JP2003294601A - Indoor shear testing apparatus for brittle rock - Google Patents
Indoor shear testing apparatus for brittle rockInfo
- Publication number
- JP2003294601A JP2003294601A JP2002133341A JP2002133341A JP2003294601A JP 2003294601 A JP2003294601 A JP 2003294601A JP 2002133341 A JP2002133341 A JP 2002133341A JP 2002133341 A JP2002133341 A JP 2002133341A JP 2003294601 A JP2003294601 A JP 2003294601A
- Authority
- JP
- Japan
- Prior art keywords
- shear
- rock
- test
- sample
- shear box
- 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
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
Description
【発明の詳細な説明】
【０００１】
【発明の属する技術分野】この発明は、これまで不可能
であった断層破砕帯、クリープ破砕帯等の幅の狭い脆弱
岩盤の力学特性を正確に測定することが可能な室内試験
機に関するものである。
【０００２】
【従来の技術】従来岩盤の力学特性値は原位置大型せん
断試験、室内せん断試験、室内三軸圧縮試験により求め
られている。しかし断層破砕帯、クリープ破砕帯等の幅
の狭い脆弱岩盤の力学特性は、これらのうち原位置大型
せん断試験では分布面積が極端に狭いため、室内せん断
試験および室内三軸圧縮試験では試料を試験機に合わせ
て正確に整形することができないため不可能であった。
【０００３】
【発明が解決しようとする課題】断層破砕帯等狭い場所
に分布する脆弱岩盤の力学特性値を、正確に測定するこ
と。
【０００４】
【課題を解決するための手段】狭い場所に分布する脆弱
岩盤に対してせん断試験を実施する方法には、小さな原
位置せん断試験機を開発して原位置せん断試験を実施す
るか、対象脆弱岩盤からブロックサンプリングして、そ
の試料に対し室内せん断試験を実施する方法がある。前
者の小型原位置せん断試験は、脆弱帯の幅が極端に狭い
場合は試験が困難となる。また試験面およびその周辺岩
盤の整形、試験機の設置に時間がかかりコストが高い試
験となる。しかし後者の室内試験は、脆弱岩盤の特性す
なわち精密な試料整形は不能であるが荒削りの簡易な整
形はできるという特性を利用し、簡易整形試料を対象と
した試験機を開発すれば、コストが低い正確なせん断試
験が可能となる。荒削りの整形試料でせん断試験を可能
にするために、次の手段を用いる。試験機内に試料と固
定材（石膏等）による人口岩盤を作り、固結後試料部分
をせん断箱の大きさで上に凸の形状に簡易整形をする。
この簡易整形試料の上に金属製せん断箱をかぶせ、試料
との空間をせん断箱上部のグラウト孔から石膏等でグラ
ウトする。この際せん断箱と試料の隙間からグラウト材
がもれないように、その隙間は粘土でふさぐ。グラウト
材が固結後、このせん断箱に対し鉛直およびせん断荷重
用の載荷装置および変位計測装置を設置し、せんだん試
験を実施する
【以上図１】。載荷装置は鉛直加重用とせん断加重用
（水平から１５度方向）小型油圧シリンダーから、変位
計測装置は水平変位用変位計と鉛直変位用変位計および
各油圧ジャッキに取り付けた応力計から成り、大型原位
置せん断試験機と同じ機能を有するものである
【図１】
【図３】。原理は原位置ブロックせん断試験と同じであ
る。なお力学特性を求めるには、鉛直応力を変えて４個
以上のせん断試験を必要とするが、試験試料は同時に４
個を固定し、載荷装置を各試料位置に移動設置すること
により、短時間の間に試験を実施できるようにした
【図２】。また断層破砕帯等には硬質な岩片が含まれる
ため、せん断箱の大きさに整形不能のものがあるが、こ
の場合はせん断箱より小さく整形し、試験後にせん断面
の面積を測定し、面積補正をすれば良い。この際試験面
以外でせん断箱内の部分とせん断箱に注入するグラウト
材とが付着するのを防ぐため、両者の縁を粘土等で切る
必要がある。
【０００５】
【発明の実施の形態】本試験機による試験は、基本的に
は原位置大型せん断試験（ブロックせん断試験）を小型
化した試験である。従って発明の実施形態は，原位置大
型せん断試験（ブロックせん断試験）と類似し，これを
小型化し室内で実施する形態である。
【０００６】
【実施例】脆弱岩盤から試料をブロックでサンプリング
し、室内でせん断箱の大きさに合わせて粗整形し、試験
機の試料固定部に石膏で４試料同時に固定する。固定面
から突き出した試料をナイフ等によりせん断箱がかぶさ
る大きさに、かつ上に凸の形状に荒整形する。これにせ
ん断箱をかぶせ、注入材（石膏等）が漏れないようにせ
ん断箱と試料との隙間に粘土を貼り付ける。せん断箱上
部の注入孔から注入材を注入し、せん断ブロックを作成
する
【図１】。このせん断ブロック上に載荷装置ならびに計
測装置を取り付け、せん断試験を実施する。１試料に対
し試験が終了したら、載荷装置を移動設置し、残り３試
料に対し順次試験を実施する
【図２】。
【０００７】
【発明の効果】この試験機を用いれば、これまで不可能
であった狭い範囲に分布する脆弱岩盤の物性値を、正確
にかつ経済的に求めることができる。この結果断層破砕
帯等の脆弱岩盤近辺に建設する構造物の経済設計・経済
施工、および出来上がった構造物の安定確保が可能とな
る。Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention accurately measures mechanical properties of a fragile rock having a narrow width such as a fault crush zone, a creep crush zone, etc., which has been impossible so far. The present invention relates to an indoor test machine capable of performing the test. 2. Description of the Related Art Conventionally, mechanical property values of rock mass have been obtained by an in-situ large shear test, an indoor shear test, and an indoor triaxial compression test. However, the mechanical properties of narrow fragile rocks such as fault crush zones and creep crush zones have extremely narrow distribution areas in large-scale in-situ shear tests, so specimens are tested in laboratory shear tests and indoor triaxial compression tests. This was not possible because it could not be accurately shaped to fit the machine. An object of the present invention is to accurately measure mechanical characteristic values of fragile rock distributed in a narrow place such as a fault crush zone. [0004] A method for conducting a shear test on a fragile rock mass distributed in a narrow place includes developing a small in-situ shear tester and conducting an in-situ shear test. There is a method in which block sampling is performed from a target fragile rock mass and a laboratory shear test is performed on the sample. The former small in-situ shear test becomes difficult when the width of the fragile zone is extremely narrow. In addition, shaping of the test surface and its surrounding rock and installation of the test machine require time and cost. However, in the latter laboratory test, the cost of developing a testing machine for simple shaped samples was developed by utilizing the characteristics of fragile rock, that is, the characteristics that precise sample shaping is impossible but that simple shaping of rough cutting is possible. Low accurate shear test is possible. The following means are used to enable shear tests on rough-cut shaped samples. An artificial bedrock made of a sample and a fixing material (eg, gypsum) is created in the tester, and after consolidation, the sample portion is simply shaped into an upwardly convex shape with the size of a shear box.
A metal shear box is placed over the simple shaped sample, and the space between the sample and the sample is grouted with plaster or the like from the grout hole at the top of the shear box. At this time, the gap is closed with clay so that no grout material leaks from the gap between the shear box and the sample. After the grout material has consolidated, a loading device and a displacement measuring device for vertical and shear loads are installed in this shear box, and a tendon test is performed [Fig. 1]. The loading device consists of a small hydraulic cylinder for vertical and shear loading (15 degrees from horizontal), and the displacement measuring device consists of a horizontal displacement displacement meter, a vertical displacement displacement meter, and a stress gauge attached to each hydraulic jack. It has the same function as the in-situ shear tester [FIG. 1] FIG. The principle is the same as the in-situ block shear test. In order to determine the mechanical properties, four or more shear tests are required while changing the vertical stress.
The test can be carried out in a short time by fixing the pieces and moving and installing the loading device at each sample position [FIG. 2]. In addition, some fault crush zones contain hard rock fragments, so the size of the shear box cannot be shaped.In this case, the shear box is shaped smaller than the shear box, and the area of the shear surface is measured after the test. What is necessary is just to make correction. At this time, in order to prevent the portion inside the shear box other than the test surface from adhering to the grout material to be injected into the shear box, the edges of both must be cut with clay or the like. [0005] The test using the present test machine is basically a test in which the in-situ large shear test (block shear test) is reduced in size. Therefore, the embodiment of the invention is similar to the in-situ large-scale shear test (block shear test), and is an embodiment in which the size is reduced and implemented indoors. A sample is sampled from a fragile bedrock with a block, roughly shaped in a room according to the size of a shear box, and four samples are simultaneously fixed to a sample fixing portion of a testing machine with gypsum. The sample protruding from the fixed surface is roughly shaped into a size that can be covered with a shear box by a knife or the like, and into an upwardly convex shape. This is covered with a shear box, and clay is attached to the gap between the shear box and the sample so that the injected material (eg, gypsum) does not leak. Injecting material is injected from the injection hole at the top of the shear box to create a shear block [Figure 1]. A loading device and a measuring device are mounted on the shear block, and a shear test is performed. When the test is completed for one sample, the loading device is moved and installed, and the test is performed for the remaining three samples sequentially [Fig. [0007] The use of this tester makes it possible to accurately and economically determine the physical property values of fragile rock distributed in a narrow range which has been impossible so far. As a result, it is possible to economically design and economically construct a structure to be constructed in the vicinity of a fragile rock such as a fault crush zone, and secure the stability of the completed structure.
【図面の簡単な説明】
【図１】本考案の断面図である。
【符号の説明】
１は試料、２は試料固定材、３はせん断箱、４は注入
材、５は載荷装置、６は上載圧負荷油圧シリンダー、７
はせん断力負荷油圧シリンダー、８は試料固定部、９は
水平変位変位計、１０は鉛直変位変位計、１１はせん断
力による変形時の上載圧による抵抗をなくすためのロー
ラーである。
【図２】本考案の平面図である。
【符号の説明】
１は試料固定部、２は載荷装置、３は上載圧負荷油圧シ
リンダー、４は、せん断力負荷油圧シリンダー、５はせ
ん断箱、６は試料固定材、７はグラウト孔、８は鉛直変
位測定孔である。
【図３】本考案の計測系統図である。BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a sectional view of the present invention. [Description of Signs] 1 is a sample, 2 is a sample fixing material, 3 is a shearing box, 4 is an injection material, 5 is a loading device, 6 is an overload hydraulic cylinder, 7
Denotes a hydraulic cylinder for applying a shear force, 8 denotes a sample fixing portion, 9 denotes a horizontal displacement displacement meter, 10 denotes a vertical displacement displacement meter, and 11 denotes a roller for eliminating resistance due to an overload when deformed by a shear force. FIG. 2 is a plan view of the present invention. [Description of Signs] 1 is a sample fixing unit, 2 is a loading device, 3 is an overloading pressure hydraulic cylinder, 4 is a shearing force hydraulic cylinder, 5 is a shear box, 6 is a sample fixing material, 7 is a grout hole, 8 Is a vertical displacement measurement hole. FIG. 3 is a measurement system diagram of the present invention.
─────────────────────────────────────────────────────
【手続補正書】
【提出日】平成１４年６月１９日（２００２．６．１
９）
【手続補正２】
【補正対象書類名】明細書
【補正対象項目名】特許請求の範囲
【補正方法】変更
【補正内容】
【特許請求の範囲】
【請求項１】 断層破砕帯、クリープ破砕帯等の幅の
狭い脆弱岩盤の力学特性を正確に測定することが可能な
室内せん断試験機。────────────────────────────────────────────────── ───
[Procedure amendment] [Submission date] June 19, 2002 (2002.6.1
9) [Procedure amendment 2] [Document name to be amended] Description [Item name to be amended] Claims [Amendment method] Change [Contents of amendment] [Claims] [Claim 1] Fault crush zone, creep An indoor shear tester that can accurately measure the mechanical properties of fragile rock with a narrow width, such as shatter zones.
───────────────────────────────────────────────────── フロントページの続き Ｆターム(参考） 2G061 AA11 AB01 BA04 CA06 CB03 CC01 DA01 EA01 EA02 EB03 ────────────────────────────────────────────────── ─── Continuation of front page F term (reference) 2G061 AA11 AB01 BA04 CA06 CB03 CC01 DA01 EA01 EA02 EB03
Claims (1)
狭い脆弱岩盤の力学特性を正確に測定することが可能な
室内せん断試験機。2. An indoor shear tester capable of accurately measuring mechanical properties of a fragile rock mass having a small width, such as a fault crush zone and a creep crush zone.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002133341A JP2003294601A (en) | 2002-04-01 | 2002-04-01 | Indoor shear testing apparatus for brittle rock |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP2002133341A JP2003294601A (en) | 2002-04-01 | 2002-04-01 | Indoor shear testing apparatus for brittle rock |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JP2003294601A true JP2003294601A (en) | 2003-10-15 |
Family
ID=29244126
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP2002133341A Pending JP2003294601A (en) | 2002-04-01 | 2002-04-01 | Indoor shear testing apparatus for brittle rock |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2003294601A (en) |
Cited By (19)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100337107C (en) * | 2005-05-11 | 2007-09-12 | 中国矿业大学 | Testing method of polyphase coupling creep of fragmented rock body and equipment thereof |
| CN102419303A (en) * | 2011-08-15 | 2012-04-18 | 山东科技大学 | Crack grouting visualization tester under complex conditions |
| CN103728243A (en) * | 2014-01-24 | 2014-04-16 | 河南理工大学 | Testing method of hole reinforcing material for grout injection hole of breaking roof of coal mine |
| CN103776696A (en) * | 2014-03-03 | 2014-05-07 | 中国科学院地质与地球物理研究所 | Drawing and shear testing device for geosynthetics |
| CN104316379A (en) * | 2014-10-30 | 2015-01-28 | 东北石油大学 | Cutting working table for preparing low-strength rock sample containing weak interface |
| CN106092695A (en) * | 2016-08-05 | 2016-11-09 | 湖南科技大学 | A kind of rock-like materials structural plane is produced and for the device and method of shearing test |
| CN107179391A (en) * | 2017-06-02 | 2017-09-19 | 同济大学 | A kind of experimental rig that Under-cross tunnel shallow layer grouting is buried for an ultra shallow |
| CN107907402A (en) * | 2017-11-09 | 2018-04-13 | 北京科技大学 | Chamber palisades are crisp to cut transition type crash simulation instrument |
| CN109342230A (en) * | 2018-08-27 | 2019-02-15 | 青岛理工大学 | Rock mass shear strength testing device and method based on osmotic pressure simulation |
| CN109342274A (en) * | 2018-11-29 | 2019-02-15 | 郑州大学 | High polymer crack grouting model test apparatus and test method under pressure-bearing river channels |
| CN109655336A (en) * | 2018-12-10 | 2019-04-19 | 三峡大学 | A method of research complex condition ground Creep Rule |
| CN110006758A (en) * | 2019-04-08 | 2019-07-12 | 山东科技大学 | Angle and the adjustable normal fault simulation test device of crack starter location and application method |
| CN110749513A (en) * | 2019-11-20 | 2020-02-04 | 清华大学 | Direct shear test device for rock fracture |
| CN111735724A (en) * | 2020-06-23 | 2020-10-02 | 三峡大学 | Device and method for detecting creep stress of in-situ rock-soil body |
| CN112362479A (en) * | 2021-01-14 | 2021-02-12 | 中国科学院地质与地球物理研究所 | Experimental system and method for simulating influence of fracture stick-slip dislocation on tunnel engineering |
| CN112649282A (en) * | 2020-12-30 | 2021-04-13 | 中国科学院武汉岩土力学研究所 | Method for inducing fault/crack activation under simulated stress disturbance condition |
| CN113029797A (en) * | 2021-03-15 | 2021-06-25 | 河海大学 | Rock hydraulic coupling creep test equipment |
| CN113484163A (en) * | 2021-07-02 | 2021-10-08 | 河南城建学院 | Device and method for testing rheological relaxation coupling impact disturbance of multilayer material shearing |
| WO2023165043A1 (en) * | 2022-03-04 | 2023-09-07 | 山东科技大学 | Grouting and water plugging device and test method for fractured rock in mine coupling state |
-
2002
- 2002-04-01 JP JP2002133341A patent/JP2003294601A/en active Pending
Cited By (29)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN100337107C (en) * | 2005-05-11 | 2007-09-12 | 中国矿业大学 | Testing method of polyphase coupling creep of fragmented rock body and equipment thereof |
| CN102419303A (en) * | 2011-08-15 | 2012-04-18 | 山东科技大学 | Crack grouting visualization tester under complex conditions |
| CN103728243A (en) * | 2014-01-24 | 2014-04-16 | 河南理工大学 | Testing method of hole reinforcing material for grout injection hole of breaking roof of coal mine |
| CN103776696A (en) * | 2014-03-03 | 2014-05-07 | 中国科学院地质与地球物理研究所 | Drawing and shear testing device for geosynthetics |
| CN104316379A (en) * | 2014-10-30 | 2015-01-28 | 东北石油大学 | Cutting working table for preparing low-strength rock sample containing weak interface |
| CN106092695B (en) * | 2016-08-05 | 2018-12-28 | 湖南科技大学 | A kind of rock-like materials structural plane is produced and is used for the device and method of shearing test |
| CN106092695A (en) * | 2016-08-05 | 2016-11-09 | 湖南科技大学 | A kind of rock-like materials structural plane is produced and for the device and method of shearing test |
| CN107179391A (en) * | 2017-06-02 | 2017-09-19 | 同济大学 | A kind of experimental rig that Under-cross tunnel shallow layer grouting is buried for an ultra shallow |
| CN107907402B (en) * | 2017-11-09 | 2020-08-11 | 北京科技大学 | Brittle-shear transition type destruction simulator for chamber rock wall |
| CN107907402A (en) * | 2017-11-09 | 2018-04-13 | 北京科技大学 | Chamber palisades are crisp to cut transition type crash simulation instrument |
| CN109342230A (en) * | 2018-08-27 | 2019-02-15 | 青岛理工大学 | Rock mass shear strength testing device and method based on osmotic pressure simulation |
| CN109342274A (en) * | 2018-11-29 | 2019-02-15 | 郑州大学 | High polymer crack grouting model test apparatus and test method under pressure-bearing river channels |
| CN109342274B (en) * | 2018-11-29 | 2023-09-05 | 郑州大学 | Polymer fracture grouting model test device and test method under pressure-bearing dynamic water condition |
| CN109655336B (en) * | 2018-12-10 | 2021-07-23 | 三峡大学 | Method for researching creep law of rock and soil under complex condition |
| CN109655336A (en) * | 2018-12-10 | 2019-04-19 | 三峡大学 | A method of research complex condition ground Creep Rule |
| CN110006758A (en) * | 2019-04-08 | 2019-07-12 | 山东科技大学 | Angle and the adjustable normal fault simulation test device of crack starter location and application method |
| WO2020206760A1 (en) * | 2019-04-08 | 2020-10-15 | 山东科技大学 | Forward fault simulation test apparatus having adjustable angle and initiation position, and usage method therefor |
| CN110749513A (en) * | 2019-11-20 | 2020-02-04 | 清华大学 | Direct shear test device for rock fracture |
| CN111735724B (en) * | 2020-06-23 | 2023-03-10 | 三峡大学 | Device and method for detecting creep stress of in-situ rock-soil body |
| CN111735724A (en) * | 2020-06-23 | 2020-10-02 | 三峡大学 | Device and method for detecting creep stress of in-situ rock-soil body |
| CN112649282A (en) * | 2020-12-30 | 2021-04-13 | 中国科学院武汉岩土力学研究所 | Method for inducing fault/crack activation under simulated stress disturbance condition |
| CN112362479B (en) * | 2021-01-14 | 2021-04-02 | 中国科学院地质与地球物理研究所 | Experimental system and method for simulating influence of fracture stick-slip dislocation on tunnel engineering |
| US11085859B1 (en) | 2021-01-14 | 2021-08-10 | Institute Of Geology And Geophysics, Chinese Academy Of Sciences | Experimental system and method for simulating effect of fault stick-slip displacement on tunnel engineering |
| CN112362479A (en) * | 2021-01-14 | 2021-02-12 | 中国科学院地质与地球物理研究所 | Experimental system and method for simulating influence of fracture stick-slip dislocation on tunnel engineering |
| CN113029797A (en) * | 2021-03-15 | 2021-06-25 | 河海大学 | Rock hydraulic coupling creep test equipment |
| CN113484163A (en) * | 2021-07-02 | 2021-10-08 | 河南城建学院 | Device and method for testing rheological relaxation coupling impact disturbance of multilayer material shearing |
| CN113484163B (en) * | 2021-07-02 | 2023-08-11 | 河南城建学院 | Rheological relaxation coupling impact disturbance testing device and method for multilayer material shearing |
| WO2023165043A1 (en) * | 2022-03-04 | 2023-09-07 | 山东科技大学 | Grouting and water plugging device and test method for fractured rock in mine coupling state |
| US11906481B1 (en) | 2022-03-04 | 2024-02-20 | Shandong University Of Science And Technology | Grouting and water-plugging device for fractured rock in mine coupling state, and test method |
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