岩溶地区高压帷幕灌浆试验研究
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摘要
岩体是由岩块及其裂隙组成的，对岩溶地区的岩体尚包括沿结
构面发育而成的溶蚀孔、洞，一般来说，岩石的透水性很小，岩体
的透水性主要决定于裂隙的渗透性大小。采用钻孔水泥灌浆封堵岩
体中的缝隙而形成阻水帷幕，达到减少渗漏量和降低渗透压力的目
的，是水利水电工程基础处理的重要手段之一。高压灌浆(即孔口
封闭灌浆法)自乌江渡电站首次采用并取得成功后，在岩溶地区得
到了迅速的推广，集累了十分丰富的实践经验。但由于岩溶地质条
件的复杂性，且高压灌浆作为一项技术和工艺，在设计、施工、质
量检验及效果评价等方面，仍然处在不断发展的过程中，正是基于
以上两个方面的考虑，本课题结合响水河水库高压帷幕灌浆工程进
行了大规模的试验研究，一方面指导帷幕灌浆的设计与施工，达到
优化设计方案的目的；另一方面对试验资料进行分析研究，以期对
同类工程有所助益。主要工作和结论如下：
1、全面回顾了国内外岩溶地区水库防渗的现状和发展趋势。
2、采取综合手段进行勘察论证，进一步查清各试验区的工程地
质条件。
3、岩溶地层属强透水岩体且具有较好的可灌性。岩体透水率与
可灌性之间一般存在以下三种组合关系：高单位吸水率与大吃浆量
的组合，灌浆是必需的；低单位吸水率与小吃浆量的组合，没有必
要灌浆；低单位吸水率与大吃浆量的组合，应进行灌浆处理，但应
适当控制灌浆压力和耗浆量。
4、针对浅表层岩体风化破碎严重易形成浆液大量流失的地段，
提出了改进的孔口封闭灌浆法，即深部孔口封闭灌浆法，既可满足
帷幕的施工质量要求，又减少了水泥的无益消耗，可产生明显的经
济效益.
5、在总长为979.32m长的帷幕段中，初设批复方案的双排帷幕
总长为879.32m，占帷幕总长的92%，根据灌浆试验研究成果优化设
计后，双排帷幕长度减少至245.“m，仅占帷幕总长度的25%。钻孔
密度也由原来的0.slm/mZ降至o.64n扩mZ，节约工程投资447.35万元。
6、单排帷幕的孔距在1.4一1.8m之间，双排帷幕的孔距以Zm
为宜;灌浆压力在地表以下前三段一般为1一1.SMpa，第四段以下按
4一SMPa控制;对大部分孔段而言，开灌水灰比可定为2或1。
7、岩体单位吸水率与单位注入量之间普遍存在一定的相关关
系，而岩体完势性指数及岩体波速与单位注入量之间不存在相关关
系。
8、在利用岩体完整性指数评价高压帷幕灌浆效果时，采用本课
题提出的“八级分档Kv值与定性划分岩体完整程度对应关系表”，
灌浆后的岩体完整程度较灌前均提高了一个等级。同时用q《stu防
渗标准所进行的检查孔压水试验合格率为100%。
9、对设置于深帷幕之间的灌浆平洞，为适应灌浆压力的要求，
对平洞进行全断面衬砌及固结灌浆是必要的;对平洞底板即为帷幕
顶界的灌浆平洞，若裸洞的稳定及安全均有保证，仅进行平洞底板
硅衬砌(厚0.5一0.6m)已可满足高压灌浆要求，从而可以省去昂贵
的平洞衬砌及固结灌浆费用。
The rock mass is made up with rock and cracks, however, in the Carst region' s the rock mass also include the hole and cave develop for corrosion. Generally, the rock is impermeable, and the permeability of the rock mass depends on the permeability of cracks. Boring, grouting and finally forming an impervious curtain in the rock mass with cracks, that is one of the most popular methods of the foundation seepage control at hydraulic and hydroelectric engineering.
Since first used in the WuJiangDu Hydraulic power station with success, high-pressure grouting (orifice-closed grouting method) spreads rapidly in the Carst region and lots of experience are accumulated. However, the geologic structure of the Carstic formation is complicated and the design, construction, quality testing method of the high-pressure grouting is developing rapidly. We have engaged lots of experiments and studies in XiangShuiRiver Reservoir on this subject. One of the purposes subject is to guide the design, construction of the curtain grouting in the XiangShuiRiver Reservoir and optimize the grouting Design, the other is to be a reference example for other similar engineering. The main points of this topic as follows:
1. Review the changing at home and abroad of the reservoir' s seepage control on the Carst region.
2. Adopt varied exploration method to check up on geologic structure of the all demonstration area.
3. The Carstic formation is permeable layer and has quite good placeability, its relations of the water permeabitity and placeability have three types as follows:
High unit-absorption rate with big grout consumption, the grouting is necessary; low unit-absorption rate with little grout consumption, the grouting is no need; Low unit-absorption rate with big grout consumption, grouting is no need combining with control the grouting pressure and grout consumption.
4. Bring forward a improved orifice-closed grouting method (depths orifice-closed grouting method) due to broken rock on the
earth' s surface.
5. There are 979.32 meter long to the curtain of the XiangShuiRiver Reservoir include 879.32 meter' s long double row curtain (about 92 percent) in the original design. By optimizing the design according to the grouting test, the double row curtain was cut down to 245.66 meter length (25 per cent of them), The density of the bore hole have from 0.81m/m2 reduced to 0.64m/m2.Total save 4.47 million RMB cost of the project.
6. The distance of the single-row curtain grout hole is between 1.4 to 1.8 meter, and 2.0 meter is suitable for the double-row curtain; the grouting pressure generally is 1.0 to 1.5 MPa at the first three grout compartment, then grouting pressure of under the fourth control
in 4 to 5 MPa; For mast grout compartments, a water-cement ratio of 2 or 1 may used in the first grouting.
7. There obvious dependency relation between the unit-absorption rate and grout consumption, general there are bearing relation, but no obvious dependency relation between the index of the rock mass integrity and grout consumption.
8. When using the index of the rock mass integrity, the index of the grouted rock mass integrity has raised one rank according to the theory and stand raised by this article.
9. When grouting gallery of depth-curtain, lining and consolidation grouting to full-face of the gallery is necessary to meet the needs of the grouting pressure. But in the condition that the gallery base plate is the head of the curtain, and bare rock mass was stable enough then only lining to the gallery' s base plate is necessary. And the needs of the high-pressure grouting are satisfied. Thus large cost of the lining and consolidation grouting can be saved.
构面发育而成的溶蚀孔、洞，一般来说，岩石的透水性很小，岩体
的透水性主要决定于裂隙的渗透性大小。采用钻孔水泥灌浆封堵岩
体中的缝隙而形成阻水帷幕，达到减少渗漏量和降低渗透压力的目
的，是水利水电工程基础处理的重要手段之一。高压灌浆(即孔口
封闭灌浆法)自乌江渡电站首次采用并取得成功后，在岩溶地区得
到了迅速的推广，集累了十分丰富的实践经验。但由于岩溶地质条
件的复杂性，且高压灌浆作为一项技术和工艺，在设计、施工、质
量检验及效果评价等方面，仍然处在不断发展的过程中，正是基于
以上两个方面的考虑，本课题结合响水河水库高压帷幕灌浆工程进
行了大规模的试验研究，一方面指导帷幕灌浆的设计与施工，达到
优化设计方案的目的；另一方面对试验资料进行分析研究，以期对
同类工程有所助益。主要工作和结论如下：
1、全面回顾了国内外岩溶地区水库防渗的现状和发展趋势。
2、采取综合手段进行勘察论证，进一步查清各试验区的工程地
质条件。
3、岩溶地层属强透水岩体且具有较好的可灌性。岩体透水率与
可灌性之间一般存在以下三种组合关系：高单位吸水率与大吃浆量
的组合，灌浆是必需的；低单位吸水率与小吃浆量的组合，没有必
要灌浆；低单位吸水率与大吃浆量的组合，应进行灌浆处理，但应
适当控制灌浆压力和耗浆量。
4、针对浅表层岩体风化破碎严重易形成浆液大量流失的地段，
提出了改进的孔口封闭灌浆法，即深部孔口封闭灌浆法，既可满足
帷幕的施工质量要求，又减少了水泥的无益消耗，可产生明显的经
济效益.
5、在总长为979.32m长的帷幕段中，初设批复方案的双排帷幕
总长为879.32m，占帷幕总长的92%，根据灌浆试验研究成果优化设
计后，双排帷幕长度减少至245.“m，仅占帷幕总长度的25%。钻孔
密度也由原来的0.slm/mZ降至o.64n扩mZ，节约工程投资447.35万元。
6、单排帷幕的孔距在1.4一1.8m之间，双排帷幕的孔距以Zm
为宜;灌浆压力在地表以下前三段一般为1一1.SMpa，第四段以下按
4一SMPa控制;对大部分孔段而言，开灌水灰比可定为2或1。
7、岩体单位吸水率与单位注入量之间普遍存在一定的相关关
系，而岩体完势性指数及岩体波速与单位注入量之间不存在相关关
系。
8、在利用岩体完整性指数评价高压帷幕灌浆效果时，采用本课
题提出的“八级分档Kv值与定性划分岩体完整程度对应关系表”，
灌浆后的岩体完整程度较灌前均提高了一个等级。同时用q《stu防
渗标准所进行的检查孔压水试验合格率为100%。
9、对设置于深帷幕之间的灌浆平洞，为适应灌浆压力的要求，
对平洞进行全断面衬砌及固结灌浆是必要的;对平洞底板即为帷幕
顶界的灌浆平洞，若裸洞的稳定及安全均有保证，仅进行平洞底板
硅衬砌(厚0.5一0.6m)已可满足高压灌浆要求，从而可以省去昂贵
的平洞衬砌及固结灌浆费用。
The rock mass is made up with rock and cracks, however, in the Carst region' s the rock mass also include the hole and cave develop for corrosion. Generally, the rock is impermeable, and the permeability of the rock mass depends on the permeability of cracks. Boring, grouting and finally forming an impervious curtain in the rock mass with cracks, that is one of the most popular methods of the foundation seepage control at hydraulic and hydroelectric engineering.
Since first used in the WuJiangDu Hydraulic power station with success, high-pressure grouting (orifice-closed grouting method) spreads rapidly in the Carst region and lots of experience are accumulated. However, the geologic structure of the Carstic formation is complicated and the design, construction, quality testing method of the high-pressure grouting is developing rapidly. We have engaged lots of experiments and studies in XiangShuiRiver Reservoir on this subject. One of the purposes subject is to guide the design, construction of the curtain grouting in the XiangShuiRiver Reservoir and optimize the grouting Design, the other is to be a reference example for other similar engineering. The main points of this topic as follows:
1. Review the changing at home and abroad of the reservoir' s seepage control on the Carst region.
2. Adopt varied exploration method to check up on geologic structure of the all demonstration area.
3. The Carstic formation is permeable layer and has quite good placeability, its relations of the water permeabitity and placeability have three types as follows:
High unit-absorption rate with big grout consumption, the grouting is necessary; low unit-absorption rate with little grout consumption, the grouting is no need; Low unit-absorption rate with big grout consumption, grouting is no need combining with control the grouting pressure and grout consumption.
4. Bring forward a improved orifice-closed grouting method (depths orifice-closed grouting method) due to broken rock on the
earth' s surface.
5. There are 979.32 meter long to the curtain of the XiangShuiRiver Reservoir include 879.32 meter' s long double row curtain (about 92 percent) in the original design. By optimizing the design according to the grouting test, the double row curtain was cut down to 245.66 meter length (25 per cent of them), The density of the bore hole have from 0.81m/m2 reduced to 0.64m/m2.Total save 4.47 million RMB cost of the project.
6. The distance of the single-row curtain grout hole is between 1.4 to 1.8 meter, and 2.0 meter is suitable for the double-row curtain; the grouting pressure generally is 1.0 to 1.5 MPa at the first three grout compartment, then grouting pressure of under the fourth control
in 4 to 5 MPa; For mast grout compartments, a water-cement ratio of 2 or 1 may used in the first grouting.
7. There obvious dependency relation between the unit-absorption rate and grout consumption, general there are bearing relation, but no obvious dependency relation between the index of the rock mass integrity and grout consumption.
8. When using the index of the rock mass integrity, the index of the grouted rock mass integrity has raised one rank according to the theory and stand raised by this article.
9. When grouting gallery of depth-curtain, lining and consolidation grouting to full-face of the gallery is necessary to meet the needs of the grouting pressure. But in the condition that the gallery base plate is the head of the curtain, and bare rock mass was stable enough then only lining to the gallery' s base plate is necessary. And the needs of the high-pressure grouting are satisfied. Thus large cost of the lining and consolidation grouting can be saved.
引文
[1] 邹成杰．水利水电岩溶工程地质．北京：水利电力出版社，1994。
[2] 水工建筑物水泥灌浆施工技术规范SL62-94．北京：水利水电出版社，1994。
[3] G.Lombardi and Deere. Grouting design and,control using the GIN Principle. 1998.
[4] 于明鑫．江垭大坝帷幕灌浆试验及灌浆方案选择．北京：水利水电技术，1998第2期，43～44。
[5] 响水河水库物探试验孔井下电视分析报告．昆明岩土工程公司，2002．9。
[6] M.Oda etal. "Pirmeability tensor of jointed granite at Stripa Mine" ,Proc.6th Int.cong. Rock Mech,PP.203～206(1987).
[7] 林韵梅．岩体基本质量定量分级标准BQ公式的研究．岩土工程学报，1999第4期，481～485。
[8] 马国彦．水利水电工程灌浆与地下水排水．北京：水利水电出版社，2001，80～93。
[9] 水工建筑物水泥灌浆施工技术规范DLT5148-2001．北京：电力出版社，2002，77～78。
[10] 李瓒．砼拱坝设计．北京：电力出版社，2000，376～377。
[11] 王世夏．水工设计的理论和方法．北京：水利水电出版社，2000，443。
[12] 工程岩体分极标准GB50218～94．北京：计划出版社，1995，7～8。
[13] 富源县响水河水库帷幕灌浆工程试验报告．云南省水利工程有限公司第三公司，2002．12，33。
[14] 白永年．土石坝加固．北京：水利电力出版社，1992，726～742。
[15] 响水河水库除险加固工程帷幕灌浆优化设计报告．云南省曲靖市水利电力勘测设计研究院，2003．4，17～18。
[2] 水工建筑物水泥灌浆施工技术规范SL62-94．北京：水利水电出版社，1994。
[3] G.Lombardi and Deere. Grouting design and,control using the GIN Principle. 1998.
[4] 于明鑫．江垭大坝帷幕灌浆试验及灌浆方案选择．北京：水利水电技术，1998第2期，43～44。
[5] 响水河水库物探试验孔井下电视分析报告．昆明岩土工程公司，2002．9。
[6] M.Oda etal. "Pirmeability tensor of jointed granite at Stripa Mine" ,Proc.6th Int.cong. Rock Mech,PP.203～206(1987).
[7] 林韵梅．岩体基本质量定量分级标准BQ公式的研究．岩土工程学报，1999第4期，481～485。
[8] 马国彦．水利水电工程灌浆与地下水排水．北京：水利水电出版社，2001，80～93。
[9] 水工建筑物水泥灌浆施工技术规范DLT5148-2001．北京：电力出版社，2002，77～78。
[10] 李瓒．砼拱坝设计．北京：电力出版社，2000，376～377。
[11] 王世夏．水工设计的理论和方法．北京：水利水电出版社，2000，443。
[12] 工程岩体分极标准GB50218～94．北京：计划出版社，1995，7～8。
[13] 富源县响水河水库帷幕灌浆工程试验报告．云南省水利工程有限公司第三公司，2002．12，33。
[14] 白永年．土石坝加固．北京：水利电力出版社，1992，726～742。
[15] 响水河水库除险加固工程帷幕灌浆优化设计报告．云南省曲靖市水利电力勘测设计研究院，2003．4，17～18。