向家坝地下厂房围岩稳定分析和支护设计研究
|
摘要
向家坝水电站右岸地下厂房安装4台单机容量为75万kW的机组,主厂房开挖跨度达到31.40m/33.40m(岩锚梁上下),其开挖跨度为目前国内已建、在建和拟建电站中最大的,洞室围岩倾角平缓且含有开采历史的煤层,2级软弱结构面发育,水文地质条件复杂,因而地下洞室的围岩稳定和支护设计是向家坝水电站设计的关键技术问题之一,直接关系到工程安全和投资。因此有必要进行洞室围岩稳定分析计算,分析围岩应力变形特点,为支护设计提供数值依据,从而达到优化设计的目的。本文主要研究了地下洞室支护设计方法和围岩稳定分析方法等问题。
首先采取规程规范、Q系统和类似工程及工程经验等方法,论证向家坝地下厂房采用锚喷支护措施是可行的,并初拟主要洞室的支护参数,具体分析主要洞室工程地质特点,结合块体稳定分析成果,提出主厂房和主变洞顶拱及边墙采取系统预应力锚索等加强支护措施,采用平面和三维有限元等方法进行支护参数比较,从而提出主要洞室的支护型式和参数。
为对地下洞室围岩稳定有一个整体论证,分析厂区地质构造和实测地应力成果,进行了初始地应力场反演分析;根据洞室群布置特点,进行了开挖程序研究;然后采取三维弹塑性损伤有限元分析进行洞室围岩稳定分析,包括渗流场对围岩稳定的影响,综合评价地下洞室的稳定条件。
围岩稳定分析成果表明,向家坝地下厂房围岩整体稳定性较好。
The right underground powerhouse of Xiangjiaba Hydropower Station is installed with four units of installed capacity 750MW each; the excavated span of the machine hall reaches 31.40m/33.40m (up and down the rock anchored crane beam), which is the largest one among the completed, under construction and planned projects. The surround rock of the underground chambers is of slight dip angle and contains coal layers that had been mined in the history, in which the grade II weak structures develops and hydrological geology condition is complex. The stable of surround rock and supporting design of underground chambers is one of key technologies concerned of the design of Xiangjiaba Hydropower Station; it may affect the safety and investment of the project. So it is necessary to conduct calculation and analyses on the surround rock of the underground chambers, to analyses the stress and deformation characteristics of surround rock is to provide proofs for the supporting design to realize design optimization. This thesis focuses on the studying methods of the supporting design and analyses on the surround rock.Firstly it is to demonstrated that adopting the supporting of anchoring and shotcrete is feasible by adopting methods of codes, specifications, Q system, similar projects and other projects experiences, then to put forward adopting strengthening supporting measures such as pre-stressed anchorage ropes for the arch top of machine hall and main transformer chamber and the side walls through determining the supporting parameters and analyzing the engineering geology characters of main chambers as well as considering the analyses results of rock block stable, at last the supporting types and parameters of main underground chambers are suggested after the parameter comparison has been completed by the methods of plan and three-dimension finite element.In order to conduct a general reasoning on the stable of underground surround chamber, the results of geological structure and site crust stress in the powerhouse area have been analyzed and counter analyses on the primary crust stress field has also been conducted; excavation process has been studied according to the arrangement character of underground chambers; then the stable analyses of surround rock has been done by adopting three-dimension elastic plastic damnification finite element with consideration of the affection of seepage field to surround rock stable, finally the stable condition of underground chambers has synthetically been appraised.The stable analyses results for the surround rock of underground chambers indicate that the whole stability of surround rock of underground powerhouse is relatively good.
首先采取规程规范、Q系统和类似工程及工程经验等方法,论证向家坝地下厂房采用锚喷支护措施是可行的,并初拟主要洞室的支护参数,具体分析主要洞室工程地质特点,结合块体稳定分析成果,提出主厂房和主变洞顶拱及边墙采取系统预应力锚索等加强支护措施,采用平面和三维有限元等方法进行支护参数比较,从而提出主要洞室的支护型式和参数。
为对地下洞室围岩稳定有一个整体论证,分析厂区地质构造和实测地应力成果,进行了初始地应力场反演分析;根据洞室群布置特点,进行了开挖程序研究;然后采取三维弹塑性损伤有限元分析进行洞室围岩稳定分析,包括渗流场对围岩稳定的影响,综合评价地下洞室的稳定条件。
围岩稳定分析成果表明,向家坝地下厂房围岩整体稳定性较好。
The right underground powerhouse of Xiangjiaba Hydropower Station is installed with four units of installed capacity 750MW each; the excavated span of the machine hall reaches 31.40m/33.40m (up and down the rock anchored crane beam), which is the largest one among the completed, under construction and planned projects. The surround rock of the underground chambers is of slight dip angle and contains coal layers that had been mined in the history, in which the grade II weak structures develops and hydrological geology condition is complex. The stable of surround rock and supporting design of underground chambers is one of key technologies concerned of the design of Xiangjiaba Hydropower Station; it may affect the safety and investment of the project. So it is necessary to conduct calculation and analyses on the surround rock of the underground chambers, to analyses the stress and deformation characteristics of surround rock is to provide proofs for the supporting design to realize design optimization. This thesis focuses on the studying methods of the supporting design and analyses on the surround rock.Firstly it is to demonstrated that adopting the supporting of anchoring and shotcrete is feasible by adopting methods of codes, specifications, Q system, similar projects and other projects experiences, then to put forward adopting strengthening supporting measures such as pre-stressed anchorage ropes for the arch top of machine hall and main transformer chamber and the side walls through determining the supporting parameters and analyzing the engineering geology characters of main chambers as well as considering the analyses results of rock block stable, at last the supporting types and parameters of main underground chambers are suggested after the parameter comparison has been completed by the methods of plan and three-dimension finite element.In order to conduct a general reasoning on the stable of underground surround chamber, the results of geological structure and site crust stress in the powerhouse area have been analyzed and counter analyses on the primary crust stress field has also been conducted; excavation process has been studied according to the arrangement character of underground chambers; then the stable analyses of surround rock has been done by adopting three-dimension elastic plastic damnification finite element with consideration of the affection of seepage field to surround rock stable, finally the stable condition of underground chambers has synthetically been appraised.The stable analyses results for the surround rock of underground chambers indicate that the whole stability of surround rock of underground powerhouse is relatively good.
引文
1.中华人民共和国水利部,水电站厂房设计规范,SL266-2001,北京:中国水利水电出版社,2005
2.中华人民共和国建设部,锚杆喷射混凝土支护技术规范,GB50056-2001,北京:中国计划出版社,2001
3.谷兆祺,彭守拙,李仲奎,地下洞室工程,北京:清华大学出版社,1994
4.周维垣主编,高等岩石力学,北京:水利电力出版社,1989
5.蒋友谅,非线性有限元法,北京:北京工业学院出版社,1988
6.刘宁,卓家寿,基于三维弹塑性随机有限元的可靠度计算,水利学报,1996(9):53-62
7.水利水电规划设计总院,水利水电地下建筑物情报网编,水利水电工程地下建筑物设计手册,成都:四川科学技术出版社,1993
8.长江水利委员会,三峡工程专题信息资料,国内外大型地下水电站设计及施工技术,长江水利委员会信息研究中心,1997
9.谷兆祺主编,挪威水电工程经验介绍,北京:水利电力出版社,1985
10.杨述仁、周文铎等编,地下水电站厂房设计,北京:水利电力出版社,1993
11.王勖成、邵敏编,有限单元法基本原理与数值方法,清华大学出版社,1988
12.叶志明、刘红欣,国外几种大型有限元软件(FEAS)简介,计算力学学报,1997(1)
13.项阳、平杨、葛修润,面向对象有限元法在岩土工程中的应用,岩土力学,Vol.21 No.4,Dec.2000
14.汪启友,夏兴等,锚网喷联合支护在软岩土断面交叉点中的应用[J],.建材技术,2000,12(6):18-19
15.张林,马衍泉,高边坡稳定的三维地质力学模型试验研究[J],水电站设计,1994,10(3):39-44
16.王思敬、杨志法、傅冰骏,中国岩石力学与岩土工程的世纪成就与展望[A],第八次全国岩石力学与工程学术大会论文集[C],2004,1-9
17.国家电力公司成都勘测设计研究院,超大型地下洞室群合理布置及围岩稳定研究[R],“九五”国家科技攻关项目96-221-05-03专题报告,成都:成都勘测设计研究院,2000
18.中南勘测设计研究院,向家坝地下厂房洞室群围岩稳定与支护设计专题研究 报告,长沙:中南勘测设计研究院,2004
19.成都勘测设计研究院,溪落渡水电站地下厂房围岩稳定分析报告,成都:成都勘测设计研究院,2003
20.中南勘测设计研究院,龙滩水电站地下厂房围岩稳定分析专题研究报告,长沙:中南勘测设计研究院,2002
21.陈霞龄,韩伯鲤,梁克读,地下洞群围岩稳定的试验研究[J],武汉水利电力大学学报,1994,27(1):17-23
22.郭舜年,二滩水电站导流隧洞围岩与支护系统的地质力学平面模型试验研究[J],水电站设计,1997,13(2):95-99,105
23.刘宁,工程随机力学及可靠理论的若干问题(上),河海大学学报,99.5
24.刘宁,地下洞室围岩稳定的非线性随机有限元分析,固体力学学报,力学计算专辑,99
25.钱向东,复杂岩石稳定分析的弹塑性极限平衡法,河海大学学报,99.6
26.章青,有限元分析中开挖释放荷载的正确计算,河海大学学报,99.3
27. Nagai Tetsuo, Kunimura Shogo, Sun J. Behaviour of Jointed Rock Masses Around an Underground Opening Under Excavation Using Large-Scale Physical Model Tests[A], Proceedings of the Symposium on Rock Mechanics[C]. Wuhan, China, 1996, 27: 116-120
28. Zhao Z Y, Ye Y, Tao Z Y. Surrounding rock stability of the underground openings[A], Proc. Int. Symposium on Tunneling for Water Resources & Power Projects[C], NewDelhi, India, 1988, 1: 225-229
29. Kim S H, Burd H J. Model testing of closely spaced tunnels in clay[J], Geo-technique, 1998, 48(3): 375-388
30. Liu P, Liu K G. Selection of the random field mash in finite element reliability analysis[J], Journal of Engineering Mechanice, 1993, 119(4): 667-680
31. FENG Xia-ting, WANG Yong-jia. A neural network model on real-time prediction of roof pressure in coal mines[J], international Journal of Rock Mechanics and Mining Science. 1996, 33(6): 647-653
2.中华人民共和国建设部,锚杆喷射混凝土支护技术规范,GB50056-2001,北京:中国计划出版社,2001
3.谷兆祺,彭守拙,李仲奎,地下洞室工程,北京:清华大学出版社,1994
4.周维垣主编,高等岩石力学,北京:水利电力出版社,1989
5.蒋友谅,非线性有限元法,北京:北京工业学院出版社,1988
6.刘宁,卓家寿,基于三维弹塑性随机有限元的可靠度计算,水利学报,1996(9):53-62
7.水利水电规划设计总院,水利水电地下建筑物情报网编,水利水电工程地下建筑物设计手册,成都:四川科学技术出版社,1993
8.长江水利委员会,三峡工程专题信息资料,国内外大型地下水电站设计及施工技术,长江水利委员会信息研究中心,1997
9.谷兆祺主编,挪威水电工程经验介绍,北京:水利电力出版社,1985
10.杨述仁、周文铎等编,地下水电站厂房设计,北京:水利电力出版社,1993
11.王勖成、邵敏编,有限单元法基本原理与数值方法,清华大学出版社,1988
12.叶志明、刘红欣,国外几种大型有限元软件(FEAS)简介,计算力学学报,1997(1)
13.项阳、平杨、葛修润,面向对象有限元法在岩土工程中的应用,岩土力学,Vol.21 No.4,Dec.2000
14.汪启友,夏兴等,锚网喷联合支护在软岩土断面交叉点中的应用[J],.建材技术,2000,12(6):18-19
15.张林,马衍泉,高边坡稳定的三维地质力学模型试验研究[J],水电站设计,1994,10(3):39-44
16.王思敬、杨志法、傅冰骏,中国岩石力学与岩土工程的世纪成就与展望[A],第八次全国岩石力学与工程学术大会论文集[C],2004,1-9
17.国家电力公司成都勘测设计研究院,超大型地下洞室群合理布置及围岩稳定研究[R],“九五”国家科技攻关项目96-221-05-03专题报告,成都:成都勘测设计研究院,2000
18.中南勘测设计研究院,向家坝地下厂房洞室群围岩稳定与支护设计专题研究 报告,长沙:中南勘测设计研究院,2004
19.成都勘测设计研究院,溪落渡水电站地下厂房围岩稳定分析报告,成都:成都勘测设计研究院,2003
20.中南勘测设计研究院,龙滩水电站地下厂房围岩稳定分析专题研究报告,长沙:中南勘测设计研究院,2002
21.陈霞龄,韩伯鲤,梁克读,地下洞群围岩稳定的试验研究[J],武汉水利电力大学学报,1994,27(1):17-23
22.郭舜年,二滩水电站导流隧洞围岩与支护系统的地质力学平面模型试验研究[J],水电站设计,1997,13(2):95-99,105
23.刘宁,工程随机力学及可靠理论的若干问题(上),河海大学学报,99.5
24.刘宁,地下洞室围岩稳定的非线性随机有限元分析,固体力学学报,力学计算专辑,99
25.钱向东,复杂岩石稳定分析的弹塑性极限平衡法,河海大学学报,99.6
26.章青,有限元分析中开挖释放荷载的正确计算,河海大学学报,99.3
27. Nagai Tetsuo, Kunimura Shogo, Sun J. Behaviour of Jointed Rock Masses Around an Underground Opening Under Excavation Using Large-Scale Physical Model Tests[A], Proceedings of the Symposium on Rock Mechanics[C]. Wuhan, China, 1996, 27: 116-120
28. Zhao Z Y, Ye Y, Tao Z Y. Surrounding rock stability of the underground openings[A], Proc. Int. Symposium on Tunneling for Water Resources & Power Projects[C], NewDelhi, India, 1988, 1: 225-229
29. Kim S H, Burd H J. Model testing of closely spaced tunnels in clay[J], Geo-technique, 1998, 48(3): 375-388
30. Liu P, Liu K G. Selection of the random field mash in finite element reliability analysis[J], Journal of Engineering Mechanice, 1993, 119(4): 667-680
31. FENG Xia-ting, WANG Yong-jia. A neural network model on real-time prediction of roof pressure in coal mines[J], international Journal of Rock Mechanics and Mining Science. 1996, 33(6): 647-653