강우사상의 영향을 고려한 불포화 풍화사면의 안정성

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[email protected])

Received October 7 2012, Revised October 29 2012, Accepted April 1 2013

Copyright ⵑ 2013 by the Korean Society of Civil Engineers

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)

ABSTRACT

In this study, two rainfall patterns are utilized for practical consideration of rainfall phenomena in unsaturated soil slope design. One is the I.D.F (Intensity-Duration-Frequency) method which is an existing design rainfall method and ignores the effect of the variation of the rainfall according to the time. The other is the Huff method which considers this effect oppositely. First, the safety of factor of the slope according to the variation of an initial suction which means the precedent rainfall effect was examined by means of the application of the I.D.F method. Through the application of two rainfall patterns, it was discussed how the rainfall pattern affects the factor of safety of the slope. As a result, it is found that the Huff method is more practical on the evaluation of the slope stability than the I.D.F method.

Key words : Rainfall pattern, I.D.F method, Huff method, Slope stability, Initial suction

Ⅹಾ

ᔍ໕ᦩᱶ⧕ᕾ᜽, ᔍ໕❭ƕ᮹ᵝᬱᯙᯙvᬑᔍᔢ᮹⩥ᝅᱢᱲ༊ᮥ᭥⦹ᩍᅙᩑǍᨱᕽ۵݅ᮭࢱaḡႊჶᮥ₥┾⦹ᩡ݅. ⦹ӹ۵᜽eᨱ঑ෙ

vᬑపᄡ⪵᮹ᩢ⨆ᮥྕ᜽⦽ʑ᳕᮹ᖅĥvᬑႊ᜾ᯙI.D.F(Intensity-Duration-Frequency)łᖁᮥᯕᬊ⦹۵ႊჶᯕ໑, ݅ෙ⦹ӹ۵᜽e᮹

ᩢ⨆ᮥŁಅ⦹ᩍvᬑᔍᔢᮥ⢽⩥⦽Huff ႊჶᯕ݅. ຝᱡI.D.F ႊჶ᮹vᬑᔍᔢᮥᱢᬊ⦹ᩍᖁ⧪vᬑ⬉ŝෝӹ┡ԕ۵Ⅹʑ⯂ᙹಆ᮹ᄡ⪵ᨱ

঑ෙᔍ໕᮹ᦩᱥᮉ᮹ᄡ⪵ෝ᦭ᦥᅕᦹ݅. ੱ⦽, ࢱvᬑᔍᔢ᮹ႊ᜾ᮥᱢᬊ⦹ᩍvᬑᔍᔢᯕᔍ໕᮹ᦩᱥᮉᄡ⪵ᨱၙ⊹۵ᩢ⨆ᮥȽ໦⦹Łᯱ

⦹ᩡ݅. əđŝ, Huff ႊჶ᮹vᬑᔍᔢᯕI.D.F ႊჶᅕ݅޵⩥ᝅᱢᮝಽᔍ໕᮹ᦩᱥᖒ⠪aaᯕ൉ᨕḩᙹᯩᮭᮥ⪶ᯙ⧁ᙹᯩᨩ݅.

áᔪᨕ vᬑᔍᔢ, I.D.F ႊჶ, Huff ႊჶ, ᔍ໕ᦩᱶ, Ⅹʑ⯂ᙹಆ

1. ᕽು

ᬑญӹ௝ǎ☁᮹63.7%aᔑḡಽᯕ൉ᨕᲙᯩ۵ߑᯙǍ➞₞ŝᯕᨱ঑ෙ}ၽಽᯙ⧕ᇡᙹᱢᮝಽᵝÑḡၰࠥಽᄡᨱᕽᯙŖᱢᯙ

ᔍ໕ᮥᛞíᱲ⧁ᙹᯩ݅(Chang 2012). ⦽⠙ʑᔢᄡ⪵ಽᯙ⦽┽⣮ŝ⪙ᬑಽᔑᔍ┽᮹ၽᔾኩࠥa᷾a⇵ᯕᨱᯕಽᯙ⦽ᯙ໦ŝ

ᰍᔑ ⦝⧕a ኩჩ⦹í ၽᔾ⦹Ł ᯩ݅. ✚⯩ ʑᔢ᮹ ɪĊ⦽ ᄡ⪵ಽ vᬑ᮹ ➉▕ᯕ ᄡ⦹Ł ᯩ۵ ᝅᱶᮝಽ ʑ᳕ ႊ᜾ᅕ݅۵ ᄡ⪵⦹۵

⪹Ğ᳑Õᮥ Łಅ⦽ ᔍ໕ᨱᕽ᮹ ᦩᱶᖒ ⠪aa ⩥ᝅᱢᯙ ݡᦩᮝಽ ᯙ᜾ࡹŁ ᯩ݅.

ʑ᳕᮹ šಉ ᩑǍॅᮥ ᔕ⠕ᅕ໕ ᵝࡽ ᔍ໕❭ƕ ၽᔾ ᬱᯙᯕ ᱩ☁ಽ ᯙ⦽ ᦩᱶᖒ qᗭ᪡ ⣮⪵ Ⅺḥ ॒ᮝಽ ḡၹ᮹ vࠥqᗭ ၰ

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Fig. 1. Conceptual View of Unsaturated Slope Failure due to Rainfall

Fig. 2. Definition of Average Maximum Rainfall Intensity

ᔍ໕ԕ⋉⚍ᙹᨱʑᯙ⦹Łᯩ۵äᮝಽ᦭ಅᲙᯩ݅(Krahn et

al. 1989; Fredlund and Rahardjo 1993; Lambe 1996; Ng and Shi 1998, Chang 2012). ঑௝ᕽǎԕᨱᕽࠥvᬑ᜽ᔍ໕❭ƕ᮹

ີ⍅ܩ᷹ᮥᯕ⧕⦹ʑ᭥⦽ᩑǍॅᯕ⪽ၽ⯩ḥ⧪ࡹŁᯩ݅. ᯕ్⦽

יಆ᮹ᯝ⪹ᮝಽᔍ໕ᦩᱶᖒ⠪aᨱʑ᳕᮹⡍⪵☁ႊ᜾᮹ᱢᬊᅕ

݅۵ᇩ⡍⪵ḡၹ᮹ᯕುᱢᬊᯕᅕ݅⩥ᝅᱢᯙݡᦩᮝಽᯱญᰂŁ

ᯩ݅(Kim et al. 2002; Park and Shin 2009; Lee et al. 2009;

Oh et al. 2008; Ng and Shi 1998; Rahardjo and Leong 1997;

Kim et al. 2004).

঑௝ᕽᅙםྙᨱᕽ۵ǎԕ⣮⪵☁᜽ഭෝݡᔢᮝಽᇩ⡍⪵☁

ᔢ┽ෝŁಅ⦽ᯕುᮥᱢᬊ⦹ᩍḡၹ᮹ᇩ⡍⪵⧉ᙹ✚ᖒᮥ᦭ᦥᅕ Łᮁ⦽᫵ᗭ⥥ಽəఉSeep/w᪡Slope/w (Geo-Slope 2004)ෝ

⪽ᬊ⦹ᩍ ᜽eᱢ ᇥ⡍ෝ Łಅ⦽ vᬑᔍᔢᮥ ᱢᬊ⦽ ⬥ ᇩ⡍⪵

⋉⚍ ၰ ᔍ໕᮹ ᦩᱶᖒ ⠪aෝ bb ᝅ᜽⦹ᩡ݅.

2. vᬑᔍᔢ

vᬑᔍᔢᮡ᜽eᨱ঑ෙvᬑప᮹➉▕ᮥ᮹ၙ⦹۵ߑb᳦☁༊

Ǎ᳑ྜྷᮥᖅĥ⦹۵ߑŁಅࡹ۵ᵲ᫵⦽᫵ᗭᯕ݅. ✚⯩ᔍ໕᮹Ğᬑ

vᬑᔍᔢᯕၙ⊹۵ᩢ⨆ᮡๅᬑⓍ໑ᯕෝᱢᬊ⧉ᨱᯩᨕ᜽eᱢ

ᩢ⨆ᮥ Łಅ⦹ḡ ᦫᮡ I.D.F łᖁŝ ᜽eᱢ ᇥ⡍ᨱ ঑ෙ Huff

ႊჶᮥbb⧕ᕾŝᇥᕾᨱᱢᬊ⦹ᩍə₉ᯕෝᔕ⠕ᅕŁᯱ⦹ᩡ݅.

2.1 I.D.F ࢺ࣑

I.D.F (Intensity-Duration-Frequency)۵ᯝ᳦᮹ɚ⊹vᬑప ᮹ᇥᕾđŝಽᯕෝᔑᱶ⧁ভݡᔢvᬑᔍᔢᮡ☖ĥ⦺ᱢࠦพᖒ᮹

aᱶᮥᮁḡ⧁ᙹᯩࠥಾᇥญࡹ໑, ᯕভᔍᬊࡹ۵ʑᵡᮡᅕ☖

vᬑᔍᔢe᜽eeĊᮝಽᇥญࡽ݅. bࠦพᔍᔢᨱᕽ↽ݡ⠪Ɂ

vᬑvࠥෝFig. 2᪡zᯕbḡᗮʑeᄥಽᔑᱶ⦹ᩍᇥᕾ༊ᱢᨱ

঑௝ᩑ↽ݡ⊹ĥᩕŝᩑⅩŝ⊹ĥᩕ॒ᮥǍᖒ⦽݅. ᯕভb

⪙ᬑಽᇡ░↽ݡ⠪Ɂvᬑvࠥෝᖁᄥ⦹۵ߑᯩᨕᝅᱽvᬑḡᗮ ʑeᅕ݅޵ʕḡᗮʑe᮹Ğᬑ, ⅾvᬑపᮥᵝᨕḥḡᗮʑeᮝಽ

ӹٵᮝಽ៉ ↽ݡ ⠪Ɂ vᬑvࠥෝ ĥᔑ⦽݅.

ᩩෝॅᨕ, ᝅᱽvᬑపᯕ30ᇥḡᗮࡹŁⅾvᬑపᯕ20mmᯝ

ভ40ᇥḡᗮʑe᮹⠪Ɂvᬑvࠥ۵(20/40)×60=30 mm/hrᯕŁ, 60ᇥᯙĞᬑ۵(20/60)×60=20 mm/hraࡽ݅. ᯕ᪡zᯕḡᗮʑe ᄥ↽ݡ⠪Ɂvᬑvࠥ᮹ĥᔑᨱᯩᨕš⊂ᯱഭ᮹݉᭥᜽eeĊᨱ

঑௝Łᱶ᜽eŝᯥ᮹ḡᗮʑe᮹ྙᱽa᧝ʑࢁᙹᯩ݅. ᯕ౨í

Ǎᖒࡽĥᩕᮥᯕᬊ⦹ᩍᯕುᱢ⪶ශᇥ⡍⧉ᙹᨱ᮹⧕ᙹ⦺ᱢᮝಽ

༉⩶⪵᜽┅Ñӹࠥ᜾ᱢႊჶᨱ᮹⧕⧕ᕾ⦹ᩍᰍ⩥ʑeᄥ, ḡᗮʑ eᄥᨱ ঑ෙ vᬑvࠥ᜾ᯕӹ I.D.F šĥłᖁᯕ ᨜ᨕḥ݅. Fig.

2᪡ zᯕI.D.Fᨱᕽ۵bḡᗮʑeᄥ ↽ݡ⠪Ɂvᬑvࠥ⪚ᮡ

vᙹపᮥŁಅ⦹ʑভྙᨱbḡᗮʑeԕ⪙ᬑ᮹᜽eᱢᄡ⪵ෝ

ᱥ⩡Łಅ⦹ḡ༜⦽݅. ঑௝ᕽᖅĥ⪙ᬑᨱᕽࠥš⊂⪙ᬑ᪡zᯕ

᜽eᱢ ᇥ⡍ෝ Łಅ⧕᧝ ⦽݅.

2.2 Huff ࢺ࣑

1967֥Huff۵ၙǎᯝญיᯕᵝ᮹vᬑʑಾᮥ☖ĥ⦺ᱢᮝಽ

ᇥᕾ⦹ᩍvᬑప᮹᜽eᱢᇥ⡍ෝӹ┡ԕ۵ ྕ₉ᬱ᜽eᇥ⡍ł ᖁᮥᱽ᜽⦹ᩡ݅(Huff 1967; 1970). ᯕ۵Fig. 3ŝzᯕvᬑ᮹

٥ałᖁᮥᯕᬊ⦹ᩍ, ᱥḡᗮʑeᮥ4॒ᇥ⦹ᩡᮥভᇥඹࡽǍe ᨱᕽᬑప᮹↽ݡᇡ᭥aᨕ۱ᇡᇥᨱᕽӹ┡ӹ۵ḡ᳑ᔍ⦹ᩡ݅.

ᯕ᪡zᯕ4}ə൚ᮝಽᇥඹࡽvᬑෝ᜽eᱢᮝಽྕ₉ᬱ⪵

᜽┅ʑ᭥⦹ᩍ}}vᬑ᮹٥aḡᗮʑeŝᯕᨱ঑ෙvᬑపᮥ

bb႒ᇥᮉಽ⢽᜽⦹Ł, ᯕෝ᜾ᮝಽӹ┡ԕ໕݅ᮭ᜾(1)ŝ(2)᪡

z݅.

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Fig. 3. Time Distribution of Rainfall Pattern by Huff Method

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(2)

ᩍʑᕽ, PT(i): ᯥ᮹᜽e T(i)ᨱᕽ᮹ vᬑḡᗮʑe እ, T(i):

vᬑ᜽᯲ ⬥ ‘i’ჩṙ ᜽b᮹ Ğŝ᜽e, T0: ⅾ vᬑḡᗮʑe, i:

݉᭥᷾ᇥ⬀ᙹ, PR(i): ᯥ᮹᜽eT(i)ᨱᕽ᮹vᬑపእ, R(i): ᯥ᮹᜽

e T(i)ʭḡ᮹ ٥aᬑప, R0: ḡᗮʑe, T0᮹ ⅾ ᬑపᯕ݅.

ᯕ᪡zᯕྕ₉ᬱ٥ałᖁᮥᯕᬊ⦹ᩍbə൚ᨱᗮ⦽⪙ᬑॅᮥ

ᇥญ⦹ᩍᇥᕾ⦽݅. ຝᱡ, ᱽ1Ǎe⪙ᬑᇥᕾᯝĞᬑbḡᗮʑe

᷾ᇥ⫭ᙹᄥಽb⪶ශᮥ⇵ᱶ⦽⬥, b⪶ශᄥಽ᜽eᇥ⡍ෝ⇵ᱶ⦽

݅. ᯕভb⪶ශ٥ałᖁᮡ10%᮹⪶ශeĊᮝಽ᯲ᖒ⦹۵äᯕ

ᯝၹᱢᯕ݅. ᩍʑᕽ, ⪶ශ٥ałᖁᮡᵝᨕḥə൚ᨱݡ⧕⦽ᗮᖒ᮹

⊂ᱶᯱഭෝaḡŁ٥a႒ᇥᮉੱ۵٥aኩࠥ⢽ෝ᯲ᖒ⦹ᩍᯕෝ

ࠥ⢽⪵⦽äᮝಽ, bɪe᮹ᱶ⪶ᔢ⦽ĥၵಽၲʭḡ״ᩍᯩ۵

ᔍಡ᮹ ᱥℕ ᔍಡᨱ ݡ⦽ እᮉಽ៉ ⢽⩥ࡽ݅.

Huff ႊჶᮡbḡᗮʑeᨱ঑ෙ⪙ᬑ᮹ᖒḩᨱ঑௝᳑Õᇡ

⪶ශ}ֱᮥ᯦ࠥ⦹ᩍྕ₉ᬱłᖁᮥb᳑Õᄥಽᔍᬊ⧁ᙹᯩᮝӹ, ᯕෝᬑపᵝᔢࠥಽ᯲ᖒ⦹ʑ᭥⧕ᕽ۵ࠥ᜾ᱢʑჶᯕӹ⫭ȡ᜾ᨱ

᮹⦽ ʑჶॅᯕ ⦥᫵⦹݅. ྜྷು ⫭ȡ᜾ᨱ ᮹⦽ ʑჶᮡ ⍕⥉░᮹

ၽݍŝ⧉̹ᛞí⪽ᬊ⧁ᙹᯩ݅. ə్ӹᔍᬊࡽ⧉ᙹaᔢݡᱢᮝ ಽᱡ₉ᬱ(3₉ᯕ⦹)᮹⧉ᙹ௝໕٥ałᖁ᜾ᮥᱶ⪶⦹í⢽⩥⧁

ᙹᨧ݅. อ᧞Ł₉ᬱ᮹⧉ᙹෝᔍᬊ⦹໕ᇥᕾᮡᔢݡᱢᮝಽ⯹ॅᨕ ḡíࡽ݅. ੱ⦽⪙ᬑᖁᱶᨱᯩᨕ݉ᯝ⪙ᬑᔍᔢ᮹ᱥ⬥ಽ6᜽e

ᯕᔢᯕྕvᬑᯕ໕, ⦽⪙ᬑಽᱶ᮹⦹Łᯩḡอᯕ౨í⦽⪙ᬑಽ

ᇥญࡹ۵ ʑᵡᮡ ᦥḢ ᙹྙ⦺ᱢᮝಽ ᷾໦ࡹḡ ᦫᦹ݅.

3݉ĥྕ₉ᬱ٥aᬑపsᮥᯕᬊ⦹ᩍྕ₉ᬱᬑపᵝᔢࠥෝ᯲ᖒ⦽

݅. ྕ₉ᬱ ٥aᬑప sᮡ ḡᗮʑeᮥ 10}ಽ ӹ٥ᨩᮥ

ভ᮹٥aᬑపᯕအಽ⬥⧪sᨱᕽᖁ⧪sᮥዝᵝᨕྕ₉ᬱ

ᬑపᵝᔢࠥෝ᯲ᖒ⦽݅. ə్ӹᮁ⇽⧕ᕾᮥ⦹ʑ᭥⧕ᕽ

ḡᗮʑeᮥ10}ᅕ݅ᱢÑӹฯíӹ٭⦥᫵aᯩ݅. ᯕভ ۵ࠥ᜾ᱢʑჶᯕӹ⫭ȡႊᱶ᜾᜾(3)ᮥᯕᬊ⦹ᩍྕ₉ᬱ

٥aᬑపsᮥᰍ᯲ᖒ⦹ᩍ, ྕ₉ᬱᬑపᵝᔢࠥෝĥᔑ⦽݅.

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ᩍʑᕽ, Y(%)۵ ٥aᬑప, X(%)۵ ḡᗮʑeᯕŁ, C0, C1, C2,ⲷ, Cnᮡ ḡᩎᨱ ঑ෙ ᔢᙹᯕ݅.

4݉ĥ ྕ₉ᬱ ᬑపᵝᔢࠥෝ ᖅĥᬑపᵝᔢࠥಽ ᱥ⪹⦽݅. ྕ₉ ᬱᬑపᵝᔢࠥ۵႒ᇥᮉಽࡹᨕᯩʑভྙᨱᖅĥᬑపᵝᔢ

ࠥෝǍ⇶⦹ʑ᭥⧕ᕽ۵1݉ĥᨱᕽđᱶ⦽vᬑʫᯕၰ

ḡᗮʑeᮥ ྕ₉ᬱ ᬑపᵝᔢࠥ sᨱ Œ⦽݅.

3. ᇩ⡍⪵☁⧉ᙹၰ⚍ᙹ✚ᖒ

ᔍᬊࡽ ᜽ഭ۵ Ğʑࠥ ᮹ᱶᇡḡᩎ᮹ ᱩ☁ᔍ໕ᇡᨱᕽ ₥≉ࡽ

⠙ษ⣮⪵☁ಽFig. 4᪡Table 1ᮡ᜽ഭᨱݡ⦽ʑᅙྜྷᖒᝅ⨹ᮥ

ᝅ᜽⦽đŝᯕ໑, ⠙ษ⣮⪵☁۵☖ᯝᇥඹᔢSP-SM ᜽ഭᯕ݅.ੱ⦽

⚍ᙹᝅ⨹đŝ, ᯝၹᱢᯙ⣮⪵☁ᨱݡ⦽⚍ᙹĥᙹ᮹ჵ᭥ෝⅩŝ⦹

ḡ۵ ᦫ۵ äᮝಽ ❱݉ࡹᨩ݅.

ᇩ⡍⪵⧉ᙹ✚ᖒłᖁ᜽⨹ᮥᙹ⧪⦹ᩍ⠙ษ⣮⪵☁ᨱݡ⦽Õ

᳑ŝᱶ᮹⧉ᙹ✚ᖒłᖁᮥ⫮ा⦹ᩡŁ⯂ᙹಆŝℕᱢ⧉ᙹእᄡ⪵

ෝᱶప⪵⦹ʑ᭥⦹ᩍFredlund and Xing (1994)᮹እᖁ⩶3ĥᙹ

฿∅⪵᜾ᮥ ᱢᬊ⦹ᩡ݅.

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Fig. 4. Grain Size Distribution of Gneiss Weathered Soils

Table 1. Properties of Soils

Soil particle density (g/cm

³

) 2.676

Passing rate, #200 (%) 3.7

Plastic limit (%) N.P

Cohesion, c (kPa) 4.9

Angle of internal friction, φ ' (°) 34.8

Fig. 5. SWCC of Gneiss Weathered Soils

Fig. 6. Unsaturated Permeability of Gneiss Weathered Soils

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ᩍʑᕽ,

ľ

:ℕᱢ⧉ᙹእ,

ľ

Ƒ:⡍⪵᜽ℕᱢ⧉ᙹእ, a: Ŗʑ⧉᯦⊹᪡

šಉࡽĥᙹ, n: ⧉ᙹ✚ᖒłᖁ᮹ʑᬙʑ᪡šĥ⦹۵łᖁĥᙹ, m:

᯵ඹ⧉ᙹእ᪡šĥ⦹۵łᖁĥᙹᯕ݅. ੱ⦽, :ᅕᱶĥᙹᯕŁ, : ᯵ඹℕᱢ⧉ᙹእ

ľ

_Ɛ: ݡ᮲⦹۵ ⯂ᙹಆᮥ ᮹ၙ⦽݅.

Fig. 5۵⫮ाࡽ⯂ᙹಆŝℕᱢ⧉ᙹእ᮹⧉ᙹ✚ᖒšĥෝᅕᯕŁ

ᯩ݅. ᩍʑᕽŖʑ⧉᯦⊹۵4.80kPaᯕ໑, sa۵7.41, nᮡ1.90, əญŁmᮡ0.50a᨜ᨕᲭ݅. Fig. 6ᮡ⠙ษ⣮⪵☁᮹ᇩ⡍⪵☁

⚍ᙹĥᙹෝᅕᯕŁᯩ۵ߑFredlund et al. (1994)ᨱ᮹⧕ᱽᦩࡽ

᜾(6)ෝ ᔍᬊ⦹ᩍ eᱲᱢᮝಽ ⇵ᱶ⦹ᩡ݅.

(6)

ᩍʑᕽkr:⡍⪵᜽⚍ᙹĥᙹᨱݡ⦽ᇩ⡍⪵᜽⚍ᙹĥᙹᨱݡ⦽

እ, b: 1000000ᨱ ᯱᩑಽəෝ≉⦽ s, 쩇’: ᜾(4)ෝ ༉š⯂ᙹಆ

쩗ᨱ ݡ⧕ ၙᇥ⦽ sᯕ݅, 쩗aev: Ŗʑ⧉᯦s ᯕ݅.

əฝ᮹đŝಽᇡ░, ⯂ᙹಆᯕ᷾a⧉ᨱ঑௝ᇩ⡍⪵☁⚍ᙹĥᙹ a ԏᦥḡŁ ᯩᮭᮥ ᅝ ᙹ ᯩ݅.

4. ᇩ⡍⪵☁⣮⪵ᔍ໕᮹ᦩᱶᖒ⠪a

ᦩᱶᖒ ⠪aෝ ᭥⦹ᩍ ࢱ aḡ Ğᬑಽ ӹ٥ᨩ۵ߑ ᇩ⡍⪵☁

ᔍ໕᮹ᖁ⧪vᬑ⬉ŝෝ᦭ᦥᅕŁI.D.F ႊჶ᮹vᬑᔍᔢᮥᱢᬊ

⦹ᩍᇩ⡍⪵☁ᔍ໕᮹Ⅹʑ⯂ᙹಆᄡ⪵ᨱ঑ෙᔍ໕᮹ᦩᱥᖒᮥ

⠪a⦹ᩡ݅. ࢹṙಽ۵ ᔍ໕ ❭ƕ᮹ ᬱᯙᯙ vᬑᔍᔢᮥ ࢱ aḡ

ႊ᜾, ᷪI.D.F ႊჶŝHuff ႊჶᮥᱢᬊ⦹ᩍvᬑᔍᔢᯕᔍ໕᮹

ᦩᱥᖒᨱ ၙ⊹۵ ᩢ⨆ᨱ ݡ⧕ ᔕ⠕ᅕᦹ݅.

(5)

Fig. 7. Model View of Infinite Soil Slope

Table 2. Increase in Apparent Friction Angle due to Suction ( φ )

^b

Initial suction 5 kPa 10 kPa 25 kPa

φ

b

31.6° 27.7° 17.3°

in Gangneung

4.1 ැজ୺Ս

⧕ᕾݡᔢᮥFig. 7ŝzᯕ݉⊖2₉ᬱྕ⦽☁ᔍᔍ໕ᮝಽ1:1.2᮹

Ğᔍෝaḡ໑⩶ᔢᮡʙᯕ38m, ׳ᯕ25mಽĞᔍǍeᮡʙᯕ۵

18.0m, ׳ᯕ15.0mಽ⦹ᩡ݅. ḡ⦹ᙹ᭥۵⋉⚍Ñ࠺ᨱᩢ⨆ᮥ↽ݡ

⦽႑ᱽ⦹ʑ᭥⧕⦹ᇡᨱᕽḡ⦹9.0mᨱ᳕ᰍ⦹۵äᮝಽaᱶ⦹ᩡ

݅. ੱ⦽⠙ษ☁᮹ᇩ⡍⪵⧉ᙹ✚ᖒłᖁŝ⚍ᙹĥᙹ, əญŁvࠥᱶ ᙹsॅᮥḡၹྜྷᖒ⊹ಽᱢᬊ⦹ᩡ݅. ᩍʑᕽᔍ໕ḡၹ᮹݉᭥ᵲప

ᮡ 16.7kN/m³ಽ ⦹ᩡ݅.

ᇩ⡍⪵ᔢ┽ᔍ໕ᦩᱶ⧕ᕾᮥ᭥⦽ḡၹ᮹vࠥᱶᙹ۵⡍⪵ᔢ┽

ᔝ⇶ᦶ⇶ᝅ⨹(CU-test)ᮥᝅ᜽⦽⬥⯂ᙹಆ᷾aᨱ᮹⦽ԕᇡษ ₑb, ෝ⫮ा⦹ʑ᭥⧕Vanapalli et al. (1996)ᨱ᮹⧕ᱽᦩࡽ

ᱥ݉vࠥ᜾ᨱᕽ êᅕʑ ᱱ₊ಆ⧎ᨱᕽ᮹ ᜾(6)ŝ zᮡ šĥ᜾ᮥ

⪽ᬊ⦹ᩍ⇵ᱶ⦹ᩡ݅. Table 2۵⠙ษ⣮⪵☁᮹⯂ᙹಆ᷾aᨱ᮹⦽

ԕᇡษₑb, sᮥ ӹ┡ԕᨩ݅.

(6)

ᩍʑᕽ, : ༉š⯂ᙹಆᨱ᮹⦽ԕᇡษₑb(°),

ľ

:ℕᱢ⧉ᙹእ,

ľ

_Ɛ: ᯵ඹℕᱢ⧉ᙹእ, : ᮁ⬉ ԕᇡษₑb(°)ᯕ݅.

Huff ႊჶ᮹ Ğᬑ, ┽⣮ᮝಽ ᯙ⦽ vᬑ᮹ ᩢ⨆ᯕ ⓑ vᬱࠥ

v෪ḡᩎ᮹vᬑᔍᔢᨱݡ⦽ ᇥ᭥ᄥྕ₉ᬱ٥ałᖁᮡݡ⢽ᱢ ᮝಽ 2ᇥ᭥ ྕ₉ᬱ ⪶ශ 50%ෝ ᔍᬊ⦹ᩡ݅. Fig. 8ᨱᕽ۵ ᜾

(3)ᮥ ᯕᬊ⦹ᩍv෪ḡᩎ᮹ⅾvᬑ᜽eᮥ100%ಽ⦹Ł, 10}

Ǎeᮝಽ ӹ٥ᨕ ⅾ vᬑ᮹ b 10%ᨱ ⧕ݚ⦹۵ ᜽eǍԕᨱᕽ ᮹ vᬑෝ ⅾ vᬑపᨱ ݡ⦽ %ෝ ӹ┡ԕŁ ᯩ݅. ᩍʑᕽ, C0, C₁, C₂,ⲷ, C6ᮡ 1.12E-02, 8.09E-01, -8.01E-02, 5.31E-03, -1.10E-04, 9.45E-07, -2.96E-09ᯕbbᱢᬊࡹᨩ݅. Fig. 9ᨱᕽ

b ᇥ᭥ษ݅ 50%᮹ ྕ₉ᬱ ⪶ශᮡ ⧕ݚᇥ᭥᮹ ⪙ᬑ᮹ ᱩၹᮥ

Ⅹŝ⦹۵٥avᬑ᧲ᔢᮥ᮹ၙ⦹໑, 90%۵⪙ᬑ᮹10% ੱ۵

əᯕ⦹aၽᔾ⧁ᇥ⡍ෝ᮹ၙ⦽݅. ঑௝ᕽ, bᇥ᭥ᄥಽၽᔾ⪶ශ

10~90%᮹9aḡᇥ⡍⩶┽ᨱᕽ℉ࢱvᬑa⧕ݚᇥ᭥᮹ᵲᝍᨱ

᭥⊹⦹۵50%ෝᖁ┾⦹ᩡ݅. ᯕ۵ǎԕvᬑᖅĥᨱᕽᵝಽ₥┾ࡹ

Ł ᯩ۵ ၽᔾ⪶ශᯕ݅ (MOCT 2000).

ᅙᩑǍ᮹ᔍ໕ᦩᱶ⧕ᕾᨱᕽ۵ݡ⢽ᱢᮝಽHuff ႊჶ᮹2ᇥ᭥

ෝᱢᬊ⦹ᩡŁ, ⧕ᕾ᜽ᇩ⡍⪵⋉⚍ʫᯕ⇵ᱶŝᔍ໕ᦩᱶ⧕ᕾᮥ

᭥⦹ᩍ Bishop᮹ e⠙ჶᮥ ᱢᬊ⦹ᩡ݅.

(6)

Fig. 10. Used Rainfall Pattern in Analysis (I.D.F Method Case)

Table 3. Condition for I.D.F. Method Case

SWCC Drying curve

Initial suction 5, 10, 25 kPa

Rainfall Pattern

I.D.F Method

Gangneung (527.6mm × 2=1055.2mm) (200 years Frequency, Rainfall duration: 96 hours)

Fig. 11. Change in Factor of Safety under Various Initial Suction in Slope

(a) Initial Suction at 5kPa

(b) Initial Suction at 10kPa

(c) Initial Suction at 25kPa

rainfall duration

4.2 ొ׆ใ৤ߚ઩ݗࠛॷ࡟ଭੲୢনඌԧ

4.2.1 ැজ୺Ս

ᖁ⧪vᬑ⬉ŝෝӹ┡ԕ۵Ⅹʑ⯂ᙹಆᨱ঑ෙᦩᱥᖒᮥ⠪a

⦹ʑ᭥⧕vᬑᔍᔢᮡI.D.F ႊჶᮥᔍᬊ⦹ᩡ݅. vᬑvࠥ۵vᬱ

ࠥv෪ḡᩎ᮹200֥ኩࠥ48᜽e᮹vᬑ᳑Õᮥᱢᬊ⦹ᩍ, ᯕෝ

96᜽eᮝಽᩑᰆ⦹۵ႊ᜾ᮝಽᦩᱶ⧕ᕾᮥᝅ᜽⦹ᩡ݅. ᯕ᪡zᮡ

᳑Õᮡ⠙ษ⣮⪵☁᮹⡍⪵⚍ᙹĥᙹᅕ݅׳ᮡvᬑvࠥෝᔍᬊ⧉ᮝ

ᱶᨱᨕਅᩢ⨆ᮥၙ⊹۵ḡ᦭ᦥᅕŁᯱᙹᇥ✚ᖒłᖁᨱᕽ⡍⪵ࠥ

ᨱ঑௝⯂ᙹಆ᮹ᄡ⪵aⓑǍeᮥ ᔢᱶ⦹ᩡ݅. ঑௝ᕽⅩʑ⯂ᙹಆ

5, 10, 25 kPaᯕᱢᬊࡹᨩŁ, ⧕ᕾᨱᔍᬊࡽvᬑᔍᔢᮡFig. 10ŝ

z݅. ⧕ᕾ᳑ÕᮡTable 3ŝzᮡߑ⧕ᕾ᜽eᮡⅾ96᜽eᮝಽ

⦹ᩍ0.1, 0.5, 1, 2, 3, 5, 10, 24, 48, 72, 96 ⅾ11݉ĥᨱÙℱ

ᔍ໕ᨱ ݡ⦽ ᦩᱥᮉ ᄡ⪵ sᮥ ⫮ा⦹ᩡ݅.

(7)

Fig. 13. Adopted Rainfall Pattern for Gangneung Case

Table 4. Condition for Huff Method Case

SWCC Drying curve

Initial suction 10 kPa

Rainfall Pattern

Huff Method - 2th

Gangneung (527.6mm × 2 = 1055.2mm) (200 years Frequency, Rainfall duration: 96 hours)

10kPa (Huff Method: 2

^nd

and 96 Hours Rainfall)

Fig. 15. Factor of Safety under Initial Suction at 10kPa (Huff Method: 2

^nd

and 96 Hours Rainfall)

⩶ᖒ᭥⊹aၵѭʑভྙᯕ݅. ᯕ్⦽ḡၹ᮹ʫᯕᄥ⯂ᙹಆᄡ⪵۵

Fig. 12ᨱᕽ⪶ᯙ⧁ᙹᯩ۵ߑⅩʑ⯂ᙹಆᯕ׳ᦥḩᙹಾᔍ໕᮹

⡍⪵ݡ ⩶ᖒ᜽eᯕ ܇∑ḡŁ ᯩᮭᮥ ᦭ ᙹ ᯩ݅.

঑௝ᕽ, ḡၹ᮹Ⅹʑ⯂ᙹಆᮡvᬑ᜽ᔍ໕᮹ᦩᱥᮉᄡ⪵ᨱ

ⓑ ᩢ⨆ᮥၙ⊹Ł ᯩᮝ໑ Ⅹʑ⯂ᙹಆᮥᮁḡ⦹۵ äᯕ vᬑ᜽

ᔍ໕❭ƕෝ⬉ŝᱢᯙႊჶᯥᮥ᦭ᙹᯩ݅. ঑௝ᕽḡၹ᮹Ⅹʑ⯂ᙹ ಆᮁḡෝ᭥⧕ᕽ۵ᔍ໕ᨱᕽ᮹⢽໕႑ᙹ᮹ᩎ⧁ᯕๅᬑᵲ᫵⦹݅

Ł ❱݉ࡽ݅.

(8)

rainfall duration under Initial Suction at 10kPa (Huff Method: 2

^nd

)

Fig. 17. Change in Factor of Safety based on Rainfall Pattern

ಽaᱶ⦹Łvᬑᔍᔢᨱݡ⦽⧕ᕾᮥᙹ⧪⦹ᩡ݅. ✚⯩vᬑᔍᔢ

ᮥđᱶ⦹۵ߑᯩᨕ໦⪶⦽ᦩᱥᮉእƱෝ᭥⧕vᬑḡᗮ᜽eᮥ

96᜽eʭḡḡᩑ᜽┅۵ŝᱶᯕ⦥᫵⦹ᩍᅙᩑǍᨱᕽ۵48᜽e

527.6mm᮹vᬑ᳑Õᮥ96᜽e1055.2mm᮹vᬑపᮝಽ᳑ᱶ⦹

ᩡ݅. ᯕ᪡zᮡvᬑᔍᔢᨱݡ⦽᳑ÕᮡFig. 13ᨱᕽӹ┡ԕᨩ݅.

4.3.2 ැজէր

Fig. 14᪡15ᨱᕽᇩ⡍⪵☁ᔍ໕(Ⅹʑ⯂ᙹಆ10kPa)ᨱݡ⦽

Huffႊჶ2ᇥ᭥vᬑᔍᔢᮥᱢᬊ⦽⬥, 96᜽eᯕĞŝࡽ⋉⚍⧕ᕾ

đŝ᪡↽᳦❭ƕ݉໕ᮥᅕᯕŁᯩ݅. 96᜽e⬥᮹ᦩᱥᮉᮡ1.299

ෝᅕᯕŁᯩᮝ໑, ᯕđŝ۵Fig. 11ᨱᕽ᮹đŝᨱᕽࠥᯕၙӹ┡ԕ ᨩ݅. ⦽⠙, Fig. 13ᨱᕽᅕᯕॐvᬑపᯕ40᜽eᮥʑᱱᮝಽqᗭ

⦹Ł ᯩʑ ভྙᨱ, Fig. 16ᨱᕽ᪡ zᯕ vᬑḡᗮ᜽e 96᜽eᨱ

ᔍ໕᮹⢽⊖ᇡ᭥aᱱᱱᮭ᮹eɚᙹᦶ, ʫᯕᄥ⯂ᙹಆᯕᔢ᜚⦹

໑ᇩ⡍⪵ᔢ┽ಽᱥ⪹ࡹŁᯩᮭᮥ᦭ᙹᯩ݅. đǎ, I.D.F ႊჶ ŝHuff ႊჶ᮹ᱢᬊࡽvᬑᔍᔢᯕFig. 13ŝzᯕ݅ෙᮁ⩶ᮝಽ

ᱢᬊࡹʑᨱ⋉⚍ၰᦩᱶ⧕ᕾđŝaᔢᯕ⦹íࠥ⇽ࡽ݅Ł❱݉ࡽ

݅. vᬑḡᗮ᜽e72᜽eᯕ⬥ᇡ░vᬑᔍᔢᨱ঑௝I.D.F ႊჶᮡ

᜽eᨱ঑ෙ qᗭෝ ӹ┡ԕᨩŁ, Huff ႊჶᮡ ᦩᱥᮉ᮹᷾aෝ

ӹ┡ԕŁᯩ݅(Fig. 17). ᷪHuff ႊჶ᮹Ğᬑᝅᱽvᬑ᪡zᮡ

ᵝʑ(2ᇥ᭥)ᵲ⦹ӹಽᱢᬊࢉᮝಽ៉72᜽eᯕ⬥ᨱᔍ໕᮹ᦩᱥᮉ ᯕ ⫭ᅖࡹŁ ᯩᮭᮥ ᦭ ᙹ ᯩ݅.

঑௝ᕽ, I.D.F ႊ᜾ŝzᮡᯝᱶ⦽vᬑᔍᔢ᮹ᱢᬊᮡĥᗮᱢᯙ

ᦩᱥᮉ qᗭෝ ᮁࠥ⧉ᮝಽ៉ ᝅᱽ ᔍ໕ Ñ࠺᮹ ᦩᱥᮉ ᄡ⪵ෝ

ӹ┡ԕḡ༜⦹Łᯩᮝ໑, ᯕ۵ᝅᱽᔍ໕ᖅĥ᜽ᦩᱥ⊂đŝෝ

ࠥ⇽⧁äᮝಽ⇵ᱶࡽ݅. ⦽⠙, Huff 2ᇥ᭥ᨱݡ⦽ᦩᱥᮉᄡ⪵

᧲ᔢŝ ʫᯕᄥ ⯂ᙹಆ ᄡ⪵ෝ ☖⧕, ⩥ᰆᔍ໕᮹ ᖅĥ᪡ ᩩ⊂ᨱ

ᯩᨕHuff ႊჶŝzᮡᝅᱽvᬑᔍᔢᮥᱢᬊ⧉ᮝಽ៉ḡᩎᝅᱶᮥ

ၹᩢ⦽ ᔍ໕᮹ Ñ࠺ᮥ ❭ᦦ⧁ ᙹ ᯩ݅.

5. đು

ᅙםྙᨱᕽ۵ᇩ⡍⪵᳑Õᨱᕽvᬑᔍᔢᨱ঑ෙᔍ໕ᦩᱶᖒᮥ

⠪a⦹ᩡ۵ߑ đುᮡ ᱶญ⦹໕ ݅ᮭŝ z݅.

(1) ᇩ⡍⪵ᔍ໕ᨱᕽⅩʑ⯂ᙹಆᨱ঑ෙᦩᱶ⧕ᕾᨱᕽⅩʑ⯂ᙹಆ ᯕ᷾a⧁ᙹಾᔍ໕᮹ᦩᱥᮉᮡ᷾a⧉ᮥ⪶ᯙ⧁ᙹᯩᨩ݅.

ᯕ్⦽đŝ۵Ⅹʑ⯂ᙹಆᯕ׳ᮥᙹಾ, ⡍⪵ࡹʑʭḡ᮹᜽e ᮹ḡᩑŝ׳ᮡ⯂ᙹಆᨱ᮹⦽ḡၹ᮹ᱥ݉vࠥ᮹᷾aᨱᩢ⨆

ᮥ ၼʑ ভྙᯕ௝ ⧁ ᙹ ᯩ݅.

(2) I.D.F᪡Huff ႊჶᨱ঑ෙᇩ⡍⪵ᔍ໕ᦩᱥᮉᄡ⪵ෝᔕ⠕ᅙ

đŝ, ᜽eᇥ⡍ෝ Łಅ⦽ Huff ႊჶᮡ ᔍ໕ ᦩᱥᮉ ᄡ⪵ෝ

ᮁᩑ⦹íӹ┡ԕŁᯩᮭᮥ᦭ᙹᯩᨩ݅. ঑௝ᕽᯝᱶ⦽vᬑᔍ ᔢŝ޵ᇩᨕ⩥ᰆᔍ໕᮹ᖅĥᨱᯩᨕHuff ႊჶŝzᮡᝅᱽ

vᬑᔍᔢᮥᱢᬊ⧉ᮝಽ៉əḡᩎᝅᱶᨱ฿۵ᔍ໕᮹ᦩᱥᮉᮥ

ᄲ⧪⦹ᩍࠥ⇽⧁ᙹᯩᨕᅕ݅⬉ŝᱢᯙᇥᕾᯕa܆⦹ญ௝

❱݉ࡽ݅.

(3) ⇵aᱢᯙᩑǍෝ☖⦹ᩍ᜽eᇥ⡍ෝ⪽ᬊ⦽vᬑ➉▕ŝ݅᧲⦽

ḡᩎᮥݡᔢᮝಽᇩ⡍⪵ᔢ┽ᔍ໕ᨱᕽᔍ໕ḡၹŝvᬑ᳑Õŝ ᮹ᔢ⪙᯲ᬊᮥ⠪aaa܆⦹໑ᯕෝ☖⦹ᩍᅕ݅ᝅᱽᱢᯙ

ႊჶᮥ ᱽ᜽⧁ ᙹ ᯩᮝญ௝ ʑݡ⦽݅.

qᔍ᮹ɡ

ᅙ םྙᮡ 2011֥ ᱶᇡ(Ʊᮂŝ⦺ʑᚁᇡ)᮹ ᰍᬱᮝಽ ⦽ǎᩑ Ǎᰍ݉᮹ḡᬱᮥၼᦥᙹ⧪ࡽᩑǍᯥ(NRF-2010-616-D00098).

(9)

No. 3, pp. 533-46.

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GEO-SLOPE International Ltd. (2004). “Computer program SLOPE/W for slope analysis.” User’s guide, Calgary, Alta, Canada.

Huff, F.A. (1967). “Time distribution of rainfall in heavy storms.”

Water Resources Research, Vol. 3, No. 4, pp. 1007-1019.

Huff, F. A. (1970). “Time distribution characteristics of rainfall rates.” Water Resources Research, Vol. 6, No. 2, pp. 447-454.

Kim, J., Park, S. W., Jeong, S. and Yoo, J. (2002). “A study of stability analysis on unsaturated weathered slopes based on rainfall-induced wetting.” Journal of Korean Geotechnical So- ciety, Vol. 18, No. 2, pp. 123-136 (in Korean).

Kim, J., Jeong, S., Park, S., and Sharma, J. (2004). “Influence of rainfall-induced wetting on the stability of slopes in weathered soils.” Engineering Geology, Vol. 75, No. 3-4, pp. 251-262.

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강우사상의 영향을 고려한 불포화 풍화사면의 안정성

[email protected])

Received October 7 2012, Revised October 29 2012, Accepted April 1 2013

Copyright ⵑ 2013 by the Korean Society of Civil Engineers

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)

ABSTRACT

Key words : Rainfall pattern, I.D.F method, Huff method, Slope stability, Initial suction

Ⅹಾ

ᔍ໕ᦩᱶ⧕ᕾ᜽, ᔍ໕❭ƕ᮹ᵝᬱᯙᯙvᬑᔍᔢ᮹⩥ᝅᱢᱲ༊ᮥ᭥⦹ᩍᅙᩑǍᨱᕽ۵݅ᮭࢱaḡႊჶᮥ₥┾⦹ᩡ݅. ⦹ӹ۵᜽eᨱ঑ෙ

vᬑపᄡ⪵᮹ᩢ⨆ᮥྕ᜽⦽ʑ᳕᮹ᖅĥvᬑႊ᜾ᯙI.D.F(Intensity-Duration-Frequency)łᖁᮥᯕᬊ⦹۵ႊჶᯕ໑, ݅ෙ⦹ӹ۵᜽e᮹

ᩢ⨆ᮥŁಅ⦹ᩍvᬑᔍᔢᮥ⢽⩥⦽Huff ႊჶᯕ݅. ຝᱡI.D.F ႊჶ᮹vᬑᔍᔢᮥᱢᬊ⦹ᩍᖁ⧪vᬑ⬉ŝෝӹ┡ԕ۵Ⅹʑ⯂ᙹಆ᮹ᄡ⪵ᨱ

঑ෙᔍ໕᮹ᦩᱥᮉ᮹ᄡ⪵ෝ᦭ᦥᅕᦹ݅. ੱ⦽, ࢱvᬑᔍᔢ᮹ႊ᜾ᮥᱢᬊ⦹ᩍvᬑᔍᔢᯕᔍ໕᮹ᦩᱥᮉᄡ⪵ᨱၙ⊹۵ᩢ⨆ᮥȽ໦⦹Łᯱ

⦹ᩡ݅. əđŝ, Huff ႊჶ᮹vᬑᔍᔢᯕI.D.F ႊჶᅕ݅޵⩥ᝅᱢᮝಽᔍ໕᮹ᦩᱥᖒ⠪aaᯕ൉ᨕḩᙹᯩᮭᮥ⪶ᯙ⧁ᙹᯩᨩ݅.

áᔪᨕ vᬑᔍᔢ, I.D.F ႊჶ, Huff ႊჶ, ᔍ໕ᦩᱶ, Ⅹʑ⯂ᙹಆ

1. ᕽು

Fig. 1. Conceptual View of Unsaturated Slope Failure due to Rainfall

Fig. 2. Definition of Average Maximum Rainfall Intensity

2. vᬑᔍᔢ

2.1 I.D.F ࢺ࣑

2.2 Huff ࢺ࣑

Fig. 3. Time Distribution of Rainfall Pattern by Huff Method

3. ᇩ⡍⪵☁⧉ᙹၰ⚍ᙹ✚ᖒ

Fig. 4. Grain Size Distribution of Gneiss Weathered Soils

Table 1. Properties of Soils

Soil particle density (g/cm

) 2.676

Passing rate, #200 (%) 3.7

Plastic limit (%) N.P

Cohesion, c (kPa) 4.9

Angle of internal friction, φ ' (°) 34.8

Fig. 5. SWCC of Gneiss Weathered Soils

Fig. 6. Unsaturated Permeability of Gneiss Weathered Soils

ľ

ľ

ľ

4. ᇩ⡍⪵☁⣮⪵ᔍ໕᮹ᦩᱶᖒ⠪a

Fig. 7. Model View of Infinite Soil Slope

Table 2. Increase in Apparent Friction Angle due to Suction ( φ )

Initial suction 5 kPa 10 kPa 25 kPa

φ

31.6° 27.7° 17.3°

in Gangneung

4.1 ැজ୺Ս

ľ

ľ

Fig. 10. Used Rainfall Pattern in Analysis (I.D.F Method Case)

Table 3. Condition for I.D.F. Method Case

Contents

SWCC Drying curve

Initial suction 5, 10, 25 kPa

Rainfall Pattern

I.D.F Method

Gangneung (527.6mm × 2=1055.2mm) (200 years Frequency, Rainfall duration: 96 hours)

Fig. 11. Change in Factor of Safety under Various Initial Suction in Slope

(a) Initial Suction at 5kPa

(b) Initial Suction at 10kPa

(c) Initial Suction at 25kPa

rainfall duration

4.2 ొ׆ใ৤ߚ઩ݗࠛॷ࡟ଭੲୢনඌԧ

Fig. 13. Adopted Rainfall Pattern for Gangneung Case

Table 4. Condition for Huff Method Case

Contents

SWCC Drying curve

Initial suction 10 kPa

Rainfall Pattern

Huff Method - 2th

Gangneung (527.6mm × 2 = 1055.2mm) (200 years Frequency, Rainfall duration: 96 hours)

10kPa (Huff Method: 2

and 96 Hours Rainfall)

Fig. 15. Factor of Safety under Initial Suction at 10kPa (Huff Method: 2

and 96 Hours Rainfall)

rainfall duration under Initial Suction at 10kPa (Huff Method: 2

)

Fig. 17. Change in Factor of Safety based on Rainfall Pattern

5. đು

qᔍ᮹ɡ

No. 3, pp. 533-46.

GEO-SLOPE International Ltd. (2004). “Computer program SEEP/W for finite element seepage analysis.” User's guide, Calgary, Alta, Canada.

GEO-SLOPE International Ltd. (2004). “Computer program SLOPE/W for slope analysis.” User’s guide, Calgary, Alta, Canada.

Huff, F.A. (1967). “Time distribution of rainfall in heavy storms.”

áᔪᨕ vᬑᔍᔢ, I.D.F ႊჶ, Huff ႊჶ, ᔍ໕ᦩᱶ, Ⅹʑ⯂ᙹಆ