An Effective Stress Analysis of Unsaturated Slope Failures by Rainfall Infiltration

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ISSN 1229-2427 (Print) ISSN 2288-646X (Online) http://dx.doi.org/10.7843/kgs.2013.29.12.77 㻤ᛵ㍈■ᙽ㻡䀔ᬄⓀ㍙# # ㆤ29᜔# 12㿀# 2013ᫌ# 12ぜ# pp. 77 G 85

JOURNAL OF THE KOREAN GEOTECHNICAL SOCIETY Vol.29, No.12, December 2013 pp. 77 G 85

འ⧻# ㆳ㕷ᮧ# ⫃㢧# ⃓㜷㦟# ⏷ᶿ# ⃠ၿ⪣# ⩫㧳⪜᭰# 㢿⑨

An Effective Stress Analysis of Unsaturated Slope Failures by Rainfall Infiltration

㇫へ䆏¹ Lee, Young-Huy ゛ ⮯ ⠌² Oh, Se-Boong 㐻㇯㜗³ Jin, In-Chul ᢷ ㍷ㄧ⁴ Kim, Jun-Woo

⚌ へ ┠¹Park, Yeong-Mog

Abstract

Unsaturated slopes experience infiltration during rainfall and become unstable when saturated. On the viewpoint of unsaturated effective stress, as matric suction decreases, both effective stress and shear strength decrease, which declines slope stability consequently. This study is focused on describing effective stress based on suction stress. The actual slope failures are simulated to calculate factors of safety in the field of finite element stress. In the residual soils of Hadong and Pohang, unsaturated properties are evaluated by laboratory tests. For unsaturated slopes, analyses of infiltration, stress and stability were performed to simulate actual failures. Based on unsaturated effective stress principle, the stability of actual slopes could be evaluated successfully. It is verified for the effective stress concept to be applicable to the engineering practice on slope design which considers infiltration by rainfall.

⧟# # # ⴋ

ҝपজԐϸقԴəÌڍ֨ࠞ࣊ÀێرǣČपজÀʿق˰͆ҝ؋܁३ݕɰ. ҝपজࢹۆڮমڿͳۆě۾قԴə, Ͽěড়սͳۋÇՙॠϸڮমڿͳۋÇՙॠČʴ֨قۻɳÌʪʪÇՙॠيԐϸ؋܁Ձۋ۹३ʽɰ. ٍ҆ĵقԴə

ҝपজࢹۆڮমڿͳںড়սڿͳڷͿşցॠəʚߣ۾ں˅ɰ. ŔνČڮॢڅՙڿͳۤقԴ؋ۻڱںćԓॠي֬܃

ԐϸۆңĨε֨бͪۋՎॢɰ. ॠʴфप२ݓًۆॄজࢹݓࠗقʂॠي֬Ǵ֬ॹںսॱॠيҝपজНՁںқԵ ॠٕɰ. ŔνČҝपজԐϸۆࠞ࣊३ԵںսॱॠČڿͳ३Եę؋܁३Եںࣀॠي֬܃ңĨεۦইॠٕɰ. ˰͆Դ

ҝपজڮমڿͳڙνقŖäॠي, ֬܃Ԑϸۆ؋܁ՁںՁėۺڷͿथÀॣսەؽɰ. ڮমڿͳÒȝۋÌڍࠞ࣊ε

ČͲॢԐϸԺćۆ֬Иقۺڌʾսەڼںۓݒॠٕɰ.

Keywords : Effective stress, Suction stress, Rainfall infiltration, Slope stability, Unsaturated soils

1ⲯ㬦⭪, ⪛ᕂរ㧳ᇪ# ᄎ▾❶✾㗶ᆏ㧳ᆖ# ᇪ⚲# (Member, Prof., Dept. of Civil Engrg., Yeungnam Univ.)

2ⲯ㬦⭪, ⪛ᕂរ㧳ᇪ#ᄎ▾❶✾㗶ᆏ㧳ᆖ#ᇪ⚲#(Member, Prof., Dept. of Civil Engrg., Yeungnam Univ., Tel: +82-53-810-3512, Fax: +82-53-810-4622, [email protected], Corresponding author, ᇪ❺ⲚⰪ)

3⋞㬦⭪, ⪛ᕂរ㧳ᇪ# ᄎ▾❶✾㗶ᆏ㧳ᆖ# ▷╆# (MSc, Dept. of Civil Engrg., Yeungnam Univ.) 4⋞㬦⭪, ᄎⰖ⩮⹚ᝢ⩎ṛ# ╆⭪# (Kunil Engrg.)

*→# ᘖῒ⩪# រ㧶# 㘺⯲Ḗ# ⭪㧲ᜮ# 㬦⭪⯚# 2014ᗞ# 6⭮# 30Ⱆዦ⹚# ኒ# ᕎ⭃⯞# 㧳㬦ᳶ# ↎ᕎⶖ❶ዊ# ₮ᰧᝢ᝾. ⲚⰪ⯲# ᄚ㘺# ᕎ⭃ᆖ# 㨂፲# ᘖῒ⹫⩪# ᄦⱆ㧲⪆# ᥶ṗᝢ᝾.

This is an Open-Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License (http://creativecommons.org/licenses/by-nc/3.0) which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.

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1. ⑧# ᮫

TerzaghiۆڮমڿͳÀԺߌͤ, Bishop(1954, 1959)ق

ۆॢҝपজࢹۆڮমڿͳڷͿҝपজݓъۆėॡۺ

Л܃εԺϼॣսەɰ. Ŕ͠ǣBishop ڮমڿͳڹ֬ڌ ۺڷͿۺڌॠşÀTerzaghiۆڮমڿͳ҃ɰϔڍūɰ

΄ɰ. Luٮٍĵۙ˞(Lu and Likos 2006; Lu et al. 2010, Oh et al. 2012)ڹড়սڿͳ(suction stress)ں܃؋ॠي

Bishop ڮমڿͳںێъজॠٕɰ. ড়սڿͳڹϿěড়ս ͳۋڮমڿͳقşيॠə܁ʪε܁͟ۺڷͿशইॢ

ɰ. ҝपজࢹۆۻɳÌʪəսνۺ࣢Ձęٍěۋەر Դ, ড়սڿͳڹ॥ս࣢ՁčԸ(soil water retention curve, SWRC)ڷͿҙࢢĵॣսەɰ. Lu et al.(2010)ڹড়սڿ ͳقʂॢ॥սεڮʪॠٕڷ϶, van Genuchten(1980) ۆ॥ս࣢ՁčԸںۋڌॠيĵॣսەɰ. ۋ͠ॢڮম ڿͳںۺڌॠϸ, ҝपজࢹۆۻɳÌʪəपজʪقИ ěॠóڮێॠó܁ۆʽɰ.

æԺėԐҼ࢐ϸԺćşܵ(Korea Infrastructure Safety Corporation, 2011)ق˰βϸ, ࢹࠗфॄজؒڷͿĵՁʽ

Ҽ࢐ϸۆ؋܁३ԵڹÌڍࠞ࣊εČͲॢѓѪںԐڌॠ ʪ΀ॠČەɰ. ۋ͠ॢąڍقəইۤݓъܓԐĀę, ݓ঍ܓæ, ѕսܓæęঝέćনҾʪق˰δ३ɾݓًۆ

ÌڍÌʪ, Ìڍݓ՚֨ÂˣںČͲॠي؋܁३Եں֬֨

ॠ϶, ३Ե֨ۺڌॢԺć܁սٮ३ԵѓѪںϼঝ০ş ցॠʪ΀ॠČەɰ. ॠݓχ֬ИۺۍۺڌقەرԴ, ҝ पজࢹݗًॡقşъں˅Ժć܁սন˛ę३ԵĀęۆ

қԵقʂॢԐͻٍĵÀज़څॢ֬܁ۋɰ. ̚ॢԐϸۋ

ңĨॠəڙۍںࣷ؊ॠČʂ޾ںυʹॠşڦ३Դə֨

ėۼ޲ٮңĨইডقۙΒεş΀३آॢɰ. ॠݓχي

͠ÀݓۋڮͿۋ͠ॢş΀˞ڹ҃ۻʼݓЇॠČەə

֬܁ۋرԴ, ݓъėॡěͻۆşցۺۍÒԸۋۋΘرݓ ݓ؍Čەɰ. ٍ҆ĵə֬܃ңĨԐϸںʂԜڷͿԐϸ

ԺćۆěͻεÒԸॠəʚܼ۾ں˃Čەɰ.

ܼڅʪÀࢀҼ࢐ϸقʂ३ԴəڮॢڅՙѪфڮॢ

޲қѪˣۆ३ԵşѪںۺڌॠي؋܁Ձںࣺɳॢɰ (Korea Infrastructure Safety Corporation, 2011). ҝपজ ࢹۆսν-ًॡۺäʴقşъॠي, ݓࠗۆ॥սҼÀѺ জॠϸڮমڿͳۋѺজॠي؋܁Ձۋ۹ॠʼəìں

ČͲॣսەɰ. ˰͆Դڿͳ३Եںࣀॠيݓࠗۆڮম ڿͳۆѺʴںқԵॠəۼ޲εप॥ॣज़څÀەɰ. ҆

ٍĵقԴə ڮॢڅՙ ڿͳۤقԴ ؋ۻڱں ćԓॠي

عнॢ؋܁Ձ३Եںսॱॠٕɰ. ࣢০ҝपজࢹۆڮ

মڿͳۋ΁ں֬܃قۺڌॠيҝपজԐϸۆ؋܁ں

थÀॠəşѪقߣ۾ں˃Čەɰ.

ٍ҆ĵقԴəҝपজڮমڿͳقşъॢ(1) ॄজࢹݓ

ࠗۆ֬Ǵ֬ॹфқԵ, (2) ҝपজࢹԐϸࠞ࣊३Ե(3) ֬

܃ңĨԐͻقʂॢҝपজԐϸ؋܁३ԵڷͿĵՁʼؽɰ.

2. 2⽳⨛# ╣ㆣᷳᛃ

Lu & Likos(2006)əড়սڿͳň^Ƒε܁ۆॠيڮমڿ ͳں֩(1)ęÏۋێъজॠٕɰ.

Ͽěড়սͳ(Ɠ_ſà Ɠ_ƕ)ڹėşؓ(Ɠ_ſ)ęսؓ(Ɠ_ƕ)ۆ޲ۋ Ϳ܁ۆʼČ, ড়սڿͳڹɰڼęÏۋǣࢍǦɰ.

ň^Ƒá àÞ^Ɠſà Ɠƕß Þ^Ɠſà Ɠ_ƕ= ×ß^(2a)

ň^Ƒá à ÞƓſà ƓƕßĦ Þ^Ɠſà Ɠ_ƕ > ×ß^(2b)

Ħ á ćľƑà ľƐ

ľ à ľ_Ɛ

(2c)

يşԴ, ľ_Ƒ, ľ_ƐڹपজфۛΪߕۺ॥սҼۋɰ. ֩(2c) قԴĦəڮমपজʪۋ϶ߕۺ॥սҼľεपজ֨ф

ۛΪ֨॥սҼͿőܵজॢìۋɰ. ÂŕսؓۋتۆÉ ێ˺قəড়սڿͳڹ֩(2b)ٮÏۋÂŕսؓęʴێ ॠي֩(1)ۋTerzaghi ڮমڿͳęێ࠘ॢɰ.

ԐϸЛ܃قԴÂŕėşؓۋʂşؓۍąڍ, Ͽěড়ս ͳڹÂŕսؓۆ-1ѕÀʽɰ. ֩(2b)قԴň^Ƒá Ɠ_ƕĦÀ

ս࣢ՁčԸڷͿҙࢢĵॣսەɰ. van Genuchten(1980) ڹϿěড়սͳęڮমपজʪۆ॥ս࣢Ձěćε֩(3) ęÏۋ܃؋ॠٕɰ.

Ħ áƙ

Ɯ

ƚ

_ć

Î âå^ķÞ^Ɠſà Ɠ_ƕßæ^ƌ

Î ƛ

Ɲ

ƞ

^Ƌ⁽³⁾

पজࢹфҝपজࢹۆąڍ֩(1)ۆڮমڿͳڷͿʴ ێॢMohr-Coulomb ࣷĨőܵںǣࢍǴ϶֩(4)ٮÏ ɰ(Bishop and Blight 1963, Khalili et al. 2004, Lu and Likos 2006, Nuth and Laloui 2008, Lu et al. 2010, Oh

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Ilj1#41#Ilqlwh#hohphqw#vwuhvvhv#dorqj#wkh#vols#vxuidfh#frpelqhg#

wr# olplw# htxloleulxp# dqdo|vlv

Wdeoh# 41# Ryhuylhz# ri# dqdo|vlv# surfhgxuh#

Vwhdg|# vwdwh# lqilowudwlrq Xqvwhdg|# vwdwh# lqilowudwlrq Vwuhvv# dqdo|vlv Vorsh# vwdelolw|

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suhylrxv# udlqidoo

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¨¬_{á ć}

_ƇÞŉ Ɗ_ƀſƑƃß_Ƈ

_ƇÞŉ_ƄƊ_ƀſƑƃß_Ƈ

et al. 2012, Oh et al. 2012).

पজ֨ڮমυ޶Áۋɰ.

Ԑϸۆսν࣢ՁڹɰڼęÏڹRichardsۆѓ܁֩ڷ Ϳşցॢɰ.

¤ÞƆß

Þ

^ćŞƖ^Ï Ş^Ï¡

â ćŞƗ^Ï Ş^Ï¡

â ćŞƘ^Ï Ş^Ï¡

ß

^â^ª^{á ć}^ŞľÞƆß^Şƒ ⁽⁵⁾

يşԴ, ¤ÞƆßəսνۻʪʪ॥ս, Ɔəؓͳս˃, ¡ə

ۻս˃, Qəڮ͟, ľÞƆßəߕۺ॥սҼۋ϶, ێъۺڷͿ

¤ÞƆßٮľÞƆßəؓͳս˃ƆۆҼԸ঍॥սۋɰ.

ԐϸۆۻڿͳڹܳͿԐϸۆ঍Ԝęܼۙۆٖॳں

ыəɰ. Ը঍࢏ՁۦΒقԴۆۻڿͳقʂॢݓѕѓ܁

֩ڹԸ঍ڏʴ͟ۆ҃ܕѪ࠙قԴǣ٣ɰ.

x _ ňňâ ćƅĹ

ƀá × (6)

يşԴ, 쩒əڿͳࢮԴ, bəНߕͳѯࢢ, Ĺəݓࠗۆ֥

ڰɳڦܼ͟, gəܼͳÀ՚ʪۋɰ. ڮমڿͳڹ֩(6)ق Դĵॢۻڿͳę֩(5)ۆ३قԴĵॢÂŕսؓںۋ ڌॠيĵॠČ, ؋܁३ԵقԐڌʽɰ.

ॢćथ঍३ԵقԴəFig. 1قԴǣࢍǦটʴڙۆۼ

ठقԴتࠑϸقۚڌॠə৪ۆқपεÀ܁ॠي؋ۻ ڱق١޲Àप॥ʽɰ(Peterson 1955, Fellenius 1936, Janbu 1954, Bishop 1955, Morgenstern and Price 1965, Spencer 1967, Sarma 1973, Duncan 1996, Krahn 2003, Duncan and Wright 2005). ъϸقڮॢڅՙ३Եںࣀॠ يڿͳںćԓॠϸĵՁěćق˰͆थ঍ںۋΘʪ΀

ۼठࠑϸقۚڌॠə৪ںćԓॣսەɰ. ̚ॢ֨ėۼ

޲ق˰δݓࠗۆڿͳѺজεČͲॣսʪەɰ(Duncan 1996, Dawson et al., 1999, Griffiths and Lane 1999, Iverson 2000; Rahardjo et al. 2001, Crosta and Frattini 2003, Casagli et al. 2005, Tsai et al. 2008, Lu et al.

2013).

؋ۻڱڹটʴϸقۚڌॠəڮॢڅՙ३Ե֨ۻɳڿ ͳ쩓ٮۻɳÌʪ(֩(4))ۆ०ͳۆҼڱۋ϶, ɰڼęÏ ۋۺқʽɰ.

¨¬_{á ć}

_ƇÞŉ ƊƀſƑƃß_Ƈ

_ƇÞŉ_ƄƊ_ƀſƑƃß_Ƈ

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يşԴ, Ɗ_ƀſƑƃəۼठ۹ϸۆţۋۋ϶, iəۼठѥ঒ۋɰ.

ԐϸقԴۆۻڿͳ, Ͽěড়սͳ, ড়սڿͳқपͿҙ ࢢڮমڿͳںćԓॠϸ, Ԑϸۆ؋܁ڹҝपজࢹۆۻ ɳÌʪٮڮমڿͳқपεČͲॠيćԓॣսەɰ. ३ Եۼ޲əҝपজڮʴ, ۻڿͳқपф؋ۻڱںĵॠ əę܁ںप॥ॠ϶(Lu et al. 2013), GeoStudio 2007 ࡑ

˚ۆڿͳ३ԵϿ˗(SIGMA/W, 2007), ࠞ࣊३ԵϿ˗

(SEEP/W, 2007)ęԐϸ؋܁३ԵϿ˗(SLOPE/W, 2007) ںۋڌॠيսॱॠٕɰ. ҝपজڮʴڹÌڍق˰δ܁

ԜΪфҙ܁Ϊ३Եقۆॠيսॱॢɰ. ˃ѥݫͿۻڿ ͳқपə࢏ՁϿʝںۋڌॠيɳտॠóćԓॢɰ. ؋

܁३ԵقۺڌॠəMohr-Coulomb ࢏ՙՁϿʝںۺڌ ॠəìۋ०νۺۋݓχ, ؉ݔ३Եࡑ˚قҝपজࢹڮ মڿͳقěॢ܁֩জÀĵইʼݓ؍؉Դۺڌॣսػ ؽɰ. ࢏ՁćսəѺڦقəࡾóٖॳںǛ࠘ݓχۻڿ ͳقəࡾóٖॳںܳݓ؍əɰČÀ܁ॠٕɰ.

ҝपজڮʴфۻڿͳقʂॢڮॢڅՙ३Եںࣀॠ

(4)

+d,# Kdgrqj

+e,# Srkdqj

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يটʴϸقԴڮমڿͳęԜڿॠəۻɳÌʪεĵॣ

սەɰ(Table 1 ޷ܓ). GeoStudio 2007 ࡑ˚قԴəڿ ͳ३Եфࠞ࣊३ԵڷͿҙࢢĵॢĀęε؋܁३Ե֨

টʴϸقۺڌॣսەɰ. ࣢০॥ս࣢ՁčԸڷͿҙࢢ

ҼԸ঍ۺۍҝपজۻɳÌʪεԺ܁ॠϸ, ֩(2)ۆড়ս ڿͳۋʴێॠóۺڌʽɰ. ֨Âق˰δ؋ۻڱѺʴں

थÀॠşڦॠي, ইۤࣷĨϸںČͲॠČٚҼ३Եں

ࣀॠيČ܁ۺۍটʴϸںԺ܁ॠٕɰ.

3. ᙋ␌⏷ᶿ⪣# ཧ⧟# ὚# ⴋㆀ# ẇ⑼

ʂԜԐϸ˞ڹʪͿইۤۆۼࢹԐϸڷͿ, ݓࠗڹॄ

জʼرҝٍ՚ϸںϔڍ֮ॢҾʪͿप॥ॠČەČ, Ԑ ϸۆԜҙəۛΪࢹࠗںۋΘČەɰ. ۋٮÏڹݓݗ

঍ࢗəʂĵąҚںܼ֮ڷͿʴǫҙǴΫقԴ৖০ǣ

ࢍǦɰ. ॠʴݓًۆąڍقəজÌؒęठυؒںϿؒ

ڷͿॠəݓࠗڷͿĵՁʼرەرԴॄজࢹࠗۆ࣊ս Ձۋت঒ॠóǣࢍǦɰ. ॠʴԐϸڹşܕۆۼÒԐϸ ڷͿ2009ț7ښݚܼÌڍͿۍॠيңĨÀێرǮɰ.

प२ԐϸڹۋؒęՕێۋॄজʽۛΪࢹࠗڷͿۋΘ ر܋ەəʚ, 2010ț10ښقۼÒεٰΒॠٕČ2011ț

6ښңĨॠٕɰ. Fig. 2قəॠʴԐϸфप२Ԑϸۆݓ

ࠗқपε҃يܵɰ.

܁ঝʪ३Ե঳, Fig. 2ٮÏۋڅՙϐںۺۼॠóՃ қজॠٕɰ. ҙ܁Ϊقʂॠي, ڮ͟ąćܓæڹ֬܃Ì ڍş΀ںݓशϸقۺڌॠٕɰ. ԐϸۆąԐҙशϸق

ԴəݓॠսÀڮ߻ʾսەʪ΀Ժ܁ॠٕɰ. ࠑϸۆս˃

ąćəইۤԜডęݓॠսڦ܁҃(Web page, Integrated Groundwater Information Service)εČͲॠيԺ܁ॠٕ

ɰ. ٚҼ३Եںࣀॠي߯ՙ؋ۻڱںǣࢍǴəটʴϸ ںࣷ؊ॠٕڷ϶, ইۤقԴě޶ʽ঍ࢗٮڮԐॠóۻ ъۺۍটʴۋێرǮɰ.

ÁԐϸۆÌڍş΀ڹFig. 3قԴ҃يܵɰ. ॠʴԐϸ ڹңĨ֨ێÌڍ͟150mm ۋԜۆݚܼÌڍ(4ÒښÂ

ɀۺÌڍ͟: 1200mm ۋԜ)ÀьԦॠٕČ, प२Ԑϸڹ

ңĨ֨ێÌڍ͟100mm ۋԜۆݚܼÌڍ(3ÒښÂɀ ۺÌڍ͟: 600mm ۋԜ)ÀьԦॠٕɰ.

ۛΪࢹə҆ݗۺڷͿŒݗॠóҝİ͈֨Βε޽ࠄॠ şÀūɰ΄ɰ. ֨Βۆ޽ࠄڦ࠘ق˰͆ҝŒݗՁں҃

ۋşʪॠي߿қॢتۆ֨ॹںսॱॠيآχʂशۺ ۋČێěʽ֨ॹՁęεন˛ॣսەɰ. ۛΪࢹࠗۆң ĨɳϸٽĚقԴİ͈֨ΒфҸ΀֨Βε޽ࠄॠٕɰ.

ʂԜইۤقԴə֨ΒۆێҙقԴҝٍ՚ϸęؒठں प॥ॠٕČ, ܃ڙۋšԘ߹֨ॹ֨ΒۆąڍقəŒݗ Ձںঝ҃ॠşرͲڝɰ. ֬Ǵ֨ॹڹ॥ս࣢Ձ֨ॹę Ìʪ֨ॹںܼ֮ڷͿսॱॠٕڷ϶, ҝİ͈֨Βεۋڌ

(5)

Wdeoh# 51# Pdwhuldo# surshuwlhv# ri# vorsh# od|huv

Od|huv Vwuhvv# dqdo|vlv Vhhsdjh# dqdo|vlv Vorsh# vwdelolw|

Kdgrqj Vrlo

5䮄43⁹ 31666 315;5 3 5517; 416: 419;䮄43⁰⁹ 4;15 51; 651;

Urfn 54 83 6818

Srkdqj 5䮄43⁹ 31666 316<; 3145 5:1<6 414 6179䮄43⁰⁹ 4;17 3 6419

+d,# VZUF

+e,# K|gudxolf# frqgxfwlylw|

+f,# Vkhdu# vwuhqjwk

Ilj1# 71# Surshuwlhv# ri# xqvdwxudwhg# vrlov

ॠͲČ Ȥͳॠٕݓχ ʂҙқ İ͈֨Βۆ ֨ॹՁęε

ۋڌॣսшقػؽɰ.

ॠʴфप२ݓًԐϸقʂॢҝपজНՁ࠘εFig.

4قԴ҃يܵɰ. Fig. 4(a)قԴ҃يݓˢۋ, ؓͳࣺ߸߻

֨ॹںࣀॠي॥ս࣢ՁčԸںন˛ॠٕČ, RETC ॒ ͿŔ͖ںۋڌॠيvan Genuchten ϿʝͿধŊқԵں

ॠٕɰ(van Genuchten et al., 1991). ėş॥ۓ࠘Ɠƀٮć սn, पজߕۺ॥սҼ, ۛΪ॥սҼəTable 2ق܁νʼ ؽɰ.

ҝİ͈֨Βۆ࣊սćսə॥ս࣢ՁčԸڷͿҙࢢMualem ۋ΁قۆॠي߸܁ॠəѓѪںۋڌॠٕɰ. ŔĀę

Fig. 4(b)ٮÏۋथÀʼؽڷ϶, ٚҼ३Եę܁قԴć սٍĵεࣀॠيपজ࣊սćսεԺ܁ॠٕɰ. ॄজؒ

قʂॠي, ॥ս࣢ՁčԸڹۛΪࢹٮʴێॠóÀ܁ॠ

ٕɰ. ॄজؒۆ ࣊սćսčԸڹ ۛΪࢹۆ ࣊սćսٮ

ʴێॠóÀ܁ॠٕڷ϶, Table 2ق܁νॠٕɰ.

Ԙ߹֨ॹقԴəपজܓæقԴݔۿۻɳ֨ॹںսॱ ॠٕɰ. ҝपজܓæقԴəϿěড়սͳںܓۼॠيԘ

߹֨ॹںսॱॠٕɰ. ֨Βəইۤ॥սҼфнʪॠ قԴ܁ۺɰݙڷͿİ͈֨ΒεۦՁ঍ॠيսॱॠٕɰ.

Fig. 4(c)قԴəড়սڿͳقŖäॢڮমڿͳقʂॢԘ

߹֨ॹĀęε҃يܵɰ. ۋ˺p’, qəɰڼęÏۋ܁

ۆʽɰ.

SWRC ֨ॹڷͿҙࢢĵॢۻɳÌʪÀԘ߹֨ॹڷͿ ҙࢢĵॢ֬ॹ࠘ε०νۺڷͿٚࠑॣսەؽɰ. ɰت

ॢϿěড়սͳقʂॠيڮমڿͳڷͿşցॢۻɳÌ ʪəڮێॢࣷĨप͇Ըڦقܕۦॢɰ. ࣢০पজ֨ࣷ

ĨőܵęʴێॢࣷĨőܵڷͿ܁ۆॣսەڼں؎ս

ەɰ(Bishop and Blight 1963, Khalili et al. 2004, Lu and Likos 2006, Nuth and Laloui 2008, Lu et al. 2010, Oh et al. 2012, Oh et al. 2012). ۋͿҙࢢFig. 4(a)قǣࢍǦ

(6)

+d,# Dsulo# 48/# 533<

+e,# Mxo|# 49/# 533<

Ilj1# 81# Vxfwlrq# vwuhvv# +nSd,# glvwulexwlrqv# dv# iorzv# +Kdgrqj,

+d,# Ghjuhh# ri# vdwxudwlrq# yv1# wlph/

+e,# Sruh# zdwhu# suhvvxuh# yv1# wlph

Ilj1# 91# Zhwqhvv# yduldeohv# rq# wkh# vols# vxuidfh# +Kdgrqj,

+d,# Pdufk# 64/# 5344

+e,# Mxqh# 5:/# 5344

Ilj1# :1# Vxfwlrq# vwuhvv# +nSd,# glvwulexwlrqv# dv# iorzv# +Srkdqj,

SWRCÀ֩(4)ۆۻɳÌʪεҝपজڮমڿͳ(֩(1)) ڷͿۺۼॠóşցॣսەڼںঝۍॠٕɰ.

4. འ⧻⤛# ᡻᳃# ⃓㜷㦟# ㆳ㕷ྻᜤ

ԸॱÌڍ͟ڹʂԜЛ܃قۺ०ॠóԸ܁ॠٕɰ. ॠ ʴԐϸڹԐϸۼÒ঳սț঳قңĨÀێرǦԐͻͿ

äۆٍۙԐϸęÏڹԜࢗεǣࢍǴČەؽɰ. ԸॱÌ ڍə1țÂٍथŒÌڍ͟ڷͿԓ܁ॠٕɰ(2.86e-8m/s, ț902mm). ъϸप२ԐϸڹԐϸۼÒ঳1țۋǴق

ңĨÀێرǮڷ϶, 1ÒښÂۆथŒÌڍ͟(5.60e-9m/s, ښ15mm)ںԸॱÌڍͿԺ܁ॠٕɰ.

ॠʴԐϸۛΪࢹࠗۆড়սڿͳ(֩(2)) қपəFig. 5 ٮÏۋǣࢍǮɰ. Fig. 5(a)قԴəҝपজࠗۆ܁ԜΪ३ ԵڷͿǣࢍǦߣşড়սڿͳқपε҃يܵɰ. ۻțʪ

ٍथŒÌڍقۆॠي, ড়սڿͳڹ-40kPaقԴ0kPa܁ʪ ͿǣࢍǮڷ϶қपۆتԜڹŪۋق˰͆ݒÀॢɰ.

ҙ܁Ϊ३ԵقԴəÂŕսؓۋݒÀॠيपজʪÀ

ݒÀॠ϶ݓॠսڦÀɰՙԜ֧ॠٕɰ. ԐϸңĨÀێ رǦ2009țʪ7ښ16ێقəFig. 5(b)ٮÏڹড়սڿͳ

қपÀćԓʼؽڷ϶, ࣷĨϸܳѺقԴ-5kPa ۋԜۍ

ًٖۋঝۤʼČەɰ.

Fig. 6قԴəۻъۺটʴϸقԴҝपজࢹۆ֥ڰʪ

(7)

+d,# Ghjuhh# ri# vdwxudwlrq# yv1# wlph

+e,# Sruh# zdwhu# suhvvxuh# yv1# wlph

Ilj1# ;1# Zhwqhvv# yduldeohv# rq# wkh# vols# vxuidfh# +Srkdqj,

+d,# Kdgrqj

+e,# Srkdqj

Ilj1# <1# Idfwru# ri# vdihw|# iru# olplw# htxloleulxp# phwkrg# dqg# ilqlwh#

hohphqw# phwkrg

Ѻս˞ۆ֨Âق˰δѺজε҃يܵɰ. पজʪəԜҙ قڦ࠘ॢ۾aٮb(Fig. 2(a))قԴ65%قԴ100%Ϳݒ ÀॠČەɰ. টʴϸॠҙcقԴəपজʪÀԜʂۺڷ ͿȭóǣࢍǣČەɰ. Fig. 6(b)قԴəपজʪÀݒÀ

॥ق˰͆ÂŕսؓʪݒÀॠəìں҃يܳČەɰ. ࣢ ০ңĨÀێرǦ2009țʪ7ښ16ێИͷقəݚܼÌ ڍͿۍॠيটʴϸۆॠҙݓ۾قԴəÂŕսؓۋت ۆÉںǣࢍǶɰ.

प२ԐϸۛΪࢹࠗۆড়սڿͳқपəFig. 7ęÏۋ

ǣࢍǮɰ. Fig. 7(a)قԴəҝपজࠗۆ܁ԜΪ३ԵڷͿ

ǣࢍǦߣşড়սڿͳқपε҃يܵɰ. ۻښښथŒÌ ڍقۆॠي, սؓڹ-80kPaقԴ-30kPa܁ʪͿǣࢍǮ ɰ. ҙ܁Ϊ३ԵقԴə, ÂŕսؓۋݒÀॠيपজʪÀ

ݒÀॠ϶ݓॠսڦÀɰՙԜ֧ॠٕɰ. Fig. 7(b)ۆԐ ϸңĨ֨ড়սڿͳڹࣷĨϸܳѺقԴ-5kPa ۋԜۍ

ًٖۋঝۤʼČەɰ.

Fig. 8(a)قԴəۻъۺটʴϸقԴҝपজࢹۆपজ ʪۆ֨Âق˰δѺজε҃يܵɰ. पজʪəটʴϸق ԴۻߕۺڷͿ90%قԴ100%ͿݒÀॠČەɰ. Fig.

8(b)قԴəपজʪÀݒÀ॥ق˰͆Âŕսؓʪ-80kPa قԴ0kPa ۋԜڷͿݒÀॠəìں҃يܳČەɰ.

5. ⃓㜷㦟⏷ᶿ⪣# ⢓⭠㢿⑨

ॠʴԐϸڹي͠३؋܁ՁقۋԜۋػۋėڌܼۋ ʏԐϸۋɰ. ңĨ֨ێÌڍ͟150mm ۋԜۆݚܼÌڍ ÀьԦॠٕČ, ęʪॢÌڍͿۍॠيݓࠗǴقपজʪ ÀݒÀॠČێҙًٖڹٰۻपজԜࢗεǣࢍǶɰ (Fig. 5(b)). प२ԐϸڹңĨ֨ێÌڍ͟100mm ۋԜۆ

ݚܼÌڍÀьԦॠٕɰ. ۋͿۍॠي֨ė঳ێ܁şÂ

؋܁ՁقЛ܃ÀػʏԐϸۆңĨÀьԦॠٕɰ.

ۋ͠ॢ؋܁ՁѺʴںڮমڿͳقşъॢҝपজ؋

܁Ձ३ԵںࣀॠيқԵॣսەؽɰ. ٍ҆ĵۆ३Ѫ ڹڮॢڅՙ(FE) ڿͳۤقԴۼठقۚڌॠə৪қप قʂॠي؋ۻڱںćԓॢɰ. ۋ͠ॢ३Ѫڹॢćथ঍

Ѫ(LE)قҼॠي३ۆعнʪεȭێսەɰ. Fig. 9ق Դə2ÒইۤقʂॠيFEٮLEۆ؋ۻڱںҼİॠČ

ەɰ.

Fig. 9(a)قԴəॠʴԐϸۆܳرݕটʴϸ˞قʂॠ ي֨Âق˰δ؋ۻڱں҃يܵɰ. 2009ț7ښ, ۻъۺ ۍԐϸটʴۋьԦॠٕČ؋ۻڱڹ1.0ۋॠͿ֬܃ࣷ

ĨεϿۆॣսەؽɰ. ߣşق؋ۻڱڹ1.4܁ʪݓχ

(8)

+d,# Kdgrqj

+e,# Srkdqj

Ilj1# 431# Hiihfwlyh# vwuhvv# glvwulexwlrq# dorqj# wkh# vols# vxuidfh

ݚܼÌڍͿۍॠي1.0ۋॠūݓ۾޲Çՙॠٕɰ. LE ؋ ۻڱۋFEۆąڍقҼॠي10% ܁ʪǰóǣࢍǦɰ.

Fig. 9(b)قԴəप२Ԑϸۆܳرݕটʴϸ˞قʂॠ ي֨Âق˰δ؋ۻڱں҃يܵɰ. 2011ț6ښ, ۻъۺ ۍԐϸটʴۋьԦॠٕČ३Ե֨ćԓʽ؋ۻڱڹ1.0 ڷͿ֬܃ࣷĨεϿۆॣսەؽɰ. ߣşق؋ۻڱڹ

2.8܁ʪݓχݚܼÌڍͿۍॠي1.0ūݓ۾޲Çՙॠٕ

ɰ. प२ԐϸۆąڍقʪFE ؋ۻڱۋLE ؋ۻڱ҃ɰ

ɰՙࡾóćԓʼݓχڮԐॠóǣࢍǮɰ.

Fig. 10(a)قԴəॠʴԐϸۆࠞ࣊Ϳۍॠيটʴϸ قԴÂŕսؓۋݒÀॠيڮমڿͳۋÇՙॠəìں

҃يܵɰ. ܁ԜΪ३Ե঳, ÁۼठقԴəߣşÂŕսؓ

ۋ-60قԴ-10kPaūݓǣࢍǦɰ. ҙ܁Ϊ३Եقۆॠي

Âŕսؓڹ۾޲ͿݒÀॠ϶, টʴϸًٖقԴəĶҙ ۺڷͿपজԜࢗقۋΚɰ. ˰͆ԴÂŕսؓۋ1060kPa

܁ʪݒÀॠٕɰ. ÂŕսؓۆѺজܼ͟قԴێҙÀҝ पজڮমڿͳقşيॠيۻъۺڷͿ40kPa ܁ʪÇՙ ॠٕɰ.

Fig. 10(b)قԴəप२Ԑϸۆࠞ࣊Ϳۍॠيটʴϸ قԴÂŕսؓۋݒÀॠيڮমڿͳۋÇՙॠəìں

҃يܵɰ. ܁ԜΪ३Ե঳, ÁۼठقԴəߣşÂŕսؓ

ۋ-100قԴ-40kPaūݓǣࢍǦɰ. ҙ܁Ϊ३Եقۆॠ يÂŕսؓڹ۾޲ͿݒÀॠ϶, টʴϸقԴəपজԜ

ࢗقۋΘČڮমڿͳۋ߯ʂ80kPa ܁ʪÇՙॠٕɰ.

ॠʴԐϸڹңĨ֨ێÌڍ͟150mm ۋԜۆݚܼÌ ڍÀьԦॠٕČ, ۋͿۍॠيێرǦңĨইԜںڮম ڿͳںČͲॢ३ԵڷͿٚࠑॣսەؽɰ. प२Ԑϸڹ

ңĨ֨ێÌڍ͟100mm ۋԜۆݚܼÌڍÀьԦॠٕ

ɰ. ۋͿۍॠي֨ė঳ێ܁şÂ؋܁ՁقЛ܃Àػ ʏԐϸۆңĨÀьԦॠٕڷ϶, ࠞ࣊εČͲॢڮমڿ ͳ३Եۼ޲εࣀॠيԐϸۆңĨڙۍںőϼॣսە ؽɰ.

6. ࿻# ᮫

ٍ҆ĵقԴəॠʴęप२ݓًۼÒԐϸقԴێرǦ

֬܃ңĨԐͻεܼ֮ڷͿҝपজࢹۆڮমڿͳقşъ

ॢԐϸңĨşĵ(mechanism)εۦইॠٕɰ. ʂԜݓً

قʂॠي֨Βε޽ࠄॠČҝपজНՁں֬ॹۺڷͿ

ন˛ॠٕڷ϶, ֬܃ Ìڍş΀ں ČͲॠي ইۤԜডں

ۦইॠيÌڍࠞ࣊قۆॢԐϸ؋܁ՁѺʴںۦইॠ

ٕɰ. ۋεࢹʂͿ, Ìڍ֨ࠞ࣊εČͲॢ؋܁३ԵşѪ ۋ֬ڌۺڷͿ֬Иقۺڌॣսەڼںۓݒॠٕɰ. ࣢ ০ࠞ࣊֨ڮমڿͳѺজÀҝपজԐϸۆңĨεێڷ

ࢅəşĵεۓݒॠٕɰ. ۋε܁νॠϸɰڼęÏɰ.

(1) ॠʴԐϸфप२ԐϸۆۛΪࢹԐϸقʂॢܓԐ εսॱॠيইۤş΀фҝपজНՁںন˛ॠٕ

ɰ. ҝपজۻɳÌʪə॥ս࣢ՁڷͿҙࢢড়սڿͳ ںԓ܁ॠيपজࢹٮʴێॢࣷĨőܵڷͿ܁ۆॣ

սەؽɰ.

(2) ࠞ࣊३ԵںսॱॢĀęॠʴԐϸڹ4ÒښÂɀۺ

Ìڍ͟: 1200mm ۋԜۋьԦॠٕČ, ęʪॢÌڍͿ

ۍॠيݓࠗǴقपজʪٮÂŕսؓۋݒÀॠيң Ĩ֨قə ێҙ ًٖڹ ٰۻ पজԜࢗε ǣࢍǻɰ.

प२Ԑϸڹ3ÒښÂɀۺÌڍ͟: 600mm ۋԜۋь ԦॠيपজʪÀݒÀॠəìں३Եॣսەؽɰ.

(3) ҝपজࢹڮমڿͳقşъॠيۻɳÌʪεԓ܁ॠ ČڮॢڅՙڿͳۤقԴڮমڿͳںćԓॠي؋ۻ ڱںԓ܁ॠٕɰ. ॠʴԐϸęप२ԐϸقԴңĨ֨

؋ۻڱ1.0ںćԓॣսەؽČ, ॢćथ঍ѪقҼॠ يعнॢ३Եںսॱॠٕɰ. ۋͿҙࢢÌڍࠞ࣊

֨ҝपজࢹۆڮমڿͳق˰δԐϸۆ؋܁Ձ३ ԵşѪںêݒॣսەؽɰ.

(9)

ཛ⏷⪣# ᅋ

ٍ҆ĵəĶࢹİࣀęॡşցݕ৞ڙ(ę܃ѥ঒: 11ݓ

ًşցআ֪D04) фॢĶٍĵۦɳ(2012R1A1A2001001) ۆՁęͿԴٍĵҼݓڙقÇԐ˚ςɦɰ.

⾃ါẃ㤗# (References)

1. Integrated Groundwater Information Service, www.gims.go.kr (In Korean) ሇႚ⹚㧲⚲ⲯ↎◖㗊# 㫢㠲Ⰾ⹚, www.gims.go.kr 2. Daily rainfall record data, Korea Meteorological Administration,

www.kma.go.kr/weather/observation/past_table.jsp?stn=108&yy=

2013&obs=21&x=7&y=14 (In Korean) ዊ╛ㅇ#㫢㠲Ⰾ⹚, ⹚╛ᆚ㊻Ⱚ ᵦ, www.kma.go.kr/weather/observation/past_table.jsp?stn=108&yy=

2013&obs=21&x=7&y=14

3. Korea Infrastructure Safety Corporation (2011), Design guide on engineered slopes. (In Korean) 㧶ሇ❶▾⧢ⲞᆚṆᆏគ#(2011), ᄎ

▾ᆏ╆# ⋞㕢Ἆ# ▾ᅞዊ⶚(⧢).

4. Bishop, A. W. (1954), “The use of pore water coefficients in practice”, Géotechnique, 4(4), pp.148-152.

5. Bishop, A. W. (1959), “The principle of effective stress”, Teknisk Ukeblad I Samarbeide Med Teknikk, Oslo, Norway, 106(39), pp.

859-863.

6. Casagli, N., Dapporto, S., Ibsen, M., Tofani, V., and Vannocci, P. (2005), Analysis of the landslide.

7. Crosta, G.B. and Frattini, P. (2003), Distributed modelling of shallow landslides triggered by intense rainfall. Natural Hazards and Earth System Sciences 3, 81-93.

8. Dawson, E.M., Roth, W.H., and Drescher, A. (1999), “Slope stability analysis by strength reduction”, Geotechnique 49(6), 835-840.

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Received : October 8^th, 2013 Revised : November 11^th, 2013 Accepted : November 28^th, 2013