京 都 大 学 防 災 研 究 所 年 報 第 50 号 B 平 成 19 年 4 月
Annuals of Disas. Prev. Res. Inst., Kyoto Univ., No. 50 B, 2007

Shaking Table Tests on Cluttered Levels of Typical Medicine Shelves and Contents
Subjected to Earthquakes

Keng-Chang KUO, Yoshiyuki SUZUKI and Satoko KATSURAGI** Pharmacist of Kobe City
Synopsis
Cluttered situations due to overturned and fallen objects is a frequently observed phenomenon
after earthquakes. This study investigates quantitatively cluttered situations due to typical medicine
shelves and contents in hospitals by shaking table tests. Three types of typical medicine shelves are
adopted: stock shelf, tablet and powder medicine shelves. Input excitations include sinusoidal
waves and real earthquake motions. From the results of sinusoidal wave tests, quantitative
information on cluttered situations is expressed in maximum input accelerations and velocities.
Then, from the results of earthquake motion tests, the results of sinusoidal excitation tests arecompared and revised for evaluating the cluttered situations under earthquakes.
Keywords: clutter, overturning, hospital, medicine shelf, shaking table


1.

2.

Introduction

Cluttered situations due to overturned and fallen
objects is a frequently observed phenomenon after
earthquakes. Objects placed in a shelf drop out on thefloor and cause a cluttered situation before the shelfoverturns. Lots of researches on overturning of furniture
have been conducted. The criteria proposed by Ishiyama(1982) are extensively adopted to evaluate whether apiece of freestanding furniture overturns underearthquakes. However, compared with the studies on
overturning, so far no researches were conducted on
cluttered situations. Because the types of objects, shelves
and the methods of their placement are quite diverse, it isdifficult to obtain general criteria like those foroverturning. While, on the other hand, if the evaluation
objects are determined, an experimental approach willobtain direct and reliable results. Hence, this study
focuses on typical medicine shelves and contents in
hospitals, and investigates quantitatively the clutteredsituations by shaking table tests.

Shaking Table Test

2.1 Test specimens
The test specimens included three conventional typesof medicine shelves: stock shelf, tablet and powder
medicine shelves, as shown in Fig 1. Table 1 indicatesthe dimensions of the specimens. The breadth W andheight H of the shelf are the test parameters. Totally, five,
three and one specimens are adopted for the three types,
respectively. In the tests, to simulate the real situation to
the best extent, under a pharmacist’s directions, real
packages and bottles were infilled with sand bags to haveproper weights, and were placed in the shelves following
the same method in the hospitals.
2.2 Test setup, loading program and measurements
A series of tests were conducted in the Disaster
Prevention Research Institute (DPRI), Kyoto University.
The shaking table, with a plan dimension of 5 meter inlongitudinal direction by 3 meter in transverse direction,is capable of simulating three-directional excitations. A
reinforced concrete (RC) wall was constructed on the－ 107 －

shaking table along the table’s transverse direction forreproducing the conventional placement condition of the
shelf: against a wall (Fig. 2). The floor slab was sprayedwith linoleum that is a floor finishing material commonlyused in pharmacies and laboratories due to thecharacteristics of pollution-proof and easy-to-clean. To
observe and record test results conveniently, the floorslab is marked with grid lines at an interval of 20 cm.
The input excitations included two types: sinusoidal
waves and earthquake motions. As for the sinusoidal
wave, this study adopted the same settings as in the
researches on overturning of office furniture conductedby Kaneko et al. (2004) and Tamura et al. (2005). The
frequency and acceleration magnitude were set for each
excitation. The frequencies included 0.5, 0.75, 1.0, 1.5,
2.0 and 3.0 Hz, which are the likely range of equivalentfrequencies of earthquakes, calculated by Eq. 1 (Kaneko
et al. 1997).

Fe
where

Amax 2 ʌ Vmax

Amax

and

(1)

Vmax

are

the

maximum

At a given frequency, the acceleration magnitude wasincreased with each subsequent test till the specimen
overturned. The increments are 50~100 and 200 gal,
respectively, for frequency less and greater than 2.0 Hz.
Due to the capacity limit of the shaking table, the input
maximum acceleration is 250 and 1000 gal for frequencyof 0.5 and 0.75~3 Hz, respectively. The excitation timeof each sinusoidal wave was 25 seconds, includingtransient stages in the first and last five seconds. Fig. 3
shows the input sinusoidal wave of 1 Hz and acceleration
magnitude 100 gal. As for the earthquake motions, theadopted records included the 1968 Hachinohe NS, 1940
El Centro NS and 1995 JMA Kobe NS.
The specimens were placed against the RC wall anduni-axially excited along the shaking table’s longitudinal
direction. After each excitation, the motions of the shelfand cluttered situations were recorded. The cluttered area
was recorded based on the grid lines. At the top of the
shelf, three accelerometers were attached to measurevertical and two horizontal accelerations. An
accelerometer was also attached to the floor slab along
the excitation direction to measure the input acceleration.

acceleration and velocity of the input excitation.

(a) Stock shelf(b) Tablet medicine shelf (c) Powder medicine shelf
Fig. 1 Three types of medicine shelves

Table 1 Summary of test specimens
Type

1

180

30

90

2

180

30

150

180
150
210

30
30
30

180
90
90

180

25

90

180
180

25
25

150
180

180

15+60

180

3
4
5
6
7
8
9

Stock shelf

Tabletmedicine shelf
Powdermedicine shelf

150

Dimensions (cm)
H
B
W

W
B

H

Acceleration (cm/s/s)

NO.

－ 108 －

Sinusoidal excitation (1 Hz, PA=100 gal)

100
50
0
-50
-100
-150 0

Excitation
direction

Fig. 2 Test setup

5

10
15
Time (s)20

Fig. 3 Input of sinusoidal wave

25

3. Test Results
3.1 Input of sinusoidal waves(1) Observed characteristics of shelf motions andcluttered situations(a) Stock shelf
A predominant characteristic was that objects placedin the shelf began to drop from the lowers rows, while
those in the upper rows hardly dropped out (Fig 4). The
shelf was originally placed against the RC wall (Fig.5(a)), and medicine packages were placed along the frontedge of the layer panel for taking out and placing
conveniently. When the rocking motion was initiated, theshelf rotated backward to its original position andcollided with the wall. Due to the collision force theobjects slid backward. The collision force was greater atthe upper part of the shelf. Hence, the objects placed in
the upper rows slid backward much and even hit the backpanel, while those in the lower rows slid slightly (Fig. 5(c)).
On the other hand, Fig. 6 demonstrates theaccelerations at the slab and at the top of the shelf in the
excitation direction. In the figure, the peaks in thepositive direction were due to the collision with the wall.
While in the negative direction, the maximum absolutevalues were approximate for the accelerations at the topof the shelf and the slab. Response amplification was notobserved at the top of the shelf, so that the forward
sliding displacements of the objects placed at different
heights were approximate. As a result, the objects
dropped from the lower rows (Fig. 5 (d)), while those in
the upper rows rarely dropped out due to the large
backward sliding displacement.
(b) Tablet medicine shelf
The tablet medicine shelf showed the samecharacteristics as observed in the stock shelf. Bottles andcans began to drop from the lower rows (Fig. 7). By
contrast, the L-type drawers in the top shelf did not slide
out under all test excitations. The 1 mm-high stopper atthe edge of the layer panel demonstrated excellent
falling-proof effect.
(c) Powder medicine shelf
Different from the stock and tablet medicine shelves,the bottles placed in the top part of the powder medicine

shelf began to drop from the upper rows (Fig. 8).
Amplification of acceleration was observed at the top of
the shelf (Fig. 9). The reason is that the strength of themetal connection between the top shelf and bottom table
was not high enough, and the top shelf vibrated from theconnection base and showed response amplification. As
a result, the bottles placed in the upper rows were
subjected to greater excitations compared with those in
the lower rows.
(2) Overturning and cluttered levels
The test results are shown in Figs. 10~12. In thesefigures, the abscissa and ordinate are, respectively, theinput acceleration and velocity, calculated as Eq. 1. The
results of resting, rocking without clutter, rocking withclutter and overturning are noted as ٤, ٌ, ً and ‫ع‬,respectively. The number beside the symbol of ً
indicates the number of dropped items or the cluttereddistance in cm. Generally, the observed cluttered area
distributed approximately in the shape of rectangular or
trapezoidal. Hence, in recording the test results, thecluttered distance is recorded at the grid line where atleast 70% around the central part are scattered with fallen
objects. On the other hand, when the cluttered area wasapparently loose, the number of fallen objects is adopted
instead of the distance. While for the powder medicine
shelf, the falling ratio is recorded. Because the cylinderbottles roll around after dropping on the slab, it is withless meaning to describe the cluttered distance. In
consequent, for the powder medicine shelf, the number
beside the symbol of ً represents the falling ratio, andthe symbol of ‫ ع‬denotes falling of almost all contents.
For each type of the shelf, the results and discussions
on overturning and cluttered levels are summarized asfollows. In the figures the bold dashed lines represent thecritical acceleration and velocity dividing different
cluttered levels of the test results. In addition, the thinsolid lines shown in the figures are the lower limits ofoverturning acceleration and velocity (Eq. 2) proposedby Yazaki and Ishiyama (1996) for the placement
method of “against a wall”.

A0

B
g
H

V0

B
20
H

(2)

where A0 and V0 are the overturning acceleration (in－ 109 －

Fig. 4 Objects dropped from thelower rows in the stock shelf(a)Fig. 7 Objects dropped fromthe lower rows in the tablet
medicine shelf(b)Fig. 8 Objects dropped fromthe upper rows in the powder
medicine shelf

(c)

(d)

Input

Acceleration (cm/s/s)

Response

1000

0Acceleration (cm/s/s)

-1000

0

4

Time (s)(a) 1 Hz

1000

0

-1000

8

Response

1000

10Time (s)

12

Input

0

12 -1000 0

8

Acceleration (cm/s/s)

Acceleration (cm/s/s)

Fig. 5 Motions of the stock shelf and falling of medicine packages

4Time (s)812(b) 1.5 Hz

1000

0

-1000

8

10
Time (s)12(c) 2 Hz

Response

1000

Input

0

-1000

8

10
Time (s)12

Acceleration (cm/s/s)

Acceleration (cm/s/s)(d) 3 Hz
Fig. 6 Response at the top of the stock shelf (Specimen 1) under sinusoidal waves of 400 gal peak acceleration
Response

1000

Input

0

-1000

8

10
Time (s)(a) 2 Hz, 300 gal(b) 3 Hz, 300 gal
Fig. 9 Amplification of acceleration at the top of the powder medicine shelf(Specimen 9) subjected to sinusoidal waves－ 110 －

12

cm/s2) and velocity (in cm/s), respectively. B and H are
the breadth along the excitation direction and the heightof the shelf in cm, and g is the gravitational accelerationin cm/s2.
(a) Stock shelf(i) The rocking motion was initiated when the input
acceleration is greater thanBg (=163 gal), and theHoverturning velocity occurred at a nearly constant value.
The test results showed the same trend as those of
Yazaki-Ishiyama’s criteria (Eq. 2).
(ii) The cluttered situation occurred after theacceleration reached 400 gal, which is about thevalue Pg . The notation of P is the friction coefficient,
about 0.4, between the medicine packages and the steel
panel.
(iii) The initiation of cluttered situation wasdetermined by the acceleration, while the cluttereddistance was influenced simultaneously by theacceleration and velocity.
(iv) From the results of Figs. 10 (a), (b) and (c), forthe shelves with the same B/H ratio, the cluttereddistance was not influenced by the breadth of the shelfperpendicular to overturning direction, noted as W.
(v) From the results of Figs. 10 (a), (d) and (e), thedifference of the shelf heights of 150, 180 and 210 cm
did not influence the cluttered distance.
(vi) Under the input frequency of 0.5 and 0.75 Hz, nocluttered situation occurred before the shelf overturned.
By contrast, under the input frequency of 1.0~3.0 Hz, thecluttered situation occurred before the shelf overturned.
(b) Tablet medicine shelf
It is the same as observed in the test results of stock
shelves that the cluttered distance was not influenced by
the breadth of the shelf perpendicular to overturning
direction for the shelves with the same B/H ratio. Hence,
only one specimen’s results are shown in Fig. 11.
(i) The rocking motion was initiated when the input
acceleration is greater thanBg (=136 gal), and theHoverturning velocity occurred at a nearly constant value.
The test results showed the same trend as observed in thestock shelf.
(ii) The cluttered situation occurred at theacceleration of 250 gal, less thanPg(=400 gal).

Different from the stock shelf, medicine bottles wereplaced in the bottom row for the tablet medicine shelf.
Compared with the packages, the bottles were prone tooverturn before sliding. Thus the bottles overturned androlled out of the shelf at a smaller acceleration.
(iii) The number of fallen bottles showed a great
deviation. It is due to the collision between the bottles
and whether the overturned bottles rolled out of the
shelf. Lots of bottles overturned, while many of them
may not roll out of the shelf and resulted in fewer fallen
bottles on the slab. On the whole, at the acceleration of
300 gal, falling of about half bottles and cans wasobserved.
On the other hand, after the acceleration reachedPg (=400 gal), the cluttered situation increased rapidly,
as the packages also began to slide and dropped out.
(iv) Under the input frequency of 0.5 and 0.75 Hz, nocluttered situation occurred before the shelf overturned.
By contrast, under the input frequency of 1.0~3.0 Hz, thecluttered situation occurred before the shelf overturned.
This is the same as observed in the stock shelf..
(c) Powder medicine shelf(i) The friction coefficient P between the bottles
and the glass panel is about 0.3~0.35. While the initiationof fallen objects occurred at 200~250 gal, less than Pg(=300~350 gal). It is due to the response amplification of
the top shelf, as shown in Fig. 9.
(ii) The initiation of fallen objects was determined by
the acceleration, while the falling ratio was highly
correlated to the multiplication of acceleration andvelocity. The bold dashed lines representing constantvalue of acceleration multiplying velocity divided the test
results well, except the results of 1.5 Hz excitation at 200
and 300 gal. In the figure, the multiplications ofaccelerations and velocities for falling ratio of 6, 13, 30
and 40% are determined as 7.2 u 103, 1.28 u 104,
1.5 u 104and 2 u 104 cm2/s3, respectively.
3.2 Input of earthquake motions
The aim of tests using input of earthquake motions is
to investigate how to apply the results of sinusoidal wave
tests for evaluating the cluttered situation under realearthquake motions. The tests using input of earthquake
motions were conducted on one stock shelf (Specimen 2),
tablet medicine shelf (Specimen 7) and powder medicine
shelf (Specimen 9), respectively. The earthquake records－ 111 －

100
0.5 Hz 0.75 Hz 1 Hz

1.5 HzResting
Rocking w/o clutter
Rocking w/ clutter
Overturning

2 Hz

Velocity (cm/s)

80
70
70

60
1*
50

40

1*

3 Hz

90
90

70
70
50

20
1*

0

0

200

100
0.5 Hz 0.75 Hz 1 Hz

400
600
800
Acceleration (cm/s/s)
100

1.5 Hz

70

90
90

50

40

70

10*
6* 14*

20

70

50

0

200

70

60

22*

70
50

40

5*
6*

20

0
400
600
800 1000 1200 0
Acceleration (cm/s/s)(b) Specimen 2 (H180-W150-B30)
100

0.5 Hz0.75 Hz

1 Hz

1.5 Hz

3 Hz

90
90

70
70

200

400
600
800 1000
Acceleration (cm/s/s)(c) Specimen 3 (H180-W180-B30)

0.5 Hz 0.75 Hz 1 Hz

2 Hz

1.5 Hz

1200

2 Hz

50

60

3*

70

40

50
50
1*

20

30

90

3 Hz
90

70

Velocity (cm/s)

80

80
Velocity (cm/s)

2 Hz

12*

100

60

4*

40

50
50
6*

20

2*

0

Rocking w/ clutter
Overturning

1.5 Hz60
23*
5* 26* 20*
16* 14*
35
2*6*
17*

55

No falling

Falling

Falling of almost all contents

100
0.5 Hz

2 Hz

3 Hz

20

70

30

0
0
200
400
600
800 1000 1200
400
600
800 1000 1200
Acceleration (cm/s/s)
Acceleration (cm/s/s)(e) Specimen 5 (H210-W90-B30)(d) Specimen 4 (H150-W90-B30)
Fig. 10 Test results of the stock shelf subjected to sinusoidal waves (* denotes the number of fallen items)

0.5 Hz 0.75 Hz 1 Hz

40

90

200

Resting
Rocking w/o clutter

80

4*

3 Hz

6*

4*

100
Velocity (cm/s)

Velocity (cm/s)

30

3 Hz

0.75 Hz

1 Hz

80
Velocity (cm/s)

Velocity (cm/s)

70

60

0

1.5 Hz

80
50

0

1200

0.5 Hz 0.75 Hz 1 Hz

2 Hz

80

0

1000

(a) Specimen 1(H180-W90-B30)

40%

60
40
20

40%
35%
35%
13% 6%
3%0

1.5 Hz
2 Hz
55%
30%
13%
8%

3 Hz

40%
18%

40%

0 100 200 300 400 500 600 700 800
400
600
800 1000 1200
Acceleration (cm/s/s)
Acceleration (cm/s/s)
Fig. 11 Test results of the tablet medicine shelf subjected Fig. 12 Test results of the powder medicine shelf subjected
to sinusoidal waves (Specimen 8, H180-W180-B25; * to sinusoidal waves (Specimen 9, H180-W180-B15-60)
denotes the number of fallen items)
0200－ 112 －

Table 3 Accelerations for overturning and cluttered levels of
the stock shelf under sinusoidal waves and earthquakes(Equivalent frequency= 1.5 Hz)

Table 2 Summary of input earthquake motions

1968 Hachinohe NS

Equivalentfrequency
(Hz)
1.05

224, 500, 800

1940 El Centro NS

1.50

342, 500, 800

1995 JMA Kobe NS

1.44300, 500, 818

Name

Input max.
accel. (gal)

Input

Initiationof clutter

Dist. of
50 cm

Dist. of
70 cm

Overturning

400

500

600

754

500

875

1050

1320

Sinusoidal
excitation
Earthquake
motionTable 4 Accelerations for overturning and cluttered
Table 5 Accelerations for overturning and cluttered levels of thelevels of the tablet medicine shelf under sinusoidal
powder medicine shelf under sinusoidal waves and earthquakes
waves and earthquakes (Equivalent frequency= 1.5 Hz)(Equivalent frequency= 1.5 Hz; F.R. denotes falling ratio)
Input
Sinusoidal
excitation
Earthquake
motionInitiationof clutter

Falling ofhalf bottles

Overturning

250

300

450

438

525

788

Input
Sinusoidal
excitation
Earthquake
motionInitiationof clutter

F.R.=
6%

F.R.=
13%

F.R.=
30%

F.R.=
40%

200

260

347

376

434

350

455

607

658

760

Analysis results of earthquake motions
Analysis results of sinusoidal excitations
Median of overturning function for freestanding object
Twice the previous medianRocking without clutter
Rocking with clutter (Several pieces)Rocking with clutter (An area)

Velocity (cm/s)

Input acceleration (cm/s2)

160
140
120
100
80
60
40
20
0

Equivalent frequency (Hz)Fig. 13 Comparison of overturning accelerations undersinusoidal waves and earthquakes (Tamura et al. 2005)
Rocking without clutter
Rocking with clutter
Overturning

100

1 Hz

0.5 Hz1.5 Hz

0

200

400
600
800
Acceleration (cm/s/s)

3 Hz
1*

40

Falling of halfbottles and cans
Initiation of clutter

20
0

200

35cm

1000

1200

No falling
Falling
Falling ratio >40%

1 Hz

1.5 Hz

80

60

3 Hz
50cm

Initiation of clutter

0.5 Hz

Velocity (cm/s)

Velocity (cm/s)

9*

2 Hz

30
4*

3*

100

4*

1.5 Hz30

Fig. 14 Test results of the stock shelf subjected toearthquake motions (Specimen 2)

2 Hz

80

0

1 Hz

0.5 Hz

40%
8%

60

3 Hz

10%
5%

40

2 Hz

40%
13%

30%

6%

20
Initiation of falling400
600
800 1000 1200
Acceleration (cm/s/s)
Fig. 15 Test results of the tablet medicine shelfsubjected to earthquake motions (Specimen 7)

0

400
600
800 1000 1200
Acceleration (cm/s/s)
Fig. 16 Test results of the powder medicine shelfsubjected to earthquake motions (Specimen 9)－ 113 －

0200

Table 6 Cluttered levels for the stock shelf
Input
Accel.
(cm/s2)Vel.
(cm/s)

Initiationof clutter

Dist. of
50 cm

Dist. of
70 cm

Dist. of
90 cm

Overturning

500

875

1050

1400

㧙

㧙

56

74

93

140

Table 7 Cluttered levels for the tablet medicine shelf
Input
Accel.
(cm/s2)Vel.
(cm/s)

Initiationof clutter

Fallingof half
bottlesDist. of
35 cm

Dist. of
55 cm

Overturning

438

525

875

1225

㧙

㧙

㧙

56

65

84

dividing different cluttered levels, it is also assumed thatthe ratio is 1.75. While for the stock shelf theacceleration of initiation of clutter is revised to 500 gal
according to the results of earthquake motion tests. Figs.
14~16 demonstrate the results of earthquake motion tests.
In the figures, the bold line and dashed lines represent,
respectively, the predicted overturning limit and thecritical values dividing different cluttered levels underearthquakes, as indicated in Tables 3~5. It is found thatwell agreement between the predicted and test results for
all the three types of shelves.
4.
Criteria for Cluttered Levels of Typical
Medicine Shelves and Contents under Earthquakes

Due to the limited frequencies and accelerations ofTable 8 Cluttered levels for the powder medicine shelf
the input earthquakes, not all the results obtained in the(Initiation of falling: Accel>350 gal; F.R. denotes falling ratio)
sinusoidal wave tests were verified in the earthquake
F.R.=
F.R.=
F.R.=
F.R.=
motion tests. However, the predicted values of
Input
6%
13%
30%
40%
overturning and different cluttered levels underearthquakes showed well agreement with the limited test
Accel. u Vel.
22050
39200
45938
61250
results. Based on the test results, the criteria for(cm2/s3)
evaluating the cluttered situation under earthquakes are
summarized in Tables 6~8.
included the 1968 Hachinohe NS, 1940 El Centro NS
and 1995 JMA Kobe NS (Table 2). Their equivalent
5. Conclusions
frequencies, obtained by Eq. 1, were 1.05, 1.50 and 1.44
Hz, respectively. Besides the original PGA, the previous
In this chapter, shaking table tests are conducted onearthquake motions with maximum acceleration adjusted
investigation into cluttered situation due to typicalto 300, 500 and 800 gal were also input.
medicine shelves and contents. The specimens are theFor placement of “against a wall ”, Tamura et al.
real medicine shelves and contents. The input excitations(2005) conducted numerical analyses to compare theinclude sinusoidal waves and real earthquake motions.
overturning accelerations under sinusoidal waves andMajor conclusion from the test results are summarized as
earthquake motions, as shown in Fig. 13. Since this study
follows:
adopted the same settings for sinusoidal waves as those(1) From the results of sinusoidal tests, the initiationin the researches of Tamura et al. (2005), their analysesof cluttered situation occurs at 400, 250 and 200 gal,
results were referred to. As shown in Fig.13, theirrespectively, for the stock shelf, tablet and powder
analysis results indicated that averagely the overturning
medicine shelves.
accelerations under earthquake motions is much greater,(2) For the stock and tablet medicine shelves, underabout 1.5~2 times, than those under sinusoidal waves.
the sinusoidal excitations of 0.5 and 0.75 Hz, cluttered
Accordingly, in this study the overturning acceleration
situations do not occur before the shelf overturns; while
for earthquake motion tests is calculated as 1.75 times
for those with frequency of 1.0~3.0 Hz, clutteredthat obtained by sinusoidal wave tests. The last columns
situations occur before the shelf overturns. The
of Tables 3~5 indicate the overturning accelerations
maximum cluttered distances are 90 and 55 cm,
under sinusoidal waves and earthquake motions. The
respectively, for the two types of shelves.
tables show the results at frequency of 1.5 Hz, as one of(3) With the same B/H ratio of the shelf, the cluttered
the equivalent frequencies of the input earthquakes isdistance is not influenced by the breadth of the shelfaround this value. In the tables, for the accelerations
perpendicular to overturning direction.

－ 114 －

Kaneko, M., Nakamura, Y., Tamura, K. and Kambara, H.
(2004) “Difference of overturning behavior of officefurniture depending on its placement.” Journal of
Structural Engineering, AIJ, Vol. 50B, 679-685. (inJapanese)
Tamura, K., Nakamura, Y., Kaneko, M. and Kambara, H.
(2005) “Indoor safety evaluation method of buildings
for an earthquake.” Special Project for Earthquake
Disaster Mitigation in Urban Areas, 36-39. (inJapanese)
Yazaki, M., Hoshino, M. and Ishiyama, Y. (1996)“Criteria for overturning of rigid bodies with a wall.”Summaries of Technical Papers of Annual Meeting, AIJ,
1031-1034. (in Japanese)(4) For the powder medicine shelf, from the resultsof sinusoidal tests, the falling ratio is highly correlated
to the multiplication of acceleration and velocity.
(5) Under earthquake motions, the predicted values foroverturning and different cluttered levels, obtained bymultiplying a ratio of 1.75 with those of sinusoidal
excitation test, correspond well to the test results.
References
Ishiyama, Y. (1982) “Criteria for overturning of bodies
by earthquake excitations.” Journal of Structural andConstruction Engineering, AIJ, No. 317, 1-14.
Kaneko, M. and Hayashi, Y. (1997) “Overturning
criteria and horizontal displacement of rigid bodies toearthquake excitations.” Journal of StructuralEngineering, AIJ, Vol. 43B, 451-458. (in Japanese)ᝄേบታ㛎ߦࠃࠆౖဳ⊛ߥ⮎೷᫜࡮ౝኈ‛ߩ࿾㔡ᤨᢔੂ⁁ᴫߩ⹏ଔㇳ⠹᧟࡮㋈ᧁ␽ਯ࡮᩵ᧁ⡡ሶ *␹ᚭᏒ⮎೷Ꮷⷐ ᣦᧄ⎇ⓥߢߪ‫ޔ‬ἴኂ᜚ὐߢ޽ࠆ∛㒮ߩ⮎೷᫜࡮ౝኈ‛ࠍኻ⽎ߣߒߡ‫ޔ‬࿾㔡ᤨߩቶౝᢔੂ⁁ᴫߦߟ޿ߡ‫ޔ‬ᝄേบታ㛎ࠍታᣉߒߡቯ㊂⊛ߦ⹏ଔߔࠆ‫⹜ޕ‬㛎૕ߪࠬ࠻࠶ࠢ᫜‫ޔ‬㍤೷᫜‫ޔ‬ᢔ೷᫜ߩ㧟⒳㘃ߩౖဳ⊛ߥ᫜ࠍ฽߻‫ޔߕ߹ޕ‬ᱜᒏᵄࠍ౉
ജߒ‫ޔ‬᫜ߩ⒳㘃ߦࠃࠆᢔੂߩ․ᓽߩ㆑޿ߥߤቯᕈ⊛ߥᛠីࠍⴕ߁ߣߣ߽ߦ‫౉ޔ‬ജߩടㅦᐲ߿ᝄേᢙߦࠃࠆᢔੂ〒㔌ߩᄌൻߥߤࠍቯ㊂⊛ߦ⹏ଔߒߚ‫ޕ‬ᰴߦ‫ޔ‬࿾㔡ᵄࠍ౉ജߒ‫ޔ‬ᱜᒏᵄߩ౉ജߢᓧࠄࠇߚ⚿ᨐߣߩ㑐ଥࠍಽᨆߒߚ਄ߢ‫ޔ‬࿾㔡ᤨߦ᫜ߩౝኈ‛߇ᢔੂߔࠆ〒㔌෸߮㕙Ⓧߩ੍᷹ᑼࠍዉߊ‫ޕ‬ࠠ࡯ࡢ࡯࠼: ᢔੂォୟ∛㒮⮎೷᫜ᝄേบ

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