen.
【0047】本実施の形態では、供試体押圧板53はそ
の背面側が、シャフト52の先端側に直接設けた支持板
53aに平面的に支持されて、供試体押圧板53の背面
側から力が加わっても、シャフト52の先端側で供試体
押圧板53がふらつかずに、シャフト52から加えられ
た力が減ずることなく供試体押圧板53側に伝えられる
ように構成されている。In this embodiment, the back side of the specimen pressing plate 53 is planarly supported by a support plate 53a provided directly on the tip side of the shaft 52, and a force is applied from the back side of the specimen pressing plate 53. Even if it is applied, the specimen pressing plate 53 does not fluctuate on the distal end side of the shaft 52, and the force applied from the shaft 52 is transmitted to the specimen pressing plate 53 without being reduced.
【0048】また、本実施の形態では、供試体押圧板5
3の端面側にグリースなどを適量塗っておいて、作動時
の摺動が円滑に行えるようになっている。本実施の形態
では、以下特段説明しなくてもかかるグリースなどを摺
動部に塗って円滑な摺動が適宜に確保できるようにして
いる。In this embodiment, the specimen pressing plate 5
An appropriate amount of grease or the like is applied to the end face side of No. 3 so that sliding during operation can be performed smoothly. In the present embodiment, such a grease or the like is applied to the sliding portion so that smooth sliding can be appropriately secured without special description.
【0049】さらに、本実施の形態では、シャフト52
と水平方向載荷装置51との間に、ロードセル40a、
変位計40bが、計測手段40として設けられている。
かかる変位計40bには、ダイヤルゲージなどを使用す
ればよい。Further, in the present embodiment, the shaft 52
Between the load cell 40a and the horizontal loading device 51,
The displacement gauge 40b is provided as the measuring means 40.
A dial gauge or the like may be used for the displacement meter 40b.
【0050】開口部24bの大きさは、供試体押圧板5
3を側板23b内側にいっぱいに引くことができるよう
に、支持板53aが通せる程度の大きさに開口させてお
けばよい。The size of the opening 24b is determined by the test piece pressing plate 5
In order that the support plate 53a can pass through the inside of the side plate 23b, the support plate 53a may be opened to a size large enough to pass through.
【0051】また、環境条件設定容器10の円筒側面に
は、変位拘束手段30と同様に、上記シャフト52が周
囲を水密性にシールされた状態で、環境条件設定容器1
0内に向けて出入りできるように挿通させられている。
上記ガイドベアリング52aは、シャフト52が挿通す
る円筒側面外側に設けられている。Similarly to the displacement restraining means 30, the environmental condition setting container 1 is provided on the cylindrical side surface of the environmental condition setting container 10 with the shaft 52 being sealed in a watertight manner around the shaft 52.
It is inserted so that it can enter and exit inside 0.
The guide bearing 52a is provided on the outside of the side surface of the cylinder through which the shaft 52 is inserted.
【0052】また、環境条件設定容器10の円筒側面の
底部側には、図1に示すように、吸気口13が開口させ
られている。Further, as shown in FIG. 1, an intake port 13 is opened at the bottom of the cylindrical side surface of the environmental condition setting container 10.
【0053】吸気口13は、円筒側面外側に向けて接続
用ノズル13aが突設させられ、接続用ノズル13aと
熱風発生機(図示せず)とが、断熱型フレキシブルパイ
プ14で接続されて、熱風を環境条件設定容器10内に
送り込むことができるようになっている。The intake port 13 has a connection nozzle 13a protruding toward the outside of the cylindrical side surface, and the connection nozzle 13a and a hot air generator (not shown) are connected by a heat-insulating flexible pipe 14, Hot air can be sent into the environmental condition setting container 10.
【0054】さらに、接続用ノズル13aの開口端面
は、後記するように、熱風発生機からの熱風の送風を止
めて環境条件設定容器10内に水を入れるときには、蓋
15で適宜塞ぐことができるようになっている。Further, the opening end face of the connection nozzle 13a can be appropriately closed by the lid 15 when the supply of hot air from the hot air generator is stopped and water is poured into the environmental condition setting container 10, as described later. It has become.
【0055】また、環境条件設定容器10の上方の円形
開口部は、図1に示すように、蓋16で塞ぐことができ
るようになっている。蓋16には、温度センサー差し込
み孔が設けられ、環境条件設定容器10内の温度が温度
センサーTで管理させられるようになっている。温度セ
ンサーTを、上記熱風発生機と接続しておき、所定温度
で熱風を送ることができるようにすればよい。The circular opening above the environmental condition setting container 10 can be closed by a lid 16 as shown in FIG. The lid 16 is provided with a temperature sensor insertion hole so that the temperature inside the environmental condition setting container 10 can be managed by the temperature sensor T. The temperature sensor T may be connected to the hot air generator so that hot air can be sent at a predetermined temperature.
【0056】また、吸気口13から見て斜め上方側に当
たる位置には排気口17が開けられ、その排気口17の
直上に小型の排気ファン18が設けられている。吸気口
13から送り込まれた熱風は、排気ファン18に引かれ
るようにして、環境条件設定容器10内を通過して、排
気口17から排出させられるようになっている。An exhaust port 17 is opened at a position obliquely above the intake port 13, and a small exhaust fan 18 is provided immediately above the exhaust port 17. The hot air sent from the intake port 13 is drawn by the exhaust fan 18, passes through the environmental condition setting container 10, and is discharged from the exhaust port 17.
【0057】さらに、蓋16の中央位置には、環境条件
設定容器10内に設置した供試体格納容器20の上面側
から鉛直下方に向けて供試体に応力を加えられるよう
に、押圧手段60用の開口部16aが設けられている。Further, the pressing means 60 is provided at the center position of the lid 16 so that stress can be applied to the specimen vertically downward from the upper surface side of the specimen storage container 20 installed in the environmental condition setting container 10. Opening 16a is provided.
【0058】押圧手段60は、上方の載荷フレーム61
に鉛直下方に向けて降ろされたシャフト62の先端側
に、供試体押圧板63が取り付けられて構成されてい
る。シャフト62と載荷フレーム61との間には、ロー
ドセル40aおよび変位計40bが計測手段40として
介在させられている。The pressing means 60 includes an upper loading frame 61
A specimen pressing plate 63 is attached to the distal end of a shaft 62 that is lowered vertically downward. A load cell 40 a and a displacement meter 40 b are interposed as measuring means 40 between the shaft 62 and the loading frame 61.
【0059】シャフト62は、蓋16の中央位置に設け
られた開口部に、ガイドベアリンク62aの突設下端側
62bを差し込んで固定ができるようになっている。The shaft 62 can be fixed by inserting the projecting lower end 62b of the guide bear link 62a into an opening provided at the center of the lid 16.
【0060】供試体押圧板63は、肉厚に形成されその
背面側には、上記シャフト62の先端が取り付けられる
ようになっている。供試体押圧板63には、底面63a
側と面一になるように、多孔質部材64aが設けられて
いる。さらに、多孔質部材64aの背面側に通ずるよう
に供試体押圧板63には孔64bがあけられて、内外連
通部64が構成されている。The specimen pressing plate 63 is formed to have a large thickness, and the front end of the shaft 62 is attached to the back side thereof. The specimen pressing plate 63 has a bottom surface 63a.
A porous member 64a is provided so as to be flush with the side. Further, a hole 64b is formed in the specimen pressing plate 63 so as to communicate with the back side of the porous member 64a, and an inner / outer communicating portion 64 is formed.
【0061】このようにして、本せん断強度試練装置で
は、供試体格納容器20内の供試体の側面水平方向の中
間主応力(σ2 )を0にして(変位を拘束して)、押圧
手段50、押圧手段60をそれぞれ独立に作動させて供
試体に応力を加えることができる。As described above, in the present shear strength testing apparatus, the intermediate principal stress (σ 2 ) in the horizontal direction of the side surface of the specimen in the specimen storage container 20 is set to 0 (constraining the displacement), and the pressing means The stress can be applied to the specimen by operating the pressing means 60 and the pressing means 60 independently.
【0062】すなわち、鉛直下方に向けて押圧手段60
により最大主応力(σ1 )を、水平方向に対して押圧手
段50により最小主応力(σ3 )を加えることができる
ようになっている。That is, the pressing means 60 is directed vertically downward.
Accordingly, the maximum principal stress (σ 1 ) can be applied by the pressing means 50 in the horizontal direction, and the minimum principal stress (σ 3 ) can be applied in the horizontal direction.
【0063】さらに、供試体には、熱風による乾燥、水
没による湿潤の乾湿繰り返しを行うことによりスレーキ
ングを発生させて、その条件下で、1軸方向を拘束した
平面ひずみせん断試験を行うことができる。Further, the specimen is repeatedly dried and wet by hot air and wet and immersed by submersion to generate slaking, and under this condition, a plane strain shear test in which the uniaxial direction is constrained can be performed. .
【0064】(実施の形態2)本実施の形態では、上記
せん断試験装置を使用して平面ひずみせん断試験を行う
方法について説明する。(Embodiment 2) In this embodiment, a method of performing a plane strain shear test using the above-described shear test apparatus will be described.
【0065】平面ひずみせん断試験を行うには、先ず、
略円筒形状の環境条件設定容器10内に供試体格納容器
20を設置する。設置に際しては、環境条件設定容器1
0内の底部11に設けた底部21の周囲に、側板23
a、23a’23b、23b’を、それぞれ上記実施の
形態1で説明した要領でネジ止めし、上部が開いた状態
に供試体格納容器20を箱型に組み立てる。To conduct a plane strain shear test, first,
The specimen storage container 20 is set in the substantially cylindrical environmental condition setting container 10. At the time of installation, environmental condition setting container 1
0, a side plate 23 is provided around a bottom 21 provided on the bottom 11.
a, 23a ', 23b and 23b' are screwed in the same manner as described in the first embodiment, and the specimen storage container 20 is assembled in a box shape with the upper part opened.
【0066】さらに、供試体格納容器20の組立に際し
ては、併せて、供試体格納容器20の側面側からの押圧
手段50、変位拘束手段30も取り付けて組み立ててお
く。供試体格納容器20内で、押圧可能に供試体押圧板
53が前後に移動できるように、水平方向載荷装置51
とシャフト52とを連結しておく。同様に、変位拘束装
置31のシャフト32と供試体拘束板33とを連結して
おく。Further, when assembling the specimen storage container 20, the pressing means 50 and the displacement restraining means 30 from the side of the specimen storage container 20 are also attached. In the specimen storage container 20, the horizontal loading device 51 is moved so that the specimen pressing plate 53 can be pushed back and forth.
And the shaft 52 are connected. Similarly, the shaft 32 of the displacement restricting device 31 and the specimen restricting plate 33 are connected.
【0067】このようにして供試体格納容器20を組み
立てた後、この供試体格納容器20内に盛土材料などの
土質調査試料を入れる。土質調査試料をさらに、供試体
格納容器20内で締固める。After assembling the specimen storage container 20 in this way, a soil investigation sample such as an embankment material is put in the specimen storage container 20. The soil investigation sample is further compacted in the specimen storage container 20.
【0068】締固めに際しては、ランマーやダンパーな
どの締固め機械を使用して行えばよい。また、土質調査
試料は、供試体格納容器20内に複数回に分けて入れ、
入れる都度締固めするようにする。所定締固め度あるい
は所定密度になるまで、締固めを行う。なお、締固めに
際しては、供試体格納容器20を構成する内壁面にはグ
リースなどを薄く塗っておくとよい。For compaction, a compaction machine such as a rammer or a damper may be used. Also, the soil investigation sample is put into the specimen storage container 20 in a plurality of times,
Make sure to compact each time. Compaction is performed until a predetermined compaction degree or a predetermined density is reached. At the time of compaction, it is preferable that the inner wall surface of the specimen storage container 20 be thinly coated with grease or the like.
【0069】このようにして供試体格納容器20内に締
固めによる供試体を作製したのち、供試体格納容器20
の上方側に押圧手段60を組み立てる。供試体格納容器
20内の供試体の上に供試体押圧板63を載せ、その状
態で供試体押圧板63の背面側に、載荷フレーム61に
鉛直下方に向けて接続させたシャフト62の先端側を取
り付ける。なお、載荷フレーム61とシャフト62との
間には、図1に示すように、計測手段40としてロード
セル40a、変位計40bを介在させる。After the specimens are compacted in the specimen storage container 20 in this way, the specimen storage containers 20
The pressing means 60 is assembled on the upper side of. The specimen pressing plate 63 is placed on the specimen in the specimen storage container 20, and in this state, the tip side of the shaft 62 connected to the loading frame 61 vertically downward on the back side of the specimen pressing plate 63. Attach. As shown in FIG. 1, a load cell 40a and a displacement meter 40b are interposed between the loading frame 61 and the shaft 62 as the measuring means 40.
【0070】このように供試体格納容器20を、その押
圧手段50、60、および変位拘束手段30とともに組
み立てた後、実際の測定地盤環境などに合わせて、図4
に示すように、変位拘束手段30の供試体拘束板33を
固定する(ε2 =0)。併せて、押圧手段50により最
小主応力(σ3 )を加えるとともに、押圧手段60によ
り最大主応力(σ1 )を供試体に加える。After assembling the specimen storage container 20 together with the pressing means 50 and 60 and the displacement restraining means 30 as described above, the specimen storage container 20 is adapted to the actual measurement ground environment and the like as shown in FIG.
As shown in ( 2 ), the specimen restraint plate 33 of the displacement restraint means 30 is fixed (ε 2 = 0). At the same time, the pressing means 50 applies the minimum principal stress (σ 3 ) and the pressing means 60 applies the maximum principal stress (σ 1 ) to the specimen.
【0071】供試体に作用する荷重を、変位拘束手段3
0、押圧手段50、60に連動させたロードセル40a
で測定するとともに、変位を押圧手段50、60に連動
させた変位計40bで測定する。このようにして、測定
条件に合わせた応力を供試体に加える。The load acting on the specimen is applied to the displacement restraining means 3.
0, load cell 40a linked to pressing means 50, 60
And the displacement is measured by a displacement meter 40b linked to the pressing means 50 and 60. In this way, a stress according to the measurement conditions is applied to the specimen.
【0072】この状態で、供試体格納容器20を内部に
配置した環境条件設定容器10の吸気口13に、熱風発
生機(図示せず)の吹出口側を断熱型フレキシブルパイ
プ14で連結して、環境条件設定容器10内に所定温度
の熱風を送る。In this state, the air outlet 13 of the hot air generator (not shown) is connected to the air inlet 13 of the environmental condition setting container 10 in which the specimen storage container 20 is disposed by the heat insulating flexible pipe 14. Then, hot air of a predetermined temperature is sent into the environmental condition setting container 10.
【0073】所定温度の熱風を所定時間環境条件設定容
器10内に送ることにより、環境条件設定容器10内は
乾燥環境下に置かれる。これにより、環境条件設定容器
10内に置かれた供試体格納容器20内の供試体は、内
外連通部22、64を通して熱風に接触し、供試体中の
水分が除かれ乾燥させられる。By sending hot air of a predetermined temperature into the environment condition setting container 10 for a predetermined time, the environment condition setting container 10 is placed in a dry environment. As a result, the specimen in the specimen storage container 20 placed in the environmental condition setting container 10 comes into contact with the hot air through the inside / outside communication portions 22 and 64, and the moisture in the specimen is removed and dried.
【0074】この状態を一定時間続けて供試体を乾燥さ
せた後、熱風発生機を接続用ノズル13aから外して、
代わりに蓋15で塞ぐ。After the specimen was dried in this state for a certain period of time, the hot air generator was removed from the connection nozzle 13a.
Instead, cover with lid 15.
【0075】その後、給・排水口12の管接続口12a
に給水管(図示せず)を接続して、環境条件設定容器1
0内に水を入れる。水は、供試体格納容器20が水没す
る程度に入れればよい。供試体格納容器20の水没状態
を一定時間続けることにより、内外連通部22、64を
介して、環境条件設定容器10内の水没環境(加湿環
境)を供試体に及ぼすことができる。このようにして、
供試体が湿潤状態になるまで水没させておき、その後、
給・排水口12から水を排出する。Thereafter, the pipe connection port 12a of the water supply / drain port 12
A water supply pipe (not shown) is connected to the
Pour water into 0. The water may be introduced to such an extent that the specimen storage container 20 is submerged. By continuing the submerged state of the specimen storage container 20 for a certain period of time, the submerged environment (humidified environment) in the environmental condition setting container 10 can be exerted on the specimen through the internal and external communication portions 22 and 64. In this way,
Submerge the specimen until it becomes wet, then
The water is discharged from the water supply / drain opening 12.
【0076】上記要領で熱風を送る乾燥手段と、水没さ
せる加湿手段とを交互に繰り返すことにより、供試体に
乾湿繰り返しを行わせスレーキングを発生させる。By alternately repeating the drying means for sending hot air and the humidifying means for submersion in the above-described manner, the test specimen is repeatedly dried and wet to generate slaking.
【0077】この乾湿繰り返しを行うそれぞれの段階で
は、最大主応力(σ1 )、最小主応力(σ3 )を一定に
保った状態で、ロードセル40a、変位計40bの計測
手段40で、互いに直交する押圧手段方向の変形量と、
変位拘束手段方向(中間主応力(σ2 )方向)の荷重を
測定する。At each stage of the repetition of the wet and dry operation, the load cell 40a and the measuring means 40 of the displacement meter 40b mutually intersect at right angles while the maximum principal stress (σ 1 ) and the minimum principal stress (σ 3 ) are kept constant. The amount of deformation in the direction of the pressing means,
The load in the direction of the displacement restraining means (the direction of the intermediate principal stress (σ 2 )) is measured.
【0078】また、最小主応力(σ3 )を一定に保った
まま、押圧手段60により、最大主応力(σ1 )である
鉛直荷重のみを増加させて、供試体を破壊させて平面ひ
ずみ圧縮試験を行うことができる。Further, while the minimum principal stress (σ 3 ) is kept constant, only the vertical load, which is the maximum principal stress (σ 1 ), is increased by the pressing means 60 to destroy the specimen and compress the plane strain. Testing can be performed.
【0079】併せて、このせん断中の最小主応力
(σ3 )を一定に保ったまま、最大主応力(σ1 )方向
の荷重と、最大・最小主応力(σ1 、σ3 )の各方向の
供試体の変形量と、中間主応力(σ2 )方向の荷重を測
定する。At the same time, while the minimum principal stress (σ 3 ) during the shearing is kept constant, the load in the maximum principal stress (σ 1 ) direction and the maximum / minimum principal stress (σ 1 , σ 3 ) The amount of deformation of the specimen in the direction and the load in the direction of the intermediate principal stress (σ 2 ) are measured.
【0080】さらに、供試体の最小主応力(σ3 )を、
3〜4種類代えて、同様の試験を実施する。各最小主応
力(σ3 )において求められた応力〜ひずみ曲線を、変
形解析に使用することができる。Further, the minimum principal stress (σ 3 ) of the specimen is
A similar test is performed instead of three or four types. The stress-strain curve determined at each minimum principal stress (σ 3 ) can be used for deformation analysis.
【0081】あるいは、各最小主応力(σ3 )における
最大偏差応力(σ3 ・σ3 )max を、Mohrの応力円
表示をして、これらの応力円を直線近似して強度パラメ
ーター(粘着力と内部摩擦角)などを求めることができ
る。Alternatively, the maximum deviation stress (σ 3 · σ 3 ) max at each minimum principal stress (σ 3 ) is expressed as a Mohr stress circle, and these stress circles are linearly approximated to obtain a strength parameter (adhesive strength). And internal friction angle).
【0082】(実施の形態3)上記実施の形態1では、
せん断強度試験装置は、図1に示すように、直交する3
軸方向のうち1軸方向の変位を拘束した平面ひずみせん
断強度試験装置に構成したが、この変位拘束手段30の
代わりに、押圧手段70を設けた構成も考えられる。(Embodiment 3) In Embodiment 1 described above,
As shown in FIG.
Although the apparatus is configured as a plane strain shear strength test apparatus in which displacement in one axial direction is restricted, a configuration in which a pressing means 70 is provided instead of the displacement restricting means 30 is also conceivable.
【0083】かかるせん断強度試験装置は、図5に示す
ように、油圧で作動するシリンダー71に、ロードセル
40a、変位計40bを介在させてシャフト72を水平
方向に押圧可能に設けられている。シャフト72は、ガ
イドベアリング72aでガイドされ、シャフト72の先
端側には供試体押圧板73が、支持板73aを介して設
けられている。As shown in FIG. 5, such a shear strength test apparatus is provided so that a shaft 72 can be pressed in a horizontal direction with a load cell 40a and a displacement meter 40b interposed in a hydraulically operated cylinder 71. The shaft 72 is guided by a guide bearing 72a, and a test piece pressing plate 73 is provided on the tip side of the shaft 72 via a support plate 73a.
【0084】さらに、供試体押圧板73は、供試体押圧
板53より小さく構成され、押圧手段70により加えら
れる主応力(σ2 )の方が、押圧手段50により加えら
れる応力(σ3 )より大きくなるように構成されてい
る。The specimen pressing plate 73 is smaller than the specimen pressing plate 53, and the main stress (σ 2 ) applied by the pressing means 70 is smaller than the stress (σ 3 ) applied by the pressing means 50. It is configured to be large.
【0085】このように構成したせん断強度試験装置を
使用することにより、主応力σ1 >σ2 >σ3 となる3
主応力試験(3軸せん断強度試験)を行うことができ
る。By using the shear strength test apparatus thus configured, the principal stress σ 1 > σ 2 > σ 3 is satisfied.
A main stress test (triaxial shear strength test) can be performed.
【0086】特に、上記実施の形態1、3において、押
圧手段50、60、70、および変位拘束手段30は、
環境条件設定容器10、供試体格納容器20に適宜組立
機能に構成されているので、適宜に平面せん断強度試験
装置として、あるいは3主応力試験装置として切り替え
ることが容易にできる。In particular, in the first and third embodiments, the pressing means 50, 60, 70 and the displacement restraining means 30
Since the assembling function is appropriately configured in the environmental condition setting container 10 and the specimen storage container 20, it can be easily switched to a plane shear strength test device or a three principal stress test device as appropriate.
【0087】さらに、実施の形態1で述べたせん断試験
装置の構成で、押圧手段50を変位拘束手段30で代え
れば、圧縮沈下試験用の装置として構成することもでき
る。Further, in the configuration of the shear test apparatus described in the first embodiment, if the pressing means 50 is replaced by the displacement restraining means 30, the apparatus can be configured as a compression settling test apparatus.
【0088】以上、本発明者によってなされた発明を実
施の形態に基づき具体的に説明したが、本発明は前記の
形態に限定されるものではなく、その要旨を逸脱しない
範囲で種々変更可能であることはいうまでもない。Although the invention made by the inventor has been specifically described based on the embodiment, the invention is not limited to the above-described embodiment and can be variously modified without departing from the gist of the invention. Needless to say, there is.
【0089】[0089]
【発明の効果】本願において開示される発明のうち、代
表的なものによって得られる効果を簡単に説明すれば、
以下のとおりである。Advantageous effects obtained by typical ones of the inventions disclosed in the present application will be briefly described.
It is as follows.
【0090】(1).本発明の構成では、泥岩や頁岩、
凝灰岩、砂岩などの軟岩類からなる盛土材料を締固めて
作製した供試体に、供試体格納容器内で最大主応力(σ
1 )と最小主応力(σ3 )をそれぞれに独立に加えられ
るので、盛土造成により生じた斜面内の応力状態や盛土
地盤内の高い土被り圧状態の再現ができる状態でせん断
強度試験を行うことができる。(1). In the configuration of the present invention, mudstone, shale,
The maximum principal stress (σ) in the specimen containment vessel was prepared by compacting the embankment material consisting of soft rocks such as tuff and sandstone.
1 ) and the minimum principal stress (σ 3 ) can be applied independently to each other, so the shear strength test is performed in a state that can reproduce the stress state on the slope caused by embankment creation and the high overburden pressure state in the embankment. be able to.
【0091】(2).本発明の構成では、乾燥環境と加
湿環境とが交互に設定できる環境条件設定容器内に、内
外連通部を設けた供試体格納容器を設置するようになっ
ているので、供試体に乾湿繰り返しを行ってスレーキン
グを発生させることができる。(2). In the configuration of the present invention, the specimen storage container provided with the internal / external communication part is installed in the environment condition setting container in which the drying environment and the humidifying environment can be set alternately. To generate slaking.
【0092】(3).乾燥手段として、容器内に熱風発
生機により所定の温度の熱風をある一定時間送って乾燥
させる手段を採用し、加湿手段として、容器内に給水し
て供試体格納容器を水没させる手段としたので、簡単な
構成でスレーキングを発生させることができる。(3). As a drying means, a means for sending hot air of a predetermined temperature by a hot air generator into a container for drying for a certain period of time is employed, and as a humidifying means, a means for supplying water into the container and submerging the specimen storage container is adopted. Slaking can be generated with a simple configuration.
【0093】(4).本発明の構成では、押圧手段を設
けた供試体格納容器内に供試体を入れた状態でスレーキ
ングを発生させているので、供試体にスレーキングを発
生させた後引き続いて供試体の最大主応力のみを増加さ
せるなどして、供試体を別の容器などに入れ換えずにス
レーキング状態での土の強度試験を行うことができる。(4). In the configuration of the present invention, since the slaking is generated in a state where the specimen is placed in the specimen storage container provided with the pressing means, only the maximum main stress of the specimen is continuously generated after the slaking is generated in the specimen. For example, the soil strength test in the slaking state can be performed without replacing the specimen with another container or the like by increasing the number of samples.
【0094】(5).このため、スレーキングが発生し
やすい軟岩材料による盛土斜面の安定性の評価や、盛土
地盤の沈下予測を正確に行うことができる。(5). For this reason, it is possible to accurately evaluate the stability of the embankment slope by soft rock material in which slaking is likely to occur, and accurately predict settlement of the embankment.
【0095】(6).本発明のせん断強度試験装置で
は、供試体を中間主応力(σ2 )方向の変位を拘束(ε
2 =0)した状態で、最大主応力(σ1 )、最小主応力
(σ3 )をそれぞれ独立に加えて行うので、より原位置
の条件に近い平面ひずみ圧縮状態での試験ができる。(6). In the shear strength test apparatus of the present invention, the specimen is restrained from displacement in the direction of the intermediate principal stress (σ 2 ) (ε
(2 = 0), the maximum principal stress (σ 1 ) and the minimum principal stress (σ 3 ) are independently applied, so that the test can be performed in a plane strain compression state closer to the condition of the original position.
【0096】(7).本発明のせん断強度試験装置で
は、中間主応力方向の変位拘束手段に代えて、押圧手段
を設けることができるので、最大・中間・最小主応力
(σ1 、σ2 、σ3 )を、それぞれ独立に制御した3主
応力試験(σ1 >σ2 >σ3 )が可能である。(7). In the shear strength test apparatus of the present invention, since the pressing means can be provided instead of the displacement restraining means in the intermediate main stress direction, the maximum, intermediate, and minimum main stresses (σ 1 , σ 2 , σ 3 ) are respectively determined. Independently controlled three principal stress tests (σ 1 > σ 2 > σ 3 ) are possible.
【0097】(8).本発明のせん断強度試験装置で
は、中間主応力(σ2 )と最小主応力(σ3 )の水平2
方向の各変位を拘束して、最大主応力(σ1 )のみを加
えた試験をすれば、通常の圧縮沈下試験も可能である。(8). In the shear strength test apparatus according to the present invention, the horizontal two of the intermediate principal stress (σ 2 ) and the minimum principal stress (σ 3 )
If a test in which only the maximum principal stress (σ 1 ) is applied while restraining each displacement in the direction is performed, a normal compression settlement test is also possible.
【図1】本発明のせん断強度試験装置の断面図である。FIG. 1 is a sectional view of a shear strength test apparatus according to the present invention.
【図2】本発明のせん断強度試験装置の平断面図であ
る。FIG. 2 is a plan sectional view of the shear strength test apparatus of the present invention.
【図3】本実施の形態の側板同士の連結状況を示す要部
断面図である。FIG. 3 is a cross-sectional view of a main part showing a connection state between side plates according to the present embodiment.
【図4】供試体に加える応力方向を示す説明図である。FIG. 4 is an explanatory view showing the direction of stress applied to a specimen.
【図5】本発明の3軸せん断強度試験が行えるせん断強
度試験装置の平断面図である。FIG. 5 is a plan cross-sectional view of a shear strength test apparatus capable of performing a triaxial shear strength test according to the present invention.
10 環境条件設定容器 11 底部 12 給・排水口 12a 管接続口 13 吸気口 13a 接続用ノズル 14 断熱型フレキシブルパイプ 15 蓋 16 蓋 16a 開口部 17 排気口 18 排気ファン 20 供試体格納容器 21 底部 22 内外連通部 22a 多孔質部材 22b 貫通孔 23a 側板 23a’側板 23b 側板 23b’側板 24a 側板 24b 開口部 30 変位拘束手段 31 変位拘束装置 32 シャフト 32a ガイドベアリング 33 供試体拘束板 33a 支持板 40 計測手段 40a ロードセル 40b 変位計 50 押圧手段 51 水平方向載荷装置 52 シャフト 52a ガイドベアリング 53 供試体押圧板 53a 支持板 60 押圧手段 61 載荷フレーム 62 シャフト 62a ガイドベアリング 63 供試体押圧板 64 内外連通部 64a 多孔質部材 64b 孔 70 押圧手段 71 載荷装置 72 シャフト 72a ガイドベアリング 73 供試体押圧板 73a 支持板 DESCRIPTION OF SYMBOLS 10 Environmental condition setting container 11 Bottom part 12 Supply / drain port 12a Pipe connection port 13 Intake port 13a Connection nozzle 14 Insulated flexible pipe 15 Lid 16 Lid 16a Opening 17 Exhaust port 18 Exhaust fan 20 Specimen storage container 21 Bottom 22 Inside and outside Communication part 22a Porous member 22b Through hole 23a Side plate 23a 'Side plate 23b Side plate 23b' Side plate 24a Side plate 24b Opening 30 Displacement restraint means 31 Displacement restraint device 32 Shaft 32a Guide bearing 33 Specimen restraint plate 33a Support plate 40 Measurement means 40a Load cell 40b Displacement gauge 50 Pressing means 51 Horizontal loading device 52 Shaft 52a Guide bearing 53 Specimen pressing plate 53a Support plate 60 Pressing means 61 Loading frame 62 Shaft 62a Guide bearing 63 Specimen pressing plate 64 Passing portion 64a Porous member 64b Hole 70 Pressing means 71 Loading device 72 Shaft 72a Guide bearing 73 Specimen pressing plate 73a Support plate
Claims (5)
度試験を行うせん断強度試験装置であって、 押圧手段により内部の土質調査試料の供試体に互いに直
交する3軸方向からそれぞれ独立して応力を与える供試
体格納容器と、 乾燥手段と加湿手段との両手段により、内部に設置した
前記供試体格納容器を乾燥環境下と加湿環境下とに交互
に置くことができる環境条件設定容器とを有し、 前記環境条件設定容器内に設置した前記供試体格納容器
に、前記環境条件設定容器内の環境条件を前記供試体格
納容器内の前記供試体に及ぼすための内外連通部を設け
るとともに、 前記押圧手段に計測手段を連動させて設けたことを特徴
とするせん断強度試験装置。1. A shear strength test device for performing a shear strength test of soil under conditions of occurrence of slaking, wherein a stress is independently applied to a sample of an internal soil investigation sample from three axial directions orthogonal to each other by a pressing means. A storage container to be provided, and an environment condition setting container capable of alternately placing the storage container installed therein in a dry environment and a humid environment by both drying means and humidifying means. The specimen storage container installed in the environment condition setting container, and an internal / external communication part for providing an environmental condition in the environmental condition setting container to the test object in the specimen storage container is provided, A shear strength test apparatus characterized in that a measuring means is provided in conjunction with a pressing means.
って、 前記乾燥手段とは、前記環境条件設定容器内に熱風を通
して、前記環境条件設定容器内に設置した前記供試体格
納容器を乾燥環境下に置く手段であり、 前記乾燥環境下に置かれた前記供試体格納容器内の前記
供試体が、前記内外連通部を介して乾燥状態にさせら
れ、 前記加湿手段とは、前記環境条件設定容器内に前記供試
体格納容器が水没するまで水を入れて、前記供試体格納
容器を加湿環境下に置く手段であり、 前記加湿環境下に置かれた前記供試体格納容器内の前記
供試体が、前記内外連通部を介して湿潤状態にさせられ
ることを特徴とするせん断強度試験装置。2. The shear strength test apparatus according to claim 1, wherein the drying means passes hot air through the environmental condition setting container to dry the specimen storage container installed in the environmental condition setting container. Means for placing in an environment, wherein the specimen in the specimen storage container placed in the dry environment is made to be in a dry state through the inside / outside communication part, and the humidifying means is the environmental condition Means for pouring water into the setting container until the specimen storage container is submerged, and placing the specimen storage container in a humidified environment, wherein the specimen in the specimen storage container placed in the humidified environment is A shear strength test apparatus wherein a specimen is brought into a wet state via the inside / outside communication part.
装置であって、 前記押圧手段のうち、互いに直交する水平2方向の押圧
手段の一方を、変位拘束手段に代えたことを特徴とする
せん断強度試験装置。3. The shear strength test apparatus according to claim 1, wherein one of the pressing means in two horizontal directions orthogonal to each other is replaced with a displacement restraining means. Shear strength test equipment.
度試験を行うせん断強度試験方法であって、 互いに直交する3軸方向からそれぞれ独立して押圧可能
な供試体格納容器内に、土質調査試料を入れて締固めて
供試体とする工程と、 前記3軸方向から前記供試体に測定条件に合わせて押圧
して応力を加える工程と、 前記供試体を、乾燥状態と湿潤状態とに交互に置いて、
前記供試体にスレーキングを発生させる工程と、 スレーキング発生状態での前記供試体に、前記押圧手段
により応力を加えて前記供試体をせん断破壊させて3軸
せん断強度を求める工程とを有するせん断強度試験方
法。4. A shear strength test method for performing a shear strength test of soil under conditions of occurrence of slaking, wherein a soil investigation sample is placed in a specimen storage container that can be pressed independently from three axes perpendicular to each other. Inserting and compacting the specimen, applying a stress by pressing the specimen from the three axial directions according to the measurement conditions, and alternately placing the specimen in a dry state and a wet state hand,
A shear strength test comprising: a step of generating slaking on the specimen; and a step of applying a stress to the specimen in a state where the slaking occurs by the pressing means to cause the specimen to shear and break to obtain triaxial shear strength. Method.
度測定を行うせん断強度試験方法であって、 互いに直交する3軸方向のうち水平2方向の一方を変位
拘束手段で拘束可能とするとともに、他の2軸方向から
押圧手段でそれぞれ独立して押圧可能な供試体格納容器
内に、土質調査試料を入れて締固めにより供試体とする
工程と、 前記2軸方向から前記供試体に測定条件に合わせて押圧
して応力を加える工程と、 前記供試体を、乾燥状態と湿潤状態とに交互に置いて、
前記供試体にスレーキングを発生させる工程と、 スレーキング発生状態での前記供試体に、前記押圧手段
により応力を加えて前記供試体をせん断破壊させて平面
ひずみせん断強度を求める工程とを有するせん断強度試
験方法。5. A shear strength test method for measuring shear strength of soil under conditions of occurrence of slaking, wherein one of two horizontal directions among three axial directions orthogonal to each other can be restrained by displacement restraining means. A step of putting a soil investigation sample into a specimen storage container which can be independently pressed by a pressing means from two axial directions to form a specimen by compaction, and measuring conditions for the specimen from the two axial directions. Applying a stress by pressing together, the test specimen, alternately placed in a dry state and a wet state,
A shear strength test comprising: a step of generating slaking on the test specimen; and a step of applying a stress to the test specimen in the state of occurrence of slaking to cause the test specimen to shear and break to obtain plane strain shear strength. Method.
Priority Applications (1)
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JP22526097A JPH1164202A (en) | 1997-08-21 | 1997-08-21 | Method and device for testing shear strength |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
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JP22526097A JPH1164202A (en) | 1997-08-21 | 1997-08-21 | Method and device for testing shear strength |
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ID=16826536
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1997
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