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<br />Landslide stabilizing options
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<br /> Stability analyses'
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<br /> Landslide
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<br /> Eagle River o 50 100 Zoo
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<br /> 11'Aii anityses assume b = 20' C1hmon 0 1s the Sireng(n at the aide material
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<br />The authors
<br />A ILL
<br />Ir t
<br />Hiller Bulvvansl.y
<br />in the central Rocky `fiwntam district ot
<br />Colorado He has 15 years' experience in
<br />pipeline Comtructwn, held utxrahon,
<br />transmission upervisicin He took his
<br />graduate study at the University or Illinois
<br />Bruce •Ntlier is employed bs western
<br />Gas Supply Co. as the operations supervisor
<br />measurement, control technology and
<br />undergraduate work in tnvlogv and chem.
<br />ictrv at 4JUthern Illinois Unwers,tv and
<br />and Colorado State Unwcrsrtv
<br />is a graduate ur T,.•chntral Unrversrty tit
<br />in civil rnginernn); aril has a Phi) in
<br />'v1u nal 8ukuvaru6v, principal of
<br />Golde• >ssaxiates, has more than 10 years'
<br />caperutnee in geo4•ChnrCal engmedrmq
<br />re+eted rv Cn•ii and mining engineering
<br />prntPCit in a,Jnnul parts or the world He
<br />Prague. Czechoslovakia. with a diploma
<br />!•ngmetru,q gcoiogv also tram Ctecho-
<br />slovalra
<br />alternatives.
<br />As the accurate course of the landslide
<br />individual stabilizing measures are
<br />-\t present, West Gas is not utliiLing
<br />strain Kauti;e5 was not removed from
<br />the old, dr_t,lched line that was left
<br />potential mitigating measures Imple-
<br />below ground. A, can he expected,
<br />no development of ?I;nil(:anl ,tram;
<br />has been noted by mrmlturlng per-
<br />foR,Jed between the nine of c\cava-
<br />tion to the end of 1980
<br />Other measures. (-);her mitlttatin,q
<br />meawres were a)n,lderc(i poor to the
<br />ahove?.;round installaUt)n It is quite
<br />possible that in the future, Wrist Gds
<br />may ChUOSe to apply "0111C Of them,
<br />Continuous development: of the
<br />landslide could finally lead West Gas
<br />to consider some of the following
<br />• Installation of the line below the
<br />landslide slip plane. The underground
<br />installation would have to be per-
<br />formed by directional drilling, rather
<br />than by installation in an open cut.
<br />Unfortunately, the cost of such an
<br />installation would be relatively high.
<br />• Stabilization of the landslide. This
<br />is technically feasible because the
<br />landslide yardage is fairly limited.
<br />Stabilization could be performed by
<br />dewatering of the landslide. an exca-
<br />vation of the landslide's upper por-
<br />tion, or construction of a toe buttress.
<br />These alternatives were studied and
<br />analyzed as shown on Fig. 6.
<br />The stability analyses are based an
<br />the assumption that the present ractor
<br />of safety of the landslide is equal to i.
<br />slip plane and groundwater conditions
<br />are not known, these assumptions are
<br />only very approximate.
<br />Increases of factors of safety with
<br />shown on Fig- b. It appears that the
<br />most effective method of landslide
<br />stabilization is dewaterint;.
<br />any of these mitigating measures. The
<br />area in the vicinity of Landslide ' will
<br />he closely monitored in the future and
<br />mented only after loot;-term evalua-
<br />tion of the area's behavior.
<br />References
<br />\r'rrvr lendsLde,, ' r rvicerYlmgs of ;he Internr
<br />or w,sivnsm. Madison. Aug 2' 7-29 1985
<br />I !i„??wanshv, 1A (;rrernvrxxl, I N md waprr
<br />, 'bldin(Jinnlg A N,tlur.ll t;at 11,i><'I n,e ?n
<br />turn,d Conference Advances :n Clndergrnuror
<br />P:vs•ime Engineering. PC Div . ASCE. l,'mvrail,
<br />C;+ce•nwosxi, I H , Buhovanskv M ,and 'vlalnr
<br />1, 'zinc-Munitvnnq instrurnrnts prove elkt -
<br />riar• ror western US .urns wblect to land-
<br />.lules," OGI. Feb IT• 11)86, pp nd•-1
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