捷運技術半年刊 第 35 期 95 年 8 月

59

Crashworthiness Analysis of CK371

Tomonori Umebayashi1 Toshinori Kimura2 Hiroyuki Morimoto3 陳立島 4

Abstract

Crashworthiness requirements are appearing more frequently in rail vehicle technical specifications. These requirements represent an effort to reduce the number of injuries and fatalities to rail passengers in collisions. There are relatively few published studies that provide methodologies for analyzing the crash behavior of rail vehicles.

This paper presents CK371 two train crash analysis and crush element test results. Mechanical fuse element behavior is shown to be predictable using Kawasaki’s analysis method, which employs LSTC/LS-DYNA.

Key Words：crashworthiness

CK371 標電聯車車體結構抗撞分析

川崎重工業株式會社

摘 要

車體結構抗撞性能需求經常規定於軌道車輛技術合約內。此需求的目的在盡可能降低車輛碰撞時乘客受傷或死亡的數目。有關於分析軌道車輛碰撞行為研究甚少有公開發表之文章。

本文提供 CK371 標電聯車的兩列車碰撞分析與車體碰撞元件測試結果。Kawasaki 使用LSTC/LS-DYNA 分析方法，顯示機械保險裝置的碰撞行為是可以預測的。

關鍵詞：抗撞

1. Assistant Manager, Kawasaki Heavy Industries, Ltdumebayashi_t@khi.co.jp

2. Senior Manager, Kawasaki Heavy Industries, Ltdkimura_to@khi.co.jp

3. CK371 Deputy Project Manager, Kawasaki Heavy Industries, Ltdmorimoto_h@khi.co.jp

4. CK371 Project Manager, Kawasaki Heavy Industries, Ltdlitao_chen@khitpe.com.tw

Tomonori Umebayashi Toshinori Kimura Hiroyuki Morimoto 陳立島 CRASHWORTHINESS ANALYSIS OF CK371

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1、Scope

In accordance with the CK371 particular technical specification（PTS）requirements, the car body structure crashworthiness analysis is summarized herein. The crashworthiness analysis is performed using LSTC/LS-DYNA [1] time-dependent, large-deflection computer program, to grasp the fuse deformation of six - car train set at the collision with another six - car train. PTS requirements are the followings.

a. An analysis shall be conducted of an impact between one 6-car train with W4 loading moving at 25 km/hr and one parked 6-car train with W1 and W4 loadings.

b. A structural mechanical “fuse” shall have a buckling strength less than 50 percent of the column buckling strength of the main structure.

c. Further collapse shall cause full engagement of the adjoining car ends with deformation of its fuse limited to the cab, and equipment locker area in the case of the non-cab car ends so that passenger space is unaffected.

2、Analysis

2.1 Mass-spring model

To analyze the behavior in the case of collision between two train sets, where one six–car train is parked and the other six– car train collides at a speed of 25 km/hr, a mass-spring model [2] of two train is used. Spring of fuse and coupler are obtained from section 2-2 as shown below.

Table 2-1 shows that two cases are analyzed by LS-DYNA equation in order to investigate the collision behavior.

CASE 1: Collision of a W4 (full loaded)

loaded six – car train with a W1

(empty car) six–car train that is

parked.

CASE 2: Collision of a W4 loaded six –car

train set with a W4 loaded six –car

train that is parked.

A01 A02 A03 A04 A05 A06 B01 B02 B03 B04 B05 B06DM1 T M2 M2 T DM1 DM1 T M2 M2 T DM1

40.0ton 34.9ton 39.1ton 39.1ton 34.9ton 40.0ton 62.2ton 57.1ton 61.3ton 61.3ton 57.1ton 62.2ton

A01 A02 A03 A04 A05 A06 B01 B02 B03 B04 B05 B06DM1 T M2 M2 T DM1 DM1 T M2 M2 T DM1

62.2ton 57.1ton 61.3ton 61.3ton 57.1ton 62.2ton 62.2ton 57.1ton 61.3ton 61.3ton 57.1ton 62.2ton

Parked train(Wtotal=228ton、V0=0、μ＝0.12）

Compressive characteristic：2c Compressive characteristic：2c

Moving train(Wtotal=361.2ton、V0=25km/h、μ＝0）

Fig. 2-3-1 Model and boundary condition of case 1

Compressive characteristic ：1e

Parked train(Wtotal=361.2ton、V0=0、μ＝0.12）

Compressive characteristic：2c Compressive characteristic：2c

Moving train(Wtotal=361.2ton、V0=25km/h、μ＝0）

Fig. 2-3-2 Model and boundary condition of case 2

Compressive characteristic ：1e

Fig.2-1-1 Model and boundary condition of case 1

Fig.2-1-2 Model and boundary condition of case 2

Table 2-1 Calculation cases

Train Condition

Moving car Parked car CASE Weight Velocity

(km/h) Weight Velocity

(km/h) 1 W4 25 W1 0

2 W4 25 W4 0

捷運技術半年刊 第 35 期 95 年 8 月

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2.2 2.2 Load-Deformation Curve

The springs used in this analysis have non-linear characteristics, i.e., a non-linear load deformation curve (P-δcurve). Characteristics of coupler-fuse-carbody system is obtained from the below items 1), 2) and 3).

1) Characteristic of coupler

The load-deformation curve of the coupler that is submitted from supplier is shown in Fig.2-2-1. When the coupler deformation is less than 50 mm, the spring of the coupler is elastic (zone I: double-acting draft gear). When the deformation exceeds 50 mm, the emergency release bolts break, and the energy absorber absorbs the collision energy until the deformation becomes 230 mm (zone II: one shot E.A. II absorber), except for DM1 car where 75 mm is the total deformation. At this point, the stroke of the E.A. II absorber has been fully utilized, and further deformation will result in the coupler anchorage bolts shearing off, after which the coupler force will be zero.

2) Characteristics of fuse

Elastic Plastic characteristic of fuse elements which are located at the cab end and non-cab end are shown in Fig. 2-2-2, are analyzed by LSTC/LS-DYNA and confirmed by the crush test.

2-1) Analysis result

The analysis model of cab end fuse element is shown in Fig. 2-2-3. The analysis results of cab end, which is “1e” in Fig. 2-1-1 and Fig. 2-1-2, are shown in Fig. 2-2-4. The analysis results are deformation, reaction force and absorbed energy. Maximum buckling strength of cab end fuse is 3,122kN (= one (1) mechanical fuse buckling strength x two (2) fuses= 1,561kN x 2).

Fig. 2-2-3 Analysis model of cab end fuse element

F 圖 2 4 G l fi ti Fig. 2-2-1 General configuration and characteristics of coupler Fig.2-2-2 Taipei EMU end underframe

Tomonori Umebayashi Toshinori Kimura Hiroyuki Morimoto 陳立島 CRASHWORTHINESS ANALYSIS OF CK371

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Deformation （model １e）

δ=0mm δ=50mm δ=100mm δ=150mm

δ=200mm δ=250mm δ=300mm δ=350mm

0

400

800

1200

1600

2000

2400

0 50 100 150 200 250 300 350 400

Displacement [mm]

For

ce [

KN

]

model １e

0

0.1

0.2

0.3

0.4

0.5

0 50 100 150 200 250 300 350 400

Displacement [mm]

Ene

rgy

[ＭＪ

]

model １e

Fig.2-2-4 Analysis result of end fuse element

2-2) Test result

The cab and non-cab end fuse elements were tested respectively to confirm their crush behavior. Original and crushed shape of cab end are shown in Fig. 2-2-5.

Fig.2-2-6 shows that the crush deformation versus reaction force during crush test, together with the result of analysis. Analysis and test results agree closely until 140 mm displacement.

Fig. 2-2-6 Results of analysis and test

0

200

400

600

800

1,000

1,200

1,400

1,600

1,800

2,000

0 50 100 150 200 250 300Displacement (mm)

Load

(kN

)

Test result

Allowable Strength

Analysis result

One Mechanical Fuse Buckling Strength(Cab End) Fc=1577.63 kN

One Fuse Allowable strength: 1692.25kN(=6,769kN/4)

Fuse length = 240mm

Fc=1680.6kN at 240mm mean displacement

Fig. 2-2-5 Cab end fuse element crush test

Original（unloaded） Crushed（loaded）

捷運技術半年刊 第 35 期 95 年 8 月

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3) Characteristics of carbody

The carbody column buckling strength of the car body which is obtained from static analysis results by using MSC/NASTRAN is 6,769kN.

4) Combined characteristics of coupler-fuse-carbody system

The combined characteristics of coupler-fuse-carbody system of cab end and non cab end which is obtained from the above mentioned 1) through 3) are shown in Fig. 2-2-7.

2.3 Analysis Program

The two train collision analysis with mass-spring model [2] shown in Fig. 2-1-1 and Fig. 2-1-2 using analysis program of LSTC/LS-DYNA is implemented.

3、Results

1) Case 1

Fig. 3-1-1 shows force vs. time between each car. Force acting on each fuse is less than their designed strength (50% of carbody column buckling strength = 0.5 x 6,769kN=3,385kN). Fig. 3-1-2 shows the deformation of the fuse excluding coupler deformation, i.e. the deformation mentioned in minus the deformation of coupler. For the cab end, it is found that the fuse deformation of no.1 end of the lead car (car number B01) is the largest (and equal to that of car number A06). The maximum value of fuse deformations is about 158 mm, which is less than the fuse length of 240 mm for these cars.

For the non cab end, it is found that the fuse deformation of no.2 end (car number B01 and B02) is the largest. The maximum value of fuse deformations is about 98 mm, which is less than the fuse length of 120 mm for these cars.

2) Case 2

Fig. 3-2-1 shows force vs. time. For each car, Force acting on fuse elements is less than above the mentioned design strength. Fig. 3-2-2 shows the deformation of the fuse excluding coupler deformation, i.e. the deformation mentioned in minus the deformation of coupler. For the cab end, it is found that the fuse deformation of no.1 end of the lead car (car number B01) is the largest (and equal to that of car number A06). The maximum value of fuse deformations is about 201 mm, which is less than the fuse length of 240 mm for these cars. Thus, each fuse meets specification requirement of PTS.

Compressive characteristic of cab end side

0

1600

3200

4800

6400

8000

9600

11200

12800

14400

0.000 100.000 200.000 300.000 400.000 500.000 600.000

Destructive displacement (mm)

Load

(KN

)

1e：No.1 End of DM (SMA490、plate thickness t8+t6)

Compressive characteristic of non cab end side

0

1600

3200

4800

6400

8000

9600

11200

12800

14400

0.000 100.000 200.000 300.000 400.000 500.000 600.000

Destructive displacement (mm)

Load

(KN

)

2c：Non Cab End (SMA490, Plate thickness t8+t6)

Fuse characteristic

Couplercharacterictic

Couplercharacteristic

No loading

Fuse characteristic

Carbody characteristic

Carbody characteristic

Fig. 2-2-7 Combined characteristics of coupler-fuse-carbody

Tomonori Umebayashi Toshinori Kimura Hiroyuki Morimoto 陳立島 CRASHWORTHINESS ANALYSIS OF CK371

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For the non cab end, it is found that the fuse deformation of no.2 end (car number A04 and A05) is the largest. The maximum value of fuse deformations is about 111 mm, which is less than the fuse length of 120 mm for these cars.

3) Relation between carbody column buckling strength and fuse buckling strength

Carbody column buckling strength is 6,769kN. On the other hand, as shown in Fig. 2-2-4, the maximum buckling strength of 3122 kN (= one (1) mechanical fuse buckling strength x two (2) fuses= 1,561kN x 2) at the cab end and 2,998kN (= one (1) mechanical fuse buckling strength x two (2) fuses= 1,499kN x 2) at the non cab end are less than 50% of column buckling strength of above the mentioned value. Thus, carbody column buckling strength and fuse buckling strength meet specification requirement of PTS.

4、Conclusion

With respect to rail vehicles, for which demands for the evaluation of crashworthiness have been increasing in recent years, we have in this report initially compared the results of a compression test on the fuse element that absorbs the crash energy with those of calculations, and confirmed that the numerical calculations proved sufficiently accurate to predict the result.

Two trains collision are analyzed and the results are in accordance with the PTS requirements.

Consequently, it has been shown that it is possible on the one hand to design a rail vehicle’s carbody structure taking crashworthiness into account, and on the other to design a carbody structure taking the crash safety into account by evaluating the behaviors during a crash by means of simulated calculations.

Reference

1. LS-DYNA KEYWORD USER’S MANUAL March 2001 Version 960 Livermore Software Technology Corporation.

2. Kawasaki Technical Review Oct.1991 No.111 Kawasaki Heavy Industries, Ltd. “Crashworthiness of Taipei Electric Multiple Unit Train” Tokio Ohnishi, Koji Wada, Mitsuji Yoshino, Atsushi Sano.

Deformation of Fuse vs. Time (Case 2) (,W4+W4)

-300

-200

-100

0

100

200

300

400

500

0.00 0.50 1.00 1.50 2.00 2.50

Time (sec)D

efo

rmat

ion o

f Fuse

（exc

ludi

ng

coupl

er

defo

rmat

ion：m

m)

A01-A02

A02-A03

A03-A04

A04-A05

A05-A06

A06-B01

B01-B02

B02-B03

B03-B04

B04-B05

B05-B06

Fig.3-2-2 Deformation of fuse vs. Time (case 2)

Force vs. Time between each cars (Case 1) (W1+W4)

-3500

-3000

-2500

-2000

-1500

-1000

-500

0

0.00 0.50 1.00 1.50 2.00 2.50

Time (sec)

For

ce (

KN

)

A01-A02

A02-A03

A03-A04

A04-A05

A05-A06

A06-B01

B01-B02

B02-B03

B03-B04

B04-B05

B05-B06

Fig.3-1-1 Force vs. Time(case 1) Deformation of Fuse vs. Time (Case 1) (,W1+W4)

-200

-100

0

100

200

300

400

500

0.00 0.50 1.00 1.50 2.00 2.50

Time (sec)

Defo

rmat

ion o

f Fuse

（exc

ludi

ng

coupl

er

defo

rmat

ion：m

m)

A01-A02

A02-A03

A03-A04

A04-A05

A05-A06

A06-B01

B01-B02

B02-B03

B03-B04

B04-B05

B05-B06

Fig. 3-1-2 Deformation of fuse vs. Time (case 1)

Force vs. Time between each cars (Case 2) (W4+W4)

-3500

-3000

-2500

-2000

-1500

-1000

-500

0

0.00 0.50 1.00 1.50 2.00 2.50

Time (sec)

For

ce (

KN

)

A01-A02

A02-A03

A03-A04

A04-A05

A05-A06

A06-B01

B01-B02

B02-B03

B03-B04

B04-B05

B05-B06

Fig. 3-2-1 Force vs. Time (Case 2)