JP6587921B2 - Freezing pipe construction method - Google Patents

Freezing pipe construction method Download PDF

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JP6587921B2
JP6587921B2 JP2015239993A JP2015239993A JP6587921B2 JP 6587921 B2 JP6587921 B2 JP 6587921B2 JP 2015239993 A JP2015239993 A JP 2015239993A JP 2015239993 A JP2015239993 A JP 2015239993A JP 6587921 B2 JP6587921 B2 JP 6587921B2
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outer casing
hole
frozen
freezing
water
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JP2017106210A (en
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吉田　輝
輝 吉田
永谷　英基
英基 永谷
博光 木田
博光 木田
尚 高村
尚 高村
一成 佐藤
一成 佐藤
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Kajima Corp
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Description

本発明は、凍結管の施工方法に関するものである。   The present invention relates to a method for constructing a freezing tube.

従来、透水性のある地盤に凍結工法を利用して立坑を構築する場合、立坑の底部根切り面付近以下の範囲に予め薬液注入による地盤改良を行った後、凍土壁を造成し、凍土壁内側の地盤を掘削する方法があった（例えば、特許文献１参照）。   Conventionally, when constructing a shaft using the freezing method on water-permeable ground, after improving the ground by injecting a chemical solution in the area below the bottom root cutting surface of the shaft in advance, a frozen soil wall is created and the frozen soil wall There has been a method of excavating the inner ground (see, for example, Patent Document 1).

また、トンネルを掘削する際に、先行して作業用トンネルを構築し、作業用トンネルを用いて、本トンネルの掘削部に沿った領域に予め薬液注入により強度増加領域を形成した後、強度増加領域を含む領域に凍結工法により凍結領域を形成し、本トンネルを掘削する方法があった（例えば、特許文献２参照）。   In addition, when excavating the tunnel, a working tunnel was constructed in advance, and using the working tunnel, a strength increasing region was formed in advance in the region along the excavation part of this tunnel by chemical injection, and then the strength was increased. There has been a method of excavating the tunnel by forming a frozen region in a region including the region by a freezing method (see, for example, Patent Document 2).

他に、凍結による地盤***や解凍後の地盤沈下を抑制するために、予め高吸水性材料の水溶液や水懸濁液を高圧ジェット水と共に改良すべき地盤中に注入した後、地盤を凍結させる方法があった（例えば、特許文献３参照）。   In addition, in order to suppress ground uplift due to freezing or ground subsidence after thawing, an aqueous solution or water suspension of a superabsorbent material is injected into the ground to be improved together with high-pressure jet water, and then the ground is frozen. There was a method (for example, refer patent document 3).

特開昭６１−６０９９５号公報JP-A 61-60995 特開平３−１３２５９２号公報Japanese Patent Laid-Open No. 3-132592 特開平７−７１１８３号公報JP-A-7-71183

上述した各方法によれば、薬液等による地盤改良と凍結工法とを併用することにより、湧水による凍土壁の融解や、地下水の流れによる凍結の阻害を防止することが可能である。しかし、いずれの方法も広範囲にわたって地盤改良を行うため、効率的でなかった。また、長期間にわたって凍土による止水壁の運用を続けるような場合は想定されていなかった。   According to each method described above, it is possible to prevent the frozen soil wall from being melted by the spring water and freezing inhibition due to the flow of the groundwater by using the ground improvement by the chemical solution and the freezing method in combination. However, each method is not efficient because ground improvement is performed over a wide range. In addition, it was not assumed that the operation of the water barrier with frozen soil would be continued for a long period of time.

本発明は、前述した問題点に鑑みてなされたもので、その目的とすることは、凍結に支障となる地盤中の隙間や通水層を凍結管の施工中に効率良く目詰まりさせることができ、凍結外管の破損時に迅速に補修できる凍結管の施工方法を提供することである。   The present invention has been made in view of the above-described problems, and the object of the present invention is to efficiently clog gaps and water-permeable layers in the ground that interfere with freezing during construction of the freezing pipe. It is possible to provide a construction method of a frozen pipe that can be repaired quickly when a frozen outer pipe is broken.

前述した目的を達成するために本発明は、流動性固化材を外ケーシングの下方に所定の圧力で注入しつつ、前記外ケーシングを用いて地盤に孔を掘削し、前記孔の壁面と前記外ケーシングの外周面との間および前記外ケーシングの内部に前記流動性固化材を充填し、前記孔の周囲の通水層に前記流動性固化材を浸透させる工程ａと、前記外ケーシング内に、凍結外管と凍結内管とからなる凍結管を挿入し、前記孔の周囲に凍結土を構築する工程ｂと、を具備し、前記工程ａでは、前記孔を前記通水層の下方まで掘削することを特徴とする凍結管の施工方法である。
第２の発明は、流動性固化材を外ケーシングの下方に所定の圧力で注入しつつ、前記外ケーシングを用いて地盤に孔を掘削し、前記孔の壁面と前記外ケーシングの外周面との間および前記外ケーシングの内部に前記流動性固化材を充填し、前記孔の周囲の通水層に前記流動性固化材を浸透させる工程ａと、前記外ケーシング内に、凍結外管と凍結内管とからなる凍結管を挿入し、前記孔の周囲に凍結土を構築する工程ｂと、を具備し、前記工程ｂで、前記凍結外管からの冷却液の漏出を検知した後、前記凍結管から冷却液を抜き取り、前記凍結外管と前記凍結内管との間に追加凍結外管を設置する工程ｄをさらに具備することを特徴とする凍結管の施工方法である。
第３の発明は、流動性固化材を外ケーシングの下方に所定の圧力で注入しつつ、前記外ケーシングを用いて地盤に孔を掘削し、前記孔の壁面と前記外ケーシングの外周面との間および前記外ケーシングの内部に前記流動性固化材を充填し、前記孔の周囲の通水層に前記流動性固化材を浸透させる工程ａと、前記外ケーシング内に、凍結外管と凍結内管とからなる凍結管を挿入し、前記孔の周囲に凍結土を構築する工程ｂと、を具備し、前記工程ａで、前記通水層の上方の地盤および／または前記通水層の下方の地盤では、前記流動性固化材の代わりに泥水を注入して前記孔を掘削することを特徴とする凍結管の施工方法である。 In order to achieve the above-mentioned object, the present invention excavates a hole in the ground using the outer casing while injecting a fluid solidifying material below the outer casing at a predetermined pressure, and the wall surface of the hole and the outer Step a in which the fluidized solidification material is filled between the outer peripheral surface of the casing and the inside of the outer casing, and the fluidized solidification material is infiltrated into the water-permeable layer around the hole, and in the outer casing, Inserting a freezing pipe composed of an outer freezing pipe and a freezing inner pipe, and constructing a frozen soil around the hole, and in the step a, excavating the hole to below the water-permeable layer It is the construction method of the freezing pipe characterized by doing .
According to a second aspect of the present invention, a fluid solidifying material is injected below the outer casing at a predetermined pressure, a hole is excavated in the ground using the outer casing, and the wall surface of the hole and the outer peripheral surface of the outer casing are Filling the inside of the outer casing with the fluidized solidifying material and allowing the fluidized solidifying material to permeate the water-permeable layer around the hole; and in the outer casing, the frozen outer pipe and the frozen inner Inserting a freezing tube comprising a tube and constructing frozen soil around the hole, and in step b, after detecting leakage of the coolant from the freezing outer tube, the freezing A cryopipe construction method, further comprising a step (d) of extracting a coolant from the pipe and installing an additional freeze outer pipe between the frozen outer pipe and the frozen inner pipe .
According to a third aspect of the present invention, a fluid solidifying material is injected below the outer casing at a predetermined pressure, a hole is excavated in the ground using the outer casing, and the wall surface of the hole and the outer peripheral surface of the outer casing are Filling the inside of the outer casing with the fluidized solidifying material and allowing the fluidized solidifying material to permeate the water-permeable layer around the hole; and in the outer casing, the frozen outer pipe and the frozen inner Inserting a freezing pipe composed of a pipe and constructing frozen soil around the hole, and in the step a, the ground above the water-permeable layer and / or below the water-permeable layer In this ground, the frozen pipe construction method is characterized in that mud water is injected instead of the fluidized solidified material to excavate the hole.

本発明では、前記工程ａと前記工程ｂとの間に、前記外ケーシングの下端部付近を止水部材で閉塞し、前記外ケーシング内の前記流動性固化材を抜き取る工程ｃをさらに具備してもよい。
この場合、前記工程ｂで、前記外ケーシングの内周面と前記凍結外管の外周面との間に熱伝導性を有する充填材を充填することが望ましい。 In the present invention, the method further includes a step c between the step a and the step b, in which the vicinity of the lower end portion of the outer casing is closed with a water stop member and the fluidized solidified material in the outer casing is extracted. Also good.
In this case, it is preferable that a filler having thermal conductivity is filled between the inner peripheral surface of the outer casing and the outer peripheral surface of the frozen outer tube in the step b.

前記工程ｄで、前記凍結外管の内周面と前記追加凍結外管の外周面との間に熱伝導性を有する充填材を充填することが望ましい。   In the step d, it is preferable that a filler having thermal conductivity is filled between the inner peripheral surface of the frozen outer tube and the outer peripheral surface of the additional frozen outer tube.

本発明では、前記工程ａで、前記通水層の上方の地盤および／または前記通水層の下方の地盤では、前記流動性固化材の代わりに泥水を注入して前記孔を掘削してもよい。   In the present invention, in the step a, in the ground above the water flow layer and / or the ground below the water flow layer, mud is injected instead of the fluidized solidifying material to excavate the hole. Good.

本発明によれば、凍結に支障となる地盤中の隙間や通水層を凍結管の施工中に効率良く目詰まりさせることができ、凍結外管の破損時に迅速に補修できる凍結管の施工方法を提供できる。   According to the present invention, a method for constructing a frozen pipe that can efficiently clog gaps and water passages in the ground that hinder freezing during construction of the frozen pipe, and that can be quickly repaired when the frozen outer pipe is broken. Can provide.

地盤１に孔５を掘削する工程を示す図The figure which shows the process of excavating the hole 5 in the ground 1 孔５の周囲に凍結土３３を形成する工程を示す図The figure which shows the process of forming the frozen soil 33 around the hole 5 凍結土３３によって形成された止水壁５１の垂直方向の断面図Cross section in the vertical direction of the water blocking wall 51 formed by the frozen soil 33 凍結土３３によって形成された止水壁５１の水平方向の断面図Horizontal cross-sectional view of the water blocking wall 51 formed by the frozen soil 33 凍結外管２３の補修を行う工程を示す図The figure which shows the process of repairing the frozen outer tube 23

以下、図面に基づいて、本発明の第１の実施の形態を詳細に説明する。図１は、地盤１に孔５を掘削する工程を示す図である。図１（ａ）は、通水層６の上方の地盤１を掘削している状態を、図１（ｂ）は、通水層６を掘削している状態を、図１（ｃ）は、通水層６の下方の地盤１を掘削している状態を示す。   Hereinafter, a first embodiment of the present invention will be described in detail with reference to the drawings. FIG. 1 is a diagram showing a process of excavating a hole 5 in the ground 1. FIG. 1A shows a state in which the ground 1 above the water flow layer 6 is excavated, FIG. 1B shows a state in which the water flow layer 6 is excavated, and FIG. The state which excavates the ground 1 below the water flow layer 6 is shown.

図１に示すように、外ケーシング３を用いて地盤１に孔５を掘削するには、まず、図１（ａ）に示すように、泥水７を矢印Ａに示すように外ケーシング３の下方に所定の圧力で注入しつつ、外ケーシング３の下端のビット４を用いて、通水層６の上方の地盤１に孔５を掘削する。孔５の径は、例えば１０〜２０ｃｍ程度とする。   As shown in FIG. 1, in order to excavate the hole 5 in the ground 1 using the outer casing 3, first, as shown in FIG. The hole 5 is excavated in the ground 1 above the water-permeable layer 6 using the bit 4 at the lower end of the outer casing 3 while being injected at a predetermined pressure. The diameter of the hole 5 is, for example, about 10 to 20 cm.

続いて、図１（ｂ）に示すように、流動性固化材であるＣＢ（セメントベントナイト）改良泥水１３を矢印Ｂに示すように外ケーシング３の下方に所定の圧力で注入しつつ、通水層６に孔５を掘削する。このとき、ＣＢ改良泥水１３が外ケーシング３の外側に回り込み、孔５の壁面９と外ケーシング３の外周面１１との間に充填される。また、外ケーシング３の外側に回り込んだＣＢ改良泥水１３が孔５の壁面９から通水層６に浸透し、通水層６の一部に改良層１５が形成される。   Subsequently, as shown in FIG. 1 (b), CB (cement bentonite) improved muddy water 13 which is a fluidized solidifying material is injected at a predetermined pressure below the outer casing 3 as indicated by an arrow B, and water is passed through. Drill holes 5 in the layer 6. At this time, the CB improved muddy water 13 goes around the outside of the outer casing 3 and is filled between the wall surface 9 of the hole 5 and the outer peripheral surface 11 of the outer casing 3. Further, the CB improved muddy water 13 that has entered the outside of the outer casing 3 permeates into the water passage layer 6 from the wall surface 9 of the hole 5, and the improvement layer 15 is formed in a part of the water passage layer 6.

さらに、図１（ｃ）に示すように、ＣＢ改良泥水１３を矢印Ｃに示すように外ケーシング３の下方に所定の圧力で注入しつつ、通水層６の下方の地盤１に孔５を掘削する。このとき、引き続き、ＣＢ改良泥水１３が外ケーシング３の外側に回り込み、孔５の壁面９と外ケーシング３の外周面１１との間に充填される。また、ＣＢ改良泥水１３が孔５の壁面９から通水層６に浸透し、改良層１５が形成される。   Further, as shown in FIG. 1 (c), a hole 5 is formed in the ground 1 below the water passage layer 6 while injecting the CB improved mud water 13 at a predetermined pressure below the outer casing 3 as indicated by an arrow C. Excavate. At this time, the CB improved muddy water 13 continues around the outside of the outer casing 3 and is filled between the wall surface 9 of the hole 5 and the outer peripheral surface 11 of the outer casing 3. Further, the CB improved muddy water 13 penetrates from the wall surface 9 of the hole 5 into the water passing layer 6, and the improved layer 15 is formed.

図２は、孔５の周囲に凍結土３３を形成する工程を示す図である。図２（ａ）は、孔５の掘削が完了した状態を、図２（ｂ）は、止水部材１９を設置した状態を、図２（ｃ）は、外ケーシング３内に凍結管２９を挿入した状態を、図２（ｄ）は、孔５の周囲に凍結土３３を構築した状態を示す図である。   FIG. 2 is a diagram illustrating a process of forming the frozen soil 33 around the hole 5. 2A shows a state where the excavation of the hole 5 is completed, FIG. 2B shows a state where the water stop member 19 is installed, and FIG. 2C shows a state where the freezing pipe 29 is installed in the outer casing 3. FIG. 2 (d) is a diagram showing a state in which the frozen soil 33 is constructed around the hole 5.

図２に示す工程では、図１（ｃ）に示す状態から、地盤１をさらに掘削し、図２（ａ）に示すように、所定の深さまで孔５を掘削する。そして、ＣＢ改良泥水１３が所定の注入量に達したところで、孔５の全長に亘って孔５の壁面９と外ケーシング３の外周面１１との間にＣＢ改良泥水１３が充填され、また、孔５の周囲の通水層６（図１（ａ））にＣＢ改良泥水１３が十分に浸透して目詰まりし改良層１５が形成されたと判断して、ＣＢ改良泥水１３の注入を終了し、掘削を完了する。外ケーシング３の内部には、ＣＢ改良泥水１３が充填される。   In the process shown in FIG. 2, the ground 1 is further excavated from the state shown in FIG. 1 (c), and the hole 5 is excavated to a predetermined depth as shown in FIG. 2 (a). Then, when the CB improved muddy water 13 reaches a predetermined injection amount, the CB improved muddy water 13 is filled between the wall surface 9 of the hole 5 and the outer peripheral surface 11 of the outer casing 3 over the entire length of the hole 5, It is judged that the CB improved mud water 13 has sufficiently penetrated into the water-permeable layer 6 (FIG. 1 (a)) around the hole 5 and clogged to form the improved layer 15, and the injection of the CB improved mud water 13 is finished. Complete drilling. The outer casing 3 is filled with CB improved mud water 13.

ＣＢ改良泥水１３の注入量は、注入範囲（直径および層厚）と間隙率とから算出する。なお、ＣＢ改良泥水１３が外ケーシング３と孔５の間から地上に流出が確認された場合、または図示しない観測井から地表面へのＣＢ改良泥水１３の流出が確認された場合、注入を継続しても通水層６には浸透しないため、所定の注入量に達していなくてもＣＢ改良泥水１３の注入を終了する。   The injection amount of the CB improved mud water 13 is calculated from the injection range (diameter and layer thickness) and the porosity. In addition, when the outflow of the CB improved mud water 13 from the space between the outer casing 3 and the hole 5 is confirmed or when the outflow of the CB improved muddy water 13 from the observation well (not shown) to the ground surface is confirmed, the injection is continued. Even if it does not permeate into the water flow layer 6, the injection of the CB improved mud water 13 is terminated even if the predetermined injection amount has not been reached.

掘削完了後、図２（ｂ）に示すように、外ケーシング３内に地表側からロッド１７を介して止水部材１９を外ケーシング３に挿入し、止水部材１９を外ケーシング３の下端部付近の内周面２１に係止して、外ケーシング３の下端部付近を止水部材１９で閉塞する。止水部材１９は、例えばゴム製等とする。   After completion of excavation, as shown in FIG. 2 (b), the water stop member 19 is inserted into the outer casing 3 through the rod 17 from the surface side into the outer casing 3, and the water stop member 19 is inserted into the lower end of the outer casing 3. The outer peripheral surface 21 is engaged with the inner peripheral surface 21 in the vicinity, and the vicinity of the lower end portion of the outer casing 3 is closed with the water stop member 19. The water stop member 19 is made of, for example, rubber.

その後、図２（ｃ）に示すように、外ケーシング３内のＣＢ改良泥水１３を抜き取り、ロッド１７を止水部材１９との接続部を残して撤去する。そして、外ケーシング３内に、凍結外管２３と凍結内管２４とからなる凍結管２９を挿入し、外ケーシング３の内周面２１と凍結外管２３の外周面２５との間に、熱伝導性を有する充填材である防錆材２７を充填する。防錆材２７は、例えば水ガラスである。   Thereafter, as shown in FIG. 2 (c), the CB improved muddy water 13 in the outer casing 3 is extracted, and the rod 17 is removed leaving a connection portion with the water stop member 19. Then, a freezing tube 29 composed of the frozen outer tube 23 and the frozen inner tube 24 is inserted into the outer casing 3, and heat is applied between the inner peripheral surface 21 of the outer casing 3 and the outer peripheral surface 25 of the frozen outer tube 23. A rust preventive material 27 which is a conductive filler is filled. The rust preventive material 27 is, for example, water glass.

次に、図２（ｄ）に示すように、凍結管２９内に冷却液３１を充填する。そして、図示しない冷却液供給機構を用いて、冷却液３１を凍結内管２４から凍結外管２３へ矢印Ｄに示すように循環させ、孔５の周囲に凍結土３３を構築する。   Next, as shown in FIG. 2 (d), the cooling liquid 31 is filled into the freezing tube 29. Then, using a coolant supply mechanism (not shown), the coolant 31 is circulated from the frozen inner tube 24 to the frozen outer tube 23 as shown by the arrow D, and the frozen soil 33 is constructed around the hole 5.

図３は、凍結土３３によって形成された止水壁５１の垂直方向の断面図、図４は、凍結土３３によって形成された止水壁５１の水平方向の断面図である。図４は、図３に示す矢印Ｅ−Ｅによる断面図である。   FIG. 3 is a vertical sectional view of the water blocking wall 51 formed by the frozen soil 33, and FIG. 4 is a horizontal sectional view of the water blocking wall 51 formed by the frozen soil 33. 4 is a cross-sectional view taken along arrows EE shown in FIG.

図３、図４に示すように、地盤１に所定の間隔で掘削した複数の孔５に凍結管２９を挿入し、凍結土３３を構築することにより、孔５を中心に略円柱状に形成される凍結土３３が連結し、止水壁５１が形成される。孔５同士の間隔は、例えば１ｍ程度とする。   As shown in FIG. 3 and FIG. 4, the frozen pipe 29 is inserted into the plurality of holes 5 excavated in the ground 1 at a predetermined interval, and the frozen soil 33 is constructed to form a substantially cylindrical shape around the hole 5. The frozen soil 33 is connected to form a water blocking wall 51. The interval between the holes 5 is, for example, about 1 m.

地盤１の通水層６（図１）では、図４に示す矢印Ｆの方向の地下水の流れが存在するが、地盤１に孔５を掘削する段階で、孔５の壁面９と外ケーシング３の外周面１１との間にＣＢ改良泥水１３が充填され、通水層６にＣＢ改良泥水１３が浸透して改良層１５が形成されているため、孔５の壁面９と外ケーシング３の外周面１１との間や通水層６を通って、止水壁５１の上流側から下流側に水が流れることはない。   In the water flow layer 6 (FIG. 1) of the ground 1, there is a flow of groundwater in the direction of arrow F shown in FIG. 4, but when the hole 5 is excavated in the ground 1, the wall surface 9 of the hole 5 and the outer casing 3 Since the CB improved muddy water 13 is filled between the outer peripheral surface 11 and the CB improved muddy water 13 penetrates into the water passage layer 6 to form the improved layer 15, the wall surface 9 of the hole 5 and the outer periphery of the outer casing 3 are formed. Water does not flow from the upstream side to the downstream side of the water blocking wall 51 between the surface 11 and the water passage layer 6.

このように、第１の実施の形態では、凍結管２９を設置するための削孔時に、孔５の壁面９と外ケーシング３の外周面１１との間および外ケーシング３の内部にＣＢ改良泥水１３を充填し、孔５の周囲の通水層６にＣＢ改良泥水１３を浸透させて改良層１５を形成する。これにより、凍結管２９の施工過程で、孔５の壁面９と外ケーシング３の外周面１１との間を閉塞し、通水層６の領域を効率良く改質することができ、凍結に支障となる水の流れを阻止することができる。   As described above, in the first embodiment, the CB improved muddy water is formed between the wall surface 9 of the hole 5 and the outer peripheral surface 11 of the outer casing 3 and inside the outer casing 3 when drilling for installing the freezing pipe 29. 13 is filled, and the CB improved mud water 13 is infiltrated into the water passing layer 6 around the hole 5 to form the improved layer 15. Thereby, in the construction process of the freezing pipe 29, the space between the wall surface 9 of the hole 5 and the outer peripheral surface 11 of the outer casing 3 can be closed, and the region of the water flow layer 6 can be efficiently reformed, which hinders freezing. Can be prevented from flowing.

なお、第１の実施の形態では、孔５を掘削する際に流動性固化材としてＣＢ改良泥水１３を用いたが、流動性固化材の種類はこれに限らない。例えば、水ガラス等の緩結タイプの薬液や、微粒子セメント、超微粒子セメント、極超微粒子セメント等を用いた改良泥水を用いてもよい。   In the first embodiment, the CB improved muddy water 13 is used as the fluidized solidifying material when excavating the hole 5, but the type of the fluidized solidified material is not limited thereto. For example, a loosely-cured chemical solution such as water glass, or improved muddy water using fine particle cement, ultrafine particle cement, ultrafine particle cement, or the like may be used.

また、孔５を掘削する際に、通水層６の上方の地盤１の掘削に流動性固化材のかわりに泥水を用いたが、通水層６の下方の地盤１の掘削にも泥水を用いてよい。   Moreover, when excavating the hole 5, mud was used for excavating the ground 1 above the water layer 6 instead of the fluidized solidifying material, but mud was also used for excavating the ground 1 below the water layer 6. May be used.

さらに、外ケーシング３の内周面２１と凍結外管２３の外周面２５との間の充填材として防錆材２７を充填したが、この充填材は防錆剤に限らず、潤滑性を有し熱伝導性を有するものであればよい。   Further, although a rust preventive material 27 is filled as a filler between the inner peripheral surface 21 of the outer casing 3 and the outer peripheral surface 25 of the frozen outer tube 23, this filler is not limited to a rust preventive agent and has lubricity. Any material having thermal conductivity may be used.

次に、第２の実施の形態について説明する。図５は、凍結外管２３の補修を行う工程を示す図である。図５（ａ）は、凍結管２９を用いて地盤の凍結を維持している状態を示す図、図５（ｂ）は、凍結管２９内の冷却液３１を抜き取った状態を示す図、図５（ｃ）は、追加凍結外管３９を設置した状態を示す図である。   Next, a second embodiment will be described. FIG. 5 is a diagram illustrating a process of repairing the frozen outer tube 23. FIG. 5A is a view showing a state in which the ground is kept frozen using the freezing tube 29, and FIG. 5B is a view showing a state in which the cooling liquid 31 in the freezing tube 29 is extracted. FIG. 5C is a view showing a state in which the additional freezing outer tube 39 is installed.

第２の実施の形態では、まず、第１の実施の形態と同様にして、図５（ａ）に示すように地盤１に孔５を掘削し、孔５の壁面９と外ケーシング３の外周面１１との間にＣＢ改良泥水３７を充填し、孔５の周囲の通水層６（図１（ａ））にＣＢ改良泥水３７を十分に浸透させて目詰まりさせ、外ケーシング３の内部にＣＢ改良泥水３７を充填する。次に、外ケーシング３内に、凍結外管２３と凍結内管２４とからなる凍結管２９を挿入し、凍結管２９内に冷却液３１を充填する。そして、図示しない冷却液供給機構を用いて、凍結管２９内で冷却液３１を循環させて孔５の周囲に凍結土３３を構築する。凍結維持段階では、ＣＢ改良泥水３７に埋設した凍結管２９を用いて、凍結土３３を長期に亘って維持する。   In the second embodiment, first, as in the first embodiment, a hole 5 is excavated in the ground 1 as shown in FIG. 5 (a), and the wall surface 9 of the hole 5 and the outer periphery of the outer casing 3 are excavated. The CB improved mud water 37 is filled between the surface 11 and the water passing layer 6 (FIG. 1A) around the hole 5 is sufficiently permeated to clog the CB improved mud water 37, and the inside of the outer casing 3. Is filled with CB improved mud water 37. Next, a freezing tube 29 composed of a freezing outer tube 23 and a freezing inner tube 24 is inserted into the outer casing 3, and the freezing tube 29 is filled with a cooling liquid 31. Then, using a coolant supply mechanism (not shown), the coolant 31 is circulated in the freezing pipe 29 to construct the frozen soil 33 around the hole 5. In the freezing maintenance stage, the frozen soil 33 is maintained for a long time using the freezing pipe 29 embedded in the CB improved mud water 37.

凍結維持段階では、凍結管２９を長期間使用するため、図５（ｂ）に示すように、凍結外管２３に欠損部３５が生じ、凍結外管２３から少量の冷却液３１の漏出を検知する場合がある。凍結外管２３からの冷却液３１の漏出を検知した場合、図５（ｂ）に示すように、凍結管２９から冷却液３１を抜き取る。なお、凍結外管２３の外周面２５と外ケーシング３の内周面２１との間にはＣＢ改良泥水３７が充填されているため、欠損部３５が生じても冷却液３１が大量に漏出することはない。   In the freezing maintenance stage, since the freezing tube 29 is used for a long period of time, as shown in FIG. 5B, a defect 35 is generated in the freezing outer tube 23, and leakage of a small amount of the coolant 31 is detected from the freezing outer tube 23. There is a case. When leakage of the cooling liquid 31 from the freezing outer pipe 23 is detected, the cooling liquid 31 is extracted from the freezing pipe 29 as shown in FIG. In addition, since the CB improvement muddy water 37 is filled between the outer peripheral surface 25 of the frozen outer pipe 23 and the inner peripheral surface 21 of the outer casing 3, a large amount of the coolant 31 leaks even if the defective portion 35 occurs. There is nothing.

次に、図５（ｃ）に示すように、凍結外管２３の上端の露出部を撤去し、凍結外管２３と凍結内管２４との間に追加凍結外管３９を設置して、新しい凍結管４９を形成する。そして、凍結外管２３の内周面４１と追加凍結外管３９の外周面４３との間に、熱伝導性を有する充填材である防錆材４５を充填する。さらに、凍結管４９内に充填した冷却液４７を、図示しない冷却液供給機構を用いて凍結内管２４から追加凍結外管３９へ循環させ、孔５の周囲の凍結土３３を維持する。   Next, as shown in FIG. 5 (c), the exposed portion at the upper end of the frozen outer tube 23 is removed, and an additional frozen outer tube 39 is installed between the frozen outer tube 23 and the frozen inner tube 24. A freezing tube 49 is formed. And between the inner peripheral surface 41 of the frozen outer tube 23 and the outer peripheral surface 43 of the additional frozen outer tube 39, a rust preventive material 45 which is a filler having thermal conductivity is filled. Further, the cooling liquid 47 filled in the freezing pipe 49 is circulated from the freezing inner pipe 24 to the additional freezing outer pipe 39 using a cooling liquid supply mechanism (not shown), and the frozen soil 33 around the hole 5 is maintained.

図５に示す工程は、地盤１に既に凍結土３３が構築された凍結維持段階であり、必要とする冷熱エネルギーが少ないため、凍結外管２３よりも径が細い追加凍結外管３９と交換しても特段の問題にはならない。   The process shown in FIG. 5 is a freezing maintenance stage in which the frozen soil 33 has already been constructed on the ground 1 and requires a small amount of cooling energy, so that it is replaced with an additional freezing outer pipe 39 having a smaller diameter than the freezing outer pipe 23. However, it is not a special problem.

このように、第２の実施の形態では、凍結管２９を設置するための削孔時に、孔５の壁面９と外ケーシング３の外周面１１との間および外ケーシング３の内部にＣＢ改良泥水３７を充填し、孔５の周囲の通水層６にＣＢ改良泥水３７を浸透させて改良層１５を形成する。これにより、凍結管２９の施工過程で、孔５の壁面９と外ケーシング３の外周面１１との間を閉塞し、通水層６の領域を効率良く改質することができ、凍結に支障となる水の流れを阻止することができる。   As described above, in the second embodiment, the CB improved muddy water is formed between the wall surface 9 of the hole 5 and the outer peripheral surface 11 of the outer casing 3 and inside the outer casing 3 when drilling for installing the freezing pipe 29. 37 is filled, and the CB improved mud water 37 is infiltrated into the water passing layer 6 around the hole 5 to form the improved layer 15. Thereby, in the construction process of the freezing pipe 29, the space between the wall surface 9 of the hole 5 and the outer peripheral surface 11 of the outer casing 3 can be closed, and the region of the water flow layer 6 can be efficiently reformed, which hinders freezing. Can be prevented from flowing.

また、凍結外管２３からの冷却液３１の漏出を検知した場合、凍結管２９から冷却液３１を抜き取り、凍結外管２３と凍結内管２４との間に追加凍結外管３９を設置して、新たな凍結管４９を形成する。これにより、凍結外管２３に欠損部３５が生じた時に迅速な補修が可能となる。   In addition, when leakage of the coolant 31 from the frozen outer tube 23 is detected, the coolant 31 is extracted from the frozen tube 29, and an additional frozen outer tube 39 is installed between the frozen outer tube 23 and the frozen inner tube 24. A new freezing tube 49 is formed. Thereby, when the defect | deletion part 35 arises in the frozen outer tube | pipe 23, quick repair becomes possible.

なお、第２の実施の形態では、孔５を掘削する際に流動性固化材としてＣＢ改良泥水３７を用いたが、流動性固化材の種類はこれに限らない。また、第１の実施の形態と同様に、通水層６の下方の地盤１の掘削に、流動性固化材の代わりに泥水を用いてもよい。さらに、外ケーシング３の内周面２１と凍結外管２３の外周面２５との間の充填材として防錆材２７を、凍結外管２３の内周面４１と追加凍結外管３９の外周面４３との間の充填材として防錆材４５を充填したが、これらの充填材は防錆剤に限らず、潤滑で熱伝導性を有するものであればよい。   In the second embodiment, the CB improved mud 37 is used as the fluidized solidifying material when the hole 5 is excavated, but the type of the fluidized solidified material is not limited thereto. Further, similarly to the first embodiment, mud water may be used instead of the fluidized solidifying material for excavation of the ground 1 below the water flow layer 6. Further, a rust preventive material 27 is used as a filler between the inner peripheral surface 21 of the outer casing 3 and the outer peripheral surface 25 of the frozen outer tube 23, and the outer peripheral surface of the inner peripheral surface 41 of the frozen outer tube 23 and the additional frozen outer tube 39. Although the rust preventive material 45 was filled as a filler between 43, these fillers are not restricted to a rust preventive agent, What is necessary is just what has heat conductivity by lubrication.

第１、第２の実施の形態では、隣り合う外ケーシング３の対向する位置に切欠きを設けてもよい。切欠きを設けることにより、隣りの外ケーシング３の方向へのＣＢ改良泥水の浸透が促進され、隣り合う孔５の間の通水層６をより効率良く改質することができる。   In 1st, 2nd embodiment, you may provide a notch in the position where the outer casing 3 which adjoins opposes. By providing the notches, the penetration of the CB improved mud water in the direction of the adjacent outer casing 3 is promoted, and the water-permeable layer 6 between the adjacent holes 5 can be more efficiently modified.

以上、添付図を参照しながら、本発明の実施形態を説明したが、本発明の技術的範囲は、前述した実施形態に左右されない。当業者であれば、特許請求の範囲に記載され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。   As mentioned above, although embodiment of this invention was described referring an accompanying drawing, the technical scope of this invention is not influenced by embodiment mentioned above. It will be obvious to those skilled in the art that various changes or modifications can be conceived within the scope of the technical idea described in the claims, and these are naturally within the technical scope of the present invention. It is understood that it belongs.

１………地盤
３………外ケーシング
５………孔
６………通水層
７………泥水
９………壁面
１１、２５、４３………外周面
１３、３７………ＣＢ改良泥水
１５………改良層
１９………止水部材
２１、４１………内周面
２３………凍結外管
２４………凍結内管
２７、４５………防錆材
２９、４９………凍結管
３１、４７………冷却液
３３………凍結土
５１………止水壁 1 ......... Ground 3 ......... Outer casing 5 ......... Hole 6 ......... Water-permeable layer 7 ......... Muddy water 9 ......... Wall surface 11, 25, 43 ......... Outer peripheral surface 13, 37 ......... CB Improved muddy water 15 ... Improved layer 19 ......... Water stop member 21, 41 ......... Inner peripheral surface 23 ...... Frozen outer tube 24 ......... Frozen inner tube 27, 45 ......... Rust prevention material 29, 49 ……… Freezing pipe 31, 47 ……… Coolant 33 ……… Frozen soil 51 ……… Stalling wall

Claims (6)

流動性固化材を外ケーシングの下方に所定の圧力で注入しつつ、前記外ケーシングを用いて地盤に孔を掘削し、前記孔の壁面と前記外ケーシングの外周面との間および前記外ケーシングの内部に前記流動性固化材を充填し、前記孔の周囲の通水層に前記流動性固化材を浸透させる工程ａと、
前記外ケーシング内に、凍結外管と凍結内管とからなる凍結管を挿入し、前記孔の周囲に凍結土を構築する工程ｂと、
を具備し、
前記工程ａでは、前記孔を前記通水層の下方まで掘削することを特徴とする凍結管の施工方法。 While injecting the fluidized solidified material below the outer casing at a predetermined pressure, a hole is excavated in the ground using the outer casing, and between the wall surface of the hole and the outer peripheral surface of the outer casing and between the outer casing and the outer casing. A step a in which the fluidized solidifying material is filled inside and the fluidized solidified material is permeated into a water-permeable layer around the hole;
In the outer casing, inserting a freezing tube composed of a frozen outer tube and a frozen inner tube, and constructing frozen soil around the hole; b
Equipped with,
In the step a, the method of constructing a freezing pipe is characterized in that the hole is excavated below the water-permeable layer . 流動性固化材を外ケーシングの下方に所定の圧力で注入しつつ、前記外ケーシングを用いて地盤に孔を掘削し、前記孔の壁面と前記外ケーシングの外周面との間および前記外ケーシングの内部に前記流動性固化材を充填し、前記孔の周囲の通水層に前記流動性固化材を浸透させる工程ａと、
前記外ケーシング内に、凍結外管と凍結内管とからなる凍結管を挿入し、前記孔の周囲に凍結土を構築する工程ｂと、
を具備し、
前記工程ｂで、前記凍結外管からの冷却液の漏出を検知した後、
前記凍結管から冷却液を抜き取り、前記凍結外管と前記凍結内管との間に追加凍結外管を設置する工程ｄをさらに具備することを特徴とする凍結管の施工方法。 While injecting the fluidized solidified material below the outer casing at a predetermined pressure, a hole is excavated in the ground using the outer casing, and between the wall surface of the hole and the outer peripheral surface of the outer casing and between the outer casing and the outer casing. A step a in which the fluidized solidifying material is filled therein and the fluidized solidified material is permeated into a water-permeable layer around the hole;
In the outer casing, inserting a freezing tube composed of a freezing outer tube and a freezing inner tube, and constructing frozen soil around the hole; b
Comprising
In step b, after detecting leakage of the coolant from the frozen outer tube,
The method for constructing a freezing pipe, further comprising a step d of extracting a cooling liquid from the freezing pipe and installing an additional freezing outer pipe between the freezing outer pipe and the freezing inner pipe. 流動性固化材を外ケーシングの下方に所定の圧力で注入しつつ、前記外ケーシングを用いて地盤に孔を掘削し、前記孔の壁面と前記外ケーシングの外周面との間および前記外ケーシングの内部に前記流動性固化材を充填し、前記孔の周囲の通水層に前記流動性固化材を浸透させる工程ａと、
前記外ケーシング内に、凍結外管と凍結内管とからなる凍結管を挿入し、前記孔の周囲に凍結土を構築する工程ｂと、
を具備し、
前記工程ａで、前記通水層の上方の地盤および／または前記通水層の下方の地盤では、前記流動性固化材の代わりに泥水を注入して前記孔を掘削することを特徴とする凍結管の施工方法。 While injecting the fluidized solidified material below the outer casing at a predetermined pressure, a hole is excavated in the ground using the outer casing, and between the wall surface of the hole and the outer peripheral surface of the outer casing and between the outer casing and the outer casing. A step a in which the fluidized solidifying material is filled inside and the fluidized solidified material is permeated into a water-permeable layer around the hole;
In the outer casing, inserting a freezing tube composed of a frozen outer tube and a frozen inner tube, and constructing frozen soil around the hole; b
Comprising
In the step a, in the ground above the water flow layer and / or the ground below the water flow layer, muddy water is injected instead of the fluidized solidified material to excavate the hole. Pipe construction method. 前記工程ａと前記工程ｂとの間に、前記外ケーシングの下端部付近を止水部材で閉塞し、前記外ケーシング内の前記流動性固化材を抜き取る工程ｃをさらに具備することを特徴とする請求項１記載の凍結管の施工方法。   Between the process a and the process b, the process further comprises a process c in which the vicinity of the lower end portion of the outer casing is closed with a water stop member and the fluidized solidified material in the outer casing is extracted. The construction method of the frozen pipe of Claim 1. 前記工程ｂで、前記外ケーシングの内周面と前記凍結外管の外周面との間に熱伝導性を有する充填材を充填することを特徴とする請求項４記載の凍結管の施工方法。 5. The method for constructing a freezing pipe according to claim 4 , wherein a filler having thermal conductivity is filled between the inner peripheral surface of the outer casing and the outer peripheral surface of the frozen outer pipe in the step b. 前記工程ｄで、前記凍結外管の内周面と前記追加凍結外管の外周面との間に熱伝導性を有する充填材を充填することを特徴とする請求項２記載の凍結管の施工方法。 The construction of the cryopipe according to claim 2 , wherein a filling material having thermal conductivity is filled between the inner peripheral surface of the frozen outer tube and the outer peripheral surface of the additional frozen outer tube in the step d. Method.
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CN109162722B (en) * 2018-10-11 2019-08-27 中国石油大学(华东) It is applicable in the advanced compacting grouting and reinforcing method in loose weak stratum of shallow-depth-excavation tunnel
JP7398740B2 (en) * 2020-04-20 2023-12-15 大成建設株式会社 Ground improvement method and ground improvement system
CN111945704A (en) * 2020-08-13 2020-11-17 中铁二十局集团第一工程有限公司 Method for reinforcing water-rich silt stratum by obliquely arranging multiple rows of freezing pipes

Family Cites Families (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS63223210A (en) * 1987-03-10 1988-09-16 Nippon Giken Kk Formation of water-impermeable layer
JP2683759B2 (en) * 1989-02-21 1997-12-03 清水建設株式会社 Micro clay suspension production equipment for underground injection
JP2739095B2 (en) * 1989-10-17 1998-04-08 建設省土木研究所長 Ground improvement method in tunnel excavation
JPH089222Y2 (en) * 1990-06-14 1996-03-13 株式会社フジクラ Ground freezing heat pipe
JP2002180456A (en) * 2000-12-11 2002-06-26 Kubota Corp Processing method for constructional sludge
US20070266715A1 (en) * 2006-05-16 2007-11-22 Sopko Joseph A Ground freezing method and apparatus with geothermal gradient compensation
JP4880406B2 (en) * 2006-09-13 2012-02-22 鹿島建設株式会社 Freezing material and ground freezing method
JP6341590B2 (en) * 2013-08-30 2018-06-13 ケミカルグラウト株式会社 Freezing method and freezing method construction system

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