Hidrológiai Közlöny 1960 (40. évfolyam)

1. szám - Öllős Géza: Inhomogén talajok hatása a kutak vízhozamára

46 Hidrológiai • Közlöny 1960. 1. sz. öllős G.: Inhomogén talajok hatása a kutak vízhozamara KOMY HanpaBJieHino, TAN KAK npoeKTiipoBaHiie H SKCIIJIO­aTaiXHH) COOTBCTCTBGHHO BCeM TpeÖOBaHIIÍIM MOTFCHO BecTii KaK pa3 Ha OCHOBaHIIH 3HaHHü h yqeTa AeiícTBH­TenbHoro pe>KHMa <j)MJibTpaunn. Flocjie K^ACCN({)HKAMIN BOAOHOCHHX rpyHTOB c TOMKH 3peHHÍI (J)HJIbTpaUHÍI B CTaTbe PACCMATPHBAIOTCFL OCHOBHbie 3aK0HbI (J)HJTbTpaUHII no HeOAHOpOflHOMy rpyHTy, 3ATEM cJiararomne ({(HJIBTPAUHOHHOÍÍ CKOpoera [ypaBHeHiie (1)], 33KOH pa3jioMa JIHHMÍÍ TOI<a Ha rpaHime CJIOÍI [ypaBHCHHe (2)], HenpepbiBHbiií xapaicTep pacnpe­AejiemiH flaBJieHHH [ypaBHCHiie (3)]. OHJibTpanim no HE0FLH0P0/IH0MY rpyHTy MO>Ker SBITB BBIBE^EHA H3 KOS­(})imHeHTOB (JIIIJIBTPAUHH [ypaBHeHHe (4) flachler B.], ecjin (})HJibTpann>i HBJIÍICTOI aHM30TponHon, napajuiejib­HOÍÍ M NEPNCH/LHKYJIHPHOH C rpaHUMHblMIl njIOCKOCTHMIl CJioeB. HecMOTpn Ha TO, HTO STO ypaBHCHiie CTporo ro­BOpfl fleiíCTBHTejIbHO TOJlbKO FLJIH CJIOeB HeÖOJlblllOÍÍ MOm­HOCTH, BCeTaKH MO>KHO CfleJiaTb BblBOfl no HeMy H flJIH CJIYQAN KOJIOAHCB, HMCHHO, HTO xapaKTep (JiHjibTpaaHH OCTAETCH AHH30TP0NHBIM H B TOM CJiynae, ecjni JIHHHHMH TOKa NEPECEKAIOTCH rpaHiiHHbie IIJIOCKO'CTH CJioeB (0uz. 2). B flaJTbHefímeM Ha ocHOBaHHH onbiTHbix BapnaHTOB, n3o6pa>KeHHbix Ha (pueype 3., aBTopoM AaioTCíi MHCJIGH­Hbie aaHHbie AJIFL KOHTPOJIÍI 3ai<0Ha ^HJibTpauHH, nepneH­flHKyjlíipHOH (k MHH) K rpaHHHHbTM njlOCKOCTHM CJioeB (@ue. 4. H 5). MO>KHO ycTaHOBHTb, HTO ypaBHemieM (7) B ÍIEHCTBHTEJIBHOCTH XAPAKTEPM3YIOTCH IIBE30METPNHE­CKHÍI yKJIOH (Ahi), B03HHKai0mHIÍCfl B OT^ejlbHblX CJIOFLX, 3T0 KOHEHHO MO>KHO SblJIO H 0>KHflaTb : T. e. nbe30MeTpH­HecKHft yKJiOH OTflenbHbix CJioeB pacnpeAeJiíieTca ripo­nopuHOHajibHO (JiHJibTpauHOHHOMy conpoTHBjieHwo (e). XapaKmepHbie c/iynau 0uAbmpaifuu eonpyz KOAodya, uccAedoeaHHbie aBTopoM noKasaHbi Ha tpue. 6. OAHOPOAHUM rpyHTOM flaioTca OCHOBHbie aaHHbie (eapuaHm A.), aeíícTBHe CJioeB, cjiararomnxcH H3 öojiee KpvnH03epHii­CTOTO rpyHTa NOKA3BIBAETCH Ha eapuaHmax B H C, fleiícTBiie rjiHHHC TMX CJioeB noKa3aHo Ha eapuaHmax D H E, II fleííCTBIie rjlllHIICTblX J1HH3 liplIBOAHTCJl Ha eapuanme F. OnncaHiie ceKTopHon MOflejiH, ncnojib30BaHHOií HaMH, AABAJIOCB B NPEABIFLYIUNX Haunix CTATBEIÍ ]5] u [7]. Ha (pomo 1. H30§pa>KaeTcsi HOBbiií Tiin MoaejibHoro KO­JiOAHa, BBeAeHHoro aBTopoM .(ii3MepiiTejibHbiii cnocoö), c noMoinbio K0T0p0r0 MO>KHO onpeAejiHTb pecnpeAeJiemie pacxoAa II cxopocTii no BbicoTe CTÉHKIÍ KOJiOAna. Áah conocmaeAeHUH öenpeccuoHHbix Kpuebix AAETCJI oöman KapraHa HA <puz. 9. Ha Heft MO>KHO BIIAETB, HTO CTpoeHiiew rpyHTa xapaiorep AenpecciiOHHbix KPHBHX npil COCTOÍIHHH yCTaHOBIIBUierOCH ABHJKCHIIJI He H3­MEHHETCA B onwcaHHbix CJIYNAFLX. ORAOCHTEJIBHO OAHO­pOAHblX rpyHTOB HaHŐOJlbUJIie OTKJlOHeHlIÍI BbI3bIBaiOTCJI rjiHHHCTbiMH cjiOHMii (eapuaHmbi D, E, [5]). OrriHOCumeAbHO paípbiea eopu30Hma eodbi enympu cmeHKu (hb) u 6He ee (hk) aBTopoM ÖMJIO AonojiHeHo ypaB­HeHiie R. Ehrenberger sypaBHCHiie (9):, OTHOcnmeeen K opíiniHajibno OAHOPOAHBIM rpyHTaM, Ha ypaBHCHiie npii BEAEHHOE ABTOPOM (10). Kai< B STOM YPABHEHHH, TAK n B ypaBHeHiin P. Ball [ypaBHeHHe (11)] He ymiTbi­BAETCH BJIMIHHE K03(])NNHEHTA (J)iijibTpauiiH. IIpoueccpa3­pbiBa B HeoAHopoAHOM rpym'e noKa3biBaeTCH Ha <puz. 12. ÍIjih npiiöjiHweHHoro pacieTa AeSiiTa KOJiOAna Ha OCHOBaHHH KOHTpOJia KpHBblX paCXOAOB (0Ue. 13 H 14) aBTopoM peKOMeHAyeTCH ypaBHeHHe (14) B cjiyiae (Jiiijib­Tpamni aHH30TpoiiHoro xapai<Tepa. HacieT BEJIHMIIHBI KoaifiuifueHma (puAbmpaiiuu cy­mecTByioT HecKOjibKO B3rjiHA0B. B CTaTbe n0AP06H0 pac­CMOTpHBaeTCa BOnpOC, KaK Hy>KHO paCTOJlKOBaTb K03(j)H­UMCHT (JlHJIbTpaiíHH B CJiyMae HeOAHOpOAHblX rpyHTOB. B STOM CJIYMAE B 3aBHCHM0CTii OT H3MCHCHHH BHCIUHHX H BHyTpeHHHX rpaHHIHblX yCJIOBHÍÍ, AaHHblX B CHCTeMe ({)HJIbTpaUHH AJIH K03(J)HUHeHTa (})HJIbTpaUHH, MOWHO roBopiiTb TOJlbKO o BejiHHiiHe paBHOfteíScTByiomeö, npn­HaAJie>KameH K AaHHOMy COCTOHHIIIO. CTeneHb w 3aK0H0­MepHocTb H3MCHeHHH noi<a3aHbi B maŐAUife 1. K03(J)HHHeHT (jlHJlbTpaUHH nOBHAHMOMy H3MeH5ieTCH ii3-3a Toro, MTO — IOK Ha STO YKA3AJI K. YőeAA [19,20] —• BOAa H3 CBOÖOAHOÍÍ nOpllCTOCTH rpyHTa BHyTpil BOpOHKH nonaAaeT B 30Hy (JtHJibTpauin-i, T. e. B HHWCHIOIO 30Hy c 3ana3AbiBaHiieM, TOJlbKO nocjie Aenpeccim. Bo emopoü maóAuife AaeTca A0Ka3aTejibCTB0 MOfleJinpoBaHHeM H3Me­hchhíi MHHMoro KosijinuneHTa ,,K", nponcxoAamerocíi H3 3ano3AaAoro pacxoAa boaw. 3to othochtch k oahopoa­HblM rpyHTaM II K pa3HbIM M0IHH0CTHM H BOAHHblX CJioeB. HaKOHeu b CTaTbe pacciwaTpiiBaioTCH HecKOjibKO xapai<TepHbix cjiyiaeB paenpeAeAeHiiH ckopocth no bh­C0Te CTeHKH KOJTOAUa ($nr. 16, 17. w 18). B CBH3M c 3thmh (jmrypaMH aBTop CHOBa yKa3HBaeT Ha BawHOCTb yieTa Ae6nTa, nojiyHeHHoro H3 KannjuiapHOíí noAocbi, Aajiee Ha to, ito HeoAHopoAHbiMH rpym'aMH KaKoe bah­HHHe 0Ka3bIBaeTCH Ha BOAOHOCHOCTb KanilJIJlHpHblX nojioc. Tlic Effect of Inhomogeneous Soils on Well Discharge By G. Ollós Water bearing soils being in generál of inliogo­geneous stratigraphical structure, inereased efforts to extend investigations of well hydraulics in this field appear thorouglily warranted, since the proper design and correct operation of wells can be attained by appreciating and recognizing these practically en­countered percolation phenomena. Water bearing soils are classified on the basis of their percolation properties. Fundamental laws govern­ing percolation in inhomogeneous soils, velocity compo­nents of percolating flow [Eq. (1)1, the law governing discontinuities in flow filaments at boundaries be­tween two layers [Eq. (2)], and the continuity of pressure distributions [Eq. (3)] are discussed subsequently. Percolation in inhomogeneous soils—provided percola­tion is anisotropic — can be developed from percola­tion factors parallel and perpendicular to the planes bounding various layers [i?. Dachler, Eq. (4)]. Althoúgh this equation holds tone in the case of layers of small thickness, the conclusion can be arrived at therefrom alsó for the case of wells, that the character of percola­tion remains anisotropic, regardless of the fact that the paths of percolation intersect sliglitly the boundary planes (Fig. 2). Based on experiments arranged according to Fig. 3, numerical data are given (Figs. 4 and 5) for controlling the relationships governing percolation perpendicular to the boundary planes ffcmin). It can be established — as could naturally be expected —­that Eq. (7) is truly representative of. the pressure <lrop occuring over individual layers (Ahi), i. e., the pressure drop in individual layers is distributed pro­portionately to percolation resistances (e). Characteristic cases investigated by theautlior of percolation around wells are shown in Fig. 6. Funda­mental data are obtained from the liomogeneous soil (altemative A), effects of coarse-grained soils are illustrated by alternatives B and C, those of clay layers by alternatives D and E and finally those of clay lenses by altemative F. The sector model used for these experiments has been deseribed in previous papers already [5, 7], The arrangement (measuring method) of the new model well introduced by the autlior, by which the distribution of discharge and velocity along the well mantle can be determined, is shown in Fig. 1. For comparing drawdown curves a comprehensive picture is presented in Fig. 9. It will be perceived therefrom, that the shape characteristics of drawdown curves pertaining to steady conditions, are unaffected by soil structure. Related to homogeneous soil, the greatest deviation is caused. by clay layers (altemative D, E, [5]). In order to deseribe the departure of the water level within the well (hb) from the one outside (hk), the originál equation relating to homogeneous soil of R. Ehrenberger [Eq. (9)] has been modified by the author [Eq. (10)]. Neither this equation, nor that of P. Hall [Eq. (ll)j includes the effect of the percolation coef­ficient. The process of departure in inhomogeneous soil is shown in Fig. 12. For approximately computing the well discharge in the case of percolation having an anisotropic character Eq. (14) based on the checking of drawdown curves (Figs. 13 and 14) is suggested.

Next

/
  • Layout
  • Zoom
  • Rotation
Thumbnails
Contents