JPH0459405B2 - - Google Patents
Info
- Publication number
- JPH0459405B2 JPH0459405B2 JP59270521A JP27052184A JPH0459405B2 JP H0459405 B2 JPH0459405 B2 JP H0459405B2 JP 59270521 A JP59270521 A JP 59270521A JP 27052184 A JP27052184 A JP 27052184A JP H0459405 B2 JPH0459405 B2 JP H0459405B2
- Authority
- JP
- Japan
- Prior art keywords
- pile
- perforated
- sandy ground
- piles
- ground
- 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.)
- Expired - Lifetime
Links
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 25
- 238000010276 construction Methods 0.000 claims description 12
- 238000000034 method Methods 0.000 claims description 12
- 239000004576 sand Substances 0.000 claims description 9
- 239000000463 material Substances 0.000 claims description 6
- 229910000831 Steel Inorganic materials 0.000 claims description 3
- 239000010959 steel Substances 0.000 claims description 3
- 230000000694 effects Effects 0.000 description 6
- 239000002245 particle Substances 0.000 description 5
- 239000002689 soil Substances 0.000 description 4
- 230000002265 prevention Effects 0.000 description 3
- 238000009434 installation Methods 0.000 description 2
- 230000035699 permeability Effects 0.000 description 2
- 239000004575 stone Substances 0.000 description 2
- 238000005056 compaction Methods 0.000 description 1
- 239000002131 composite material Substances 0.000 description 1
- 238000012790 confirmation Methods 0.000 description 1
- 238000007596 consolidation process Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000945 filler Substances 0.000 description 1
- 239000010419 fine particle Substances 0.000 description 1
- 238000007689 inspection Methods 0.000 description 1
- 239000007788 liquid Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 230000003014 reinforcing effect Effects 0.000 description 1
- 229920006395 saturated elastomer Polymers 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E02—HYDRAULIC ENGINEERING; FOUNDATIONS; SOIL SHIFTING
- E02D—FOUNDATIONS; EXCAVATIONS; EMBANKMENTS; UNDERGROUND OR UNDERWATER STRUCTURES
- E02D3/00—Improving or preserving soil or rock, e.g. preserving permafrost soil
- E02D3/02—Improving by compacting
- E02D3/10—Improving by compacting by watering, draining, de-aerating or blasting, e.g. by installing sand or wick drains
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は地震時に液状化の発生の可能性のある
砂質地盤の液状化防止工法に関するもので、孔あ
き杭を利用し、構造物の支持も可能としたもので
ある。[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a construction method for preventing liquefaction of sandy ground where liquefaction may occur during an earthquake. It also made support possible.
砂地盤の液状化現象は水で飽和した緩い砂地盤
が、間〓水の逃げ出しを許さない状態で地震によ
るせん断応力を受けたとき、間〓水圧が急激に増
加し、砂粒子の結合力がなくなり、砂地盤のせん
断強度が失われることに基づいている。砂地盤が
このような液状化状態になると構造物の倒壊、地
盤崩壊が引き起こされる。従つて、このような問
題を解決するため、表−１〔末松直幹・吉見吉
昭・佐々木康：地盤の液状化、7.液状化被害を軽
減するための対策、土と基礎30−４（291）、71〜
79頁〕に示されるような各種検法が採用されてい
るが、そのほとんどが地盤改良工法（密度の増
大、粒度改良または固結）であり、多大な工期、
工費を必要とするばかりか、振動締固めにも見ら
れるように振動、騒音の問題がある。
The liquefaction phenomenon of sandy ground occurs when loose sandy ground saturated with water is subjected to shear stress due to an earthquake without allowing water to escape, the water pressure increases rapidly and the bonding force of sand particles increases. This is based on the fact that the shear strength of the sandy ground is lost. When sandy ground reaches such a liquefied state, structures collapse and ground collapse occurs. Therefore, in order to solve such problems, Table 1 [Naoki Suematsu, Yoshiaki Yoshimi, Yasushi Sasaki: Liquefaction of the ground, 7. Measures to reduce liquefaction damage, soil and foundations 30-4 (291 ), 71~
Various inspection methods have been adopted, as shown in page 79], but most of them are soil improvement methods (increasing density, improving particle size, or consolidation), which require a long construction period,
Not only does it require construction costs, but it also has problems with vibration and noise, as seen in vibratory compaction.
これに対し、安価で無振動無騒音の工法とし
て、間〓水圧の消散を目的としたグラベルドレー
ン工法が提案されている。このようなグラベルド
レーン工法に関連する発明としては、例えば特開
昭55−142815号公報、特開昭56−100919号公報、
実開昭56−116434号公報等に記載されたものがあ
り、砕石、砂利等の柱を砂地盤中に多数設置し、
地震時に砂地盤に発生する過剰間〓水圧を消散さ
せることを原理としている。 In contrast, a gravel drain method has been proposed as an inexpensive, vibration-free and noise-free construction method that aims to dissipate water pressure. Inventions related to such gravel drain construction methods include, for example, JP-A-55-142815, JP-A-56-100919,
There is a method described in Japanese Utility Model Publication No. 116434/1983, etc., in which many pillars of crushed stone, gravel, etc. are installed in sandy ground.
The principle is to dissipate the excess water pressure that occurs in sandy ground during an earthquake.
しかし、上述のグラベルドレーン工法には次の
ような問題点がある。
However, the gravel drain construction method described above has the following problems.
グラベル材間に生じる間〓を排水路として過
剰間〓水圧の消散を図つているが、グラベル柱
の径に対し、グラベル材が排水路の断面を大幅
に狭めることになるとともに、グラベル材自体
が排水抵抗を与えるため、地震時の急激な過剰
間〓水圧の上昇に対しては、排水抵抗も大き
く、その分、液状化抑止効果が小さくなる。 The gap between the gravel materials is used as a drainage channel to dissipate excess water pressure, but the gravel material significantly narrows the cross section of the drainage channel relative to the diameter of the gravel pillar, and the gravel material itself Since it provides drainage resistance, the drainage resistance is also large in response to a sudden increase in excessive water pressure during an earthquake, and the liquefaction prevention effect is correspondingly reduced.
地震発生とともに、間〓水が細砂を伴つてグ
ラベル柱へ移動するため、グラベル材間の間〓
に細砂が入り込んで目詰まりを起こし、対策効
果がすぐに低下する。 When an earthquake occurs, water moves to the gravel pillars along with fine sand, causing the gaps between the gravel materials to decrease.
Fine sand gets inside and causes clogging, which quickly reduces the effectiveness of the countermeasure.
既設構造物下に設置するには、構造物を一旦
移動させることが必要で、多大の工期、工費を
要する。 In order to install it under an existing structure, it is necessary to move the structure once, which requires a large amount of construction time and construction cost.
地震等により地盤の側方流動、すべり、不等
沈下が生じた際、グラベル柱がずれて柱を形成
しなくなり、効果を失することも少なくない。 When lateral movement, sliding, or uneven subsidence of the ground occurs due to earthquakes, etc., gravel columns often shift and no longer form columns, resulting in a loss of effectiveness.
砂地盤の液状化抑止効果は認められるが、あ
くまで局所的地盤改良の範疇に属し、構造物を
支えるといつた支持機能は有していない。 Although the effect of suppressing liquefaction of sandy ground is recognized, it belongs to the category of local ground improvement and does not have the supporting function of supporting structures.
本発明の液状化防止工法は上述のような問題点
の解決を図つたものである。 The liquefaction prevention method of the present invention is intended to solve the above-mentioned problems.
本発明の砂地盤の液状化防止工法では、長手方
向及び周方向に多数の孔３を穿設してなる中空の
孔あき杭２を用いる。孔３部には砂の侵入を阻止
する通水性のあるフイルター４を設け、この孔あ
き杭２を排水材として砂地盤１の上面から所要深
さまで設置する。
In the method for preventing liquefaction of sandy ground according to the present invention, a hollow perforated pile 2 having a large number of holes 3 bored in the longitudinal direction and the circumferential direction is used. A water-permeable filter 4 for preventing sand from entering is provided in the hole 3, and the perforated pile 2 is installed as a drainage material to a required depth from the upper surface of the sandy ground 1.
このとき、好ましくは杭間ピツチＬを杭径Ｄに
対して、
2D≦Ｌ≦10D
とし、砂地盤１中に孔あき杭群を構築することに
より、地震時、砂地盤１に発生する過剰間〓水圧
を孔あき杭２内に消散させる。これにより、間〓
水圧の上昇が抑制され、砂地盤１の液状化を防止
する。すなわち、過剰間〓水圧の急激な上昇によ
り、フイルター４を通して砂地盤１から孔あき杭
２内に向けての排水が生じ、フイルター４が大部
分の砂粒子の侵入を阻止する。なお、水とともに
フイルター４を通過する細粒分については、孔あ
き杭２の上部から水とともに排出されるか、また
は中空の孔あき杭２の底部に沈澱、滞留し、孔あ
き杭内部の中空排水空間においては、管壁部の抵
抗等を除き、実質的に大きな排水抵抗を生じさせ
るものはない。 At this time, preferably the pitch L between the piles is 2D≦L≦10D with respect to the pile diameter D, and by constructing a group of perforated piles in the sandy ground 1, excessive spacing that occurs in the sandy ground 1 during an earthquake can be reduced. = Dissipate water pressure into the perforated pile 2. As a result, the interval
The increase in water pressure is suppressed, and liquefaction of the sandy ground 1 is prevented. That is, due to the sudden increase in excessive water pressure, drainage occurs from the sandy ground 1 into the perforated pile 2 through the filter 4, and the filter 4 prevents most of the sand particles from entering. The fine particles that pass through the filter 4 along with the water are either discharged from the top of the perforated pile 2 along with the water, or they settle and stay at the bottom of the hollow perforated pile 2, and are deposited in the hollow inside the perforated pile. In the drainage space, there is nothing that causes substantial drainage resistance, except for the resistance of the pipe wall.
孔あき杭２としては鋼管杭、複合パイル、その
他種々の中空杭の利用が考えられ、孔３部の断面
欠損を考慮した上で、構造物の支持杭を兼ねさせ
ることができる。 As the perforated pile 2, steel pipe piles, composite piles, and various other hollow piles can be used, and the pile can also serve as a support pile for the structure, taking into account the cross-sectional loss of the hole 3.
次に、本発明の液状化防止工法を図示した実施
例に基づいて説明する。
Next, the liquefaction prevention method of the present invention will be explained based on illustrated examples.
第２図〜第４図は本発明で使用する孔あき杭２
の一例を示したもので、孔３の部分に砂の侵入を
阻止する通水性のフイルター４を設けることで、
孔あき杭２の内部に中空の排水空間を確保してい
る。この孔あき杭２を砂地盤１中に設置し、地盤
全体の透水性を高めることにより、地盤内に発生
する過剰間〓水圧を早期に消散させ、液状化の発
生を防止するとともに、各種構造物を支持させる
ことも可能としたものである。なお、孔あき杭２
の孔３をあける位置は対象地盤の地層にもよる
が、液状化すると判定された地盤、層部に位置す
る部分にのみ孔をあけることで対処可能である。 Figures 2 to 4 show the perforated pile 2 used in the present invention.
This is an example. By installing a water-permeable filter 4 in the hole 3 to prevent sand from entering,
A hollow drainage space is secured inside the perforated pile 2. By installing these perforated piles 2 in the sandy ground 1 and increasing the water permeability of the entire ground, the excessive water pressure generated in the ground can be quickly dissipated, preventing the occurrence of liquefaction, and making it possible to improve the water permeability of the entire ground. It also made it possible to support objects. In addition, perforated pile 2
Although the position to drill the hole 3 depends on the strata of the target ground, it can be handled by drilling the hole only in the part of the ground or layer that has been determined to be liquefied.
砂地盤１への孔あき杭２設置の一例を第５図及
び第６図に示すが、平面的に見ての孔あき杭２の
効果的配置ピツチＬは、実施工での振動計測で得
られた対策効果確認結果の第９図より、
2D≦Ｌ≦10D （Ｄ：孔あき杭外径）
が適当であると考えられる。なお、孔あき杭２は
周方向に４ケ所の孔３を設け、孔３の直径ｄ＝
0.1D、長手方向の孔間隔（中心間距離）ａ＝
2.0Dとしてある（第３図参照）。また、孔３に取
り付けるフイルター４のメツシユ間隔は液状化防
止の対象とする砂地盤の平均粒径D50の約1/2以
下であれば、孔あき杭３内への砂粒子の侵入がほ
とんどない。また、杭の配置ピツチとして上記範
囲に数値限定した根拠は、第９図の縦軸で示され
る過剰間〓水圧△Ｕ／有効鉛直応力σv′が0.3以下
なら一般に液状化には到らないとされていること
によつた。ただし、重要度の低い構造物を対象と
する場合は、この範囲以上のピツチでも対応可能
と考えられる。 An example of the installation of perforated piles 2 on sandy ground 1 is shown in Figures 5 and 6, and the effective placement pitch L of perforated piles 2 in a two-dimensional view can be determined by vibration measurement during actual construction. From the results of confirmation of the effectiveness of countermeasures in Figure 9, it is considered that 2D≦L≦10D (D: outer diameter of perforated pile) is appropriate. In addition, the perforated pile 2 has four holes 3 in the circumferential direction, and the diameter d of the hole 3 is
0.1D, longitudinal hole spacing (distance between centers) a=
2.0D (see Figure 3). In addition, if the mesh spacing of the filter 4 installed in the hole 3 is approximately 1/2 or less of the average particle diameter D 50 of the sandy ground to be prevented from liquefaction, most sand particles will hardly enter into the perforated pile 3. do not have. Furthermore, the basis for restricting the pile arrangement pitch to the above range is that liquefaction generally does not occur if the excess water pressure △U/effective vertical stress σ v ', shown on the vertical axis in Figure 9, is 0.3 or less. This is because it is said to be. However, if the target is a structure of low importance, it may be possible to use a pitch larger than this range.
砂地盤１中に孔あき杭２を構築することは、地
盤中の間〓水が侵入する間〓を形成できたことに
なるので、地震時に砂地盤１中に発生する過剰間
〓水圧は上記孔あき杭２内に消散され、これによ
り砂地盤１の液状化を確実に防止し得る。 By constructing the perforated piles 2 in the sandy ground 1, it means that a gap in the ground (a gap for water to enter) can be formed, so that the excess water pressure generated in the sandy ground 1 during an earthquake is caused by the above-mentioned hole. It is dissipated into the pile 2, thereby reliably preventing liquefaction of the sandy ground 1.
なお、第５図及び第６図に示した実施例は、グ
ラベルドレーン工法でのグラベル柱の代わりに砂
地盤１にフイルター４付きの中空孔あき杭２を設
置したものに相当するが、孔あき杭２は第９図に
示したように杭間ピツチＬ／杭径Ｄ＝4.5での比
較において、グラベル柱より間〓水圧の消散効果
が大なので、杭の設置間隔をその分、広くできる
というメリツトを有している。 The embodiment shown in Figures 5 and 6 corresponds to the gravel drain construction method in which hollow perforated piles 2 with filters 4 are installed in sandy ground 1 instead of gravel pillars. As shown in Figure 9, when comparing pile pitch L/pile diameter D = 4.5, pile 2 has a greater effect of dissipating water pressure than gravel columns, so the installation interval between piles can be made wider accordingly. It has merits.
第１図は既設構造物である港湾用ケーソン６下
の砂地盤１に対して、本発明による対策を施した
例と、建物５の支持杭を兼ねされた場合の例の２
種類を示したものである。ケーソン６の例のよう
に、本発明はグラベル柱では困難な杭の斜め設置
も可能であり、構造物のリプレースなしで既設構
造物下へも設置できるというメリツトを有してい
る。 Figure 1 shows an example in which the present invention has been applied to the sandy ground 1 under the existing port caisson 6, and two examples in which the sandy ground 1 is used as a support pile for a building 5.
This shows the types. As in the example of caisson 6, the present invention has the advantage that it is possible to install piles diagonally, which is difficult with gravel columns, and that it can also be installed under existing structures without replacing the structure.
第７図及び第８図の実施例は第１図の建物５の
支持杭同様、孔あき杭２を構造物（橋脚７、貯液
状化タンク８）の支持も兼ねさせた上で、液状化
対策として用いた場合である。 The embodiment shown in FIGS. 7 and 8 is similar to the support pile of the building 5 shown in FIG. This is a case where it is used as a countermeasure.
孔あき杭、すなわち、一般の杭（鋼管杭、コン
クリート杭等）では液状化しやすい地盤において
は、地震時、杭を水平に支持する地盤の抵抗が極
めて低下するため、「道路橋示方書耐震設計編」
では液状化の程度に応じて、土質定数（変形係数
Ｅ、地盤反力係数Ｋ）を低減させるものとしてい
る。これに対し、孔あき杭２を用いると液状化の
発生を抑制できるため、土質定数の低減が必要な
くなり、その工学上のメリツト、効果は極めて大
きい。 Perforated piles, that is, ordinary piles (steel pipe piles, concrete piles, etc.), are used in ground that is prone to liquefaction, and the resistance of the ground that horizontally supports the piles is extremely low during an earthquake. "ed."
According to the degree of liquefaction, soil constants (deformation coefficient E, ground reaction force coefficient K) are supposed to be reduced. On the other hand, if the perforated pile 2 is used, the occurrence of liquefaction can be suppressed, so there is no need to reduce the soil constant, and its engineering merits and effects are extremely large.
〔発明の効果〕
孔部にフイルターを設けた中空の孔あき杭を
液状化の可能性のある砂地盤に設置すること
で、孔あき杭の断面全体を排水路として利用
し、砂地盤中に排水抵抗が非常に小さい中空の
排水路を形成することができる。[Effects of the invention] By installing a hollow perforated pile with a filter in the hole in sandy ground that is likely to liquefy, the entire cross section of the perforated pile can be used as a drainage channel, and water can be drained into the sandy ground. A hollow drainage channel with very low drainage resistance can be formed.
従つて、地震時に砂地盤に発生する過剰間〓
水圧の急激な上昇に対し、間〓水を瞬時に排水
し、地盤内の過剰間〓水圧を逸散させることが
できるため、砕石等による排水抵抗の大きいグ
ラベルドレーン工法に比べ、液状化防止効果が
大きい。 Therefore, the excess gap that occurs in sandy ground during an earthquake is
In response to a sudden increase in water pressure, the water can be instantly drained and the excess water pressure in the ground can be dissipated, making it more effective in preventing liquefaction than the gravel drain method, which has high drainage resistance due to crushed stone, etc. is large.
充填物がないため、グラベルドレーン工法で
問題視されるような目詰まりがなく、半永久的
に効果を発揮させることができる。 Since there is no filler, there is no clogging, which is a problem with the gravel drain method, and the effect can be maintained semi-permanently.
孔あき杭群は断面欠損を考慮した上で構造物
の支持にも活用でき、さらに地盤の補強にも効
果的で、杭の設置も極めて容易である。 Perforated piles can be used to support structures, taking cross-sectional defects into account, and are also effective in reinforcing the ground, and the piles are extremely easy to install.
第１図は本発明の工法の適用例を示す鉛直断面
図、第２図は孔あき杭の一例を示す斜視図、第３
図は一部を切欠いて示した正面図、第４図は水平
断面図、第５図は杭の配置を示す平面図、第６図
はその鉛直断面図、第７図及び第８図はそれぞれ
橋脚及び貯液状化タンクへの適用例を示す鉛直断
面図、第９図は従来例との比較を示すグラフであ
る。
１……砂地盤、２……孔あき杭、３……孔、４
……フイルター、５……建物、６……ケーソン、
７……橋脚、８……タンク。
Fig. 1 is a vertical sectional view showing an example of application of the construction method of the present invention, Fig. 2 is a perspective view showing an example of a perforated pile, and Fig. 3 is a perspective view showing an example of a perforated pile.
The figure is a partially cutaway front view, Figure 4 is a horizontal sectional view, Figure 5 is a plan view showing the arrangement of piles, Figure 6 is a vertical sectional view, and Figures 7 and 8 are respectively FIG. 9 is a vertical sectional view showing an example of application to a bridge pier and a liquid storage tank, and FIG. 9 is a graph showing a comparison with a conventional example. 1... Sand ground, 2... Perforated pile, 3... Hole, 4
...Filter, 5...Building, 6...Caisson,
7... Pier, 8... Tank.
Claims (1)
その孔部に砂の侵入を阻止する通水性のあるフイ
ルターを設けてなる中空の孔あき杭を、排水材と
して、砂地盤に所要の深さで多数設置し、前記各
孔あき杭内に地震時に前記砂地盤に発生する過剰
間〓水圧の上昇を抑制するための中空の排水空間
を形成したことを特徴とする砂地盤の液状化防止
工法。 ２ 孔あき杭の杭間ピツチＬは杭径Ｄに対して、 2D≦Ｌ≦10D である特許請求の範囲第１項記載の砂地盤の液状
化防止工法。 ３ 孔あき杭は構造物の荷重を支持する支持杭で
ある特許請求の範囲第１項または第２項記載の砂
地盤の液状化防止工法。 ４ 孔あき杭は多数の孔を穿設した鋼管杭である
特許請求の範囲第１項、第２項、または第３項記
載の砂地盤の液状化防止工法。[Claims] 1. A large number of holes are bored in the longitudinal direction and the circumferential direction,
A large number of hollow perforated piles with water-permeable filters installed in the holes to prevent sand from entering are installed in the sandy ground at the required depth as drainage materials, and earthquakes occur within each of the perforated piles. A construction method for preventing liquefaction of sandy ground, characterized in that a hollow drainage space is formed to suppress an increase in excessive water pressure that sometimes occurs in the sandy ground. 2. The method for preventing liquefaction of sandy ground according to claim 1, wherein the pitch L between the perforated piles is 2D≦L≦10D with respect to the pile diameter D. 3. The method for preventing liquefaction of sandy ground according to claim 1 or 2, wherein the perforated pile is a support pile that supports the load of the structure. 4. The method for preventing liquefaction of sandy ground according to claim 1, 2, or 3, wherein the perforated pile is a steel pipe pile with a large number of holes.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27052184A JPS61146910A (en) | 1984-12-21 | 1984-12-21 | Method of preventing liquefaction of sand ground |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP27052184A JPS61146910A (en) | 1984-12-21 | 1984-12-21 | Method of preventing liquefaction of sand ground |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS61146910A JPS61146910A (en) | 1986-07-04 |
| JPH0459405B2 true JPH0459405B2 (en) | 1992-09-22 |
Family
ID=17487380
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP27052184A Granted JPS61146910A (en) | 1984-12-21 | 1984-12-21 | Method of preventing liquefaction of sand ground |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS61146910A (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2564819B2 (en) * | 1987-03-24 | 1996-12-18 | 住友金属工業株式会社 | Seismic reinforcement structure of existing caisson |
| JPS6410819A (en) * | 1987-07-02 | 1989-01-13 | Nippon Kokan Kk | Steel tubular pile for preventing liquefaction of ground |
| JPH01150637U (en) * | 1988-04-07 | 1989-10-18 | ||
| JP2692193B2 (en) * | 1988-11-11 | 1997-12-17 | 住友金属工業株式会社 | Liquefaction control pile |
| JPH086337B2 (en) * | 1989-03-02 | 1996-01-24 | 株式会社フジタ | Foundation construction method and foundation pile |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5938532B2 (en) * | 1972-05-04 | 1984-09-18 | クレイトン マニフアクチユアリング コムパニ− | Automatic load control device for hydraulic rotary motion absorbers |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5162203U (en) * | 1974-11-11 | 1976-05-17 | ||
| JPS56116434U (en) * | 1980-02-07 | 1981-09-07 | ||
| JPS5938532U (en) * | 1982-09-06 | 1984-03-12 | 財団法人鉄道総合技術研究所 | Drainage pipe for pouring to prevent soil particle outflow |
-
1984
- 1984-12-21 JP JP27052184A patent/JPS61146910A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5938532B2 (en) * | 1972-05-04 | 1984-09-18 | クレイトン マニフアクチユアリング コムパニ− | Automatic load control device for hydraulic rotary motion absorbers |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS61146910A (en) | 1986-07-04 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US11105061B1 (en) | High-performance liquefaction-resistance treatment method for gravel pile of existing building foundation | |
| JPH0459405B2 (en) | ||
| JP2803409B2 (en) | Liquefaction countermeasure structure for embankment | |
| US5017046A (en) | Method of protecting a structure constructed on ground liable to be liquefied | |
| JPH08184064A (en) | Foundation structure of building | |
| JP7440864B2 (en) | Embankment reinforcement method | |
| JPH01239217A (en) | Method for protecting underground structure in sand base liable to be liquefied | |
| JPH0352256Y2 (en) | ||
| JP2816267B2 (en) | Ground fluidization prevention method | |
| JP2751652B2 (en) | Liquefaction prevention structure for lifeline structures | |
| JP2694881B2 (en) | Seismic retrofitting method for existing structures | |
| SU1673722A1 (en) | Earthquake-proof structure | |
| JP2725516B2 (en) | Liquefaction countermeasures for buried structures | |
| JPH01226921A (en) | Earthquake-proof reinforced revetment construction | |
| JPH03275813A (en) | Method for coping with liquefaction of embedded structure | |
| JP2876471B2 (en) | Lateral flow countermeasure structure | |
| JP2668922B2 (en) | Seismic structure of excavated road | |
| JPH1046619A (en) | Foundation structure of construction in sand-layer ground | |
| JP3176530B2 (en) | Liquefaction countermeasures | |
| JPH10131208A (en) | Construction method for preventing ground from lateral flow | |
| JP7469608B2 (en) | Support structure, gravity breakwater and construction method of gravity breakwater | |
| JP2807696B2 (en) | Underground structure | |
| JPS63142115A (en) | Prevention work for liquefaction of ground | |
| JPH1077625A (en) | Embedment structure of culvert | |
| JPH02132216A (en) | Base for filled ground structure |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |