JP2019199693A - Ground improvement structure and excavation method - Google Patents

Ground improvement structure and excavation method Download PDF

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JP2019199693A
JP2019199693A JP2018093007A JP2018093007A JP2019199693A JP 2019199693 A JP2019199693 A JP 2019199693A JP 2018093007 A JP2018093007 A JP 2018093007A JP 2018093007 A JP2018093007 A JP 2018093007A JP 2019199693 A JP2019199693 A JP 2019199693A
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impermeable layer
artificial impermeable
artificial
ground
thickness
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JP7075280B2 (en
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安永 正道
Masamichi Yasunaga
正道 安永
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Kajima Corp
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    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02WCLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
    • Y02W30/00Technologies for solid waste management
    • Y02W30/30Landfill technologies aiming to mitigate methane emissions

Abstract

To provide a ground improvement structure and the like which can suppress work period and cost required for an artificial impermeable layer.SOLUTION: A ground improvement structure includes: earth retaining walls 3 at both sides of an excavation position in a ground 2; and an artificial impermeable layer 4 formed by improving the ground 2 between the earth retaining walls 3 using a solidification material. An upper face of the artificial impermeable layer 4 is a horizontal surface formed in a horizontal direction. A lower face of the artificial impermeable layer 4 includes an upwardly protruding shape. A thickness of the artificial impermeable layer 4 at an intermediate portion between the earth retaining walls 3 is smaller than a thickness at a position of the earth retaining walls 3.SELECTED DRAWING: Figure 5

Description

本発明は、地盤改良構造および地盤の掘削方法に関する。   The present invention relates to a ground improvement structure and a ground excavation method.

地下構造物の構築時には地盤の掘削を行う。その際、適切な深度に不透水層が有る場合は、不透水層に達する山留壁を構築した後、切梁・腹起しを掛けながら山留壁の内側の地盤を掘削する。山留壁は外側の地盤からの土圧に抵抗するほか、地下水を遮水する遮水壁としても機能する。   The excavation of the ground is performed when the underground structure is constructed. At that time, if there is an impermeable layer at an appropriate depth, build a retaining wall that reaches the impervious layer, and then excavate the ground inside the retaining wall with hanging beams and upsets. In addition to resisting earth pressure from the outside ground, the Yamadome wall also functions as a water barrier for blocking groundwater.

一方、適切な深度に不透水層が無い場合、山留壁の内側の地盤を改良して人工の不透水層(以下、人工不透水層という)を形成することがある(例えば、特許文献1〜6)。   On the other hand, when there is no impermeable layer at an appropriate depth, an artificial impermeable layer (hereinafter referred to as an artificial impermeable layer) may be formed by improving the ground inside the mountain retaining wall (for example, Patent Document 1). ~ 6).

人工不透水層の厚さは、地下水の揚圧力によって人工不透水層に生じる曲げモーメントやせん断力に耐え得るものとする。人工不透水層は山留壁の間に設けられ、山留壁の変形を防止する地中梁としても機能する。   The thickness of the artificial impermeable layer shall be able to withstand the bending moment and shear force generated in the artificial impermeable layer due to the groundwater uplift pressure. The artificial impermeable layer is provided between the retaining walls, and also functions as an underground beam that prevents deformation of the retaining walls.

特開平11-209998号公報JP-A-11-209998 特開平11-247174号公報Japanese Patent Laid-Open No. 11-247174 特開2003-171949号公報JP 2003-171949 A 特開2001-182088号公報Japanese Patent Laid-Open No. 2001-182088 特開2004-27722号公報JP 2004-27722 A 特開2015-229822号公報JP-A-2015-229822

山留壁の離れ(スパン)が大きくなると、人工不透水層にかかる工期やコストが増加する問題がある。すなわち、人工不透水層の応力度は両側の山留壁を支点とした単純梁に一様な揚圧力が加わっているものとして求められ、山留壁のスパン(支点間距離)が大きくなると揚圧力によって生じる曲げモーメントやせん断力の最大値が大きくなる。そのため人工不透水層の厚さや強度を大きくする必要が生じ、工期やコストの面から地盤改良による人工不透水層とは別の方法を採用せざるを得ない場合もある。   When the separation (span) of the retaining wall increases, there is a problem that the construction period and cost for the artificial impermeable layer increase. In other words, the stress level of the artificial impermeable layer is calculated as a uniform beam that is applied to a simple beam with the fulcrum on both sides as the fulcrum. If the span (distance between fulcrum) of the dome wall increases, The maximum value of the bending moment and shear force generated by the pressure increases. Therefore, it becomes necessary to increase the thickness and strength of the artificial impermeable layer, and there is a case where a method different from the artificial impermeable layer by ground improvement must be adopted from the viewpoint of construction period and cost.

本発明は上記の問題に鑑みてなされたものであり、人工不透水層にかかる工期やコストを抑えることのできる地盤改良構造等を提供することを目的とする。   This invention is made | formed in view of said problem, and it aims at providing the ground improvement structure etc. which can suppress the construction period and cost concerning an artificial impermeable layer.

前述した課題を解決するための第1の発明は、地盤を固化材により改良して形成された人工不透水層を有する地盤改良構造であって、前記人工不透水層は、複数の支点において地下水の揚圧力に対して支持され、前記人工不透水層の少なくとも上面と下面のいずれかは、前記支点の間の中間部における高さと、前記支点の位置における高さの違いにより、上方または下方に凸状に形成されることを特徴とする地盤改良構造である。   A first invention for solving the above-described problem is a ground improvement structure having an artificial impermeable layer formed by improving the ground with a solidified material, wherein the artificial impermeable layer includes groundwater at a plurality of fulcrums. The at least one of the upper surface and the lower surface of the artificial impermeable layer is supported upward or downward depending on a difference in height between the fulcrum and the height at the fulcrum position. It is a ground improvement structure characterized by being formed in a convex shape.

本発明では、人工不透水層の上面や下面を上記のように凸状に形成することで、地下水の揚圧力により人工不透水層に生じるせん断力や曲げモーメントの分布に応じて、あるいは人工不透水層が地下水の揚圧力に効果的に抵抗できるように、人工不透水層の形状を最適化して改良土量等を減らし、工期やコストを抑えることができる。   In the present invention, the upper and lower surfaces of the artificial impermeable layer are formed in a convex shape as described above, depending on the distribution of shear force and bending moment generated in the artificial impermeable layer due to the groundwater uplift pressure, or artificial impermeable layer. The shape of the artificial impermeable layer can be optimized to reduce the amount of improved soil so that the permeable layer can effectively resist the groundwater pumping pressure, thereby reducing the construction period and cost.

前記人工不透水層は、前記支点の間の中間部における厚さと、前記支点の位置における厚さが異なることが望ましい。
本発明では、人工不透水層の上面または下面の凸形状によって、人工不透水層の厚さを、地下水の揚圧力により人工不透水層に生じるせん断力や曲げモーメントの分布に応じて最適化できる。
The artificial impermeable layer preferably has a thickness at an intermediate portion between the fulcrums and a thickness at the position of the fulcrum.
In the present invention, the thickness of the artificial impermeable layer can be optimized according to the distribution of shear force and bending moment generated in the artificial impermeable layer by the groundwater uplift pressure by the convex shape of the upper or lower surface of the artificial impermeable layer. .

例えば前記人工不透水層は、前記支点の間の中間部における厚さが、前記支点の位置における厚さより小さい。
地下水の揚圧力が人工不透水層に一様に加わる場合、揚圧力により人工不透水層に生じるせん断力は支点側で大きくなり、曲げモーメントは支点の間の中間部で大きくなる。せん断力の最大値に対して必要となる地盤改良厚が、曲げモーメントの最大値に対して必要となる地盤改良厚より大きい場合は、上記のように支点の間の中間部における人工不透水層の厚さを支点の位置における厚さよりも小さくすることで、上記のせん断力や曲げモーメントの分布に対し人工不透水層の厚さを最適化できる。
For example, the artificial impermeable layer has a thickness at an intermediate portion between the fulcrums smaller than a thickness at the position of the fulcrum.
When the groundwater lift pressure is uniformly applied to the artificial impermeable layer, the shear force generated in the artificial impermeable layer by the lift pressure increases on the fulcrum side, and the bending moment increases at the intermediate portion between the fulcrums. If the ground improvement thickness required for the maximum value of the shearing force is larger than the ground improvement thickness required for the maximum value of the bending moment, as described above, the artificial impermeable layer in the middle part between the fulcrums The thickness of the artificial impermeable layer can be optimized with respect to the distribution of the shearing force and the bending moment described above by making the thickness of the substrate smaller than the thickness at the position of the fulcrum.

あるいは、前記人工不透水層は、前記支点の間の中間部における厚さが、前記支点の位置における厚さより大きくてもよい。
地下水の揚圧力が小さい場合や改良土の強度が大きい場合など、人工不透水層の形状を主として地下水の揚圧力により生じる曲げモーメントによって定めることのできる場合がある。この場合は、支点の間の中間部における人工不透水層の厚さを支点の位置における厚さよりも大きくすることで、曲げモーメントの分布に対し人工不透水層の厚さを最適化できる。
Alternatively, the artificial impermeable layer may have a thickness at an intermediate portion between the fulcrums larger than a thickness at the position of the fulcrum.
There are cases where the shape of the artificial impermeable layer can be determined mainly by the bending moment generated by the groundwater lifting pressure, such as when the groundwater lifting pressure is low or the strength of the improved soil is high. In this case, by making the thickness of the artificial impermeable layer in the middle part between the fulcrums larger than the thickness at the position of the fulcrum, the thickness of the artificial impermeable layer can be optimized with respect to the bending moment distribution.

前記人工不透水層の上面および下面は、下方に凸となった形状を有し、前記支点の間の中間部における高さが前記支点の位置における高さよりも下にあることも望ましい。
このように人工不透水層を下方に凸となるアーチ状に形成することで、地下水の揚圧力に対し人工不透水層の軸圧縮力で抵抗できるようになる。これにより人工不透水層が地下水の揚圧力に効果的に抵抗でき、人工不透水層の厚さや強度を抑えることができる。
It is also desirable that the upper surface and the lower surface of the artificial impermeable layer have a shape that protrudes downward, and the height at the intermediate portion between the fulcrums is lower than the height at the position of the fulcrum.
Thus, by forming the artificial impermeable layer into an arch shape that protrudes downward, it is possible to resist the uplift pressure of the groundwater by the axial compressive force of the artificial impermeable layer. Thus, the artificial impermeable layer can effectively resist the groundwater uplift pressure, and the thickness and strength of the artificial impermeable layer can be suppressed.

前記人工不透水層の上面と下面の少なくともいずれかは、水平方向に対し傾斜した傾斜面を有し、前記傾斜面は複数の段部により段状に形成される。
本発明では人工不透水層を地盤改良によって形成することから、人工不透水層の上面や下面に傾斜を設けて凸状にする場合、その傾斜面を段状のものとできる。
At least one of the upper surface and the lower surface of the artificial impermeable layer has an inclined surface inclined with respect to the horizontal direction, and the inclined surface is formed in a step shape by a plurality of step portions.
In the present invention, since the artificial impermeable layer is formed by ground improvement, when the upper surface and the lower surface of the artificial impermeable layer are inclined to have a convex shape, the inclined surface can be stepped.

第2の発明は、地盤を固化材により改良して人工不透水層を設ける工程(a)と、前記人工不透水層の上方の地盤の掘削を行う工程(b)と、を有し、前記人工不透水層は、複数の支点において地下水の揚圧力に対して支持され、前記人工不透水層の少なくとも上面と下面のいずれかは、前記支点の間の中間部における高さと、前記支点の位置における高さの違いにより、上方または下方に凸状に形成されることを特徴とする掘削方法である。
第2の発明は、第1の発明の地盤改良構造を形成して地盤の掘削を行う掘削方法である。
2nd invention has the process (a) which improves the ground with a solidification material and provides an artificial impermeable layer, and the process (b) which excavates the ground above the artificial impermeable layer, The artificial impermeable layer is supported at a plurality of fulcrums against groundwater lifting pressure, and at least one of the upper and lower surfaces of the artificial impermeable layer has a height at an intermediate portion between the fulcrums and the position of the fulcrum. The excavation method is characterized by being formed in a convex shape upward or downward depending on the difference in height.
The second invention is an excavation method for excavating the ground by forming the ground improvement structure of the first invention.

本発明により、人工不透水層にかかる工期やコストを抑えることのできる地盤改良構造等を提供することができる。   By this invention, the ground improvement structure etc. which can hold down the construction period and cost concerning an artificial impermeable layer can be provided.

ポンプ室1を示す図。The figure which shows the pump chamber. ポンプ室1の構築方法について示す図。The figure shown about the construction method of the pump chamber. ポンプ室1の構築方法について示す図。The figure shown about the construction method of the pump chamber. 傾斜面41を示す図。The figure which shows the inclined surface 41. FIG. 地下水の揚圧力A、人工不透水層4の曲げモーメントMとせん断力S、および必要な地盤改良厚を示す図。The figure which shows the groundwater lift pressure A, the bending moment M and the shearing force S of the artificial impermeable layer 4, and required ground improvement thickness. 人工不透水層4aを示す図。The figure which shows the artificial impermeable layer 4a. 人工不透水層4bを示す図。The figure which shows the artificial impermeable layer 4b. ボックスカルバート10を示す図。The figure which shows the box culvert 10. FIG. 人工不透水層4cを示す図。The figure which shows the artificial impermeable layer 4c. 地下水の揚圧力Aと人工不透水層4cの軸圧縮力Nを示す図。The figure which shows the axial pressure N of the lifting pressure A of the groundwater and the artificial impermeable layer 4c. ポンプ室1aの構築方法について示す図。The figure shown about the construction method of the pump chamber 1a. ポンプ室1aの構築方法について示す図。The figure shown about the construction method of the pump chamber 1a. ポンプ室1aの構築方法について示す図。The figure shown about the construction method of the pump chamber 1a. 人工不透水層4’の支点を示す図。The figure which shows the fulcrum of artificial impermeable layer 4 '. 中間杭5、5’の配置が異なる例。An example in which the arrangement of the intermediate piles 5, 5 'is different. グラウンドアンカー8を用いた地盤改良構造を示す図。The figure which shows the ground improvement structure using the ground anchor. ポンプ室1bの構築方法について示す図。The figure shown about the construction method of the pump chamber 1b. ポンプ室1bの構築方法について示す図。The figure shown about the construction method of the pump chamber 1b. ポンプ室1bの構築方法について示す図。The figure shown about the construction method of the pump chamber 1b.

以下、図面に基づいて本発明の好適な実施形態について詳細に説明する。   Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the drawings.

[第1の実施形態]
(1.ポンプ室1)
図1は、本発明の実施形態に係る地盤改良構造を利用して構築されるポンプ室1を示す図である。
[First Embodiment]
(1. Pump room 1)
FIG. 1 is a diagram showing a pump chamber 1 constructed using a ground improvement structure according to an embodiment of the present invention.

ポンプ室1は、火力発電所、原子力発電所などで海水を冷却水として使用するために用いられる。海水は、取水口、取水路を通ってポンプ室1に導かれ、循環水ポンプによって発電所のタービン室に供給される。   The pump chamber 1 is used for using seawater as cooling water in a thermal power plant, a nuclear power plant, or the like. Seawater is guided to the pump chamber 1 through the intake port and intake channel, and is supplied to the turbine chamber of the power plant by the circulating water pump.

ポンプ室1は地盤2に構築される地下構造物であり、コンクリートによって形成された底版11と側壁12からなる函状の躯体を有する。側壁12の間の中間部にはコンクリートによる分流壁13が設けられる。   The pump chamber 1 is an underground structure constructed on the ground 2, and has a box-shaped casing made up of a bottom plate 11 and side walls 12 made of concrete. A diversion wall 13 made of concrete is provided in an intermediate portion between the side walls 12.

なお図1の符号4は人工不透水層であるが、これについては後述する。   In addition, although the code | symbol 4 of FIG. 1 is an artificial impermeable layer, this is mentioned later.

(2.ポンプ室1の構築方法)
図2、3はポンプ室1の構築方法について示す図である。本実施形態ではポンプ室1の構築に先立って地盤改良構造を形成し、その後地盤2の掘削が行われるが、以下ではその掘削方法についても説明する。
(2. Construction method of pump chamber 1)
2 and 3 are diagrams showing a construction method of the pump chamber 1. In this embodiment, the ground improvement structure is formed prior to the construction of the pump chamber 1 and then the ground 2 is excavated. The excavation method will be described below.

すなわち、本実施形態では、ポンプ室1を構築する際、まず図2(a)に示すように山留壁3を地盤2に施工する。   That is, in this embodiment, when constructing the pump chamber 1, first, the mountain retaining wall 3 is constructed on the ground 2 as shown in FIG.

山留壁3は地盤2の掘削箇所(ポンプ室1の構築箇所)の両側に設けられる。山留壁3は外側の地盤2からの土圧に抵抗するとともに、地下水の遮水を行う遮水壁としても機能する。山留壁3は特に限定されず、鋼矢板壁、鋼管矢板壁、芯材入りのソイルモルタル壁などを用いることができる。   The mountain retaining wall 3 is provided on both sides of the excavation site of the ground 2 (the construction site of the pump chamber 1). The mountain retaining wall 3 resists earth pressure from the outer ground 2 and also functions as a water shielding wall that shields groundwater. The mountain retaining wall 3 is not particularly limited, and a steel sheet pile wall, a steel pipe sheet pile wall, a soil mortar wall containing a core material, and the like can be used.

山留壁3を施工した後、図2(b)に示すように山留壁3の間で地盤2の改良を行い、人工不透水層4を形成する。これにより、人工不透水層4を含む地盤改良構造が形成される。本実施形態では人工不透水層4が山留壁3の底部に当たる深さで形成され、人工不透水層4の下端と山留壁3の下端がほぼ同じ深さにある。   After constructing the mountain retaining wall 3, the ground 2 is improved between the mountain retaining walls 3 as shown in FIG. 2 (b) to form the artificial impermeable layer 4. Thereby, the ground improvement structure including the artificial impermeable layer 4 is formed. In the present embodiment, the artificial impermeable layer 4 is formed at a depth that hits the bottom of the mountain retaining wall 3, and the lower end of the artificial impermeable layer 4 and the lower end of the mountain retaining wall 3 are substantially at the same depth.

人工不透水層4と山留壁3の間には付着力が生じ、この付着力は地下水の揚圧力に対する抵抗力を人工不透水層4に与える。すなわち、人工不透水層4は、山留壁3の位置を支点として地下水の揚圧力に対し支持される。   Adhesive force is generated between the artificial impermeable layer 4 and the mountain retaining wall 3, and this adhesive force gives the artificial impermeable layer 4 resistance to the groundwater uplift pressure. That is, the artificial impermeable layer 4 is supported against the groundwater uplift pressure with the position of the mountain retaining wall 3 as a fulcrum.

人工不透水層4の上面は水平方向に形成される水平面であるが、人工不透水層4の下面は、山留壁3の間の中間部における高さと山留壁3の位置における高さの違いによって上方に凸となっている。そのため、人工不透水層4の厚さ(地盤改良厚)は山留壁3の間の中間部と山留壁3の位置とで異なり、中間部での厚さが山留壁3の位置における厚さよりも小さくなっている。   Although the upper surface of the artificial impermeable layer 4 is a horizontal plane formed in the horizontal direction, the lower surface of the artificial impermeable layer 4 has a height at an intermediate portion between the mountain retaining walls 3 and a height at the position of the mountain retaining wall 3. It is convex upward due to the difference. Therefore, the thickness of the artificial impermeable layer 4 (ground improvement thickness) is different between the intermediate portion between the mountain retaining walls 3 and the position of the mountain retaining wall 3, and the thickness at the intermediate portion is at the position of the mountain retaining wall 3. It is smaller than the thickness.

人工不透水層4の下面では、山留壁3側の両端部に傾斜面41が、山留壁3の間の中間部に水平面42が設けられる。傾斜面41は、山留壁3の間の中間部側に行くにつれ高くなるよう直線状に傾斜する。水平面42は傾斜面41の上端同士を接続する。   On the lower surface of the artificial impermeable layer 4, inclined surfaces 41 are provided at both ends on the mountain retaining wall 3 side, and a horizontal surface 42 is provided at an intermediate portion between the mountain retaining walls 3. The inclined surface 41 is linearly inclined so as to become higher as it goes to the intermediate portion side between the mountain retaining walls 3. The horizontal surface 42 connects the upper ends of the inclined surfaces 41.

人工不透水層4の形成方法(地盤2の改良方法)は特に限定されず、例えば既知の噴射混合攪拌工法、機械混合攪拌工法、薬液注入工法などを用い、セメントミルクなどの固化材で地盤2を固化して改良することにより人工不透水層4を形成できる。これらの工法では施工深度を段階的に変更しながら地盤改良を行うことから、人工不透水層4の傾斜面41は、実際には図4に示すように複数の段部411から構成される。   The formation method of the artificial water-impermeable layer 4 (the improvement method of the ground 2) is not particularly limited. For example, the ground 2 can be made of a solidified material such as cement milk using a known jet mixing stirring method, mechanical mixing stirring method, chemical injection method, or the like. The artificial impermeable layer 4 can be formed by solidifying and improving. In these methods, since the ground is improved while changing the construction depth in stages, the inclined surface 41 of the artificial impermeable layer 4 is actually composed of a plurality of step portions 411 as shown in FIG.

こうして人工不透水層4を形成した後、図3(a)に示すように山留壁3の間にある人工不透水層4の上方の地盤2を床付け位置まで掘削する。地盤2の掘削時には必要に応じて切梁(不図示)を山留壁3の間に架け渡す。   After the artificial impermeable layer 4 is formed in this way, the ground 2 above the artificial impermeable layer 4 between the mountain retaining walls 3 is excavated to the flooring position as shown in FIG. When excavating the ground 2, a cut beam (not shown) is bridged between the retaining walls 3 as necessary.

その後、図3(b)に示すようにポンプ室1の構築を行う。本実施形態では切梁や山留壁3をポンプ室1の構築時に撤去するが、山留壁3は残置する場合もある。また本実施形態では掘削時の床付け位置(ポンプ室1の底版11の下面位置に対応する)を人工不透水層4の上面としているが、それより高い位置でもよい。その場合はポンプ室1の底版11と人工不透水層4の間に地盤2が介在する。なお、ポンプ室1の外面の位置は山留壁3の内面の位置に対応しているが、ポンプ室1の外面の位置はそれより内側でも良い。   Thereafter, the pump chamber 1 is constructed as shown in FIG. In the present embodiment, the beam and the mountain retaining wall 3 are removed when the pump chamber 1 is constructed, but the mountain retaining wall 3 may be left behind. In the present embodiment, the flooring position during excavation (corresponding to the lower surface position of the bottom plate 11 of the pump chamber 1) is the upper surface of the artificial impermeable layer 4, but a higher position may be used. In that case, the ground 2 is interposed between the bottom plate 11 of the pump chamber 1 and the artificial impermeable layer 4. Although the position of the outer surface of the pump chamber 1 corresponds to the position of the inner surface of the mountain retaining wall 3, the position of the outer surface of the pump chamber 1 may be inside.

前記した人工不透水層4の形状は、地下水の揚圧力により人工不透水層4に生じる曲げモーメントやせん断力の分布に応じて人工不透水層4の厚さを最適化するように定められたものであり、これにより人工不透水層4の改良土量等を減らして工期やコストを抑えることができる。   The shape of the artificial impermeable layer 4 described above was determined so as to optimize the thickness of the artificial impermeable layer 4 according to the bending moment and shear force distribution generated in the artificial impermeable layer 4 due to the groundwater uplift pressure. Thus, the amount of improved soil of the artificial impermeable layer 4 can be reduced, and the construction period and cost can be suppressed.

すなわち、図5(a)のように地下水の揚圧力Aが人工不透水層4に一様に加わる場合、人工不透水層4を山留壁3の位置を支点(図中▽参照)として支持される単純梁としたときに、人工不透水層4に生じる曲げモーメントM(t・m/m)とせん断力S(t/m)の概略を示したものが図5(b)である。なおせん断力Sについては絶対値を示している。   That is, when the groundwater lifting pressure A is uniformly applied to the artificial impermeable layer 4 as shown in FIG. 5A, the artificial impermeable layer 4 is supported with the position of the mountain retaining wall 3 as a fulcrum (see ▽ in the figure). FIG. 5B shows an outline of the bending moment M (t · m / m) and the shearing force S (t / m) generated in the artificial impermeable layer 4 when a simple beam is used. The shear force S is an absolute value.

図5(c)は、曲げモーメントMに対し必要となる地盤改良厚h1(m)とせん断力Sに対し必要となる地盤改良厚h2(m)を示したものであり、h1、h2はそれぞれ以下の式(1)、(2)で算出することができる。式(1)、(2)において、b(m)は改良土の奥行き方向(図5(a)等の紙面法線方向に対応する)の単位長さであり、例えばb=1とする。また、σ(tf/m2)、τ(tf/m2) はそれぞれ改良土の圧縮許容応力度とせん断許容応力度である。
h1=(6・M/(σ・b))0.5…(1)
h2=S/(τ・b)…(2)
Fig. 5 (c) shows the ground improvement thickness h1 (m) required for the bending moment M and the ground improvement thickness h2 (m) required for the shear force S. It can be calculated by the following formulas (1) and (2). In equations (1) and (2), b (m) is the unit length in the depth direction of the improved soil (corresponding to the normal direction of the paper surface in FIG. 5A), for example, b = 1. Also, σ (tf / m 2 ) and τ (tf / m 2 ) are the allowable compressive stress level and the allowable shear stress level of the improved soil, respectively.
h1 = (6 · M / (σ · b)) 0.5 (1)
h2 = S / (τ · b) (2)

図5(b)、(c)に示すように、人工不透水層4に一様な揚圧力Aが加わる場合、人工不透水層4に生じるせん断力Sは山留壁3の位置で大きくなり、曲げモーメントMは山留壁3の間の中間部で大きくなる。またこの例では、せん断力Sの最大値に対して必要となる地盤改良厚h2が、曲げモーメントの最大値に対して必要となる地盤改良厚h1より大きい。   As shown in FIGS. 5 (b) and 5 (c), when a uniform lifting pressure A is applied to the artificial impermeable layer 4, the shear force S generated in the artificial impermeable layer 4 increases at the position of the mountain retaining wall 3. The bending moment M increases at an intermediate portion between the mountain retaining walls 3. In this example, the ground improvement thickness h2 required for the maximum value of the shear force S is larger than the ground improvement thickness h1 required for the maximum value of the bending moment.

本実施形態の人工不透水層4の下面の形状は、図5(c)の実線Bに示すように、曲げモーメントMに対し必要となる地盤改良厚h1とせん断力Sに対し必要となる地盤改良厚h2のいずれも満たし、且つ改良土量をできるだけ少なくするように考慮した結果、前記のように山留壁3の位置で人工不透水層4が厚く形成され、山留壁3の間の中間部で人工不透水層4がそれよりも薄く形成されるように、上方に凸状としたものである。   The shape of the lower surface of the artificial impermeable layer 4 of the present embodiment is the ground required for the ground improvement thickness h1 and the shear force S required for the bending moment M, as shown by the solid line B in FIG. As a result of satisfying all of the improved thickness h2 and reducing the amount of improved soil as much as possible, the artificial impermeable layer 4 is formed thick at the position of the mountain retaining wall 3 as described above, and the space between the mountain retaining walls 3 is increased. The artificial impermeable layer 4 is convex upward so that it is formed thinner in the middle part.

これにより、図5(c)の鎖線Cに示すように必要な地盤改良厚の最大値に合わせて地盤改良厚を一定にする(人工不透水層4の下面を水平とする)場合に比べ、改良土量を30%程度低減できる。   Thereby, as shown in the chain line C of FIG. 5C, the ground improvement thickness is made constant according to the maximum value of the required ground improvement thickness (the lower surface of the artificial impermeable layer 4 is horizontal), Improved soil volume can be reduced by about 30%.

なお、本実施形態の人工不透水層4に代えて、当該人工不透水層4を上下反転させた形状の人工不透水層を用いることも可能であり、これは後述する図6、7の例でも同様である。例えば本実施形態では、人工不透水層4を上下反転して下面を水平面、上面を下に凸状とすることでも実線Bに示す地盤改良厚を実現できる。   In addition, it can replace with the artificial impermeable layer 4 of this embodiment, and can also use the artificial impermeable layer of the shape which reversed the said artificial impermeable layer 4 up and down, and this is the example of FIG. 6, 7 mentioned later. But the same is true. For example, in the present embodiment, the ground improvement thickness shown by the solid line B can also be realized by turning the artificial impermeable layer 4 upside down so that the lower surface is a horizontal surface and the upper surface is convex downward.

以上説明したように、本実施形態によれば、人工不透水層4の凸形状によって、地下水の揚圧力Aにより人工不透水層4に生じるせん断力Sや曲げモーメントMの分布に応じて人工不透水層4の厚さを最適化し、改良土量等を減らして工期やコストを抑えることができる。   As described above, according to the present embodiment, the artificial impermeable layer 4 has a convex shape, and the artificial impermeable layer 4 has an artificially impermeable layer according to the distribution of the shearing force S and the bending moment M generated in the artificial impermeable layer 4 by the groundwater lift pressure A. The thickness of the water permeable layer 4 can be optimized, the amount of improved soil can be reduced, and the construction period and cost can be suppressed.

すなわち、地下水の揚圧力Aが人工不透水層4に一様に加わる場合、揚圧力Aにより人工不透水層4に生じるせん断力Sは山留壁3の位置で大きくなり、曲げモーメントMは山留壁3の間の中間部で大きくなる。せん断力Sの最大値に対して必要となる地盤改良厚h2が、曲げモーメントMの最大値に対して必要となる地盤改良厚h1より大きい場合は、山留壁3の間の中間部における人工不透水層4の厚さを山留壁3の位置における厚さよりも小さくすることで、上記のせん断力Sや曲げモーメントMの分布に対し人工不透水層4の厚さを最適化できる。   That is, when the groundwater lifting pressure A is uniformly applied to the artificial impermeable layer 4, the shear force S generated in the artificial impermeable layer 4 by the lifting pressure A increases at the position of the mountain retaining wall 3, and the bending moment M is the mountain. It becomes large at the intermediate part between the retaining walls 3. When the ground improvement thickness h2 required for the maximum value of the shearing force S is larger than the ground improvement thickness h1 required for the maximum value of the bending moment M, an artificial part in the intermediate portion between the retaining walls 3 is used. By making the thickness of the impermeable layer 4 smaller than the thickness at the position of the mountain retaining wall 3, the thickness of the artificial impermeable layer 4 can be optimized with respect to the distribution of the shearing force S and the bending moment M described above.

また本実施形態ではせん断力Sに耐えるべく人工不透水層4の山留壁3側の端部を厚くしているので、山留壁3と一体に挙動し実質的な支点として機能する人工不透水層4の範囲が内側に拡がり、実質的な支点間距離が小さくなって人工不透水層4に生じる曲げモーメントMの最大値が小さくなる効果も期待できる。そのため、山留壁3の間の中間部での人工不透水層4の厚さをより小さくすることも可能である。   In this embodiment, since the end of the artificial impermeable layer 4 on the side of the retaining wall 3 is thickened to withstand the shearing force S, the artificial impermeable layer 4 behaves integrally with the retaining wall 3 and functions as a substantial fulcrum. The range of the water permeable layer 4 expands inward, and the effect of reducing the maximum value of the bending moment M generated in the artificial water-impermeable layer 4 by reducing the substantial distance between fulcrums can be expected. Therefore, it is also possible to make the thickness of the artificial impermeable layer 4 in the intermediate part between the mountain retaining walls 3 smaller.

また本実施形態では、人工不透水層4を地盤改良によって形成することから、傾斜面41は複数の段部411により構成される段状のものとできる。   Moreover, in this embodiment, since the artificial impermeable layer 4 is formed by ground improvement, the inclined surface 41 can be made into the step shape comprised by the several step part 411. FIG.

しかしながら、本発明はこれに限らない。例えば人工不透水層4の形状は、曲げモーメントMに対し必要となる地盤改良厚h1とせん断力Sに対し必要となる地盤改良厚h2のいずれも満たし、且つ改良土量をできるだけ少なくするように定めればよく、前記の実施形態で示したものに限らない。   However, the present invention is not limited to this. For example, the shape of the artificial water-impermeable layer 4 satisfies both the ground improvement thickness h1 required for the bending moment M and the ground improvement thickness h2 required for the shear force S, and the amount of improved soil is minimized. What is necessary is just to define and it is not restricted to what was shown by the said embodiment.

例えば図5(c)の破線B’に示すように地盤改良厚を設定することで、図6に示すように人工不透水層4aの下面を上方に凸となる略円弧状の曲面とすることも可能である。この場合も人工不透水層4aの下面に傾斜面43を有することとなるが、この傾斜面43も図4の例と同様複数の段部により段状に構成される。   For example, by setting the ground improvement thickness as shown by the broken line B ′ in FIG. 5 (c), the lower surface of the artificial impermeable layer 4a is formed into a substantially arc-shaped curved surface that protrudes upward as shown in FIG. Is also possible. Also in this case, the inclined surface 43 is provided on the lower surface of the artificial impermeable layer 4a, and the inclined surface 43 is also formed in a step shape by a plurality of step portions as in the example of FIG.

また、地下水の揚圧力Aが小さい場合や改良土の強度が大きい場合など、人工不透水層の形状を主として曲げモーメントMによって定めることのできる場合がある。曲げモーメントMのみを考慮する場合では、図7に示すように、人工不透水層4bの下面を下方に凸となる略円弧状の曲面にし、山留壁3の間の中間部での人工不透水層4bの厚さを、山留壁3の位置における厚さより大きくしてもよい。人工不透水層4bの下面の傾斜面44は図4の例と同様複数の段部により段状に構成される。   Further, there are cases where the shape of the artificial impermeable layer can be determined mainly by the bending moment M, such as when the groundwater lifting pressure A is low or the strength of the improved soil is high. In the case of considering only the bending moment M, as shown in FIG. 7, the lower surface of the artificial impermeable layer 4b is formed into a substantially arcuate curved surface that protrudes downward, and the artificial imperfection at the intermediate portion between the mountain retaining walls 3 is formed. The thickness of the water permeable layer 4 b may be larger than the thickness at the position of the mountain retaining wall 3. The inclined surface 44 on the lower surface of the artificial water-impermeable layer 4b is formed in a step shape by a plurality of step portions as in the example of FIG.

また、本実施形態はポンプ室1の例を挙げて説明したが、これに限ることはなく、ポンプ室1の上流側に設けられる取水ピット、またタービン室から放出された海水を放水路に放水する放水ピットなどにも適用できる。また分流壁13は省略される場合もある。   Moreover, although this embodiment demonstrated and demonstrated the example of the pump chamber 1, it does not restrict to this, The water intake pit provided in the upstream of the pump chamber 1, and the seawater discharge | released from the turbine chamber are discharged into a discharge channel It can also be applied to water discharge pits. Further, the flow dividing wall 13 may be omitted.

さらに、本実施形態はその他の地下構造物の構築時にも適用可能であり、例えば図8のような道路トンネルなどのボックスカルバート10の構築時にも適用できる。図8のボックスカルバート10は底版110、側壁120、中壁(あるいは柱)130、頂版140を有する。図8は2連形式のボックスカルバート10の例であるが、4連形式のボックスカルバートや中壁130の無い1連形式のボックスカルバートなどにも同様に適用できる。ボックスカルバート10の構築方法は前記と略同様である。ただし、頂版140を構築した後、その上部は埋戻土で埋め戻される。   Furthermore, the present embodiment can be applied to the construction of other underground structures, and can be applied to the construction of a box culvert 10 such as a road tunnel as shown in FIG. The box culvert 10 in FIG. 8 has a bottom plate 110, a side wall 120, a middle wall (or column) 130, and a top plate 140. FIG. 8 shows an example of the double box culvert 10, but the present invention can be similarly applied to a quadruple box culvert or a single box culvert without the inner wall 130. The construction method of the box culvert 10 is substantially the same as described above. However, after the top plate 140 is constructed, the upper part thereof is backfilled with backfill.

また、本実施形態では山留壁3が奥行き方向(図2(a)等の紙面法線方向に対応する)に延長し、人工不透水層4、4a、4bの断面形状も奥行き方向で一定であるが、例えば山留壁3が円筒状に形成される場合もあり、この場合は平面のそれぞれの方向の断面が前記した人工不透水層4、4a、4bの断面形状となればよい。例えば図7の人工不透水層4bの場合、山留壁3が円筒状であれば、平面のそれぞれの方向の断面が図7のような形状となるように、その下面をレンズ状とする。   In this embodiment, the mountain retaining wall 3 extends in the depth direction (corresponding to the normal direction of the paper surface in FIG. 2A), and the cross-sectional shapes of the artificial impermeable layers 4, 4a, 4b are also constant in the depth direction. However, for example, the mountain retaining wall 3 may be formed in a cylindrical shape. In this case, the cross section in each direction of the plane may be the cross sectional shape of the artificial impermeable layers 4, 4 a, 4 b described above. For example, in the case of the artificial impermeable layer 4b shown in FIG. 7, if the mountain retaining wall 3 is cylindrical, the lower surface thereof is formed in a lens shape so that the cross-section in each direction of the plane has a shape as shown in FIG.

以下、本発明の別の例を第2、3の実施形態として説明する。第2、3の実施形態は第1の実施形態と異なる構成について主に説明し、同様の構成については図等で同じ符号を付すなどして説明を省略する。   Hereinafter, another example of the present invention will be described as second and third embodiments. The second and third embodiments will mainly describe different configurations from the first embodiment, and the same configurations will be denoted by the same reference numerals in the drawings and the like, and description thereof will be omitted.

[第2の実施形態]
第2の実施形態では、図9に示すように人工不透水層4cの上面および下面が下方に凸となる略円弧状の曲面であり、人工不透水層4cの上面および下面の山留壁3の間の中間部における高さが、山留壁3の位置における高さよりも下にある。人工不透水層4cの上面および下面の傾斜面45、46は図4の例と同様複数の段部により段状に構成される。なお図9は山留壁3の間の地盤2を床付け位置まで掘削した状態であり、本実施形態では人工不透水層4cと床付け位置の間に地盤2が介在する。
[Second Embodiment]
In the second embodiment, as shown in FIG. 9, the upper and lower surfaces of the artificial impermeable layer 4c are substantially arc-shaped curved surfaces that protrude downward, and the mountain retaining walls 3 on the upper and lower surfaces of the artificial impermeable layer 4c. The height at the intermediate portion between the two is lower than the height at the position of the mountain retaining wall 3. The upper and lower inclined surfaces 45 and 46 of the artificial impermeable layer 4c are formed in a step shape by a plurality of step portions as in the example of FIG. FIG. 9 shows a state where the ground 2 between the mountain retaining walls 3 is excavated to the flooring position. In this embodiment, the ground 2 is interposed between the artificial impermeable layer 4c and the flooring position.

本実施形態では、これにより人工不透水層4cを下方に凸となる略円弧のアーチ状に形成し、地下水の揚圧力に効果的に抵抗できるように人工不透水層4cの形状を最適化する。   In the present embodiment, the artificial impermeable layer 4c is thereby formed into a substantially arcuate arch that protrudes downward, and the shape of the artificial impermeable layer 4c is optimized so as to effectively resist the groundwater uplift pressure. .

すなわち、本実施形態では図10(a)に示すようにアーチ状の人工不透水層4cが地下水の揚圧力Aに対し軸圧縮力Nによって抵抗し、その力を山留壁3に伝達する。これにより、人工不透水層4cに高い耐力を与えて人工不透水層4cの厚さや強度を抑えることができる。   That is, in this embodiment, as shown in FIG. 10A, the arch-shaped artificial impermeable layer 4 c resists the groundwater lift pressure A by the axial compression force N and transmits the force to the mountain retaining wall 3. Thereby, high proof stress can be given to the artificial impermeable layer 4c, and the thickness and intensity | strength of the artificial impermeable layer 4c can be suppressed.

この場合、人工不透水層4cに必要な地盤改良厚t(m)は、下記の式(3)で表すことができる。式(3)において、σ(tf/m2)は改良土の圧縮許容応力度である。またN(t/m)は軸圧縮力である。
t=N/σ…(3)
In this case, the ground improvement thickness t (m) required for the artificial impermeable layer 4c can be expressed by the following equation (3). In Equation (3), σ (tf / m 2 ) is the degree of compressive allowable stress of the improved soil. N (t / m) is the axial compression force.
t = N / σ (3)

ここで、軸圧縮力Nは下記の式(4)で表すことができる。
N=w・R…(4)
Here, the axial compression force N can be expressed by the following equation (4).
N = w · R (4)

式(4)のw(t/m2)は地下水の揚圧力Aの値である。またR(m)はアーチ半径であり、人工不透水層4cのスパンL(m)とライズh(m)を用いて下記の式(5)で表すことができる(図10(b)参照)。
R=L/(8・h)+h/2…(5)
In formula (4), w (t / m 2 ) is the value of the groundwater lift pressure A. R (m) is the arch radius and can be expressed by the following equation (5) using the span L (m) and the rise h (m) of the artificial impermeable layer 4c (see FIG. 10B). .
R = L 2 / (8 · h) + h / 2 (5)

このように、本実施形態では、アーチ状の人工不透水層4cが地下水の揚圧力Aに対しその軸圧縮力Nによって抵抗し、これにより人工不透水層4cに高い耐力を与えて人工不透水層4cの厚さや強度を抑えることができる。人工不透水層4cの厚さは、軸圧縮力Nに耐え、これを山留壁3に伝達できるように定められるが、本実施形態では人工不透水層4cの全体を薄くできることから第1の実施形態に比べても改良土量を少なくできる。また本実施形態でも人工不透水層4cの下端と山留壁3の下端がほぼ同じ深さにあるが、人工不透水層4cを薄くする結果、山留壁3の根入れ深さも小さくなり工期やコストを低減できる。   Thus, in this embodiment, the arch-shaped artificial impermeable layer 4c resists the groundwater lift pressure A by its axial compressive force N, thereby providing the artificial impermeable layer 4c with high proof stress and artificial impermeable water. The thickness and strength of the layer 4c can be suppressed. The thickness of the artificial impermeable layer 4c is determined so that it can withstand the axial compressive force N and can be transmitted to the mountain retaining wall 3. However, in the present embodiment, the entire thickness of the artificial impermeable layer 4c can be reduced. Compared to the embodiment, the amount of improved soil can be reduced. Also in this embodiment, the lower end of the artificial impermeable layer 4c and the lower end of the mountain retaining wall 3 are at substantially the same depth. However, as a result of making the artificial impermeable layer 4c thinner, the root depth of the mountain retaining wall 3 becomes smaller and the construction period And cost can be reduced.

なお、上記の地盤改良厚tを満たしたうえで、第1の実施形態と同様、山留壁3の位置における人工不透水層4cの厚さを山留壁3の間の中間部より大きくすることも可能である。また前記した図7の例においても、地下水の揚圧力が大きくなり上面にクラックが発生するようなケースでは、本実施形態と同様、軸圧縮力によって揚圧力に抵抗するアーチ状の抵抗機構が生じると考えられる。   In addition, after satisfy | filling said ground improvement thickness t, the thickness of the artificial impermeable layer 4c in the position of the mountain retaining wall 3 is made larger than the intermediate part between the mountain retaining walls 3 similarly to 1st Embodiment. It is also possible. Also in the case of FIG. 7 described above, in the case where the groundwater lift pressure increases and cracks occur on the upper surface, an arch-like resistance mechanism that resists the lift pressure is generated by the axial compression force as in this embodiment. it is conceivable that.

[第3の実施形態]
第3の実施形態は、切梁の支持用の中間杭を利用して人工不透水層に生じる曲げモーメントやせん断力を小さくし、人工不透水層にかかる工期やコストを低減する例である。
[Third Embodiment]
The third embodiment is an example in which the bending moment and shear force generated in the artificial impermeable layer are reduced by using the intermediate pile for supporting the cut beam to reduce the construction period and cost for the artificial impermeable layer.

すなわち、本実施形態では、ポンプ室を構築する際、まず図11(a)に示すように山留壁3と中間杭5を地盤2に施工する。   That is, in this embodiment, when constructing the pump chamber, first, the mountain retaining wall 3 and the intermediate pile 5 are constructed on the ground 2 as shown in FIG.

中間杭5(中間柱ともいう)は山留壁3の間に打設する鋼製の鉛直材であり、切梁の支持を行うためのものである。本実施形態では中間杭5が山留壁3のスパン中央部で設けられる。中間杭5としては例えばH形鋼を用い、その下端をコンクリート等による固定部6で固定する。   The intermediate pile 5 (also referred to as an intermediate column) is a steel vertical material placed between the mountain retaining walls 3 and is used to support the cut beam. In this embodiment, the intermediate pile 5 is provided at the center of the span of the mountain retaining wall 3. As the intermediate pile 5, for example, H-shaped steel is used, and its lower end is fixed by a fixing portion 6 made of concrete or the like.

こうして山留壁3と中間杭5を施工した後、図11(b)に示すように山留壁3の間で地盤2の改良を行い、人工不透水層4’を形成する。これにより、人工不透水層4’を含む地盤改良構造が形成される。   After the mountain retaining wall 3 and the intermediate pile 5 are thus constructed, the ground 2 is improved between the mountain retaining walls 3 as shown in FIG. 11 (b) to form an artificial impermeable layer 4 '. Thereby, the ground improvement structure including the artificial impermeable layer 4 'is formed.

人工不透水層4’は山留壁3の底部に当たる深さで形成され、前記と同様、人工不透水層4’の下端と山留壁3の下端の位置はほぼ一致する。また中間杭5の下部は人工不透水層4’に埋設される。特に本実施形態では、中間杭5の下部が人工不透水層4’を貫通してその下端が人工不透水層4’より深い位置にある。   The artificial impermeable layer 4 ′ is formed to a depth corresponding to the bottom of the mountain retaining wall 3, and the lower end of the artificial impermeable layer 4 ′ and the lower end of the mountain retaining wall 3 substantially coincide with each other as described above. The lower part of the intermediate pile 5 is buried in the artificial impermeable layer 4 '. In particular, in the present embodiment, the lower portion of the intermediate pile 5 penetrates the artificial impermeable layer 4 ′ and the lower end thereof is at a deeper position than the artificial impermeable layer 4 ′.

人工不透水層4’を形成した後、図12(a)、(b)に示すように、山留壁3の間の地盤2の掘削と切梁7の設置を繰り返す。切梁7の一端は腹起し70を介して山留壁3に接続し、他端は中間杭5に取り付ける。これにより山留壁3と中間杭5の間で切梁7を支持させる。   After the artificial impermeable layer 4 ′ is formed, the excavation of the ground 2 between the mountain retaining walls 3 and the installation of the beam 7 are repeated as shown in FIGS. 12 (a) and 12 (b). One end of the cut beam 7 is erected and connected to the mountain retaining wall 3 through 70 and the other end is attached to the intermediate pile 5. Thereby, the cut beam 7 is supported between the mountain retaining wall 3 and the intermediate pile 5.

こうして山留壁3の間の地盤2を図13(a)に示すように床付け位置まで掘削した後、図13(b)に示すようにポンプ室1aの構築を行う。ポンプ室1aの構築時、中間杭5と切梁7は適当な時点で撤去する。例えば切梁7はポンプ室1aの底版11と側壁12を下から順に構築するのに応じて下段から順に撤去し、側壁12を頂部まで構築した後中間杭5を底版11上で切断して撤去し、その後分流壁13を構築する。   After excavating the ground 2 between the mountain retaining walls 3 to the flooring position as shown in FIG. 13 (a), the pump chamber 1a is constructed as shown in FIG. 13 (b). During the construction of the pump chamber 1a, the intermediate pile 5 and the beam 7 are removed at an appropriate time. For example, the beam 7 is removed in order from the bottom as the bottom plate 11 and the side wall 12 of the pump chamber 1a are constructed from the bottom, and after the side wall 12 is constructed to the top, the intermediate pile 5 is cut on the bottom plate 11 and removed. Then, the flow dividing wall 13 is constructed.

本実施形態では中間杭5の下端が人工不透水層4’より深い位置にあり、中間杭5の人工不透水層4’以深の部分によって人工不透水層4’をその下方の地盤2にアンカーし、地下水の揚圧力に対する抵抗力を中間杭5の位置で人工不透水層4’に与えて人工不透水層4’の浮き上がりを防止する。   In the present embodiment, the lower end of the intermediate pile 5 is deeper than the artificial impermeable layer 4 ′, and the artificial impermeable layer 4 ′ is anchored to the lower ground 2 by a portion deeper than the artificial impermeable layer 4 ′ of the intermediate pile 5. Then, resistance against the groundwater lifting pressure is applied to the artificial impermeable layer 4 ′ at the position of the intermediate pile 5 to prevent the artificial impermeable layer 4 ′ from being lifted.

これにより、図14に示すように、地下水の揚圧力Aに対し人工不透水層4’を支持する支点(図中▽で示す)を、山留壁3の位置に加えて中間杭5の位置で新たに形成することができる。   Accordingly, as shown in FIG. 14, a fulcrum (indicated by ▽ in the figure) for supporting the artificial impermeable layer 4 ′ with respect to the groundwater lifting pressure A is added to the position of the mountain retaining wall 3 and the position of the intermediate pile 5. Can be newly formed.

従来の構造では人工不透水層4’の支点が山留壁3の位置のみであり、支点間距離が山留壁3の離れ(スパン)となっていたのが、中間杭5の位置に揚圧力Aに抵抗する支点が新たに追加されることにより支点間距離が従来の1/2となる。そのため、揚圧力Aによって人工不透水層4’に生じる曲げモーメントとせん断力の最大値はそれぞれ従来の1/4、1/2となる。   In the conventional structure, the fulcrum of the artificial impermeable layer 4 ′ is only the position of the retaining wall 3, and the distance between the fulcrum is the separation (span) of the retaining wall 3. By newly adding a fulcrum that resists pressure A, the distance between the fulcrums becomes 1/2 of the conventional distance. Therefore, the maximum values of the bending moment and the shearing force generated in the artificial impermeable layer 4 ′ by the lifting pressure A are 1/4 and 1/2, respectively, of the prior art.

これにより、人工不透水層4’を薄くしたり強度を抑えたりすることができ、人工不透水層4’にかかる工期やコストを抑えることができる。なお、人工不透水層4’の形状は、上記のように中間杭5の位置が新たな支点となることから、図2(b)等で説明した人工不透水層4と同様の形状が各山留壁3と中間杭5の間で計2つ形成されたものとなる。   Thereby, the artificial impermeable layer 4 ′ can be thinned and the strength can be suppressed, and the construction period and cost for the artificial impermeable layer 4 ′ can be suppressed. In addition, since the position of the intermediate pile 5 becomes a new fulcrum as described above, the shape of the artificial impermeable layer 4 ′ has the same shape as the artificial impermeable layer 4 described with reference to FIG. A total of two are formed between the mountain retaining wall 3 and the intermediate pile 5.

このように、本実施形態によれば、切梁7の支持用の中間杭5を利用して、山留壁3の間で人工不透水層4’に地下水の揚圧力Aに対する抵抗力を与え、揚圧力Aに対し人工不透水層4’を支持する支点を新たに形成することができる。これにより人工不透水層4’の支点間距離が小さくなり、地下水の揚圧力Aにより人工不透水層4’に生じる曲げモーメントやせん断力を小さくすることができる。そのため、人工不透水層4’を薄くしたり強度を抑えたりすることができ、人工不透水層4’にかかる工期やコストをさらに抑えることができる。   Thus, according to this embodiment, resistance against the groundwater uplift pressure A is given to the artificial impermeable layer 4 ′ between the mountain retaining walls 3 using the intermediate pile 5 for supporting the cut beam 7. A fulcrum that supports the artificial water-impermeable layer 4 ′ with respect to the lifting pressure A can be newly formed. Thereby, the distance between the fulcrums of the artificial impermeable layer 4 ′ is reduced, and the bending moment and shear force generated in the artificial impermeable layer 4 ′ due to the groundwater lifting pressure A can be reduced. Therefore, the artificial impermeable layer 4 ′ can be thinned and the strength can be reduced, and the construction period and cost for the artificial impermeable layer 4 ′ can be further reduced.

なお、中間杭5は切梁7の座屈防止の目的もあることから、山留壁3のスパンが大きい場合には山留壁3の間に複数本の中間杭5が配置される場合もある。例えば図15(a)のように山留壁3のスパンを3分割するように中間杭5を2本配置する場合、地下水の揚圧力Aにより人工不透水層4”に生じる曲げモーメントとせん断力の最大値はそれぞれ従来の1/9、1/3となる。この場合の人工不透水層4”の形状は、図2(b)等で説明した人工不透水層4と同様の形状が、各山留壁3と中間杭5の間および2本の中間杭5の間で計3つ形成されたものになる。   In addition, since the intermediate pile 5 also has the purpose of preventing buckling of the beam 7, when the span of the retaining wall 3 is large, a plurality of intermediate piles 5 may be disposed between the retaining walls 3. is there. For example, when two intermediate piles 5 are arranged so that the span of the mountain retaining wall 3 is divided into three as shown in FIG. 15 (a), the bending moment and shear force generated in the artificial impermeable layer 4 ″ by the groundwater lifting pressure A Are respectively 1/9 and 1/3. The shape of the artificial impermeable layer 4 ″ in this case is the same as the artificial impermeable layer 4 described with reference to FIG. A total of three are formed between each mountain retaining wall 3 and the intermediate pile 5 and between the two intermediate piles 5.

また、山留壁3の間の中間杭を全て支点として機能させる必要は無く、一部のみ支点として機能させてもよい。例えば山留壁3の間に3本の中間杭を設ける場合、図15(b)に示すように中央の中間杭5のみ本実施形態の構成を有するものとし、その他の中間杭は本実施形態の構成を持たず支点として機能しない、下端が人工不透水層4’に支持された通常の中間杭5’とできる。この場合の人工不透水層4’の形状は、図2(b)等で説明した人工不透水層4と同様の形状が、各山留壁3と中央の中間杭5の間で計2つ形成されたものになる。   Moreover, it is not necessary to make all the intermediate piles between the mountain retaining walls 3 function as fulcrums, and only a part may function as fulcrums. For example, when three intermediate piles are provided between the mountain retaining walls 3, only the middle intermediate pile 5 has the configuration of this embodiment as shown in FIG. 15 (b), and the other intermediate piles are the present embodiment. The lower end of the intermediate pile 5 ′ that does not function as a fulcrum and is supported by the artificial impermeable layer 4 ′ can be obtained. In this case, the shape of the artificial impermeable layer 4 ′ is the same as that of the artificial impermeable layer 4 described with reference to FIG. It will be formed.

一方、山留壁3の間の中間杭を全て通常の中間杭5’とする場合は、図15(c)のように山留壁3の間に第1の実施形態と同様の人工不透水層4を設ければよい。図15(c)は中間杭5’を山留壁3の間に1本配置する例であるが、中間杭5’を山留壁3の間に複数本配置する場合も同様である。   On the other hand, when all the intermediate piles between the mountain retaining walls 3 are normal intermediate piles 5 ', artificial impermeable water similar to that of the first embodiment is formed between the mountain retaining walls 3 as shown in FIG. 15 (c). The layer 4 may be provided. FIG. 15C is an example in which one intermediate pile 5 ′ is disposed between the mountain retaining walls 3, but the same applies when a plurality of intermediate piles 5 ′ are disposed between the mountain retaining walls 3.

なお本実施形態では、それぞれの例において、人工不透水層の形状が、図2(b)等で説明した人工不透水層4の形状を山留壁3と中間杭5の間、中間杭5の間、山留壁3の間のいずれかに設けたものとなっているが、これに代えて、その他の形状、例えば図6、7、9等で説明した人工不透水層4a、4b、4cの形状を山留壁3と中間杭5の間、中間杭5の間、山留壁3の間のいずれかに設けたものとしてもよい。通常の中間杭5’が有る場合についても、図15(b)〜(d)のように中間杭5’に関係なく山留壁3と中間杭5の間、中間杭5の間、山留壁3の間のいずれかに人工不透水層4a、4b、4cの形状を設ければ良い。なお、アーチ状の人工不透水層4c(図9参照)の場合、図15(d)に示すように中間杭5’の下端は人工不透水層4c上の地盤で支持されることになる。   In this embodiment, in each example, the shape of the artificial impermeable layer is the same as that of the artificial impermeable layer 4 described with reference to FIG. However, instead of this, other shapes such as the artificial impermeable layers 4a, 4b described in FIGS. The shape of 4c may be provided between the mountain retaining wall 3 and the intermediate pile 5, between the intermediate pile 5 and between the mountain retaining walls 3. Also in the case where there is a normal intermediate pile 5 ′, as shown in FIGS. 15B to 15D, regardless of the intermediate pile 5 ′, between the mountain retaining wall 3 and the intermediate pile 5, between the intermediate piles 5, What is necessary is just to provide the shape of the artificial water-impermeable layer 4a, 4b, 4c somewhere between the walls 3. In the case of the arch-shaped artificial impermeable layer 4c (see FIG. 9), the lower end of the intermediate pile 5 'is supported by the ground on the artificial impermeable layer 4c as shown in FIG. 15 (d).

また、支点を形成するための機構(支点形成機構)は中間杭5の人工不透水層4’以深の部分に限らず、図16のようにグラウンドアンカー8を用いてもよい。   Moreover, the mechanism (fulcrum formation mechanism) for forming a fulcrum is not limited to the portion of the intermediate pile 5 deeper than the artificial impermeable layer 4 ′, and a ground anchor 8 may be used as shown in FIG. 16.

この例では中間杭5の下部が人工不透水層4’を貫通せず中間杭5の下端が人工不透水層4’の内部にあるが、その代わりにグラウンドアンカー8の下端がコンクリート等の固定部6aで人工不透水層4’より深い位置の地盤2に固定され、グラウンドアンカー8の上端は中間杭5の頂部に固定されて緊張される。   In this example, the lower part of the intermediate pile 5 does not penetrate the artificial impermeable layer 4 ′ and the lower end of the intermediate pile 5 is inside the artificial impermeable layer 4 ′. Instead, the lower end of the ground anchor 8 is fixed with concrete or the like. It is fixed to the ground 2 at a position deeper than the artificial impermeable layer 4 ′ at the portion 6 a, and the upper end of the ground anchor 8 is fixed to the top of the intermediate pile 5 and is strained.

これによりグラウンドアンカー8と中間杭5を用いて人工不透水層4’をその下方の地盤2にアンカーすることができ、上記と同様、人工不透水層4’に地下水の揚圧力Aに対する抵抗力を与え、揚圧力Aに対し人工不透水層4’を支持する支点を中間杭5の位置で新たに形成することができる。またこの例ではグラウンドアンカー8の緊張力によって高い抵抗力を与えることができる。   As a result, the artificial impermeable layer 4 ′ can be anchored to the ground 2 below by using the ground anchor 8 and the intermediate pile 5, and the resistance to the groundwater lifting pressure A is applied to the artificial impermeable layer 4 ′ as described above. And a fulcrum supporting the artificial impermeable layer 4 ′ with respect to the lifting pressure A can be newly formed at the position of the intermediate pile 5. In this example, a high resistance can be given by the tension of the ground anchor 8.

さらに、図17(a)に示すように山留壁3、中間杭5および人工不透水層4’を構築した後、図17(b)に示すように山留壁3の間の地盤2の掘削と分流壁13のコンクリートを打設して図18(a)に示すように切梁7の設置を行う工程を上から順に繰り返すことで、図18(b)に示すように山留壁3の間の地盤2を床付け位置まで掘削してもよい。   Furthermore, after constructing the mountain retaining wall 3, the intermediate pile 5 and the artificial impermeable layer 4 ′ as shown in FIG. 17 (a), the ground 2 between the mountain retaining walls 3 as shown in FIG. 17 (b). By excavating and placing the concrete of the flow dividing wall 13 and installing the beam 7 as shown in FIG. 18 (a), the mountain retaining wall 3 as shown in FIG. 18 (b) is repeated in order from the top. The ground 2 may be excavated to the flooring position.

これにより、中間杭5を介して人工不透水層4’に上方からのコンクリート荷重を与えることができ、人工不透水層4’に地下水の揚圧力Aに対する抵抗力を与えて中間杭5の位置で人工不透水層4’に支点を形成することができる。なお、この例では中間杭5の下端が固定部6により人工不透水層4’内に固定される。   Thereby, the concrete load from above can be given to the artificial impermeable layer 4 ′ through the intermediate pile 5, and the resistance of the artificial water impermeable layer 4 ′ to the groundwater lifting pressure A is given to the position of the intermediate pile 5. Thus, a fulcrum can be formed on the artificial impermeable layer 4 ′. In this example, the lower end of the intermediate pile 5 is fixed in the artificial impermeable layer 4 ′ by the fixing portion 6.

ポンプ室はその後図19に示すように構築されるが、この例では本設の分流壁13が逆巻き工法で先行して構築されるので、ここではポンプ室1bの底版11と側壁12のみ構築すればよい。また前記と異なり、中間杭5は撤去せず残置される。   The pump chamber is then constructed as shown in FIG. 19, but in this example, since the main branch wall 13 is constructed in advance by the reverse winding method, only the bottom plate 11 and the side wall 12 of the pump chamber 1b are constructed here. That's fine. Also, unlike the above, the intermediate pile 5 is left without being removed.

この例では地上部分で支点形成機構を設けることができるので施工も容易であり、コンクリートを逆巻き工法で施工しポンプ室1bの本設の分流壁13として利用することでポンプ室1bの構築にかかる工期の延長も防止できる。   In this example, since a fulcrum formation mechanism can be provided on the ground part, the construction is easy, and the construction of the pump chamber 1b is performed by constructing the concrete by the reverse winding method and using it as the main branch wall 13 of the pump chamber 1b. Extension of the work period can also be prevented.

以上、添付図面を参照して、本発明の好適な実施形態について説明したが、本発明は係る例に限定されない。当業者であれば、本願で開示した技術的思想の範疇内において、各種の変更例または修正例に想到し得ることは明らかであり、それらについても当然に本発明の技術的範囲に属するものと了解される。   The preferred embodiments of the present invention have been described above with reference to the accompanying drawings, but the present invention is not limited to such examples. It will be apparent to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea disclosed in the present application, and these are naturally within the technical scope of the present invention. Understood.

1、1a、1b:ポンプ室
2:地盤
3:山留壁
4、4’、4”、4a、4b、4c:人工不透水層
5:中間杭
6、6a:固定部
7:切梁
8:グラウンドアンカー
10:ボックスカルバート
11、110:底版
12、120:側壁
13:分流壁
41、43、44、45、46:傾斜面
42:水平面
130:中壁
140:頂版
411:段部
DESCRIPTION OF SYMBOLS 1, 1a, 1b: Pump chamber 2: Ground 3: Mountain retaining wall 4, 4 ', 4 ", 4a, 4b, 4c: Artificial impermeable layer 5: Intermediate pile 6, 6a: Fixed part 7: Cut beam 8: Ground anchor 10: Box culvert 11, 110: Bottom plate 12, 120: Side wall 13: Dividing wall 41, 43, 44, 45, 46: Inclined surface 42: Horizontal surface 130: Middle wall 140: Top plate 411: Stepped portion

Claims (7)

地盤を固化材により改良して形成された人工不透水層を有する地盤改良構造であって、
前記人工不透水層は、複数の支点において地下水の揚圧力に対して支持され、
前記人工不透水層の少なくとも上面と下面のいずれかは、前記支点の間の中間部における高さと、前記支点の位置における高さの違いにより、上方または下方に凸状に形成されることを特徴とする地盤改良構造。
A ground improvement structure having an artificial impermeable layer formed by improving the ground with a solidifying material,
The artificial impermeable layer is supported against groundwater lifting pressure at a plurality of fulcrums,
At least one of the upper surface and the lower surface of the artificial impermeable layer is formed in a convex shape upward or downward due to a difference in height at an intermediate portion between the fulcrums and at a position of the fulcrum. Improved ground structure.
前記人工不透水層は、前記支点の間の中間部における厚さと、前記支点の位置における厚さが異なることを特徴とする請求項1に記載の地盤改良構造。   The ground improvement structure according to claim 1, wherein the artificial impermeable layer has a thickness at an intermediate portion between the fulcrums and a thickness at the position of the fulcrum. 前記人工不透水層は、前記支点の間の中間部における厚さが、前記支点の位置における厚さより小さいことを特徴とする請求項2記載の地盤改良構造。   The ground improvement structure according to claim 2, wherein the artificial impermeable layer has a thickness at an intermediate portion between the fulcrums smaller than a thickness at the position of the fulcrum. 前記人工不透水層は、前記支点の間の中間部における厚さが、前記支点の位置における厚さより大きいことを特徴とする請求項2記載の地盤改良構造。   The ground improvement structure according to claim 2, wherein the artificial impermeable layer has a thickness at an intermediate portion between the fulcrums larger than a thickness at the position of the fulcrum. 前記人工不透水層の上面および下面は、下方に凸となった形状を有し、前記支点の間の中間部における高さが前記支点の位置における高さよりも下にあることを特徴とする請求項1記載の地盤改良構造。   The upper surface and the lower surface of the artificial impermeable layer have a shape that protrudes downward, and a height at an intermediate portion between the fulcrums is lower than a height at the position of the fulcrum. Item 1. The ground improvement structure according to item 1. 前記人工不透水層の上面と下面の少なくともいずれかは、水平方向に対し傾斜した傾斜面を有し、前記傾斜面は複数の段部により段状に形成されることを特徴とする請求項1から請求項5のいずれかに記載の地盤改良構造。   The at least one of an upper surface and a lower surface of the artificial impermeable layer has an inclined surface inclined with respect to a horizontal direction, and the inclined surface is formed in a step shape by a plurality of step portions. The ground improvement structure according to claim 5. 地盤を固化材により改良して人工不透水層を設ける工程(a)と、
前記人工不透水層の上方の地盤の掘削を行う工程(b)と、
を有し、
前記人工不透水層は、複数の支点において地下水の揚圧力に対して支持され、
前記人工不透水層の少なくとも上面と下面のいずれかは、前記支点の間の中間部における高さと、前記支点の位置における高さの違いにより、上方または下方に凸状に形成されることを特徴とする掘削方法。
(A) providing an artificial impermeable layer by improving the ground with a solidifying material;
A step (b) of excavating the ground above the artificial impermeable layer;
Have
The artificial impermeable layer is supported against groundwater lifting pressure at a plurality of fulcrums,
At least one of the upper surface and the lower surface of the artificial impermeable layer is formed in a convex shape upward or downward due to a difference in height at an intermediate portion between the fulcrums and at a position of the fulcrum. And drilling method.
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Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5253522A (en) * 1975-10-29 1977-04-30 Shimizu Constr Co Ltd Underground tank for storage of low temperature liquidized gas
JPS5929900A (en) * 1982-08-09 1984-02-17 Taisei Corp Underground tank
JPH04114888A (en) * 1990-08-31 1992-04-15 Tokyo Gas Co Ltd Underground storage structure
JPH04182509A (en) * 1990-11-16 1992-06-30 Kawasaki Steel Corp Land slide protection structure
JPH0641990A (en) * 1992-07-22 1994-02-15 Taisei Corp Ground improving method for direct under existing structure
JPH06116974A (en) * 1992-10-09 1994-04-26 Taisei Corp Underground tank
JPH11200393A (en) * 1998-01-08 1999-07-27 Kajima Corp Underground structure and construction method therefor
JPH11247174A (en) * 1998-02-27 1999-09-14 Takenaka Komuten Co Ltd Groundwater collecting method in underground water isolation method
JP2000045264A (en) * 1998-07-31 2000-02-15 Chem Grouting Co Ltd Construction method of hydraulic pressure proofing board
JP2001072181A (en) * 1999-09-07 2001-03-21 Taisei Corp Structure of underground tank
JP2001279659A (en) * 2000-03-31 2001-10-10 Taisei Corp Ground improvement method between earth retaining walls
JP2002047676A (en) * 2000-08-02 2002-02-15 Hanshin Expressway Public Corp Buoyancy preventing structure and its construction method
JP2003171949A (en) * 2001-12-04 2003-06-20 Tobishima Corp Excavating bottom surface-stabilizing construction method and underground building construction method
JP2007224645A (en) * 2006-02-24 2007-09-06 Land 4 International Kk Method of constructing improved slope ground in execution of soil improvement, and multiple soil improving machine
JP2013117479A (en) * 2011-12-05 2013-06-13 Michiko Yamato Disposal method of soil, sludge or incineration ash contaminated by radioactive substance

Family Cites Families (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP4118694B2 (en) 2002-01-15 2008-07-16 ジャパンパイル株式会社 Ground improvement method

Patent Citations (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5253522A (en) * 1975-10-29 1977-04-30 Shimizu Constr Co Ltd Underground tank for storage of low temperature liquidized gas
JPS5929900A (en) * 1982-08-09 1984-02-17 Taisei Corp Underground tank
JPH04114888A (en) * 1990-08-31 1992-04-15 Tokyo Gas Co Ltd Underground storage structure
JPH04182509A (en) * 1990-11-16 1992-06-30 Kawasaki Steel Corp Land slide protection structure
JPH0641990A (en) * 1992-07-22 1994-02-15 Taisei Corp Ground improving method for direct under existing structure
JPH06116974A (en) * 1992-10-09 1994-04-26 Taisei Corp Underground tank
JPH11200393A (en) * 1998-01-08 1999-07-27 Kajima Corp Underground structure and construction method therefor
JPH11247174A (en) * 1998-02-27 1999-09-14 Takenaka Komuten Co Ltd Groundwater collecting method in underground water isolation method
JP2000045264A (en) * 1998-07-31 2000-02-15 Chem Grouting Co Ltd Construction method of hydraulic pressure proofing board
JP2001072181A (en) * 1999-09-07 2001-03-21 Taisei Corp Structure of underground tank
JP2001279659A (en) * 2000-03-31 2001-10-10 Taisei Corp Ground improvement method between earth retaining walls
JP2002047676A (en) * 2000-08-02 2002-02-15 Hanshin Expressway Public Corp Buoyancy preventing structure and its construction method
JP2003171949A (en) * 2001-12-04 2003-06-20 Tobishima Corp Excavating bottom surface-stabilizing construction method and underground building construction method
JP2007224645A (en) * 2006-02-24 2007-09-06 Land 4 International Kk Method of constructing improved slope ground in execution of soil improvement, and multiple soil improving machine
JP2013117479A (en) * 2011-12-05 2013-06-13 Michiko Yamato Disposal method of soil, sludge or incineration ash contaminated by radioactive substance

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