水利專業(yè)混凝土重力壩中英文對照外文翻譯文獻

1、 中英文資料外文翻譯混凝土重力壩基礎流體力學行為分析摘要：一個在新的和現(xiàn)有的混凝土重力壩的滑動穩(wěn)定性評價的關鍵要求是對孔隙壓力和基礎關節(jié)和剪切強度不連續(xù)分布的預測。本文列出評價建立在巖石節(jié)理上的混凝土重力壩流體力學行為的方法。該方法包括通過水庫典型周期建立一個觀察大壩行為的數(shù)據(jù)庫，并用離散元法（DEM）數(shù)值模式模擬該行為。一旦模型進行驗證，包括巖性主要參數(shù)的變化，地應力，和聯(lián)合幾何共同的特點都要納入分析。斯威土地，Albigna大壩坐落在花崗巖上，進行了一個典型的水庫周期的特定地點的模擬，來評估巖基上的水流體系的性質(zhì)和評價滑動面相對于其他大壩巖界面的發(fā)展的潛力。目前大壩基礎內(nèi)的各種不同幾何的巖

2、石的滑動因素，是用德國馬克也評價模型與常規(guī)的分析方法的。裂紋擴展模式和相應揚壓力和抗滑安全系數(shù)的估計沿壩巖接口與數(shù)字高程模型進行了比較得出，由目前在工程實踐中使用的簡化程序。結(jié)果發(fā)現(xiàn)，在巖石節(jié)理，估計裂縫發(fā)展后的基礎隆起從目前所得到的設計準則過于保守以及導致的安全性過低，不符合觀察到的行為因素。關鍵詞：流體力學，巖石節(jié)理，流量，水庫設計。簡介：評估抗滑混凝土重力壩的安全要求的理解是，巖基和他們上面的結(jié)構(gòu)是一個互動的系統(tǒng)，其行為是通過具體的材料和巖石基礎的力學性能和液壓控制。大約一個世紀前，Boozy 大壩的失敗提示工程師開始考慮由內(nèi)部產(chǎn)生滲漏大壩壩基系統(tǒng)的揚壓力的影響，并探討如何盡量減少其影響

3、。今天，隨著現(xiàn)代計算資源和更多的先例，確定沿斷面孔隙壓力分布，以及評估相關的壓力和評估安全系數(shù)仍然是最具挑戰(zhàn)性的。我們認為，觀察和監(jiān)測以及映射對大型水壩的行為和充分的儀表可以是我們更好地理解在混凝土重力壩基礎上的縫張開度，裂紋擴展，和孔隙壓力的發(fā)展。圖.1 流體力學行為：（一）機械;（二）液壓。 本文介紹了在過去 20 個來自 Albigna 大壩，瑞士，多年收集的水庫運行周期行為的代表的監(jiān)測數(shù)據(jù)，描述了一系列的數(shù)值分析結(jié)果及評估了其基礎流體力學行為。比較了數(shù)值模擬和實際行為在實地的監(jiān)測結(jié)果。在此基礎上比較了一系列的結(jié)論得出了基本孔隙壓力在節(jié)理巖體的影響可以考慮在其他工程項目，認為那里的巖石節(jié)

4、理流體力學行為應予以考慮。這些項目包括壓力管道，危險廢物處置，以及對流動行為的控制斷面沿巖石地質(zhì)遏制依賴的其他情形。nnKni KKVniKniana行為，i. e，兩者在液壓機械孔徑由于孔徑的變化變化的關系，鑒于a其中 是剩余的水力孔徑hr因此，用經(jīng)典的立方定律表示通過巖石節(jié)理流率：h是沿巖石節(jié)理頭部下降;是水（11.005wa 流地下 G=W/L（其中 W 和 L 是寬度和長度，分別聯(lián)合），為不同徑向流，G =2/ln(re)/,另外，巖體等效滲透，公里，可以以同樣的形式作為修改后的定律，或在液壓口徑計算，同樣的形式占關節(jié)間距，S:在裂隙巖體滲透性的變化，由于覆蓋層和圍應力，計算。 1 -

5、 3。巖體的滲透性，K，理論的深度關系的結(jié)果高達 1000 米，采用當量。 5載于圖 2?？椎囊簤弘SVakmchoni在深露天礦在巴西花崗巖開采項目獲得的場滲透率測量在圖 2 中繪制與理論的關系比較。聯(lián)合間距從鉆孔巖心觀察值都在數(shù)米范圍內(nèi)，從而產(chǎn)生了一個 5 米間距是常數(shù)的計算假設。阿霍的價值在 300 -1000m 范圍被用來確定公里= f 的理論關系（z）的，其中 Z 是深度，以實地測量和比較這兩個鉆孔測量值相對滲透率在 100 至 200 米深處的高，可能表明的一個區(qū)或剪切節(jié)理巖帶更多的存在。所測巖石滲透率穩(wěn)步下降，在深度的增加，然而，它們的值與對應的巖體滲透性的理論與模型估計趨勢良好。

6、K典型液壓孔徑 400 -500m 的和后關節(jié)僵硬=10V 的雙曲線關系，與三菱商Va似乎同意這些結(jié)晶巖體觀測場行為良好。ho Hydromechanical analysis of flow behavior in concrete gravity damfoundationsAbstract: A key requirement in the evaluation of sliding stability of new and existingconcrete gravity dams is the prediction of the distribution of pore pressu

7、re and shearstrength in foundation joints and discontinuities. This paper presents a methodology forevaluating the hydromechanical behavior of concrete gravity dams founded on jointed rock.The methodology consisted of creating a database of observed dam behavior throughouttypical cycles of reservoir

8、 filling and simulating this behavior with a distinct elementmethod (DEM) numerical model. Once the model is validated, variations of keyparameters including litho logy, in situ stress, joint geometry, and joint characteristics canbe incorporated in the analysis. A site-specific simulation of a typi

9、cal reservoir cycle wascarried out for Albigna Dam, Switzer land, founded on granitic rock, to assess the nature ofthe flow regime in the rock foundations and to evaluate the potential for sliding surfacesother than the damrock interface to develop. The factor of safety against sliding of variousroc

10、k wedges of differing geometry present within the dam foundations was also evaluatedusing the DEM model and conventional analytical procedures. Estimates of crackpropagation patterns and corresponding uplift pressures and factors of safety againstsliding along the damrock interface obtained with the

11、 DEM were also compared withthose from simplified procedures currently used in engineering practice. It was found thatin a jointed rock, foundation uplift estimates after crack development obtained frompresent design guidelines can be too conservative and result in factors of safety that are toolow

12、and do not correspond to the observed behavior.Key words: Hydromechanical, jointed rock, flow, dam design.Introduction: Evaluating the safety of concrete gravity dams against sliding requiresan understanding that rock foundations and the structure above them are an interactivesystem whose behavior i

13、s controlled by the mechanical and hydraulic properties ofconcrete materials and rock foundations. About a century ago, the failure of Boozy Damprompted dam engineers to start considering the effect of uplift pressures generated by This paper presents behavior representative of cycles of reservoir o

14、peration in the last20 years collected from monitored data of Albigna Dam, Switzerland, and also describesthe results of a series of numerical analyses carried out to assess the hydromechanicalbehavior of its foundations. Comparisons are made between results of numerical modelingand the actual behav

15、ior monitored in the field. Based on these comparisons, a series ofconclusions are drawn regarding basic pore-pressure buildup mechanisms in jointed rockmasses with implications that may be considered in other engineering projects, where thehydromechanical behavior of jointed rock should be consider

16、ed. Such projects include pressure tunnels, hazardous waste disposal, and other situations dependent on geologiccontainment controlled by flow behavior along rock discontinuities.Hydromechanical behavior of natural jointsnnThe magnitude of the closure per unit of stress decreases rapidly, however, a

17、s the stressKlevel increases. The hyperbola is defined by the initial tangent stiffness, , and theniV. This relationship is also nonlinear and hystereticKVFor natural and induced fractures in granite, these parameters are interrelated and rangebetween the following limits Alvarez et al. (1995):KVis

18、in mmcRough joints exhibit the largest joint maximum closure and the lowest initial jointVKstiffness, whereas smooth joints have the lowestand the largestmcniThe hydraulic behavior of the rock joint is characterized by the linear relationship abetween hydraulic aperture, , which controls the magnitu

19、de of flow, and mechanical jointhclosure, which depends on stress levels. Hydraulic apertures are plotted versus theirnacorresponding joint closure (Fig.1b)to obtain the line intercept,initial hydraulichofaperture, and the coupled slope coefficient, ,which characterizes the hydromechanicalbehavior o

20、f the joint ,i. e., the relationship between changes in hydraulic aperture due tochanges in mechanical aperture, given byahrhWhere Q is the flow rate;wajoint hydraulic aperture; and G is the shape factor, which depends on the geometry of flow.For straight flow, G=W/L (where W and L are the width and

21、 length, respectively, of therjoint); and for divergent radial flow, G=2/ln (re/ ), whereand re are the borehole andiexternal cylindrical surface radiuses, respectively.Jointed rock mass permeability change with depthAlternatively, the rock mass equivalent permeability, km, can be expressed in thesa

22、me form as the modified cubic law, or in terms of hydraulic aperture, to account forspacing of the joints, S: permeability that decreases with an increase in depth fromVaThe rock mass permeability estimates were obtained assuming f=1.0,=mckniout in granitic formations(Alvarez et al.1995)similar to t

23、hose of the Brazilian test locationdescribed in this section. Overburden stresses were estimated using a unit weight of 26.0kN/m3.In this case it was assumed that horizontal and vertical stresses are about the same(coefficient of earth pressure at rest Ko=1.0), which are also considered to bereprese

24、ntative of the igneous formations at the Brazil test location, but other values of insitu stresses could be estimated, e.g., for Ko1.0, vertical joints would have largerpermeabilities.Field permeability measurements obtained in Packer tests at a deep open-pit miningproject in granitic rock in Brazil are also plotted in Fig.2 for comparison with thetheoretical relationship. Values of joint spacing observed from borehole cores are in therange of a few meters, and thus a constant spacing of 5m was assumed in the computations.Values of aho in the range of 3001000m were