Effect of Uplift Pressure under Hydraulic Structure Founded

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1 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April Effect of Uplift Pressure uner yraulic Structure Foune on an Anisotropic Soil Aseel A. A. AlKati Faculty of Engineering,University of Kufa aier A. A. AlKati Faculty of Engineering,University of Kufa ayer. Alkhuery Faculty of Engineering,University of Kufa ABSRAC: In this research, Slie program was use to analyze seepage flow uner the hyraulic structure through isotropic an anisotropic soils an its effect on structures with cutoff at ownstream, at upstream, an at oth of them. he istriution curves of uplift pressure along the floor ha een reache at ownstream for ifferent egrees of anisotropy from the horizontal ais. he effects of anisotropy on uplift pressure. he analysis process epens on a finite element metho. Eightnoe quaratic elements to represent the porous meia. he maimum values of uplift pressure uner the structure with cutoff at ownstream are seen at, an inclination angles an the minimum values are seen at inclination angle, the maimum values of uplift pressure uner the structure with cutoff at upstream are at inclination angle an the minimum values are at, an angles, an the maimum values of uplift pressure uner the structure with cutoff at upstream an ownstream are at inclination angle an the minimum values are at, an inclination angles ut the relationship is reverse after =.. he quantity of seepage in ownstream sie of the structure with a cutoff at ownstream was. m /ay, at upstream was. m /ay, an at oth of them was. m /ay. he quantity of seepage for anisotropic soils was calculate for all cases. KEYWORDS:pressure hea,uplift pressure, seepage, isotropic soil an anisotropic soil.. INRODUCION: yraulic structures asconcrete ams, weirs,culvert, gates, retaining walls etc. are foune on impervious soil or pervious soil. he ifference in water level etween upstream an ownstream through the hyraulic structure results in water seepage through the soil uner the hyraulic structure. anothermethoscalculationslike mathematical solutions, electrical solutions, flow moels, fragments methos, an numerical methos [].. SEEPAGE ANALYSIS: he effect of seepage through soil requires calculation of uplift pressure uner the structure. he uplift pressure is one of the important points that are consier to the safety an staility of hyraulic structures. It refers to the pressure of the water seepage uner the structure that pushes the floor to up irection. he piping cavities are een ue to water seepage across salt soil (e.g. gypsum salts). these cavities ue to salts that weaken the soil of the hyraulic structure founation. he isotropic soil, the values of hyraulic conuctivity are equal in all irections. In anisotropic soil, they not equal with ifferent in irection. In this research, the effect of anisotropy of soil uner the hyraulic structures with sheet pile at ownstream, at upstream, an at oth of them on the uplift pressure are stuie. he flow across a saturate soil is given y Darcy's law: K i () Where: V s V s = Velocity through porous meia Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

2 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April K = yraulic conuctivity h i = yraulic graient = l h = Piezometric hea l = Distance along the flow line Darcy's law is vali when Reynols numer is taken equal to or less than unity, or Where Re = Reynols numer. V = Discharge velocity. D = Average of iameter of soil particles. = Density of flui, an = Dynamic viscosity VD Re Fortunately, most of practical seepage flow uner am is laminar (Re ) []. (). E ANISOROPY SOIL AND ISOROPY: If an y coorinates is the coorinate Direction, the hyraulic conuctivity values in the irections is specifie as K, an Ky, another point or any point(, y) an isotropic caseis K = Ky, an anisotropic caseisk Ky.. E YDRAULIC CONDUCIVIY: he conuctivity in the two imensional cases Is in the maimum an minimum values along the aes, are principal ais. Other irections through the omain of hyraulic conuctivity are etween the principal values are given[] with the principal values making the major an minor ais. the flow uner hyraulic structures at anisotropic soil founation, where the flow is in the (, y) coorinate aes makes an angle β with the principal aes of conuctivity of the soil, the coorinate system points(µ, λ) is consier the principal aes of hyraulic conuctivity,hyraulic conuctivity an ais rotationis shown in figure (). Y µ k min k ma Fig.() yraulic conuctivity an ais rotation,[]. Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

3 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April. EQUAION OF FLOW: he analysis of the seepage velocity through soilin the law of Darcy for woimensional flow are []: u k () v k y () y where: u, v = Velocity components in the horizontal irection, anvertical y irection. k, k y= yraulic conuctivity in the an y irections. he continuity equation for twoimensional of flow is following: u v y Sustitute the law of Darcy, eq.(), in eq.() gets the following: k k y y y () () For a homogenous an isotropic soil, the hyraulic conuctivity is equal in all the irections, is: k = k y = k hus, eq.() is: y he continuity equation for seepage flow in anisotropic soil is[]: Where: q y q y q, an q y are seepage flues in an y irection respectively an are given in equation (). () (). SLIDE PROGRAM: Slie V.. is a finite element ase analysis of seepage, for saturate/unsaturate, steay flow conitions,the seepage analysis y slieis shown in figure (). Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

4 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April Start program A eternal ounary A material ounary Assignmaterial ounary Define material properties Moe of analysis Groun water RuCoefficie Water surface Finite element metho Mesh setting Refine mesh Define material ounary Compute Interpret Show the results Fig. () he seepage analysis y slie program []. Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

Geometry parameters ( ifference of soil, location of cutoff).. Physical parameters ( change in egree of anisotropy).

5 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April. YDRAULIC SRUCURE WI CUOFF A DOWNSREAM: he effect of parametric on the uplift pressure uner hyraulic structure, are ivie like the following:. Geometry parameters ( ifference of soil, location of cutoff).. Physical parameters ( change in egree of anisotropy). Quantity of seepage in ownstream sie for isotropic soil an flow vector is shown in figure (),an the imension of the prolemis shown in figure(). Fig.():Flow lines with ownstream sie for.m /ay isotropic soil founation. Fig. () Quantity of seepage in ownstream sie for isotropic soil an flow vector. m X X. Fig.() Dimension of the prolem Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April INCLINAION ANGLEEFFEC AND DEGREE OF ANISOROPY SOIL: he istriution of uplift pressure uner the

6 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April INCLINAION ANGLEEFFEC AND DEGREE OF ANISOROPY SOIL: he istriution of uplift pressure uner the retaining structure for ifferent anisotropic angles at ifferent inclination angles (,,, an ) are shown in Figures(),(),(),an() respectively. It has een foun that at angle, the istriution of uplift pressure increase with increasing the egree of anisotropy. In regar to the an angles, the values of uplift pressure ecrease with increase in egree of anisotropy. In contrast, the istriution of uplift pressure for angle increase with increasing permeaility until / =., then ecrease with increasing permeaility. Pressure hea Distance along floor ase (/) kma / kmin= kma / kmin= kma / kmin= kma / kmin= Pressure hea Distance along floor ase (/) kma / kmin= kma / kmin= kma / kmin= kma / kmin= Fig.() Uplift pressure istriution uner hyraulic structure with D/S cutoff in anisotropic soil at (Ө=). Pressure hea kma / kmin= kma / kmin= kma / kmin= kma / kmin= Distance along floor ase (/) Fig.() Uplift pressure istriution uner hyraulic structure with D/S cutoff in anisotropic soil at (Ө=). Fig.() Uplift pressure istriution uner hyraulic structure with D/S cutoff in anisotropic soil at (Ө=). Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery Pressure hea kma / kmin= kma / kmin= kma / kmin= kma / kmin= Distance along floor ace (/) Fig.() Uplift pressure istriution uner hyraulic structure with D/S cutoff in anisotropic soil at (Ө=).

7 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April he istriution of uplift pressure uner the hyraulic structure for ifferent inclination angles an ifferent egrees of anisotropy (, an ) are shown in Figures(),an ( ) respectively. It can e seen from these figures, that the istriution values of uplift pressure are maimum at,an egree angles which are greater than the values of uplift pressure for isotropic soil. his is attriute to the relatively large hyraulic conuctivity causing increase in uplift pressure. It is also notice that the values of uplift pressure were minimum at angle. his is ue to the fact that the hyraulic conuctivity is small along the floor which cause large hea losses in that irection.he uplift pressure values of angle are greater than the uplift pressure values of angle, as the stream lines are incline more towar the structure floor when the angle is causing greater values for uplift pressure. Likewise, an have the same effect. q = q = q = q = q = q = q = q = q = q = q = q = Pressure hea Pressure hea Distance along floor ase (/) Distance along floor ase (/) Fig.() Uplift pressure istriution uner hyraulic structure with D/S cutoff in anisotropic soil at (kma/kmin=). Fig.() Uplift pressure istriution uner hyraulic structure with D/S cutoff in anisotropic soil at (kma/kmin=). EFFEC OF LOCAION OF CUOFF ON UPLIF PRESSURE: Figure() illustrates the istriution of uplift pressure uner the floor ase of the hyraulic structure for ifferent locations of the cutoff. When the cutoff is at upstream, uplift pressure ecreases ue to increasing hea loss from increasing length of creep whenever the cutoff is far away from upstream, uplift pressure values increase. Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April he cutoff at U/S he cutoff at. he cutoff at. he cutoff at. Pressure hea he cutoff at.

() Uplift pressure istriution uner hyraulic structure with various locations of cutoff in isotropic soil ale() Results of Quantity of Seepage (m³/s/m) for Different kma/kmin an Constant

8 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April he cutoff at U/S he cutoff at. he cutoff at. he cutoff at. Pressure hea he cutoff at Distance along floor ase (/) Fig.() Uplift pressure istriution uner hyraulic structure with various locations of cutoff in isotropic soil ale() Results of Quantity of Seepage (m³/s/m) for Different kma/kmin an Constant Valueof Inclination Angle for (,,, ) kma/kmin θ.e.e.e.e.e.e.e.e.e.e.e.e.e.e.e.e. REAINING SRUCURE WI CUOFF A UPSREAM he quantity of seepage for hyraulic structures with cutoff at upstream as shown in figure().m /ay Fig. () Quantity of seepage in ownstream sie for isotropic soil an flow vector. Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

9 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April he istriution of uplift pressure for retaining structure for ifferent egrees of anisotropy an ifferent inclination angles (,,, an ) are shown infigures (), (), (), an () respectively. It is foun that for angle, the istriution values of uplift pressure ecrease with increasing anisotropy from those of isotropic soil.it is foun that the uplift pressure values for the angles (,, an ) increase when the anisotropy increases. his eplaine the fact that stream lines move in the irection of the structure floor as the anisotropy increases causing greater values of the uplift pressure. kma / kmin= kma / kmin= kma / kmin= kma / kmin= kma / kmin= kma / kmin= kma / kmin= kma / kmin= Pressure hea Pressure hea Distance along floor ase (/) Distance along floor ase (/) Fig. () Uplift pressure istriution uner hyraulic structure with U/S cutoff in anisotropic soil at (Ө=) Fig. () Uplift pressure istriution uner hyraulic structure with U/S cutoff in anisotropic soil at (Ө=) Pressure hea kma / kmin= kma / kmin= kma / kmin= kma / kmin= Distance along floor ase (/) Fig. () Uplift pressure istriution uner hyraulic structure with U/S cutoff in anisotropic soil at (Ө=) Pressure hea kma / kmin= kma / kmin= kma / kmin= kma / kmin= Distance along floor ase (/) Fig. () Uplift pressure istriution uner hyraulic structure with U/S cutoff in anisotropic soil at (Ө=) Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

10 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April Figures()an ( ) illustrate the istriution of uplift pressure uner the structure for ifferent inclination angles anfor two ifferent egrees of anisotropy (, an ) respectively. It can e seen that the values of uplift pressure for angle is lower than uplift pressure values of isotropic soil, since the hyraulic conuctivity will e smaller along the cutoff causing major reuction in hea lossesof that irection.for angle, the uplift pressure values will e maimum an so greater than the uplift pressure values of isotropic soil, ecause conuctivity is greater in the irection of the cutoff causing minor reuction in hea losses in that irection an consequently high values of uplift pressure.it is realize that the values of uplift pressure for angles less than angle will e greater than the values of uplift pressure for isotropic soil. his is ue to the stream lines which approach towar the structure floor causing increase in the uplift pressure values. Pressure hea Distance along floor ase (/) q = q = q = q = q = q = Pressure hea q = q = q = q = q = q = Distance along floor ase (/) Fig. () Uplift pressure istriution unerhyraulicstructure with U/S cutoff in anisotropic soil at (kma/kmin=). Fig.() Uplift pressure istriution uner hyraulic structure with U/S cutoff in anisotropic soil at (kma/kmin=). ale() Results of Quantity of Seepage (m³/s/m) for Different kma/kmin an Constant Value of Inclination Angle for (,,, ) kma/kmin θ.e.e.e.e.e.e.e.e.e.e.e.e.e.e.e.e Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April. REAINING SRUCURE WI CUOFFS A UPSREAM AND DOWNSREAM he quantity of seepage is.m is shown in figure().

he istriution of uplift pressure uner the retaining structure with upstream an ownstream cutoffs for ifferent egrees of anisotropy an ifferent inclination angles (,,, an ) are shown in

11 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April. REAINING SRUCURE WI CUOFFS A UPSREAM AND DOWNSREAM he quantity of seepage is.m is shown in figure().m /ay Fig. () Quantity of seepage in ownstream sie for isotropic soil an flow vector. he istriution of uplift pressure uner the retaining structure with upstream an ownstream cutoffs for ifferent egrees of anisotropy an ifferent inclination angles (,,, an ) are shown in Figures(),(),(),an() respectively. It is foun that the istriution curves of the uplift pressure meet in one point ecause of the comine effect of the cutoffs that change the physical characteristics of the flow through the porous meium. he meeting point is changing from one case to another epening on the value of the inclination angle an the egree of anisotropy.it can e seen from figure () that at angle, the meeting point will e when / =., an the istriution of uplift pressure efore the meeting point ecrease with increasing anisotropy. In contrast, they increase with increasing anisotropy after the meeting point.figure () illustrates that at angle, the meeting point will e happene when / =., an the istriution of uplift pressure efore the meeting point increase an after the meeting point ecreases with increasing egree of anisotropy.figure () shows that at angle, the meeting point will e occure when / =.. he values of uplift pressure efore the meeting point increase with increasing egree of anisotropy, while after the meeting point the uplift pressure values ecrease with increasing of anisotropy.figure () shows that when the inclination angle is, the meeting point will e at / =.. he values of uplift pressure increase efore the meeting point an thereafter ecrease. Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

12 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April Pressure hea kma / kmin= kma / kmin= kma / kmin= kma / kmin= Pressure hea kma / kmin= kma / kmin= kma / kmin= kma / kmin= Distance along floor ase (/) Distance along floor ase (/) Fig. () Uplift pressure istriution uner hyraulic structure with U/D cutoffs in anisotropic soil at (Ө=). Fig. () Uplift pressure istriution uner hyraulic structure with U/D cutoffs in anisotropic soil at (Ө=). kma / kmin= kma / kmin= kma / kmin= kma / kmin= kma / kmin= kma / kmin= kma / kmin= kma / kmin= Pressure hea Pressure hea Distance along floor ase (/) Distance along floor ase (/) Fig. () Uplift pressure istriution uner Fig.() Uplift pressure istriution uner hyraulic structure with U/D hyraulic structure with U/D cutoffs in anisotropic soil at cutoffs in anisotropic soil at (Ө=). (Ө=). Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

13 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April Figures(),an () illustrate the istriution of uplift pressure uner the hyraulic structure with cutoff at upstream an ownstream for ifferent inclination angles anfor ifferent egrees of anisotropy (, an ) respectively.it can e seen that at angle, the uplift pressure values are smaller than those of isotropic soil till / =., thereafter they are greater. In contrast, at angle, the values are greater than those of isotropic soil till / =., thereafter smaller.he values of uplift pressure at angle are a little it higher than those of isotropic soil, while those at angle are greater than those of isotropic soil an those seen in angle. he same thing is notice in an angles. q = q = q = q = Pressure hea q = q = q = q = Pressure hea q = q = q = q = Distance along floor ase (/) Distance along floor ase (/) Fig. () Uplift pressure istriution uner hyraulic structure with U/D cutoffs in anisotropic soil at (kma/kmin=). Fig. () Uplift pressure istriution uner hyraulic structure with U/D cutoffs in anisotropic soil at (kma/kmin=). EFFEC OF DEP OF CUOFFS ON UPLIF PRESSURE: he effect of epth is changing in cutoff at upstream from epth in cutoff at ownstream on uplift pressurewhichis shown infigures().it can e seen that when the epth of cutoff at upstream is greater than that at ownstream. ale() Results of Quantity of Seepage (m³/s/m) for Different kma/kmin an Constant Value of Inclination Angle for (,,, ). kma/kmin θ.e.e.e.e.e.e.e.e.e.e.e.e.e.e.e.e Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

14 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April.CONCLUSIONS: he following conclusions are reache at the en of this stuy:. he values of uplift pressure uner structure with cutoff at ownstream at, an angles will e a maimum an greater than those of isotropic soil. In contrast, they are minimum at angle, an they are smaller than those of isotropic soil.. he maimum istriution of uplift pressure uner the structure with cutoff at upstream will e at angle, an they are greater than those of isotropic soil. he smallest values are seen at angle, however they are smaller than those of isotropic soil. / =. / =. / = / = Pressure hea Distance along floor ase (/) Fig. () Uplift pressure istriution uner retaining structure withu/d cutoffs in isotropic soil for various /. he values of uplift pressure uner the structure with cutoff at ownstream at angle increase y increasing anisotropy, while at, an angles, they ecrease y increasing anisotropy. In contrast, they increase y increasing anisotropy till / =., thereafter ecrease in case of angle.. he values of uplift pressure uner the structure with cutoff at upstream at, an angles ecrease y increasing anisotropy, while they increase in other angles.. he istriution of uplift pressure for the structure with cutoffs at upstream an ownstream meet in one point an the position of this point epens on the egree of anisotropy an the inclination angle at, an angle, the values of uplift pressure efore the meeting point ecrease y increasing anisotropy while after the meeting point, the increase y increasing anisotropy. In regars to the other angles, the values of uplift pressure efore the meeting point increase y increasing anisotropy, an thereafter ecrease will happen y increasing anisotropy.. he istriution of uplift pressure uner the structure with cutoffs at upstream an ownstream will e minimum at, an angles. he values are smaller than those of isotropic soil efore the meeting point, an greater after the meeting point. he maimum values will e at angle, an these efore the meeting point are greater than those of uplift pressure for isotropic soil, while after the meeting point, they are smaller than those of isotropic soil. Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

15 International Journal of Engineering echnology Science an Research IJESR ISSN Volume, Issue April REFERENCES []Arao, F.,, Soil Mechanices an Founation Engineering, Vol., Aleanria University, Pulishe y rate Beirut. []Freeze, R. A., an Cherry, A.,, Groun Water, Prenticeill, Englewoo Cliffs. U.S.A. []arr, M. E.,, Groun Water an Seepage, Mc Grawill Book Company. []olts, R. D., an Kovacs, W. D.,, An Introuction to Geotechnical Engineering, Prenticeill, Inc. Newyersey. []AlSaai, S. I.,, Numerical Analysis of Seepage Prolems with Flow Control Devices Unerneath yraulic Structures, Ph.D. hesis in Water Resources Engineering, University of echnology. []Alurrfy, U. A.,, Staility Analysis of Earth Dams: aitha Dam As A Case Stuy, Ms.c.. hesis in civil Engineering, University of Baylon. Aseel A. A. AlKati, aier A. A. AlKati, ayer. Alkhuery

APPROXIMATE SOLUTION FOR TRANSIENT HEAT TRANSFER IN STATIC TURBULENT HE II. B. Baudouy. CEA/Saclay, DSM/DAPNIA/STCM Gif-sur-Yvette Cedex, France

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