JP2004231884A

JP2004231884A - Injection material

Info

Publication number: JP2004231884A
Application number: JP2003024605A
Authority: JP
Inventors: Makoto Asami; 誠朝見; Fumio Akisato; 文雄秋里; Hidenori Isoda; 英典礒田; Ryozo Yoshida; 了三吉田; Shunichiro Uchida; 俊一郎宇智田
Original assignee: Taiheiyo Materials Corp
Current assignee: Taiheiyo Materials Corp
Priority date: 2003-01-31
Filing date: 2003-01-31
Publication date: 2004-08-19

Abstract

<P>PROBLEM TO BE SOLVED: To provide an injection material which shows very high permeability when it is injected even into a ground etc., of a low coefficient of permeability and does not bring out a decrease in a strength development at an early to middle period after injection. <P>SOLUTION: The injection material comprises slag(A) of 50-90 pts.wt., gypsum(B) of 0.5-3 pts.wt. in terms of SO<SB>3</SB>, a cement clinker(C) of 10-50 pts.wt., a naphthalene sulfonic acid-based water reducing agent(D) or a mixture of a naphthalene sulfonic acid-based water reducing agent and a melamine sulfonic acid-based one of 0.1-5 pts.wt. and at least one sort(E) of 0.1-5 pts.wt. selected from a soluble sulfate, soluble thiosulfate and soluble sulfite except gypsum, and at least 95 vol% of the particles contained in the injection material except the particle of (E) is a particle having a particle diameter of not more than 10.5 μm and the particle having a diameter of not more than 2.2 μm is not more than 45 vol%. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

【０００１】
【発明の属する技術分野】
本発明は、軟弱地盤や脆弱な岩盤等を硬強・堅牢なものに改良したり、建設物の基礎強化や止水などに用いる注入材に関する。
【０００２】
【従来の技術】
地盤や岩盤をより硬強・堅牢なものにしたり、液状化を防ぐために、水硬性物質を主成分とする注入材が地盤の土壌粒子間隙や岩盤の亀裂などに水性スラリー化した上で注入使用されている。注入対象が透水係数の小さい地盤等に対しては注入材の浸透性を特に高める必要があり、このような注入材として、最大粒径をかなり小さくしたセメントクリンカと比表面積の高い高炉スラグを有効成分とする所謂超微粒子系の注入材が知られている。（例えば、特許文献１参照）。しかしながら、超微粒子系の注入材は粒径約２μｍ以下の微粒子が大量に含まれるため、スラリー中で微粒子が凝集化し易く、注入時の浸透性が低下したり、地盤中で、注入材有効成分の濃度ムラが生じ易い。このため注入材構成粒子の粒径を特定の範囲に調整し、スラリー注入時の浸透性を改善することが行なわれている。（例えば、特許文献２参照）。また、セメント用の減水剤の類を配合使用すれば、分散性を高めて粒子の凝集化を抑制することができるが、少なくともスラリー作製時点から注入実施までの間、凝集化を十分抑制し続けるには減水剤を概して大量に要し、スラリー作製時から注入するまでの時間をより長くするには、減水剤類の配合量を一層増加させる必要がある。一方で高価な減水剤の配合量を増すと、材料コストの上昇に加え、初期〜中長期の強度発現性が低下し易くなる等の問題が生じる。
【０００３】
【特許文献１】
特許第２８９４５２９号公報
【特許文献２】
特開平９−２５５３７８号公報
【０００４】
【発明が解決しようとする課題】
本発明は、浸透係数の低い地盤等へ注入しても極めて高い浸透性を示し、注入後も初期〜中期の強度発現性の低下をもたらすことのない注入材を提供することを課題とする。
【０００５】
【課題を解決するための手段】
本発明者らは前記課題解決のため検討を重ねた結果、スラグ−セメント系組成物の粒径を規定し、これに特定の減水剤を配合した水性スラリーが浸透係数の低い地盤等へ注入しても極めて高い浸透性を示し、しかもこの浸透性をスラリー作製時から比較的長時間安定して保つことができ、更に石膏を除く可溶性硫酸塩、可溶性チオ硫酸塩、可溶性亜硫酸塩の何れか１種以上を配合することによって高い浸透性を維持したまま初期〜中期の強度発現性低下を十分防ぐことができたことから本発明を完成するに至った。
【０００６】
即ち本発明は、（Ａ）スラグ５０〜９０重量部、（Ｂ）石膏をＳＯ_３換算で０．５〜３重量部、（Ｃ）セメントクリンカ１０〜５０重量部、（Ｄ）ナフタレンスルホン酸系減水剤又はナフタレンスルホン酸系減水剤とメラミンスルホン酸系減水剤０．１〜５重量部及び（Ｅ）石膏を除く可溶性硫酸塩、可溶性チオ硫酸塩、可溶性亜硫酸塩の何れか１種以上０．１〜５重量部、を含有してなる注入材であって、（Ｅ）の粒子を除く注入材中の粒子の９５体積％以上が粒径１０．５μｍ以下の粒子であり、粒径２．２μｍ以下の粒子が４５体積％以下であることを特徴とする注入材である。
【０００７】
【発明の実施の形態】
本発明の注入材に含有されるスラグは、粉末状のものとする他は、特に限定されず、例えば高炉スラグ、下水汚泥溶融スラグ、都市ゴミ溶融スラグ等を挙げることができる。望ましくは高ガラス化率のスラグが良く、例えば急冷した高炉水砕スラグなどが適当である。本注入材中のスラグ含有量は、５０〜９０重量部とする。５０重量部未満では浸透性が低下するので好ましくなく、また９０重量部を超えると凝結固化能力が低下するので好ましくない。
【０００８】
本発明の注入材に含有される石膏は、粉末状のものとする他は、無水石膏、半水石膏、二水石膏の何れか１種または２種以上であっても良く、また更には公知の化学石膏と称されているものでも良い。石膏は、専らエトリンガイト生成による初期強度発現性増進作用を付与し、また硬化促進作用にも寄与するため含有される。本注入材中の石膏含有量は、例えばポルトランドセメント等が配合含有される場合は該セメント中に含まれている石膏成分も含めた総含有量とし、ＳＯ_３換算で０．５〜３重量部とする。石膏含有量がＳＯ_３換算で０．５重量部未満では初期強度発現性が低迷するので好ましくなく、また３重量部を超えると浸透性が低下するので好ましくない。
【０００９】
本発明の注入材に含有されるセメントクリンカは、石灰石などのセメント原料を例えば１３００〜１４５０℃で焼成して得られるものであって、水和反応性物質を主要生成相とするものであれば特に限定されない。該セメントクリンカの本注入材への含有形態としては、粉末状のものとする以外は、セメントクリンカ粉末単体であっても、このようなセメントクリンカを用いたセメント粉末として含有したものあっても良い。後者の場合、セメントの種類は限定されない。本注入材中のセメントクリンカ含有量は、１０〜５０重量部とする。この含有量は、セメント粉末として含有させた場合は、セメント中に含まれるクリンカ相当成分が注入材に占める量とし、またセメントクリンカ粉末単体も共に含有させる時は該単体量と合わせた量とする。セメントクリンカ含有量が１０重量部未満では凝結が遅延し過ぎるため好ましくなく、５０重量部を超えると浸透性が著しく低下するので好ましくない。
【００１０】
本発明の注入材は減水剤を含有するが、減水剤としては、ナフタレンスルホン酸系減水剤を必須使用する。好ましくは、ナフタレンスルホン酸系減水剤とメラミンスルホン酸系減水剤とを併用したものとする。かかる減水剤は、高性能減水剤や高性能ＡＥ減水剤或いは分散剤と称されるものであっても良い。ナフタレンスルホン酸系減水剤を含有することにより少ない使用量でも注入材の浸透性を著しく高めることができ、また初期〜中期の強度発現性に殆ど影響を及ぼすことなくスラリー中の粒子凝集抑制時間を伸長させることが可能である。更に、ナフタレンスルホン酸系減水剤に加えてメラミンスルホン酸系減水剤を併用することにより特にスラリー中の粒子凝集抑制時間を大幅に伸長させることが可能である。
【００１１】
含有可能なナフタレンスルホン酸系減水剤は特に制限されず、例えばナフタレンスルホン酸ホルマリン高縮合物塩を有効成分とするもの、ナフタレンスルホン酸ソーダのホルマリン縮合物を有効成分とするもの、ナフタレンスルホン酸ナトリウム塩ホルマリン重縮合物を有効成分とするもの、高縮合芳香族スルホン酸を有効成分とするもの、変性リグニンと高縮合芳香族スルホン酸複合体を有効成分とするもの、アルキルアリルスルホン酸を有効成分とするもの、アルキルアリルスルホン酸塩を有効成分とするもの、アルキルアリルスルホン酸高縮合物を有効成分とするもの、アルキルアリルスルホン酸塩高縮合物を有効成分とするもの、アルキルナフタレンスルホン酸ホルマリン縮合物を有効成分とするもの、ナフタレンスルホン酸変性リグニン縮合物を有効成分とするもの、ナフタレンスルホン酸変性リグニン縮合物とリグニンを有効成分とするもの、変性リグニンとアルキルアリルスルホン酸と活性持続ポリマーの複合物を有効成分とするもの、ポリアルキルスルホン酸と反応性高分子を有効成分とするもの、アルキルアリルスルホン酸高縮合物とカルボキシル基含有多価ポリマーを有効成分とするもの、アルキルアリルスルホン酸塩変性リグニン共縮合物と変性リグニンを有効成分とするもの、リグニン誘導体とアルキルアリルスルホン酸塩を有効成分とするもの、ポリアルキルアリルスルホン系界面活性剤を有効成分とするもの、アルキルアリルスルホン酸ホルマリン縮合物を有効成分とするもの、ポリアルキルアリルスルホン酸化合物を有効成分とするもの等を挙げることができる。
【００１２】
また、含有可能なメラミンスルホン酸系減水剤も特に制限されず、例えばメラミンスルホン酸系縮合物を有効成分とするもの、メラミンスルホン酸系化合物を有効成分とするもの、メラミンスルホン酸系化合物とポリオール複合体を有効成分とするもの、高縮合トリアジン系化合物を有効成分とするもの、トリアジン環系高縮合物塩の界面活性剤を有効成分とするもの、メチロールメラミン縮合物を有効成分とするもの、変性メチロールメラミン縮合物を有効成分とするもの、変性メチロールメラミン縮合物とカルボン酸系化合物を有効成分とするもの、スルホン化メラミン高縮合物塩を有効成分とするもの等を挙げることができる。
【００１３】
また含有される減水剤の状態は、液体でも可溶性粉体でも良い。本注入材の減水剤含有量は０．１〜５重量部とする。好ましくは、減水剤としてナフタレンスルホン酸系減水剤を単独使用する場合は０．２〜３重量部、減水剤としてナフタレンスルホン酸系減水剤とメラミンスルホン酸系減水剤を併用する場合はナフタレンスルホン酸系減水剤０．２〜３重量部とし、メラミンスルホン酸系減水剤はそれ以下の量とする。減水剤の含有量が０．１重量部未満ではスラリー中の微粒子凝集抑制効果が殆ど得られず浸透性が低下するので好ましくなく、また５重量部を超えると凝結時間が遅延し、強度発現性が低下することがあるので好ましくない。また、本発明の注入材では、ナフタレンスルホン酸系減水剤がメラミンスルホン酸系減水剤以外の減水剤と併用されることを妨げるものではなく、ナフタレンスルホン酸系減水剤の作用を減滅させることなく、本注入材の浸透性や強度発現性に支障を及ぼさない限り、他の減水剤との併用も許容される。
【００１４】
本発明の注入材には石膏を除く可溶性硫酸塩、可溶性チオ硫酸塩、可溶性亜硫酸塩の何れか１種以上が含有される。石膏を除く可溶性硫酸塩、可溶性チオ硫酸塩や亜硫酸塩は高い浸透性を保持しつつ、初期〜中期の強度発現性を向上促進する作用を付与する。ここで可溶性とは概ね常温で水に溶解できることを云う。本注入材に含有可能な石膏を除く可溶性硫酸塩は特に限定されないが、例えば硫酸ナトリウム、硫酸カリウム、硫酸水素ナトリウム、硫酸水素カリウム、硫酸第一鉄等を挙げることができ、また可溶性チオ硫酸塩も特に限定されないが、例えばチオ硫酸ナトリウム、チオ硫酸カリウム等を挙げることができ、更に可溶性亜硫酸塩も特に限定されるものではなく、例えば亜硫酸ナトリウム、亜硫酸カリウム、亜硫酸水素ナトリウム等を挙げることができる。石膏を除く可溶性硫酸塩、可溶性チオ硫酸塩、可溶性亜硫酸塩の総含有量は、０．１〜５重量部とする。０．１重量部未満では含有効果が乏しいので好ましくなく、また５重量部を超えると、浸透性を低下させずに初期〜中期強度発現性を向上することが困難となることがあるので好ましくない。
【００１５】
本発明の注入材には前記以外の成分を浸透性や強度発現性等の性状に支障を及ぼさない範囲で適宜含有することができる。含有可能な成分例を示すと、フライアッシュやシリカフューム等のポゾラン反応性物質、炭酸カルシウム、水酸化カルシウム等がある。
【００１６】
また、本発明の注入材は、石膏を除く可溶性硫酸塩、可溶性チオ硫酸塩及び可溶性亜硫酸塩の粒子を除いた注入材含有全粒子の９５体積％以上、好ましくは９７体積％以上、より好ましくは９８．５体積％以上、が粒径１０．５μｍ以下の粒子からなり、且つ粒径２．２μｍ以下の粒子が４５体積％以下、好ましくは３５体積％以下の含有となる注入材である。粒径１０．５μｍ以下の粒子の含有量が９５体積％未満では、粗粒分が多く含まれる可能性があり、土壌粒子間隙が粗粒で閉塞し易くなって浸透性が低下するので好ましくない。また粒径２．２μｍ以下の粒子含有量が４５体積％を超えると、スラリー中での粒子凝集化が生じ易くなり、浸透性がかなり低下することがあるので好ましくない。
【００１７】
本発明の注入材は、通常の方法により製造することができ、例えば、各成分の１種以上を混合粉砕する方法や、各成分を個別に粉砕した後、混合する方法が挙げられる。特に、個別に粉砕した後混合すると、浸透性、強度発現性がさらに良好な注入材を得ることができる。
【００１８】
また、本発明の注入材は、水性スラリー化して使用される。本発明の注入材１００重量部に対する水の添加量は、概ね１００〜１０００重量部が推奨される。スラリー化の方法は特段限定されるものではないが、一例を示すとグラウトミキサー等に前記例の如く作製した注入材と水を投入し、適度に混練を行なえば良い。
【００１９】
【実施例】
以下、実施例により本発明を具体的に詳しく説明する。尚、本発明はこれらの結果によって何等制限されるものではない。
【００２０】
［注入材の作製］
高炉水砕スラグ（新日本製鉄株式会社製）、普通ポルトランドセメント用クリンカ（太平洋セメント株式会社製）、無水石膏（セントラル硝子株式会社製）、中性無水ボウ硝（東ソー株式会社製）、硫酸第一鉄７水和物（試薬特級：和光純薬工業株式会社製）、亜硫酸ナトリウム（試薬特級：関東化学株式会社製）、チオ硫酸ナトリウム（試薬特級：関東化学株式会社製）、表１に表すａ〜ｅの減水剤から選定される材料を使用し、表２に表す含有量及び粒度分布となるように注入材を作製した。ここで、高炉水砕スラグ、普通ポルトランドセメント用クリンカ及び無水石膏については、チューブミルに一括投入して混合粉砕し、遠心分級機で所望の粒度に調整した。粒度調整した混合粉は他の使用材料と共にヘンシェルミキサーを用い、約５分程度乾式混合を行なった。尚、粒度測定はレーザー回折式粒度分布測定装置（ＨＥＬＯＳ＆ＲＯＤＯＳ）を用いて行ない、その粒度分布結果を示した表１記載の粒子含有率は、石膏を除く可溶性成分以外の粒状物質に対するものである。
【００２１】
【表１】

【００２２】
【表２】

【００２３】
［注入材の特性評価］
前記作製した各注入材を、水／注入材重量比３００％に調整して約１分間混練し、注入材スラリーを作製した。該スラリーを約２０℃の温度下で６０分間撹拌練り置きした後、撹拌装置を取り付けた圧力容器内に投入し、１．０Ｋｇｆ／ｃｍ^２の一定圧力で、垂直に立てたφ５×１００ｃｍアクリル管に間隙率３９％となるよう豊浦砂（平均粒径約２２５μｍ）を充填した供試体の下部より注入した。供試体砂層上部から流出したスラリー量をグラウト注入量として測定し、この値をもって浸透性を評価した。尚、供試体は注入前に水で飽和しておき、注入完了は注入開始から２０分以内とした。測定したグラウト注入量の結果を表３に表す。多く注入できたもの（グラウト注入量が多いもの）ほど注入浸透性が高い注入材である。また、スラリー硬化後、アクリル管から脱型した硬化供試体をφ５×１０ｃｍの円柱状に加工し、材齢４日まで養生した。これを地盤工学会基準「土の一軸圧縮試験方法」（Ｔ５１１）に準じて一軸圧縮強度の測定を行い、この測定値をもって初期〜中期強度発現性を評価した。一軸圧縮強度を測定結果も表３に表す。
【００２４】
【表３】

【００２５】
【発明の効果】
本発明の注入材は、強度発現性の低下が起らず、しかも非常に高い浸透性を有し、更にはこの浸透性をスラリー作製時から比較的長時間安定して保つことができるため施工作業の制約が軽減できる。本注入材は、特に、亀裂を含む岩盤や緩い砂地盤等の恒久的な強化や止水等に好適に用いることができる。[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an injection material used for improving soft ground, fragile rock, or the like, into a hard and strong one, or for reinforcing a foundation of a building or stopping water.
[0002]
[Prior art]
To make the ground and bedrock more rigid and robust, and to prevent liquefaction, the injection material containing hydraulic material as the main component is used as an aqueous slurry into the soil particle gaps in the ground and cracks in the bedrock before being used. Have been. It is necessary to particularly increase the permeability of the injected material to the ground to be injected, such as a ground with a small permeability coefficient.As such an injected material, a cement clinker with a considerably reduced maximum particle size and a blast furnace slag with a high specific surface area are effective. A so-called ultrafine particle-type injection material as a component is known. (For example, see Patent Document 1). However, since the ultrafine particle type injection material contains a large amount of fine particles having a particle size of about 2 μm or less, the fine particles are easily aggregated in the slurry, the permeability at the time of injection is reduced, and the active material of the injection material in the ground is reduced. Tends to cause density unevenness. For this reason, it has been practiced to adjust the particle size of the particles constituting the injection material to a specific range to improve the permeability at the time of slurry injection. (For example, see Patent Document 2). In addition, if a water reducing agent for cement is used in combination, the dispersibility can be increased and the agglomeration of the particles can be suppressed. Requires a large amount of a water reducing agent, and in order to make the time from slurry preparation to injection longer, it is necessary to further increase the amount of the water reducing agent. On the other hand, if the amount of the expensive water reducing agent is increased, there arises a problem that, in addition to an increase in material cost, the initial to mid-to-long term strength developability tends to decrease.
[0003]
[Patent Document 1]
Japanese Patent No. 2894529 [Patent Document 2]
JP-A-9-255378
[Problems to be solved by the invention]
An object of the present invention is to provide an injection material that exhibits extremely high permeability even when injected into a ground or the like having a low permeability coefficient and does not cause a decrease in strength development in the initial to middle stages even after the injection.
[0005]
[Means for Solving the Problems]
The inventors of the present invention have conducted various studies to solve the above problems, and as a result, defined the particle size of the slag-cement composition, and injected an aqueous slurry containing a specific water reducing agent into the ground having a low permeability coefficient. However, it exhibits extremely high permeability and can maintain this permeability stably for a relatively long period of time from the time of preparing the slurry. In addition, any one of soluble sulfate, soluble thiosulfate and soluble sulfite except gypsum can be used. The incorporation of more than one species was able to sufficiently prevent a decrease in strength development in the initial to middle stages while maintaining high permeability, thereby completing the present invention.
[0006]
That is, the present invention relates to (A) 50 to 90 parts by weight of slag, (B) 0.5 to 3 parts by weight of gypsum in terms of SO ₃ , (C) 10 to 50 parts by weight of cement clinker, (D) naphthalenesulfonic acid-based 0.1 to 5 parts by weight of a water reducing agent or a naphthalenesulfonic acid-based water reducing agent and a melaminesulfonic acid-based water reducing agent, and (E) at least one of soluble sulfates, soluble thiosulfates, and soluble sulfites other than gypsum. 1 to 5 parts by weight, wherein 95% by volume or more of the particles in the injection material excluding the particles of (E) are particles having a particle size of 10.5 μm or less; An injection material characterized in that particles having a size of 2 μm or less are 45% by volume or less.
[0007]
BEST MODE FOR CARRYING OUT THE INVENTION
The slag contained in the injection material of the present invention is not particularly limited except that it is in the form of powder, and examples thereof include blast furnace slag, sewage sludge melting slag, and municipal waste melting slag. Desirably, a slag having a high vitrification rate is good. For example, a blast furnace granulated slag which is rapidly cooled is suitable. The slag content in the injection material is 50 to 90 parts by weight. If the amount is less than 50 parts by weight, the permeability is unpreferably decreased, and if it exceeds 90 parts by weight, the coagulation ability is undesirably reduced.
[0008]
The gypsum contained in the injection material of the present invention may be any one or two or more of anhydrous gypsum, gypsum hemihydrate, and gypsum dihydrate, except that it is in the form of a powder. It may be what is called chemical gypsum. Gypsum is included solely to impart an action of increasing initial strength development by ettringite formation and also contribute to a hardening acceleration action. The gypsum content in the present injection material is, for example, when Portland cement or the like is compounded and contained, is the total content including the gypsum component contained in the cement, and is 0.5 to 3 parts by weight in terms of SO _3. And If the gypsum content is less than 0.5 parts by weight in terms of SO ₃ , the initial strength development is unfavorably low, and if it exceeds 3 parts by weight, the permeability is undesirably reduced.
[0009]
The cement clinker contained in the injection material of the present invention is obtained by calcining a cement raw material such as limestone at, for example, 1300 to 1450 ° C., provided that the hydration-reactive substance is the main generation phase. There is no particular limitation. As the content form of the cement clinker in the present injection material, except that the cement clinker is in a powder form, a cement clinker powder alone or a cement clinker containing such a cement clinker may be used. . In the latter case, the type of cement is not limited. The content of the cement clinker in the present injection material is 10 to 50 parts by weight. This content is the amount occupied by the clinker-equivalent component contained in the cement when injected as cement powder in the injected material, and when the cement clinker powder alone is also included, the amount is combined with the amount of the single substance. . If the content of the cement clinker is less than 10 parts by weight, the setting is excessively delayed, so that it is not preferable. If it exceeds 50 parts by weight, the permeability is remarkably reduced.
[0010]
The injection material of the present invention contains a water reducing agent. As the water reducing agent, a naphthalenesulfonic acid-based water reducing agent is indispensable. Preferably, a naphthalenesulfonic acid-based water reducing agent and a melaminesulfonic acid-based water reducing agent are used in combination. Such water reducing agents may be referred to as high performance water reducing agents, high performance AE water reducing agents or dispersants. By containing a naphthalenesulfonic acid-based water reducing agent, the permeability of the injection material can be significantly increased even with a small amount of use, and the aggregation time of the particles in the slurry can be reduced without substantially affecting the strength development in the initial to middle stages. It is possible to elongate. Further, by using a melamine sulfonic acid-based water reducing agent in addition to the naphthalene sulfonic acid-based water reducing agent, it is possible to significantly extend the time required for suppressing the aggregation of particles in the slurry, in particular.
[0011]
The naphthalenesulfonic acid-based water reducing agent that can be contained is not particularly limited, and includes, for example, those containing a high-condensate salt of naphthalenesulfonic acid formalin as an active ingredient, those containing a formalin condensate of sodium naphthalenesulfonic acid as an active ingredient, and sodium naphthalenesulfonic acid. The active ingredient is a salt formalin polycondensate, the active ingredient is a highly condensed aromatic sulfonic acid, the active ingredient is a modified lignin and a highly condensed aromatic sulfonic acid complex, and the active ingredient is an alkylallyl sulfonic acid. Those having an alkylallyl sulfonic acid salt as an active ingredient, those having an alkyl allyl sulfonic acid high condensate as an active ingredient, those having an alkyl allyl sulfonate high condensate as an active ingredient, formalin alkyl naphthalene sulfonic acid Condensate as active ingredient, naphthalenesulfonic acid-modified resin Nin condensate as active ingredient, naphthalene sulfonic acid modified lignin condensate and lignin as active ingredient, modified lignin and alkyl allyl sulfonic acid and active-active polymer as active ingredient, polyalkyl sulfone An active ingredient comprising an acid and a reactive polymer, an alkyl allyl sulfonic acid highly condensed product and a carboxyl group-containing polyvalent polymer as an active ingredient, an alkyl allyl sulfonate-modified lignin co-condensate and a modified lignin as an active ingredient Those having a lignin derivative and an alkyl allyl sulfonate as active ingredients, those having a polyalkyl allyl sulfone surfactant as an active ingredient, those having an alkyl allyl sulfonate formalin condensate as an active ingredient, polyalkyl Listed are those containing an allylsulfonic acid compound as an active ingredient. Door can be.
[0012]
The melamine sulfonic acid-based water reducing agent that can be contained is not particularly limited. For example, those containing a melamine sulfonic acid-based condensate as an active ingredient, those containing a melamine sulfonic acid-based compound as an active ingredient, melamine sulfonic acid-based compounds and polyols Those having a complex as an active ingredient, those having a highly condensed triazine-based compound as an active ingredient, those having a surfactant of a triazine ring-based high condensate salt as an active ingredient, those having a methylol melamine condensate as an active ingredient, Examples thereof include those containing a modified methylol melamine condensate as an active ingredient, those containing a modified methylol melamine condensate and a carboxylic acid-based compound as active ingredients, and those containing a sulfonated melamine high condensate salt as an active ingredient.
[0013]
The state of the water reducing agent contained may be liquid or soluble powder. The content of the water reducing agent in the injection material is 0.1 to 5 parts by weight. Preferably, when a naphthalenesulfonic acid-based water reducing agent is used alone as a water reducing agent, 0.2 to 3 parts by weight, and when a naphthalenesulfonic acid-based water reducing agent and a melaminesulfonic acid-based water reducing agent are used in combination as a water reducing agent, naphthalenesulfonic acid is used. The amount of the melamine sulfonic acid-based water reducing agent is 0.2 to 3 parts by weight, and the amount of the melamine sulfonic acid-based water reducing agent is less than that. When the content of the water reducing agent is less than 0.1 part by weight, the effect of suppressing the aggregation of fine particles in the slurry is hardly obtained, and the permeability is unfavorably lowered. Is undesirably reduced. In addition, the injection material of the present invention does not prevent the use of the naphthalenesulfonic acid-based water reducing agent in combination with a water reducing agent other than the melaminesulfonic acid-based water reducing agent, and reduces the action of the naphthalenesulfonic acid-based water reducing agent. In addition, as long as it does not affect the permeability and strength development of the present injection material, it can be used in combination with other water reducing agents.
[0014]
The injection material of the present invention contains at least one of soluble sulfate, soluble thiosulfate, and soluble sulfite except gypsum. Soluble sulfate, soluble thiosulfate, and sulfite other than gypsum impart an action of improving and promoting the initial to mid-stage strength development while maintaining high permeability. Here, "soluble" means that it can be dissolved in water at room temperature. The soluble sulfate except gypsum that can be contained in the present injection material is not particularly limited, and examples thereof include sodium sulfate, potassium sulfate, sodium hydrogen sulfate, potassium hydrogen sulfate, and ferrous sulfate. Although not particularly limited, for example, sodium thiosulfate, potassium thiosulfate and the like can be mentioned, and further, the soluble sulfite is not particularly limited, and examples thereof include sodium sulfite, potassium sulfite, and sodium hydrogen sulfite. . The total content of soluble sulfate, soluble thiosulfate, and soluble sulfite except gypsum is 0.1 to 5 parts by weight. If the amount is less than 0.1 part by weight, the content effect is poor, so that it is not preferable. If the amount exceeds 5 parts by weight, it is difficult to improve the initial to mid-term strength development without lowering the permeability, which is not preferable. .
[0015]
The injection material of the present invention can appropriately contain components other than the above as long as properties such as permeability and strength development are not affected. Examples of components that can be contained include pozzolan-reactive substances such as fly ash and silica fume, calcium carbonate, calcium hydroxide, and the like.
[0016]
Further, the injection material of the present invention is at least 95% by volume, preferably at least 97% by volume, more preferably at least 97% by volume of all particles containing the injection material except particles of soluble sulfate, soluble thiosulfate and soluble sulfite except gypsum. 98.5% by volume or more of particles having a particle size of 10.5 μm or less, and 45% by volume or less, preferably 35% by volume or less of particles having a particle size of 2.2 μm or less. If the content of the particles having a particle diameter of 10.5 μm or less is less than 95% by volume, a large amount of coarse particles may be contained, and the soil particle gaps are likely to be clogged with coarse particles, resulting in a decrease in permeability. . On the other hand, if the content of particles having a particle size of 2.2 μm or less exceeds 45% by volume, particle agglomeration in the slurry is likely to occur, and the permeability may be considerably reduced, which is not preferable.
[0017]
The injection material of the present invention can be produced by an ordinary method, and examples thereof include a method of mixing and pulverizing at least one of the components, and a method of pulverizing each component individually and then mixing. In particular, when individually pulverized and then mixed, it is possible to obtain an injection material having better permeability and strength.
[0018]
The injection material of the present invention is used in the form of an aqueous slurry. The amount of water to be added to 100 parts by weight of the injection material of the present invention is generally recommended to be 100 to 1000 parts by weight. The method for slurrying is not particularly limited, but as an example, the injection material and water produced as in the above example may be charged into a grout mixer or the like, and kneaded appropriately.
[0019]
【Example】
Hereinafter, the present invention will be described in detail with reference to examples. The present invention is not limited by these results.
[0020]
[Preparation of injection material]
Granulated blast furnace slag (manufactured by Nippon Steel Corporation), clinker for ordinary Portland cement (manufactured by Taiheiyo Cement Co., Ltd.), anhydrous gypsum (manufactured by Central Glass Co., Ltd.), neutral anhydrous borate (manufactured by Tosoh Corporation), sulfuric acid Ferrous heptahydrate (special grade reagent: manufactured by Wako Pure Chemical Industries, Ltd.), sodium sulfite (special grade reagent: manufactured by Kanto Chemical Co., Ltd.), sodium thiosulfate (special grade reagent: manufactured by Kanto Chemical Co., Ltd.), shown in Table 1. Using materials selected from the water reducing agents a to e, injection materials were prepared so as to have the contents and particle size distributions shown in Table 2. Here, the granulated blast furnace slag, the clinker for ordinary Portland cement, and the anhydrous gypsum were collectively charged into a tube mill, mixed and pulverized, and adjusted to a desired particle size by a centrifugal classifier. The mixed powder having the adjusted particle size was dry-mixed for about 5 minutes with a Henschel mixer together with other materials used. The particle size was measured using a laser diffraction particle size distribution analyzer (HELOS & RODOS), and the particle content shown in Table 1 showing the results of the particle size distribution is based on the particulate matter other than the soluble component except gypsum.
[0021]
[Table 1]

[0022]
[Table 2]

[0023]
[Characteristic evaluation of injection material]
Each of the prepared injection materials was adjusted to a water / injection material weight ratio of 300% and kneaded for about 1 minute to prepare an injection material slurry. The slurry was stirred and kneaded at a temperature of about 20 ° C. for 60 minutes and then charged into a pressure vessel equipped with a stirrer, and was vertically erected at a constant pressure of 1.0 Kgf / cm ² at a φ5 × 100 cm acrylic tube. Was injected from the lower part of the specimen filled with Toyoura sand (average particle size: about 225 μm) so that the porosity was 39%. The amount of slurry flowing out from the upper part of the test sample sand layer was measured as grout injection amount, and this value was used to evaluate permeability. The specimen was saturated with water before the injection, and the injection was completed within 20 minutes from the start of the injection. Table 3 shows the results of the measured grout injection amount. The injection material that can be injected more (the grout injection amount is larger) has higher injection permeability. Further, after the slurry was cured, the cured specimen removed from the acrylic pipe was processed into a column of φ5 × 10 cm, and was cured until the age of 4 days. This was measured for uniaxial compressive strength in accordance with the Japanese Geotechnical Society standard “Uniaxial compressive test method for soil” (T511), and the initial to mid-term strength development was evaluated based on this measured value. Table 3 also shows the measurement results of the uniaxial compressive strength.
[0024]
[Table 3]

[0025]
【The invention's effect】
The injection material of the present invention does not cause a decrease in strength development, and has a very high permeability, and furthermore, this permeability can be stably maintained for a relatively long time from the time of slurry preparation, so that Work restrictions can be reduced. The present injection material can be suitably used particularly for permanent strengthening of a rock mass containing cracks, loose sandy ground, or the like, or for stopping water.

Claims

(A) 50 to 90 parts by weight of slag, (B) 0.5 to 3 parts by weight of gypsum in terms of SO ₃ , (C) 10 to 50 parts by weight of cement clinker, (D) naphthalenesulfonic acid-based water reducing agent or naphthalenesulfone 0.1 to 5 parts by weight of at least one of an acid-based water reducing agent and a melamine sulfonic acid-based water reducing agent and at least one of soluble sulfates, soluble thiosulfates, and soluble sulfites other than gypsum (E) , Wherein 95% by volume or more of the particles in the injection material except for the particles of (E) are particles having a particle size of 10.5 μm or less, and particles having a particle size of 2.2 μm or less. An injection material characterized by being 45% by volume or less.