JP3732427B2 - Improvement method of ground reinforcement in underground cavity - Google Patents

Description

【００２０】
この表１によれば、サンプル３が水中およびと酢酸浸漬条件での強度が良好であり、サンプル２が水中および酢酸浸漬条件での強度と流動性の双方の特性のバランスがよい。なお、本発明はこの例に限定されるものではなく、前記圧縮強度を満たし、かつ、ポンプ圧送と材料分離回避の面から、フロー値が７．０〜９ｃｍ程度の範囲の配合が好ましい。
いずれにしても実際の施工に際しては、テストサンプルによりフロー試験、及び圧縮強度試験を行い、必要な強度と流動性を有する配合を設定する。この配合に基づき必要量に応じた補修用材を製造する。
【００２１】
次に、本発明は、前記補強用材５を地中の空洞部ないし軟弱化部に圧入充填し、硬化させ強度を発現させる。
図２はその施工法の第１実施例を示している。この第１実施例はマンホール付近の下水道管Ａの漏水による欠陥地盤部１０（空洞部ないし軟弱化部位）に対する施工を示しており、前記のように調製した補修用材５を撹拌機能付きの貯蔵タンク６たとえばアジテーター車に収容し、圧送ポンプ７により導管８中を圧送し、マンホール１３の底付近から欠陥地盤部１０に向けたノズル９から圧入充填する。 前記導管８には補修用材５の流動性および充填部位までの距離に応じた注入圧を得るための圧力制御弁１１と欠陥地盤部１０の大きさに則した充填量に制御するための流量制御弁１２を設けている。さらに導管８には補修用材の圧入充填流量および注入圧が測定できるように流量圧力測定用計計器２２を設けている。
【００２２】
漏水部位は下水道管Ａの内外に通じているから、欠陥地盤部１０への補修用材５の充填に伴って下水道管Ａ内に補修用材５が浸入すると、それが下水道管内壁に固化して断面積を減少させ、以後の円滑な汚水の流れを阻害する可能性がある。また同時に、補修用材５が際限なく流出してしまう。
そこで、補修用材５の注入に先立ち、下水道管Ａ内に補修用材浸入防止手段１４を配して行なう。この補修用材浸入防止手段１４としては、ゴム袋などの可縮性膨張体が都合よく、収縮した状態で下水道管Ａ内に搬入し、補修用材５の欠陥地盤部１０への注入に先立って、可縮性膨張体内に流体供給源１５から空気あるいは水を注入して膨張させ、欠陥地盤部１０と通ずる漏水部の塞ぐように下水道管内壁に密着させる。この状態で補修用材５が硬化するまで保持させ、補修用材浸入防止手段１４を収縮して取り出せばよい。５’は充填された補修用材である。
【００２３】
図３ないし図６は施工法の第２実施例を示している。この第２実施例も下水道管Ａの漏水による欠陥地盤部１０（空洞部ないし軟弱化部位）に対する施工を示しているが、第１実施例と異なり、下水道管Ａの内部から欠陥地盤部１０に補修用材５を注入する点で異なっている。
【００２４】
この第２実施例においては、補修用材注入機を兼ねた補修用材浸入防止手段１４が用いられる。すなわち該手段は、軸方向中心に管体１６を有し、その外周に複数（この例では２つ）の可縮性膨張体１７，１７を相互に間隔をおいて設けている。前記管体１６は前後に下水道管Ａの内壁に接してスムースな移動を行なうためのガイド手段２０，２０を有している。ガイド手段２０，２０は駆動機構を有した自走式でもよい。
【００２５】
前記管体１６には左右の可縮性膨張体１７，１７間の管壁部位を貫いて補修用材５のノズル９が設けられており、ノズル９には導管８’が接続され、管体１６の軸方向に伸びている。導管８’の端部には圧送ポンプ７からの導管８が着脱可能に接続されるようになっている。また、可縮性膨張体１７，１７の中央部に対応する管体１６には膨張用流体の給排部１８，１８が設けられており、それら給排部１８，１８には管体１６の軸方向に伸びる導管１９が接続され、これに流体供給源１５からの導管が着脱可能に接続されるようになっている。
【００２６】
この第２実施例においては、図４のように、可縮性膨張体１７，１７を収縮させた状態にして補修用材浸入防止手段１４を下水道管Ａ内へと移動させ、可縮性膨張体１７，１７の間のノズル９が欠陥地盤部１０に略対峙する位置で停める。第１実施例、第２実施例のいずれも欠陥地盤部位１０に補修用材５を圧入するに先立って、欠陥地盤部１０の場所を任意の方法たとえばテレビカメラ、探傷器、圧気などによって検知し、あるいはさらに、欠陥地盤部位の規模や大きさを知るため、欠陥部位１０に給水してその給水量を予め測っておく。第２実施例においては、管体１６の先端にテレビカメラなどの検出手段を搭載しておくことができ、また、ノズル９から水を吐出させることにより欠陥地盤部位の規模や大きさを知ることができる。
【００２７】
ついで、図５のように導管１９から給排部１８，１８に流体を注入して可縮性膨張体１７，１７を膨張させ、欠陥地盤部位１０に近接する下水道管内壁に密着させる。これにより欠陥地盤部位１０に通ずる漏水個所１０’は可縮性膨張体１７，１７で囲繞された環状空間２１に存することになる。
そこで、補修用材５を圧送ポンプ７により導管８，８’に圧送し、ノズル９から吐出させる。これにより補修用材５は下水道管内の環状空間２１から漏水個所１０’を通して下水道管外の欠陥地盤部位１０に圧入充填される。
【００２８】
このようにして欠陥地盤部位１０が補修用材５で充填され、所要の時間が経過したならば、図６のように、可縮性膨張体１７，１７を収縮させ、導管８と導管８’との接続を外し、管体１６を移動させる。漏水個所１０’に対応する部分の下水道管内には補修用材５の一部が局部的に残存しているが、高圧水などを吹き付けることにより除去することができる。
【００２９】
この第２実施例の場合、補修用材浸入防止手段１４が移動自在であり、かつノズル９により下水道管内から漏水個所１０’を通して欠陥地盤部位１０に補修用材５を注入、充填するので、マンホール１３に近接した部位だけでなくかなり遠隔部位の施工にも適用できる利点がある。また、ノズル９から補修用材５を可縮性膨張体１７，１７で囲繞された環状空間２１に吐出させるので、漏水個所１０’が下水道管Ａの下部だけでなく側部および上部に存する場合にも、これにうまく充填することができる利点がある。
【００３０】
以上の方法により、地中の空洞部や軟弱部の地盤を強化し、しかもその地盤強度を補修等のために都合のよい大きさにすることができる。
なお、本発明において、骨材として活性汚泥式廃水処理過程から排出される剰余汚泥脱水ケーキの破砕物を使用することが必須であるが、必ずしも骨材使用量の全部でなくてもよく、強度や流動性を満足する限度で他の汎用の天然あるいは人工の骨材たとえば砂などを添加してもよい。
また、本発明は下水道で代表される地中埋設管周辺の漏水部位さらには空洞部の補強施工に好適であるが、そのほか、経年ビルの基礎の埋め戻し部分や、光ファイバーケーブル敷設管付近の施工にも適用しうる。
【００３１】
次に本発明の具体例を示す。
本発明による補修用材の強度と流動性を見るため、剰余汚泥脱水ケーキ破砕物の量を一定とし、固化材量および水量を種々にして補修用材を調製し、フロー試験と圧縮強度試験を行なった。これらは、水中養生、酢酸浸漬養生（酢酸濃度０．５％）で評価した。酢酸浸漬養生は有機酸に浸けられる環境における性能を知るためである。テストピースは前記表１と同じ条件とした。
なお、比較のため、剰余汚泥量を同じとし、固化材として普通セメントを使用した実験（添加量２４０ｋｇ／ｍ²）を行なったみたが、その結果は、７日強度で０．７ｋｇ／ｃｍ²であり、まったく強度不足であった。
【００３２】
【表２】

【００３３】
【表３】

【００３４】
これら表から、特に混和剤を添加していないにもかかわらず、サンプル▲１▼〜▲８▼は２８日強度において３ｋｇ／ｃｍ²を越えている。しかし、酢酸に浸された場合、サンプル▲１▼は２８日強度において３ｋｇ／ｃｍ²を下回っている。一方、サンプル▲７▼▲８▼は２８日強度は高いものの、流動性が低くなっている。したがって、強度と流動性の両面から、サンプル▲２▼〜▲６▼が好ましい補修用材である。特に、下水道管の空洞部類が置かれる有機酸環境２８日強度でも良好な強度が得られている。
【００３５】
次に、実際に地中の欠陥部位の地盤強化、改善効果を得られるかを試験した。この試験は、図７に示すように、透明樹脂パイプ２５を下水道管のモデルとして使用し、これを解体可能な箱体２６に設置し、透明樹脂パイプ２５の周囲に土２７を充填して圧密化した。一方、箱体２６の一側端部に注入口２８を設け、ここからノズル２９を挿込み、本発明の補修用材（表２におけるサンプル▲５▼を使用）を圧入した。
【００３６】
なお、箱体２６は幅４００ｍｍ、深さ４００ｍｍ、長さ１８００ｍｍとし、透明樹脂パイプ２５は外径２６５ｍｍ、長さ２０００ｍｍとし、ノズル２９は内径２０ｍｍのものを使用し、箱端から１５０ｍｍ突入させた。
前記樹脂パイプ２５の下部および側部に人工的に空洞部をつくり、その空洞部に、モルタルポンプを使用し、注入圧力を２．０ｋｇｆ／ｃｍ²にして補修用材を注入充填し、硬化させた。
【００３７】
この実験の結果、ノズルの閉塞は生じず、補修用材は空洞部を含む地中に浸透し、図８（ａ）（ｂ）のように透明樹脂パイプ２５の底部から上側部にかけて強化地盤部５’が形成されたことが確認された。なお、図８（ａ）は透明樹脂パイプ２５の前後を図７（ａ）に示すものと逆にして示している。
【００３８】
【発明の効果】
以上説明した本発明の請求項１，２によるときには、活性汚泥式廃水処理過程から排出される剰余汚泥脱水ケーキの破砕物を骨材とし、これに耐有機酸性のセメント系固化材を配合して、フロー値７〜９ｃｍ、硬化日数が２８日経た時点での圧縮強度が４〜７ｋｇｆ／ｃｍ^２程度、酢酸濃度０．５％の酢酸浸漬養生下での硬化日数が２８日経た時点での圧縮強度が３．４〜５．５ｋｇｆ／ｃｍ^２程度となるように構成した補修用材を用い、これを地中の空洞部ないし軟弱化部に圧入充填し、硬化させ、強度を発現させるので、下水道管で代表される地中構造物付近の軟弱化しあるいは空洞化したしかも有機酸環境下の欠陥部を、的確にしかも後の地中構造物の交換やメンテナンス作業に支障を来さないように強化、改善することができ、同時に処理に膨大な費用と手間をかけていた廃棄物を資源として再利用するため補修用材が安価なものとなり、施工費用を低コストにすることができるというすぐれた効果が得られる。
【００３９】
請求項３によれば、地中埋設管の内部への補修用材の浸入を防止できるため、補修用材の無駄な浪費を避けることができるとともに、補修用材の地中埋設管内での固化による下水の流れの悪影響を回避できるというすぐれた効果が得られる。 請求項４によれば、地中埋設管内からこれの欠陥個所を通して外部の軟弱化しあるいは空洞化した領域に補修用材を注入、充填することができるので、補修可能部位の範囲を広げることができ、また、ノズルから補修用材を可縮性膨張体で囲繞された環状空間に吐出させるので、漏水個所などの欠陥部分が地中埋設管の下部だけでなく全周部分に存する場合にも、これにうまく充填することができるというすぐれた効果が得られる。
【図面の簡単な説明】
【図１】本発明による地中空洞部の地盤強化改善法に使用する補修用材の配合を模式的に示す説明図である。
【図２】（ａ）は本発明による地中空洞部の地盤強化改善法の施工例を模式的に示す断面図、（ｂ）は（ａ）のＸ−Ｘ線に沿う断面図である。
【図３】本発明による地中空洞部の地盤強化改善法の他の施工例を模式的に示す断面図である。
【図４】（ａ）は図３の施工例の第１段階を示す断面図、（ｂ）は（ａ）のＹ−Ｙ線に沿う断面図である。
【図５】（ａ）は図３の施工例の第２段階を示す断面図、（ｂ）はその一部拡大図である。
【図６】図３の施工例の第３段階を示す断面図である。
【図７】（ａ）は本発明の実験装置の側面図、（ｂ）はその断面図である。
【図８】（ａ）は実験後の状態を示す側面図、（ｂ）はその断面図である。
【符号の説明】
１ 骨材（余剰汚泥破砕物）
２ セメント系固化材
５ 補修用材
１０ 欠陥地盤部位[0001]
BACKGROUND OF THE INVENTION
The present invention mainly relates to a method for improving ground reinforcement of underground cavities formed around pipes buried in the ground such as sewer pipes.
[0002]
[Prior art]
Various conduits (piping) are buried underground, but water leakage and intrusion from sewer pipes are social problems. In other words, joints such as fume pipes, ceramic pipes, and vinyl chloride pipes that are used as sewer pipes may be displaced near the pipe body by burying or by subsequent removal of mountain retaining materials, or by subsidence of the ground after burial. Cracks often occur, and sewage often leaks around the piping from such damaged or missing parts.
[0003]
As a result, the ground of the leaked water and the infiltration water is weakened, and further cavities are generated, and the sewage collected in the cavities forms a flow along the soft ground where the rolling pressure is insufficient and is left as it is. Then it grows into a groundwater vein. The groundwater veins formed by this sewage induce problems such as depression due to land subsidence and precious groundwater contamination.
However, in the past, the repair method has often been left because there is no practical method that satisfies the economics, and the problem of environmental damage due to leakage from the sewer pipes and intrusion water has been getting worse.
[0004]
[Problems to be solved by the invention]
The present invention has been made in order to solve the above-mentioned problems, and the object of the present invention is an underground defect portion softened or hollowed out due to water leakage or intrusion from underground pipes such as sewer pipes. Can be strengthened and improved so as not to hinder the replacement and maintenance work of underground pipes in the future, and it is possible to do so at low cost. It is to provide.
[0005]
In addition to the above object, another object of the present invention is to provide a ground reinforcement improving method for underground cavities that can be carried out while preventing the material for improving ground reinforcement from adhering to the underground pipe. is there.
[0006]
[Means for Solving the Problems]
In order to achieve the first object, in the present invention, in order to reinforce and improve the hollow portion or softened portion generated in the ground, the surplus sludge dewatered cake crushed material discharged from the activated sludge wastewater treatment process is boned. This material is mixed with an organic acid-resistant cement-based solidified material, and has a flow value of 7 to 9 cm, a compressive strength of about 4 to 7 kgf / cm ² after 28 days of curing, and an acetic acid concentration of 0.5%. Using a repair material constructed so that the compressive strength is about 3.4 to 5.5 kgf / cm ² when the number of days of curing under acetic acid immersion curing is 28 days, It is characterized in that it is press-filled into the forming part, cured, and developed in strength.
The hollow portion or softened portion generated in the ground is typically a hollow portion or softened portion due to water leakage or intrusion water around the underground pipe.
[0007]
In order to achieve the second object, the present invention is carried out by providing means for preventing the entry of a repair material in the underground pipe in the portion corresponding to the cavity or weakened portion caused by water leakage or intrusion water. Preferably, when the repair material is used and is press-fitted into a hollow portion or softened portion in the ground, a pipe body is provided at the center in the axial direction as a means for preventing the intrusion of the repair material, and a plurality of outer peripheral members are provided on the outer periphery thereof. A retractable expansion body is provided with a space between each other, and a nozzle in which a repair material is injected into a tube wall portion between the expandable expansion bodies is used. The invasion prevention means of the repair material is arranged in the underground pipe so that it is located in the part corresponding to the softened part, the contractible expansion body is expanded, and the repair material from the nozzle is externally passed through the defective part of the underground pipe. To discharge.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described below with reference to the accompanying drawings.
First, the ground reinforcement improvement method of the underground cavity of the present invention uses a special composition as the repair material 5. Basically, as shown in Fig. 1, the surplus sludge dewatered cake crushed material 1 discharged from the activated sludge wastewater treatment process is used as an aggregate, and this is mixed with cement-based solidified material 2 and water 3 and mixed uniformly. For example, it comprises a milky composition having a density of 1.0 to 2.5 g / cm ² and a pH of 13 to 14. Admixture 4 or the like may be further added to the composition.
[0009]
If it explains in full detail, the characteristic of the repair material 5 by this invention exists in using the surplus sludge dewatering cake discharged | emitted from an activated sludge type wastewater treatment facility as an aggregate. Conventionally, most of these sludge dewatered cakes are incinerated, but due to their high water content, they are difficult to burn and must use fuels such as heavy oil, which consumes a lot of fuel and energy loss. is there. In addition, it was difficult to deal with smoke and residual ash generated due to incineration. The present invention recycles surplus sludge from such industrial waste as a raw material for repairing / strengthening / improving the softened ground state before the formation of underground cavities or cavities, and at the same time, reducing the cost of repairing materials. It is a plan to make it.
[0010]
In the present invention, surplus sludge dewatered cake crushed material 1 is obtained by stirring and grinding a dewatered cake. The dewatered cake of surplus sludge from public sewers has an organic matter content (average) of about 64% in the summer and about 70% in the winter, and a moisture content of about 70 to 82%. The dehydrated cake in this state is charged into a hopper, a tank or the like, and mechanically divided and crushed by stirring means such as a mixer.
The surplus sludge dewatered cake crushed material 1 is a rounded granular material having a maximum particle size of about 1.5 mmφ or less in a surface-dried state. And since the said particle size is comparatively equal, the fluidity | liquidity at the time of making a repair material and pumping this and injecting and filling to an object part will become good. For this reason, the present invention uses the surplus sludge crushed material 1 as an aggregate.
[0011]
Further, the dehydrated cake and the granular material treated with this are usually 45 to 59% carbon, 5 to 8% hydrogen, 5 to 10% nitrogen, 0.5 to 2.1% flammable sulfur, oxygen It is 23 to 37%, and the fiber content such as cellulose is considerably contained in this composition. Since this fiber component functions as a binder, it is possible to improve the inseparability in water. For this reason as well, the present invention uses the surplus sludge crushed material 1 as an aggregate.
[0012]
Next, as the cement-based solidifying material 2, ordinary cement typified by general-purpose Portland cement is inappropriate. The reason is that a lot of organic matter is contained in the domestic wastewater that passes through the sewer pipe, and when it is spoiled, it becomes an organic acid. When such domestic wastewater leaks from the sewer pipe, the cavity and the weakened part are in an organic acid environment. This is because the organic acid inhibits the hydration reaction of the cement and delays the solidification action, so that ordinary cement cannot function as the repair material intended in the present invention.
[0013]
Therefore, the present invention uses a cement-based solidifying material 2 having organic acid resistance. A suitable example of the cement-based solidifying material 2 has a composition in which an organic acid-resistant substance is added to cement. As a specific example, a trade name Zeoset GS30 related to the manufacture of Taiheiyo Cement Co., Ltd. can be mentioned. This cement-based solidified material is in powder form, has a density of about 2.99 g / cm ³ and a specific surface area of 4850 cm ² / g, and contains chemical components such as silicon dioxide, aluminum oxide, ferric oxide, calcium oxide, magnesium oxide. Contains sulfur disulfide.
[0014]
In the present invention, the residual sludge crushed material 1, the cement-based solidified material 2, and at least water 3 have a compressive strength (strength under water curing in accordance with Japanese Industrial Standards) at the time when the curing days in the range of 28 days have passed. 3 to 15 kgf / cm ² , more preferably 4 to 10 kgf / cm ² , and most preferably 4 to 7 kgf / cm ² , measured at a predetermined weight ratio, and mixed uniformly with a mixer or the like. A repairing material 5 with good properties is obtained.
[0015]
The strength range is limited because it is better to have high compressive strength in order to strengthen the ground of the cavity and softened part, but unlike ordinary underground structures, sewer pipes are used for route changes, etc. It may be re-excavated and removed from the ground or repaired. At that time, if the compressive strength is too high, it becomes difficult to destroy the ground containing the repair material that has been solidified with a scoop or a simple destructive device, which requires a lot of work and time. For this reason, it is necessary to have an appropriate strength that is neither too soft nor too hard. If the compressive strength at the time when the curing days in the range of 28 days elapses is within the above range, the strength is practically sufficient and the operation can be easily performed.
[0016]
Furthermore, if the strength of the ground containing the hardened repair material is too high, the ground containing the hardened repair material functions as a fulcrum, and promotes the progress of cracks and cracks in the sewer pipe, but if the strength range Even when the sewer pipe sinks unevenly, it can follow this well. From this point as well, the strength range is limited.
[0017]
Furthermore, in order to obtain the strength and fluidity within the above-mentioned range, it is also convenient to add one or more desired admixtures such as a swelling agent, an AE water reducing agent, a fluidizing agent, and a non-separating agent in water. What is necessary is just to set those addition amount suitably, for example, with respect to the cement-type solidification material 2, about 5 to 8% of a swelling agent, about 0.6 to 1% of a fluidizing agent, about 2% of AE water reducing agents, About 1.0% of the non-separating agent in water may be added.
[0018]
Table 1 shows the contents and results of an experiment in which the amount of surplus sludge dewatered cake crushed material 1 is kept constant in order to determine the blending ratio of the repair material 5. The surplus sludge dehydrated cake crushed material 1 was used having a maximum particle size of 1.5 mm or less (surface dried state).
As the cement-based solidifying material in the table, trade name ZEOSET GS30 related to the manufacture of Taiheiyo Cement Co., Ltd. was used.
The fluidity was evaluated by a flow test. After filling a cylindrical container having a diameter of about 3.0 cm and a height of about 4.5 cm with a repair material and opening the bottom surface of the cylindrical container, it was dropped on the floor surface, The average value of the values orthogonal to the diameter of the sample spread on the floor surface was judged as good or bad with a fluidity of about 8 cm. ○ indicates good, and ◎ indicates extremely good. The compressive strength was set to two types: water curing and acetic acid immersion conditions. The latter corresponds to the environment in contact with organic acids.
[0019]
[Table 1]

[0020]
According to Table 1, the strength of sample 3 in water and in acetic acid immersion conditions is good, and sample 2 has a good balance of both strength and fluidity characteristics in water and acetic acid immersion conditions. In addition, this invention is not limited to this example, The mixing | blending of the range whose flow value is about 7.0-9 cm is preferable from the surface of satisfying the said compressive strength and avoiding pumping and material separation.
In any case, in actual construction, a flow test and a compressive strength test are performed using a test sample, and a blend having necessary strength and fluidity is set. Based on this formulation, a repair material corresponding to the required amount is manufactured.
[0021]
Next, in the present invention, the reinforcing material 5 is press-filled into a hollow portion or a softened portion in the ground, and cured to develop strength.
FIG. 2 shows a first embodiment of the construction method. This first embodiment shows a construction for a defective ground part 10 (cavity part or softened part) due to water leakage in a sewer pipe A near a manhole, and a storage tank with a stirring function for the repair material 5 prepared as described above. 6 For example, it is accommodated in an agitator vehicle, and is pumped through the conduit 8 by the pump 7 and is press-fitted from the nozzle 9 toward the defective ground portion 10 from near the bottom of the manhole 13. The conduit 8 has a flow rate control for controlling the filling amount according to the size of the pressure control valve 11 and the defective ground portion 10 for obtaining the injection pressure corresponding to the fluidity of the repair material 5 and the distance to the filling site. A valve 12 is provided. The conduit 8 is further provided with a flow rate pressure measuring instrument 22 so that the press-fitting flow rate and injection pressure of the repair material can be measured.
[0022]
Since the water leakage site is connected to the inside and outside of the sewer pipe A, when the repair material 5 enters the sewer pipe A with the filling of the repair material 5 to the defective ground portion 10, it solidifies on the inner wall of the sewer pipe and breaks. It may reduce the area and hinder subsequent smooth sewage flow. At the same time, the repair material 5 flows out without limit.
Therefore, prior to the injection of the repair material 5, the repair material intrusion prevention means 14 is disposed in the sewer pipe A. As the repair material intrusion prevention means 14, a retractable inflatable body such as a rubber bag is conveniently carried into the sewer pipe A in a contracted state, and prior to injection of the repair material 5 into the defective ground portion 10, Air or water is injected from the fluid supply source 15 into the expandable expandable body and expanded, and is brought into close contact with the inner wall of the sewer pipe so as to close the leaked portion communicating with the defective ground portion 10. In this state, the repair material 5 is held until it is cured, and the repair material intrusion prevention means 14 is contracted and taken out. 5 ′ is a filled repair material.
[0023]
3 to 6 show a second embodiment of the construction method. Although this 2nd Example also has shown the construction with respect to the defective ground part 10 (cavity part or weakened part) by the water leak of the sewer pipe A, unlike the 1st Example, from the inside of the sewer pipe A to the defective ground part 10 The difference is that the repair material 5 is injected.
[0024]
In the second embodiment, the repair material intrusion preventing means 14 which also serves as a repair material injection machine is used. That is, the means has a tubular body 16 at the center in the axial direction, and a plurality of (in this example, two) contractible expansion bodies 17 and 17 are provided on the outer periphery thereof at intervals. The pipe body 16 has guide means 20 and 20 for smoothly moving in contact with the inner wall of the sewer pipe A in the front-rear direction. The guide means 20, 20 may be a self-propelled type having a drive mechanism.
[0025]
The pipe body 16 is provided with a nozzle 9 for the repair material 5 penetrating through the pipe wall portion between the left and right retractable expansion bodies 17, 17, and a conduit 8 ′ is connected to the nozzle 9. It extends in the axial direction. A conduit 8 from the pressure pump 7 is detachably connected to the end of the conduit 8 '. Further, the pipe body 16 corresponding to the center part of the contractible expansion bodies 17 and 17 is provided with supply and discharge portions 18 and 18 for the expansion fluid, and the supply and discharge portions 18 and 18 include the pipe body 16. An axially extending conduit 19 is connected to which a conduit from the fluid supply 15 is detachably connected.
[0026]
In the second embodiment, as shown in FIG. 4, the contractible expandable bodies 17, 17 are contracted, and the repair material intrusion preventing means 14 is moved into the sewer pipe A, so that the contractible expandable body. The nozzle 9 between 17 and 17 stops at a position substantially facing the defective ground portion 10. Prior to press-fitting the repair material 5 into the defective ground portion 10 in both the first embodiment and the second embodiment, the location of the defective ground portion 10 is detected by an arbitrary method such as a TV camera, a flaw detector, and pressure air. Or, furthermore, in order to know the scale and size of the defective ground part, water is supplied to the defective part 10 and the amount of water supply is measured in advance. In the second embodiment, detection means such as a television camera can be mounted on the tip of the tube body 16, and the size and size of the defective ground portion can be known by discharging water from the nozzle 9. Can do.
[0027]
Next, as shown in FIG. 5, fluid is injected from the conduit 19 to the supply / discharge portions 18, 18 to expand the contractible expansion bodies 17, 17, and are brought into close contact with the inner wall of the sewer pipe adjacent to the defective ground portion 10. As a result, the water leaking portion 10 ′ leading to the defective ground portion 10 exists in the annular space 21 surrounded by the contractible expansion bodies 17 and 17.
Therefore, the repairing material 5 is pumped to the conduits 8 and 8 ′ by the pumping pump 7 and discharged from the nozzle 9. As a result, the repair material 5 is press-fitted and filled into the defective ground portion 10 outside the sewer pipe from the annular space 21 in the sewer pipe through the water leakage location 10 '.
[0028]
In this way, when the defective ground portion 10 is filled with the repair material 5 and the required time has elapsed, the contractible expandable bodies 17 and 17 are contracted as shown in FIG. Is disconnected, and the tube body 16 is moved. Although a part of the repair material 5 remains locally in the sewer pipe corresponding to the water leak location 10 ', it can be removed by spraying high pressure water or the like.
[0029]
In the case of this second embodiment, the repairing material intrusion preventing means 14 is movable, and the repairing material 5 is injected and filled into the defective ground part 10 through the leaked part 10 ′ from the sewer pipe by the nozzle 9. There is an advantage that it can be applied not only to a close part but also to a considerably remote part. In addition, since the repair material 5 is discharged from the nozzle 9 to the annular space 21 surrounded by the retractable expansion bodies 17 and 17, when the water leakage place 10 ′ exists not only in the lower part of the sewer pipe A but also in the side part and the upper part. Also has the advantage that it can be filled well.
[0030]
By the above method, it is possible to reinforce the ground of the hollow portion and the soft portion in the ground, and to make the strength of the ground convenient for repair or the like.
In the present invention, it is indispensable to use the crushed waste sludge dewatered cake discharged from the activated sludge wastewater treatment process as an aggregate, but it is not necessarily the total amount of aggregate used, and the strength In addition, other general-purpose natural or artificial aggregates such as sand may be added as long as the fluidity is satisfied.
In addition, the present invention is suitable for the reinforcement work of the leaked part around the underground buried pipe represented by the sewerage system and the cavity part, but in addition, the backfill part of the foundation of an aged building and the construction near the optical fiber cable laying pipe It can also be applied to.
[0031]
Next, specific examples of the present invention will be shown.
In order to see the strength and fluidity of the repair material according to the present invention, the amount of surplus sludge dewatered cake crushed material was kept constant, the repair material was prepared with various amounts of solidified material and water, and the flow test and the compressive strength test were performed. . These were evaluated by water curing and acetic acid immersion curing (acetic acid concentration 0.5%). Acetic acid immersion curing is for knowing the performance in an environment immersed in an organic acid. The test piece had the same conditions as in Table 1 above.
For comparison, an experiment using the same amount of excess sludge and using ordinary cement as a solidifying material (addition amount 240 kg / m ² ) was conducted, and the result was 0.7 kg / cm ² at 7 days strength. The strength was insufficient.
[0032]
[Table 2]

[0033]
[Table 3]

[0034]
From these tables, samples (1) to (8) exceeded 3 kg / cm ² at 28 days strength, although no admixture was added. However, when immersed in acetic acid, sample (1) is below 3 kg / cm ² at 28 days strength. On the other hand, Samples (7) and (8) have a high fluidity on the 28th, but have low fluidity. Therefore, samples (2) to (6) are preferable repair materials in terms of both strength and fluidity. In particular, good strength is obtained even in the organic acid environment 28-day strength where the cavities of the sewer pipe are placed.
[0035]
Next, it was tested whether the ground strengthening and improvement effect of the defect site in the ground could be actually obtained. In this test, as shown in FIG. 7, a transparent resin pipe 25 is used as a model of a sewer pipe, this is installed in a box 26 that can be dismantled, and soil 27 is filled around the transparent resin pipe 25 for consolidation. Turned into. On the other hand, an injection port 28 was provided at one end of the box body 26, and a nozzle 29 was inserted therefrom, and the repair material of the present invention (sample (5) in Table 2) was press-fitted.
[0036]
The box 26 has a width of 400 mm, a depth of 400 mm, and a length of 1800 mm, the transparent resin pipe 25 has an outer diameter of 265 mm and a length of 2000 mm, and a nozzle 29 having an inner diameter of 20 mm is used and is made to enter 150 mm from the end of the box. .
Cavity portions were artificially formed in the lower and side portions of the resin pipe 25, and a mortar pump was used in the cavity portion to inject and fill a repair material with an injection pressure of 2.0 kgf / cm ² and cured. .
[0037]
As a result of this experiment, nozzle clogging does not occur, and the repair material penetrates into the ground including the cavity, and the reinforced ground portion 5 extends from the bottom to the upper side of the transparent resin pipe 25 as shown in FIGS. It was confirmed that 'was formed. FIG. 8A shows the front and rear of the transparent resin pipe 25 reversed from that shown in FIG.
[0038]
【The invention's effect】
According to claims 1 and 2 of the present invention described above, the crushed material of the residual sludge dewatered cake discharged from the activated sludge wastewater treatment process is used as an aggregate, and an organic acid-resistant cement-based solidifying material is blended into this. Compressive strength after 28 days of curing under acetic acid immersion curing with a flow value of 7-9 cm, a compressive strength of about 4-7 kgf / cm ² when the curing days are 28 days, and an acetic acid concentration of 0.5% Since the repair material configured to have a strength of about 3.4 to 5.5 kgf / cm ² is press-filled into a hollow portion or a softened portion in the ground and cured to develop strength, sewerage Reinforced so as not to hinder the replacement and maintenance work of the underground structure, which has been softened or hollowed out in the vicinity of the underground structure represented by the pipe, and that is defective in the organic acid environment. Can be improved, the same Enormous costs and repair timber for recycling waste have effort as a resource to process becomes inexpensive, excellent effect that it is possible to the construction costs at low cost is obtained.
[0039]
According to claim 3, since it is possible to prevent the repair material from entering the underground buried pipe, wasteful use of the repair material can be avoided, and sewage caused by solidification of the repair material in the underground buried pipe can be avoided. An excellent effect is obtained that the adverse effects of the flow can be avoided. According to claim 4, since it is possible to inject and fill the repair material into the externally weakened or hollowed area through the defective portion from the underground pipe, the range of repairable parts can be expanded, In addition, since the repair material is discharged from the nozzle into the annular space surrounded by the retractable expansion body, even if there are defective parts such as water leakage not only in the lower part of the underground pipe, but also in the entire circumference part. The excellent effect that it can be filled well is obtained.
[Brief description of the drawings]
BRIEF DESCRIPTION OF DRAWINGS FIG. 1 is an explanatory view schematically showing the composition of a repair material used in a ground reinforcement improvement method for underground cavities according to the present invention.
FIG. 2A is a cross-sectional view schematically showing a construction example of a method for improving ground reinforcement of an underground cavity according to the present invention, and FIG.
FIG. 3 is a cross-sectional view schematically showing another construction example of the method for improving ground reinforcement of underground cavities according to the present invention.
4A is a cross-sectional view showing a first stage of the construction example of FIG. 3, and FIG. 4B is a cross-sectional view taken along line YY of FIG.
5A is a cross-sectional view showing a second stage of the construction example of FIG. 3, and FIG. 5B is a partially enlarged view thereof.
6 is a cross-sectional view showing a third stage of the construction example in FIG. 3;
7A is a side view of the experimental apparatus of the present invention, and FIG. 7B is a cross-sectional view thereof.
8A is a side view showing a state after the experiment, and FIG. 8B is a cross-sectional view thereof.
[Explanation of symbols]
1 Aggregate (excess sludge crushed material)
2 Cement-based solidified material 5 Repair material 10 Defective ground part

Claims (4)

In strengthening and improving the cavity or softening part generated in the ground, the surplus sludge dewatered cake crushed material discharged from the activated sludge wastewater treatment process is used as an aggregate, and this is an organic acid-resistant cementitious solidified material. , The flow value was 7-9 cm, the compression strength at the time when the curing days were 28 days, about 4-7 kgf / cm ² , and the curing days were 28 days under acetic acid immersion curing with acetic acid concentration 0.5% Using a repair material configured so that the compressive strength at the time becomes about 3.4 to 5.5 kgf / cm ² , this is press-filled into a hollow portion or softened portion in the ground, and cured to develop strength. A method for improving ground reinforcement in an underground cavity, characterized by comprising: 2. The method for improving ground reinforcement of an underground cavity according to claim 1, wherein the cavity or the weakened part generated in the ground is a cavity or a weakened part around the underground pipe. The method for improving ground reinforcement of an underground cavity according to claim 2, which is carried out by providing means for preventing entry of a repair material into the underground pipe. When using the repair material according to claim 1 and press-fitting it into a hollow portion or softening portion in the ground, a pipe body is provided at the center in the axial direction as a means for preventing intrusion of the repair material. The contractible expansion body is provided with a space between each other, and a nozzle for injecting a repair material into the tube wall portion between the contractible expansion bodies is used. Or, the intrusion prevention means of the repair material is arranged in the underground pipe so as to be located at the site corresponding to the softened portion, the contractible expansion body is expanded, and the repair material from the nozzle is passed through the defective portion of the underground pipe. The ground reinforcement | strengthening improvement method of the underground hollow part of Claim 1 discharged to the exterior.

Images