JPH05215746A - Triaxial piping test device for undisturbed sample and test method - Google Patents
Triaxial piping test device for undisturbed sample and test methodInfo
- Publication number
- JPH05215746A JPH05215746A JP1751092A JP1751092A JPH05215746A JP H05215746 A JPH05215746 A JP H05215746A JP 1751092 A JP1751092 A JP 1751092A JP 1751092 A JP1751092 A JP 1751092A JP H05215746 A JPH05215746 A JP H05215746A
- Authority
- JP
- Japan
- Prior art keywords
- pressure
- specimen
- water
- test
- piping
- 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.)
- Granted
Links
- 238000012360 testing method Methods 0.000 title claims abstract description 53
- 238000010998 test method Methods 0.000 title claims abstract description 9
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 54
- 238000009835 boiling Methods 0.000 claims abstract description 18
- 125000006850 spacer group Chemical group 0.000 claims abstract description 12
- 229920001971 elastomer Polymers 0.000 claims abstract description 6
- 239000007788 liquid Substances 0.000 claims description 16
- NJPPVKZQTLUDBO-UHFFFAOYSA-N novaluron Chemical compound C1=C(Cl)C(OC(F)(F)C(OC(F)(F)F)F)=CC=C1NC(=O)NC(=O)C1=C(F)C=CC=C1F NJPPVKZQTLUDBO-UHFFFAOYSA-N 0.000 claims description 14
- 230000002093 peripheral effect Effects 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 8
- 238000011065 in-situ storage Methods 0.000 claims description 3
- 229920006395 saturated elastomer Polymers 0.000 claims 1
- 238000007789 sealing Methods 0.000 claims 1
- 239000002689 soil Substances 0.000 abstract description 9
- 230000035699 permeability Effects 0.000 abstract description 3
- 239000004575 stone Substances 0.000 description 6
- 238000011160 research Methods 0.000 description 5
- 230000000452 restraining effect Effects 0.000 description 4
- 238000005070 sampling Methods 0.000 description 3
- 239000004925 Acrylic resin Substances 0.000 description 1
- 229920000178 Acrylic resin Polymers 0.000 description 1
- 230000002528 anti-freeze Effects 0.000 description 1
- 230000004323 axial length Effects 0.000 description 1
- 238000012790 confirmation Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 239000012780 transparent material Substances 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
Landscapes
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】この発明は、実地盤の土の透水性
能（パイピング特性又はボイリング特性）を把握、確認
するために実施されるパイピング（及びボイリングを含
む、以下同じ）試験装置と試験方法に係り、さらに云え
ば、実地盤から乱されない不攪乱試料を採取して実地盤
に等しい三軸応力状態の下で行なわれる三軸型パイピン
グ試験装置及び試験方法に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piping (and including boiling, the same applies hereinafter) testing apparatus and a testing method for grasping and confirming the water permeability (piping characteristic or boiling characteristic) of soil in the actual ground. More particularly, the present invention relates to a triaxial piping test apparatus and a test method for collecting an undisturbed sample from the actual ground and performing it under a triaxial stress condition equal to that of the actual ground.
【０００２】[0002]
【従来の技術】実地盤の土のパイピング特性又はボイリ
ング特性を把握、確認することは、例えばダム建設に当
り、ダムサイトの地盤調査項目として重要である。その
試験方法を大別すると、供試体を人工的に作る場合
と、実地盤から不攪乱試料を採取して供試体を作る場
合とがある。また、応力状態については、非三軸タイ
プと、できるだけ実地盤に近い三軸応力状態で試験す
る場合、とがある。2. Description of the Related Art It is important as a ground survey item for a dam site, for example, when constructing a dam to grasp and confirm the piping property or the boiling property of soil on the actual ground. The test methods can be broadly divided into cases in which the test piece is artificially made, and cases in which an undisturbed sample is taken from the actual ground to make the test piece. Regarding the stress state, there are a non-triaxial type and a case where the test is performed in a triaxial stress state as close to actual ground as possible.
【０００３】上記の供試体を人工的に作る場合、及び
同の実地盤とは応力状態が全く相関のない非三軸タイ
プ試験の結果は、実地盤の性状に即したものとは云え
ず、原位置の土の透水性能を正確に把握し得ない。次
に、上記、に該当する従来の三軸型パイピング試験
方法及び装置は、図４に例示したように、圧力容器（セ
ル）１内でペデスタル２とトップキャップ３とにより供
試体４の上下端が挟持され、ピストン５がトップキャッ
プ３を介して供試体４に実地盤の上載圧を加える。圧力
容器１内に満たされたセル液を加圧して、供試体４の周
側面に任意の拘束圧が加えられる。供試体４の下端とペ
デスタル２との間に介在させたポーラスストーン２５を
通じて供試体４に給水管６が接続され、また、供試体４
の上端とトップキャップ３との間に介在させたポーラス
ストーン５を通じて供試体４に排水管７が接続されてい
る。圧力容器１内のセル液の圧力は、側圧制御装置８で
調整される。The results of a non-triaxial type test in which the above-mentioned specimens are artificially produced and in which the stress state has no correlation with the actual ground, cannot be said to be in accordance with the properties of the actual ground. It is not possible to accurately grasp the permeability of soil in situ. Next, as shown in FIG. 4, the conventional three-axis type piping test method and apparatus corresponding to the above, the upper and lower ends of the specimen 4 by the pedestal 2 and the top cap 3 in the pressure vessel (cell) 1. Are clamped, and the piston 5 applies the top loading pressure of the actual ground to the sample 4 via the top cap 3. The cell liquid filled in the pressure vessel 1 is pressurized to apply an arbitrary restraining pressure to the peripheral side surface of the sample 4. The water supply pipe 6 is connected to the sample 4 through a porous stone 25 interposed between the lower end of the sample 4 and the pedestal 2, and the sample 4
A drain pipe 7 is connected to the specimen 4 through a porous stone 5 interposed between the upper end of the and the top cap 3. The pressure of the cell liquid in the pressure vessel 1 is adjusted by the lateral pressure control device 8.
【０００４】上述した従来の試験装置によれば、供試体
４にピストン５を通じて所定大きさの上載圧を加え、側
圧制御装置８によって供試体４の周側面に所定大きさの
拘束圧を加えた上で、給水管６を通じて供給する水と、
排水管７を通じて排除する水とに、水中の気泡を消して
供試体４の飽和度を１００％近くまで上げるバックプレ
ッシャーＨ0 と、パイピング試験に必要な大きさの水頭
差Ｈ1 とを設定し、水みちが発生するパイピング及びボ
イリングの発生水圧を確認する試験が行なわれる。According to the above-described conventional testing apparatus, a predetermined amount of top loading pressure is applied to the test piece 4 through the piston 5, and a lateral pressure control device 8 applies a predetermined amount of restraining pressure to the peripheral side surface of the test piece 4. Above, with the water supplied through the water supply pipe 6,
For the water to be removed through the drainage pipe 7, a back pressure H 0 that eliminates air bubbles in the water to raise the saturation of the sample 4 to nearly 100% and a head difference H 1 of a magnitude necessary for the piping test are set. A test is carried out to confirm the water pressure generated by piping and boiling that generate water flow.
【０００５】[0005]
【本発明が解決しようとする課題】図４に示した従来の
三軸型パイピング試験方法及び装置は、ピストン５によ
る上載圧、及びセル液による供試体周側面への拘束圧を
加えた三軸応力状態を実現するが、この応力状態は厳密
には等方応力状態を実現するにすぎない。とりわけ供試
体周側面の拘束圧は、側方向ひずみを拘束する大きさの
圧力を加える、所謂Ｋ0 状態にはなっていないので、実
地盤の応力状態の下でのパイピング試験とは言えず、試
験結果の精度、信頼性に問題がある。The conventional three-axis type piping test method and apparatus shown in FIG. 4 is a three-axis type in which an upper mounting pressure by the piston 5 and a restraining pressure on the peripheral side surface of the sample by the cell liquid are applied. A stress state is realized, but strictly speaking, this stress state only realizes an isotropic stress state. In particular, the restraining pressure on the side surface of the specimen is not in the so-called K 0 state in which a pressure of a magnitude that restrains the lateral strain is applied, so it cannot be said to be a piping test under the stress state of the actual ground, There is a problem in the accuracy and reliability of test results.
【０００６】また、供試体４の上端は、ポーラスストー
ン２５を介して直接トップキャップ３と全面的に接触し
て上載圧を受ける構造なので、パイピングやボイリング
の発生が機械的な力で拘束を受け、パイピング特性、ボ
イリング特性を過少評価する可能性が高いので、解決す
るべき課題になっている。Further, since the upper end of the test piece 4 is in direct contact with the top cap 3 through the porous stone 25 and receives a top mounting pressure, the occurrence of piping and boiling is restrained by mechanical force. Since there is a high possibility that the piping characteristics and the boiling characteristics will be underestimated, it is a problem to be solved.
【０００７】[0007]
【課題を解決するための手段】上述した従来技術の課題
を解決するための手段として、この発明に係る不攪乱試
料の三軸型パイピング試験装置は、図１〜図３に実施例
を示したように、三軸圧力容器の中で供試体のパイピン
グ試験を行なう試験装置において、（イ） 不攪乱試料
から作られた供試体４の上下の端部を挟むペデスタル２
とトップキャップ３が圧力容器１内の略中心部の上下に
配置され、トップキャップ３は前記供試体４に上載圧を
負荷させるピストン５に取り付けられており、ペデスタ
ル２には供試体４の下端に脱気水を供給する給水管６が
接続され、トップキャップ３には供試体４を通過してき
た水を排除する排水管７が接続され、（ロ） 前記圧力
容器１内の前記ペデスタル２とトップキャップ３とで挟
持された供試体４の外周位置に、上端が圧力容器１内上
部の加圧空間１０に開放され、内径が比較的に小さい内
セル１１が設置され、この内セル１１内に満たされ前記
供試体４を水没させるセル液１２の液面変化を計測する
水位センサー１３が設置され、（ハ） 供試体４の上端
とトップキャップ３との間に、トップキャップ３の上載
圧を供試体４に伝達するがボイリングは拘束しない構造
のスペーサ１４が介在され、（ニ） 前記給水管６を通
じて供給する脱気水と、前記排水管７を通じて排出され
る排水とに、パイピング試験に必要な大きさの水頭差Ｈ
1 とバックプレッシャーＨ0 が付与されること、をそれ
ぞれ特徴とする。As a means for solving the above-mentioned problems of the prior art, an undisturbed sample triaxial piping testing apparatus according to the present invention is shown in FIGS. 1 to 3. As described above, in the test apparatus for performing the piping test of the specimen in the triaxial pressure vessel, (a) the pedestal 2 that sandwiches the upper and lower ends of the specimen 4 made from the undisturbed sample
And a top cap 3 are arranged above and below a substantially central portion in the pressure vessel 1, the top cap 3 is attached to a piston 5 that applies a top loading pressure to the specimen 4, and the pedestal 2 has a lower end of the specimen 4. A water supply pipe 6 for supplying deaerated water is connected to the top cap 3, and a drain pipe 7 for removing water passing through the sample 4 is connected to the top cap 3, and (b) the pedestal 2 in the pressure vessel 1 and At the outer peripheral position of the sample 4 sandwiched by the top cap 3, the upper end is opened to the pressurizing space 10 in the upper part of the pressure vessel 1, and the inner cell 11 having a relatively small inner diameter is installed. The water level sensor 13 for measuring the change in the liquid level of the cell liquid 12 which is filled with the water and submerges the sample 4 is installed. (C) The top pressure of the top cap 3 is placed between the upper end of the sample 4 and the top cap 3. Transmitted to Specimen 4 However, a spacer 14 having a structure that does not restrain the boiling is interposed, and (d) the degassed water supplied through the water supply pipe 6 and the drainage discharged through the drainage pipe 7 have a head size necessary for a piping test. Difference H
1 and that back pressure H 0 is applied.
【０００８】また、第２の発明に係る不攪乱試料の三軸
型パイピング試験方法は、三軸応力が作用する条件下で
供試体のパイピング試験を行なう方法において、（ａ）
供試体４は、不攪乱試料から形成した試料ピースの外
周面にゴム膜１５を被せてシールすること、（ｂ） 前
記供試体４の軸方向の両端に原位置地盤と等しい大きさ
の上載圧を加え、周側面には側方向ひずみを拘束する大
きさの圧力を加えること、（ｃ） 供試体４に上載圧を
加える部材と供試体４の端部との間に、上載圧は伝達す
るがボイリングは拘束しない構造のスペーサ１４を介在
させること、（ｄ） 供試体４の軸方向に通過させる水
は、脱気水又は飽和度を１００％近くまで上げるための
バックプレッシャーをかけた水を使用し、該水の供給圧
力と排水圧力とにはパイピング試験に必要な大きさの水
頭差Ｈ1 が付与されること、をそれぞれ特徴とする。The triaxial piping test method for an undisturbed sample according to the second aspect of the present invention is the method of performing a piping test of a specimen under the condition that triaxial stress acts.
The test piece 4 is formed by covering the outer peripheral surface of a sample piece formed from an undisturbed sample with a rubber film 15 to seal the sample piece, and (b) an axial load of the same size as the in-situ ground at both axial ends of the test piece 4. In addition, a pressure of a magnitude that restrains the lateral strain is applied to the peripheral side surface. (C) The top loading pressure is transmitted between the member for applying the top loading pressure to the sample 4 and the end of the sample 4. However, the spacer 14 having a structure that does not restrain the boiling is interposed. (D) The water to be passed in the axial direction of the specimen 4 is deaerated water or water under back pressure for increasing the saturation to near 100%. The water supply pressure and the drainage pressure used are each provided with a head difference H 1 of a magnitude necessary for the piping test.
【０００９】[0009]
【作用】不攪乱試料から形成した供試体４を使用し、実
地盤と等しい上載圧を加え、且つ周側面には側方向ひず
みを拘束する大きさの圧力を加えてＫ0 状態とするの
で、実地盤に近い組織の土による実地盤の応力状態を再
現したパイピング試験が行なえる。The specimen 4 formed from the undisturbed sample is used, and the same mounting pressure as that of the actual ground is applied, and a pressure of a magnitude that restrains the lateral strain is applied to the peripheral side surface to bring it into the K 0 state. A piping test that reproduces the stress state of the actual ground due to the soil having a structure close to the actual ground can be performed.
【００１０】しかも、水が通過する供試体上端のパイピ
ング又はボイリングの発生は、スペーサ１４の存在によ
って拘束を受けないので、供試体４のパイピング特性あ
るいはボイリング特性を妨げられず、過少評価のおそれ
がない。Moreover, since the occurrence of piping or boiling at the upper end of the specimen through which water passes is not restricted by the presence of the spacer 14, the piping characteristic or the boiling characteristic of the specimen 4 is not hindered, and there is a risk of underestimation. Absent.
【００１１】[0011]
【実施例】次に、図１〜図３に示した本発明の実施例を
説明する。図１に示した三軸型パイピング試験装置も、
上盤１６と下盤１７及び外セルとで構成された圧力容器
１内の略中心部の上下に、供試体４の上下の端部を挟む
ペデスタル２とトップキャップ３が配置されている。ペ
デスタル２は下盤１７に固定され、トップキャップ３は
供試体４に上載圧を加えるピストン５に取付けられてい
る。ペデスタル２及びトップキャップ３は、各々ポーラ
スストーン２５を介して供試体４を挟持する構成とされ
ている。ペデスタル２には、前記ポーラスストーン２５
を介して供試体４の下端に脱気水を供給する給水管６が
接続されている。また、トップキャップ３には、前記ポ
ーラスストーン２５を通じて供試体４を軸方向に通過し
てきた水を排除する排水管７が接続されている。EXAMPLES Next, examples of the present invention shown in FIGS. 1 to 3 will be described. The triaxial piping testing device shown in FIG.
A pedestal 2 and a top cap 3 that sandwich the upper and lower end portions of the sample 4 are arranged above and below a substantially central portion in a pressure vessel 1 configured by an upper plate 16, a lower plate 17, and an outer cell. The pedestal 2 is fixed to the lower plate 17, and the top cap 3 is attached to a piston 5 that applies an overloading pressure to the sample 4. The pedestal 2 and the top cap 3 are each configured to sandwich the sample 4 via a porous stone 25. The pedestal 2 has 25 porous stones.
A water supply pipe 6 for supplying degassed water is connected to the lower end of the specimen 4 via. Further, the top cap 3 is connected to a drain pipe 7 that removes water that has axially passed through the sample 4 through the porous stone 25.
【００１２】圧力容器１内において、前記ペデスタル２
及びトップキャップ３、あるいはこれらで挟持された供
試体４の外周位置に、上端が圧力容器１内の加圧空間１
０に開放され、内径が必要最小限度に小さく透明な内セ
ル１１が設置され、圧力容器１内は二重管構造に構成さ
れ、各々の室に水又は不凍液の如きセル液１２が収容さ
れている。特に、内セル１１内には、供試体４を完全に
水没させる程度の水位までセル液１２が満たされてい
る。そして、該内セル１１の上部には、図２に詳示した
ように計器ハウジング１８を設け、水位センサー１３が
設置されている。即ち、計器ハウジング１８の下底にギ
ャップセンサー１９が設置され、その真っ直ぐ上方のセ
ル液液面上にフロート２０が浮かべられ、フロート２０
の上下変位（ギャップの大小）をギャップセンサー１９
に発生する誘導電圧の変化（大きさ）としてリアルタイ
ムに電気値として計測する。In the pressure vessel 1, the pedestal 2
At the outer peripheral position of the top cap 3 or the sample 4 sandwiched by these, the pressurizing space 1 with the upper end inside the pressure vessel 1
0, the inner diameter is set to the minimum necessary and a transparent inner cell 11 is installed, the pressure vessel 1 has a double tube structure, and each chamber contains a cell liquid 12 such as water or antifreeze liquid. There is. In particular, the inner cell 11 is filled with the cell liquid 12 to a water level such that the sample 4 is completely submerged. On the upper part of the inner cell 11, as shown in detail in FIG. 2, an instrument housing 18 and a water level sensor 13 are installed. That is, the gap sensor 19 is installed on the lower bottom of the instrument housing 18, and the float 20 is floated on the liquid surface of the cell liquid directly above the gap sensor 19.
The vertical displacement (size of the gap) of the gap sensor 19
It is measured as an electric value in real time as the change (magnitude) of the induced voltage that occurs at.
【００１３】要するに、この三軸型パイピング装置は、
ピストン５により実地盤と等しい上載圧を供試体４に作
用させる。また、中央制御装置２１により調整された空
気圧２２を圧力容器１内の加圧空間１０に作用させ、ひ
いては内セル１１内のセル液１２を通じて供試体４の周
側面に側方向ひずみを拘束する大きさの圧力を作用させ
てＫ0 状態とする。つまり、供試体４の側方向ひずみの
発生を、内セル１１内のセル液１２の液面変化として水
位センサー１３で把握し、その計測値が入力された中央
制御装置２１の演算処理により加圧空間１０内の空気圧
２２の大きさを調整して実地盤の応力状態と等しいＫ0
状態が実現されるのである。In summary, this triaxial piping device is
The piston 5 exerts the same loading pressure as the actual ground on the sample 4. In addition, the air pressure 22 adjusted by the central controller 21 is applied to the pressurizing space 10 in the pressure vessel 1, and consequently the lateral strain is restrained to the peripheral side surface of the sample 4 through the cell liquid 12 in the inner cell 11. The pressure is applied to bring the state into K 0 . That is, the occurrence of the lateral strain of the sample 4 is grasped by the water level sensor 13 as a change in the liquid level of the cell liquid 12 in the inner cell 11, and the pressure is applied by the arithmetic processing of the central controller 21 to which the measured value is input. Adjusting the magnitude of the air pressure 22 in the space 10 equals the stress state of the actual ground K 0
The state is realized.
【００１４】供試体４は、不攪乱試料から作る。従来、
実地盤から乱されない不攪乱試料を採取する方法として
は、ブロックサンプリング法、チューブサンプリング
法、凍結サンプリング法などが知られ実施されている。
供試体４は、前記いずれかの方法で採取した不攪乱試料
を適当な大きさ（直径７cm、軸方向長さ１０ｍぐらい）
の円柱形ピースに切り出し、その外周面にゴム膜１５を
被せることによってシールし形成される。なお、不攪乱
試料から円柱形ピースを切り出す要領として、実地盤に
おける土層構成の境界層と並行な向きに軸線を持つ円柱
形ピースを切り出して供試体４を作ると、前記境界層に
沿うパイピング特性の試験を行なえることになって極め
て有意義である。Specimen 4 is made from an undisturbed sample. Conventionally,
Block sampling method, tube sampling method, frozen sampling method, etc. are known and practiced as a method for collecting an undisturbed sample that is not disturbed from the actual ground.
Specimen 4 has an appropriate size (diameter 7 cm, axial length 10 m) of undisturbed sample collected by any of the above methods.
It is formed by cutting it into a cylindrical piece and covering the outer peripheral surface with a rubber film 15. In addition, as a procedure for cutting a cylindrical piece from an undisturbed sample, when a cylindrical piece having an axis line in a direction parallel to the boundary layer of the soil layer structure in the actual ground is cut out to make a test piece 4, piping along the boundary layer is performed. It is extremely meaningful to be able to test the characteristics.
【００１５】本発明の場合、上記のようにして作った供
試体４は、図３に詳示したように、該供試体４の上端と
トップキャップ３との間に、トップキャップ３からの上
載圧を供試体４に伝えるが、供試体上端のパイピング又
はボイリングを妨げない、リング状のスペーサ１４を介
在させたことを特徴としている。このリング状のスペー
サ１４は、透明なアクリル樹脂で形成され、厚さを５m
m、外径は７０mm、内径が５０mmぐらいに形成されてい
る。もっとも、スペーサ１４は、前述した上載圧を伝達
し、ボイリングを妨げない構成でさえあればよいので、
井桁構造とか格子構造、又は幾重かの同心円リング構造
や格子構造のものを同様に使用可能である。In the case of the present invention, the specimen 4 produced as described above is mounted on the top cap 3 between the upper end of the specimen 4 and the top cap 3, as shown in detail in FIG. It is characterized by interposing a ring-shaped spacer 14 which transmits pressure to the specimen 4 but does not hinder piping or boiling at the upper end of the specimen. The ring-shaped spacer 14 is made of transparent acrylic resin and has a thickness of 5 m.
m, the outer diameter is 70 mm, and the inner diameter is about 50 mm. Of course, the spacer 14 need only have a structure that transmits the above-mentioned loading pressure and does not hinder the boiling.
It is likewise possible to use a double girder structure or a lattice structure, or several concentric ring structures or lattice structures.
【００１６】この三軸型パイピング試験装置は、供試体
４の上端が上記スペーサ１４を介してトップキャップ３
に挟持され、かつ上述したように実地盤応力状態に等し
い上載圧と側方向ひずみを拘束したＫ0 状態とによる三
軸応力状態を実現した上で、給水管６と排水管７との間
にパイピング試験に必要な大きさの水頭差Ｈ1 を付与し
てパイピング試験が行なわれ、パイピングあるいはボイ
リングが発生する水頭差Ｈ1 の確認が行なわれる。従っ
て、内セル１１及びゴム膜１５を透明材で形成すると、
パイピング特性あるいはボイリング特性の目視確認も容
易になる。パイピング試験に使用する水が完全な脱気水
でない場合は、前記の水頭差Ｈ1 は、水中の気泡を消し
て供試体４の飽和度を１００％近くまで上げるのに必要
なバックプレッシャーを包含した大きさとされる（図４
参照）。In this triaxial piping test apparatus, the upper end of the test piece 4 is connected to the top cap 3 via the spacer 14.
Between the water supply pipe 6 and the drain pipe 7 after realizing the triaxial stress state by the upper loading pressure equal to the actual ground stress state and the K 0 state in which the lateral strain is restrained as described above. by applying the size of the water head difference H 1 required piping test is performed piping test confirmed the water head difference H 1 to piping or boiling occurs is performed. Therefore, when the inner cell 11 and the rubber film 15 are formed of a transparent material,
Visual confirmation of piping characteristics or boiling characteristics is also facilitated. If the water used for the piping test is not completely degassed water, the water head difference H 1 includes the back pressure required to eliminate the bubbles in the water and raise the saturation of the sample 4 to nearly 100%. It is made the size (Fig. 4
reference).
【００１７】[0017]
【本発明が奏する効果】本発明に係る不攪乱試料の三軸
型パイピング試験装置及び試験方法によれば、実地盤に
即した条件下での試験が行なわれ、その試験結果を容易
に精度良く得られ、パイピング特性あるいはボイリング
特性を高い信頼性のもとに確認評価でき、地盤調査の実
効性を高らしめるのである。EFFECTS OF THE INVENTION According to the triaxial type testing apparatus and test method for undisturbed samples according to the present invention, a test is conducted under conditions suitable for actual ground, and the test results can be easily and accurately obtained. The obtained piping characteristics or boiling characteristics can be confirmed and evaluated with high reliability, and the effectiveness of the ground survey can be enhanced.
【図１】本発明に係る三軸型パイピング試験装置の全体
図である。FIG. 1 is an overall view of a triaxial piping testing device according to the present invention.
【図２】内セルの水位センサー部分を拡大して示した断
面図である。FIG. 2 is an enlarged sectional view showing a water level sensor portion of an inner cell.
【図３】供試体とスペーサ及びトップキャップの関係を
詳示した断面図である。FIG. 3 is a cross-sectional view showing in detail the relationship between the specimen, the spacer and the top cap.
【図４】従来のパイピング試験装置の全体図である。FIG. 4 is an overall view of a conventional piping test device.
４ 供試体 ２ ペデスタル ３ トップキャップ １ 圧力容器 ５ ピストン ６ 給水管 ７ 排水管 １０ 加圧空間 １１ 内セル １２ セル液 １３ 水位センサー １４ スペーサ Ｈ 水頭差 １５ ゴム膜 4 Specimen 2 Pedestal 3 Top cap 1 Pressure vessel 5 Piston 6 Water supply pipe 7 Drain pipe 10 Pressurized space 11 Inner cell 12 Cell liquid 13 Water level sensor 14 Spacer H Water head difference 15 Rubber film
───────────────────────────────────────────────────── フロントページの続き (72)発明者 森嶋 章 東京都中央区銀座八丁目21番１号 株式会 社竹中土木内 (72)発明者 高橋 三津彦 東京都中央区銀座八丁目21番１号 株式会 社竹中土木内 (72)発明者 大原 淳良 東京都目黒区東が丘二丁目11番16号 株式 会社東京ソイルリサーチ内 (72)発明者 片山 郁夫 茨城県つくば市梅園二丁目１番12号 株式 会社東京ソイルリサーチつくば事務所内 (72)発明者 南坂 貴彦 東京都目黒区東が丘二丁目11番16号 株式 会社東京ソイルリサーチ内 (72)発明者 畑中 宗憲 東京都江東区南砂二丁目５番14号 株式会 社竹中工務店技術研究所内 (72)発明者 鈴木 善雄 東京都江東区南砂二丁目５番14号 株式会 社竹中工務店技術研究所内 (72)発明者 内田 明彦 東京都江東区南砂二丁目５番14号 株式会 社竹中工務店技術研究所内 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Morishima 8-21-1, Ginza, Chuo-ku, Tokyo Stock company Takenaka Civil Engineering (72) Inventor Mitsuhiko Takahashi 8-21-1, Ginza, Chuo-ku, Tokyo Stock company Takenaka Civil Engineering (72) Inventor Atsura Ohara, 2-11-16 Higashigaoka, Meguro-ku, Tokyo Within Tokyo Soil Research Co., Ltd. (72) Inventor Ikuo Katayama 2-1-1, Umezono, Tsukuba, Ibaraki Tokyo Soil Research Tsukuba Office (72) Inventor Takahiko Minamisaka 2-11-16 Higashigaoka, Meguro-ku, Tokyo Stock Company Tokyo Soil Research (72) Inventor Munenori Hatanaka 2-5-14 Minamisuna, Koto-ku, Tokyo Stock Association Takenaka Corporation Technical Research Institute (72) Inventor Yoshio Suzuki 2-5-14 Minamisuna, Koto-ku, Tokyo Stock Company Takenaka Corporation Technology Research house (72) inventor Uchida, Akihiko, Koto-ku, Tokyo Minamisuna chome No. 5 No. 14 stock company Takenaka intra-technology Research Institute
Claims (2)
験を行なう試験装置において、（イ） 不攪乱試料から
作られた供試体の上下の端部を挟むペデスタルとトップ
キャップが圧力容器内の略中心部の上下に配置され、ト
ップキャップは前記供試体に上載圧を負荷させるピスト
ンに取り付けられており、ペデスタルには供試体の下端
に脱気水を供給する給水管が接続され、トップキャップ
には供試体を通過してきた水を排除する排水管が接続さ
れていること、（ロ） 前記圧力容器内の前記ペデスタ
ルとトップキャップとで挟持された供試体の外周位置に
は、上端が圧力容器内上部の加圧空間に開放され、且つ
内径が比較的に小さい内セルが設置され、この内セル内
に前記供試体を水没させる程度に満たされたセル液の液
面変化を計測する水位センサーが設置されていること、
（ハ） 供試体の上端とトップキャップとの間には、ト
ップキャップの上載圧を供試体に伝達するがボイリング
は拘束しない構造のスペーサが介在されていること、
（ニ） 前記給水管を通じて供給する脱気水と、前記排
水管を通じて排出される排水とには、パイピング試験に
必要な大きさの水頭差が付与されること、をそれぞれ特
徴とする、不攪乱試料の三軸型パイピング試験装置。1. A test apparatus for performing a piping test of a specimen in a triaxial pressure vessel, comprising: (a) a pedestal and a top cap sandwiching the upper and lower ends of the specimen made from an undisturbed sample inside the pressure vessel. The top cap is attached to the top and bottom of the substantially central part of the, and the top cap is attached to the piston that applies the loading pressure to the specimen, and the pedestal is connected to the water supply pipe for supplying degassed water to the lower end of the specimen, A drain pipe for removing water that has passed through the specimen is connected to the cap, (b) an upper end is provided at an outer peripheral position of the specimen sandwiched between the pedestal and the top cap in the pressure vessel. An inner cell having a relatively small inner diameter is installed in the pressurized space in the upper part of the pressure vessel, and the change in the liquid level of the cell liquid filled to the extent that the specimen is submerged in the inner cell is measured. water That the sensor is installed,
(C) Between the upper end of the test piece and the top cap, there is interposed a spacer of a structure that transmits the top loading pressure of the top cap to the test piece but does not restrain the boiler.
(D) Undisturbed water, which is characterized in that degassed water supplied through the water supply pipe and drainage discharged through the drainage pipe have a head difference of a magnitude required for a piping test. Three-axis piping tester for samples.
ピング試験を行なう方法において、（ａ） 供試体は、
不攪乱試料から形成した試料ピースの外周面にゴム膜を
被せてシールすること、（ｂ） 前記供試体の軸方向の
両端には原位置地盤と等しい大きさの上載圧を加え、周
側面には側方向ひずみを拘束する大きさの圧力を加える
こと、（ｃ） 供試体に上載圧を加える部材と供試体の
端部との間に、上載圧は伝達するがボイリングは拘束し
ない構造のスペーサを介在させること、（ｄ） 供試体
の軸方向に通過させる水は、脱気水又は飽和度を１００
％近くまで上げるためのバックプレッシャーをかけた水
を使用し、該水の供給圧力と排水圧力とにはパイピング
試験に必要な大きさの水頭差を付与すること、をそれぞ
れ特徴とする、不攪乱試料の三軸型パイピング試験方
法。2. A method for conducting a piping test of a specimen under the condition that triaxial pressure acts, wherein (a) the specimen is:
Sealing by covering the outer peripheral surface of the sample piece formed from the undisturbed sample with a rubber film, and (b) applying an upper loading pressure of the same size as the in-situ ground to both ends of the specimen in the axial direction, Is a pressure of a magnitude that restrains lateral strain. (C) A spacer with a structure that transmits the top loading pressure but does not restrain the boiling between the member that applies the top loading pressure to the specimen and the end of the specimen. (D) The water to be passed in the axial direction of the specimen should be degassed water or saturated to 100%.
%, Using water under back pressure to raise the pressure to near 100%, and providing a water head difference of a magnitude necessary for a piping test to the supply pressure and drainage pressure of the water. Test method for triaxial piping of samples.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01751092A JP3210922B2 (en) | 1992-02-03 | 1992-02-03 | Triaxial piping test apparatus and test method for undisturbed samples |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP01751092A JP3210922B2 (en) | 1992-02-03 | 1992-02-03 | Triaxial piping test apparatus and test method for undisturbed samples |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH05215746A true JPH05215746A (en) | 1993-08-24 |
| JP3210922B2 JP3210922B2 (en) | 2001-09-25 |
Family
ID=11945972
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP01751092A Expired - Fee Related JP3210922B2 (en) | 1992-02-03 | 1992-02-03 | Triaxial piping test apparatus and test method for undisturbed samples |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3210922B2 (en) |
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