/* (,**/) - +3/,*+,**. 3 +,,**. +* +-,**/. 3 Asama Explosion of September +st,,**. On the Damage to Glass Windows and Estimation of Explosion Energy Akihiko YOKOO,, Fukashi MAENO and Hiromitsu TANIGUCHI At,* : *, JST on September +st,,**., Asama volcano erupted and produced a strong air wave (,*/ Pa at 1.0 km away from the summit). The wave induced some damages to glass windows in buildings located within about ++ km of the summit. The detailed situations about these damages are reported in this paper. The explosion energy of this eruption and diameter of crater are estimated to be +.. +* +,,., +* +, J and about 1/ m, respectively, based on the assumption that scaling laws obtained by charge explosion experiments were applicable to the case of explosive volcanic eruption. Key words : Asama volcano, air wave, glass breakage, explosion energy +,,/02 m 3 +3-* ; +33+ +3/* Sakuma (+3/+) +31- (+31-) 32* 2/12 0 - Institute of Mineralogy, Petrology, and Economic Geology, Graduate School of Science, Tohoku University, 0 -, Aramaki-Aza-Aoba, Aoba-ku, Sendai 32* 2/12, Japan. : 23+ +.+3 +1,, +3 Present Address: Sakurajima Volcano Research Center, Disaster Prevention Research Institute, Kyoto (Baker et al., +32-) Taniguchi (+33-) (,***),**. 3 University, +1,, +3, Sakurajima-Yokoyamacho, Kagoshima 23+ +.+3, Japan. 32* 2/10.+ Center for Northeast Asian Studies, Tohoku University,.+, Kawauchi, Aoba-ku, Sendai 32* 2/10, Japan. Corresponding Author: Akihiko Yokoo e-mail: yokoo@svo.dpri.kyoto-u.ac.jp
¹ º:»¼ 196 +! "#$%& ' 3 + $()*+,-. /0 1 z{ } ^'_1 567 ~ C]^'_abc$ `- d $ (Fig. +) : ', `A D d $ 8,*,, ( 0-., Pa), 1.0 km ] O,ῌ ῑ ῐ,**. ΐ 3 + ῒ,*/ Pa 1 f < ],**. 2 3 +,* 3 *, 4 567879 :! 567 N$ +0 $ -/* bz ; <' 7= >? @ ABCD! $ '^$ FG 7EFGHIJK$L'MN 7OP 7 QRC 8 PPI! $ %MNo D 1 3 + $ ST 8 +U+*/ t VW XY `,**/d1! o ª bu $ Z[\C]^'_ `abc,**.d1 e$f 3 gh 7EFG y«'z 8 3* km V ] m 8 :i jk ^l m nopqc]_ r `st X_1 3 + $ 8 ±Z²r! u v,**.d,**. 2 +* wxy5678z ³ FY $ +32, 2 $y$ `µ +32,d Fig. +. Disaster distributions around the Asama Volcano by the September +st eruption. Six places su#ered from the air wave ; damage to glass windows (open circles) and others (closed circles). Three squares represent the volcano-acoustic stations equipped with a low-frequency microphone by the Japan Meterological Agency, and the star shows the location where 1 ballistic rocks were discovered by our investigation.
,**. 3 + 197 +31- +31-3 2,.1 km (Fig. +) / +* cm 1-0 -1/ g (SiO, /3.1 0*.+ wt. ). km,**.,**- 0 +*,**. 3 - +.0 km + m - - + ( p ) (I p (t) dt) (Baker et al., +32-) (Table +) (Taniguchi, +33-) (Saito et al.,,**+) Table + + -, 3 + 3 + -, +,* km + ++ km + 0 km + 1./ km (Fig. +) -, +. km (Fig. +) + + /* cm (Fig.,a) Table +. Relationship between the overpressure and damage to glass windows.
<uvw $` x l4»¼ 198 ) L-._ +,*ῌ+/* cm '( `* /a% b$ BTU ++** mm :11* mm:- mm c1 S *, " -.( d&e 0*/ LP < 0f 1 631 9, g'h 9 '( (Fig.,b) -ῌ,ῌ- $i M,2 j Yk"h34 2 - ; 5 _. km, Fig. +> 65.?@ABCD O7 +_ 0 cm 81l 9m :h (Fig.,c) BTU +/./ mm:2** mm:0.2 mm?@abcd_ I ; E FnCop DqrprGstpu c1 <= >v,?% 9 w8% xy@ z)31 A & 9m :h 01c -]7 3 0 cm 2 BC D{C G &?@ABCD # D 51 9 z)31 ; +}Ej~F G H> -ῌ,ῌ. 2 Fig.,. Photos of (a) glass breakage at the Asama Volcano Museum taken by Kyodo News, (b) a view from a broken window at Tashiro Primary School and (c) a glass crack at the Asama Memory House taken by M. Enomoto. % I <= #MJ KL M 51 g *, ;N +,,// m> O >v 3JP +,, 9 3 #M & 9m QR% S- 3 % % T w8 Z & JP, 9 ' UVW )c ;Sakuma, +3/+ ; XY KB Z[ \M, ] +33*> +3,3 ^ Fig.,a! " # $ % &' () * " +,, " -. -*/ 01 2 3 Uc%S 4 5% 6ῌ, 78, -3 9 3 #M *,6. JKL 2! % '_ 51 ;&`] a +3-*>, 3 `* d&e ++ km KL Yk"`* J 3 Fbb x@ & 9m z)31,*** mm:3** mm:/ mm ;! < =5> ; %>?@ABCD EF DG@H. I 51 $i -ῌ,ῌ, JKL G c JPd - e% % % f,d M,# M4 ++ km 2 % M @ªG g«51 M, m ; ) (Fig. +) - NO LP + N QR +! #h/ai > % "QR S' +! #M$ M,B X k b z)31 %&% % ; %> BTU +*0* mm:20* mm:- mm?@abcd EF DG@H I 51 V,ῌ- '( % +/ cm:,* cm '( )WX 3 /* cm Y Z*1 QR+, 51 [\ Y ]Z-^ Ki j ;Taniguchi, +33- ; l4 m,***> e `\f, ± ² ; ³Gqpun> M,#M op q 'µ 3 + r M,#M f, @ªG s 3 + r#m # F t9 0¹ º
,**. 3 + 199 *.,**. + +* / t,**. +/** +0** kg m - 0 +*. 1 +*. m - 3 +0 SAR +** m:,**. 3 + D +** m d m V m - V pdd, +, (+) 0 +*. 1 +*. m - D d Goto et al. (,**+) D E exp J logd *.-, loge exp,.*0 (,) (Fig. -a) D d m J + - d E exp + - Fig. -b *.**. m J + - (,) 1* +** m +.0 +* +,..1 +* +, J Baker et al. (+32-) TNT P Pa l m J + - l m + - +*, +* - Pa l,.* P *.30 *.*1 (-) Baker et al. (+32-) Figure,./ O (,*/ Pa) l +./, m J + - O 1.0 km 3 + (10**/+./,) - +.- +* ++ J E exp (Fig. - Fig. -. The relationships between the crater diameter (D ; m) and (a) : Explosion energy (E exp ; J) calculated using eq. (,), (b) : scaled depth of explosion(d ;m/j +/- ) under the assumption of crater s volume; V 0.* +*. m - and 1.* +*. m -, and (c) : ratio of energy partition for blast from explosionenergy (e blast). Dashed lines in (c) are derived by applying the results from field explosionexperiments (eq. (.)). See text in details. a) +.- +* ++ J E exp (Goto et al.,,**+) e blast d * d *.*+ e blast exp *../ 1** d (.) 3 + D
200 d (Fig. -b) e blast 0 +*. 1 +*. m - Fig. -c D V D d d (Fig. -b) (.) e blast (Fig. -a) e blast Fig. -c 3 + 3 + 1. 11 m +.. +* +,,., +* +, J (Fig. -a) (+).,./ m *.**-. *.**-/ m J + - (Fig. -b) E exp d l w kg J + - (Fig..) Fig.. *.**- *.**. m J + -,*** (*.**-. *.**-/ m/j +/- ) *.*. m J + - E exp (+.. +* +,,., +* +, J : Fig. -a) + - 3 +../ / km..1 +* 1 J +* g Fig..,.2 +* / kg J + -,.2 +* / E exp *.- + - kg,.1 km Fig... Relationships among scaled distance (l ;m/ J +/- ), scaled depth (d ;m/j +/- ), and scaled weight of ballistics (w ; kg/j +/- ) with an empirical limit of the maximum scaled distnace of ballistics (broken line). These bubbles are resulted from several charge explosion experiments (1.. +*...1 +* 1 J). This figure is modified from Taniguchi et al. (,***).. km -,* g (,) (.) /,**. 3 +,* *,. ++ km +.. +* +,,., +* +, J../ / km
,**. 3 + 201, +.*2*,*- : Baker, W. E., Cox, P. A., Westine, P. S., Kulesz, J. J. and Strehlow, R. A. (+32-) Explosion hazards and evaluation. Elsevier, Amsterdam, 2*1 p. Clancey, V. J. (+31,) Diagnostic features of explosion damage. 0th Int. Meeting of Forensic Sciences, Edinburgh. Goto, A., Taniguchi, H., Yoshida, M., Ohba, T. and Oshima, H. (,**+) E#ects of explosion energy and depth to the formation of blast wave and crater : field explosion experiment for the understanding of volcanic explosion. Geophys. Res. Lett.,,2,.,21.,3*. (+323) -.3-2/. Kinney, G. F. and Graham, K. J. (+32/) Explosive shocks in air. Springer-Verlag, New York,,03 p. (+31-).2 + - +- + +,+ p. (+33+).2. p. (,**.) +0 3 3 (,**.),**. 3,* (+33*).1 30 +*,. (,**/),**. 3 + 3,.-,/, (+3-*). +3- +30. Saito, T., Eguchi, T., Takayama, K. and Taniguchi, H. (,**+) Hazard predictions for volcanic explosions. J. Volcanol. Geotherm. Res., +*0, -3 /+. Sakuma, S. (+3/+) Damage on window-panes by the airwaves of explosion of Volcano Asama on Sept.,-, +3/*. Bull. Earthq. Res. Inst.,,., 0*/ 0+/. *. (,**.),**. 3 + S-.. Taniguchi, H. (+33-) Recent situation and plan for the explosion energy estimation of phreatomagmatic explosion. In Proceedings of the International Seminar of Physics of Vapor Explosions, edited by M. Akiyama,,0-,03. +2 (,***) 33 +333-3 p. (+30+),,.,./. (+32,) /1.,0 -*, +- +..