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10.1109@rrcon.1990.171665 .pdf



Original filename: 10.1109@rrcon.1990.171665.pdf
Title: New Haven line catenary replacement - Railroad Conference, 1990., Technical Papers Presented at the 1990 ASME/IEEE Joint
Author: IEEE

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NEW HAVEN LINE CATENARY REPLACEMENT
Michael W. Savchak, P.E.
Deputy D i r e c t o r - T r a n s p o r t a t i o n E n g i n e e r i n g
M e t r o - N o r t h Commuter Rai 1r o a d
347 Madison Avenue
New York, New York 10013
Introduction

o r d e r t o m i n i m i z e t h e s e v o l t a g e drops.

Anyone who has observed t h e 1907 v i n t a g e c a t e n a r y
system w h i l e r i d i n g M e t r o - N o r t h Commuter R a i l r o a d ' s
New Haven l i n e must have been s t r u c k by t h e i n t r i c a t e
t r a c e r y o f t h e t r i a n g u l a r overhead w i r e s as t h e y
s t r e t c h o u t i n t o t h e distance. It i s e s p e c i a l l y
d r a m a t i c t o observe t h e w i r e s a t sunset f r o m t h e
r e a r o f a speeding t r a i n , when one can watch t h e
r h y t h m i c r i s e and f a l l o f t h e messenger s i l h o u e t t e d
a g a i n s t a reddening sky. U n f o r t u n a t e l y , a e s t h e t i c s
cannot overcome t h e e f f e c t s o f age, and t h e p u b l i c ' s
demand f o r e f f i c i e n t d a i l y o p e r a t i o n l e a v e s l i t t l e
room f o r a system which r e q u i r e s an i n o r d i n a t e
amount o f d a i l y maintenance and which i s no l o n g e r
r e l i a b l e . The g r a c e f u l o l d must be r e p l a c e d w i t h a
more p r a c t i c a l new.

I n c o n t r a s t t o t h i s , a h i g h v o l t a g e A.C. system
c o u l d p r o v i d e t h e necessary power w i t h a minimum
number o f s u b s t a t i o n s . An overhead system o f c u r r e n t
c o l l e c t i o n would e l i m i n a t e t h e need f o r an exposed
t h i r d r a i l , and b y u t i l i z i n g a s e r i e s commutator
motor, t h e same motor c o u l d o p e r a t e on b o t h D.C. and
A.C. systems. The o n l y problem w i t h t h i s system was
t h a t i t was u n t r i e d . D e s p i t e t h i s , t h e New Haven
chose t o proceed w i t h an 11,000 v o l t , 25 h e r t z ,
s i n g l e phase system.
The c u r r e n t c o l l e c t i o n system chosen was an overhead
c a t e n a r y system c o n s i s t i n g o f two g a l v a n i z e d s t e e l
messengers s u p p o r t i n g a copper t r o l l e y w i r e i n a
t r i a n g u l a r c o n f i g u r a t i o n . Such a c o n f i g u r a t i o n gave
good v e r t i c a l s u p p o r t w h i l e p r o v i d i n g l a t e r a l
stiffness.

The r i d i n g p u b l i c i s p r i m a r i l y concerned w i t h i t e m s
such as c l e a n l i n e s s o f t h e equipment; whether t h e
l i g h t s , h e a t o r a i r c o n d i t i o n i n g work; and, most o f
a l l , whether t h e t r a i n a r r i v e s on time. As t h e
power system i s d i r e c t l y r e l a t e d t o two o f t h e s e
concerns, M e t r o - N o r t h j u s t l y p l a c e d an emphasis on
i t s m o d e r n i z a t i o n . Thus, i n excess o f $277,000,000
was s e t a s i d e f o r t h e improvements t o t h e r a i l r o a d ' s
power systems. T h i s f u n d i n g p e r m i t t e d t h e r a i l r o a d
t o r e p l a c e a l l o f i t s o b s o l e t e r o t a r y c o v e r t e r subs t a t i o n s w i t h 38 new s o l i d s t a t e s u b s t a t i o n s , r e p l a c e
a p p r o x i m a t e l y 200 m i l e s o f worn 70 l b . c o n t a c t r a i l
w i t h new 150 l b . c o n t a c t r a i l , p r o v i d e remote c o n t r o l
o f a l l s u b s t a t i o n s , and make o t h e r s i g n i f i c a n t i m provements. The replacement o f t h e New Haven
c a t e n a r y system i s t h e l a s t m a j o r element of t h i s
program. T h i s paper w i l l d e s c r i b e t h e e n g i n e e r i n g
processes i n v o l v e d i n t h e p l a n n i n g and d e s i g n o f
t h i s replacement p r o j e c t .

C o n s t r u c t i o n o f t h e new system commenced i n 1905 and
on J u l y 24, 1907, t h e f i r s t revenue t r a i n was
operated. As w i t h a l l new systems, m o d i f i c a t i o n s t o
t h e o r i g i n a l system had t o be made. One such
m o d i f i c a t i o n , made around 1910, was t h e a d d i t i o n o f
a bronze c o n t a c t w i r e i n p l a c e o f t h e o r i g i n a l copper
c o n t a c t w i r e . The new w i r e was a t t a c h e d t o t h e o l d
w i r e which t h e n became an a u x i l i a r y w i r e . Between
1981 and 1986 t h e system was c o n v e r t e d t o 12,500
v o l t s , 60 h e r t z , b u t t h e r e were no r e v i s i o n s t o t h e
c a t e n a r y system w h i c h remained i n i t s p r e s e n t
configuration.
F u t u r e e x t e n s i o n s o f e l e c t r i f i c a t i o n on t h e New Haven
l i n e u t i l i z e d d i f f e r e n t catenary c o n f i g u r a t i o n s , b u t
t h e o r i g i n a l t r i a n g u l a r c o n f i g u r a t i o n was n o t
s i g n i f i c a n t l y changed. The t r i a n g u l a r c o n f i g u r a t i o n
i s r a t h e r unique amongst c a t e n a r y systems t o t h e
p o i n t t h a t t h e a u t h o r knows o f o n l y one o t h e r system
which was s i m i l a r . T h i s was a 6600 v o l t , 25 h e r t z
system adopted b y t h e London, B r i g h t o n and Southcoast
Railway i n s o u t h e a s t England. T h i s system a l s o had
a t r i a n g u l a r c a t e n a r y system and was o p e r a t e d between
1909 and 1929, when i t was c o n v e r t e d t o a 600 v o l t
O.C. system u s i n g a t h i r d r a i l . The system was
designed b y a German company, AEG. What i s
i n t e r e s t i n g i s t h a t , u l t i m a t e l y , t h e replacement f o r
t h e t r i a n g u l a r system would be based upon a B r i t i s h
design.

'Background
I n 1905, t h e New York, New Haven and H a r t f o r d
R a i l r o a d announced t h a t i t would e l e c t r i f y i t s main
l i n e between Woodlawn, New York and Stamford,
C o n n e c t i c u t . A 1903 l a w r e q u i r e d t h a t a l l t r a i n s
e n t e r i n g Grand C e n t r a l Terminal a f t e r J u l y 1, 1908
c o u l d no l o n g e r be h a u l e d by steam l o c o m o t i v e s . The
New York C e n t r a l R a i l r o a d , which owned t h e l i n e i n t o
Grand C e n t r a l , a l r e a d y had decided upon u t i l i z i n g a
700 v o l t D.C. u n d e r r u n n i n g t h i r d r a i l system f o r i t s
e l e c t r i f i c a t i o n . The New Haven had been o p e r a t i n g
s e v e r a l 600 v o l t D.C. e l e c t r i f i e d l i n e s u t i l i z i n g
e i t h e r a c e n t e r t h i r d r a i l o r an overhead w i r e w i t h
t r o l l e y p o l e c u r r e n t c o l l e c t i o n s i n c e 1895. Thus, i t
was expected t h a t t h e New Haven would choose a
s i m i l a r system f o r i t s e l e c t r i f i c a t i o n . However,
t h e r a i l r o a d determined t h a t t o r e a l i z e t h e f u l l
benefits o f the e l e c t r i f i c a t i o n , a greater extent o f
r a i l r o a d t h a n j u s t t h e t e r m i n a l area had t o be
e l e c t r i f i e d . A l l o f i t s mainline services, including
commuter, l o n g d i s t a n c e passenger and f r e i g h t , had
t o be e l e c t r i c a l l y powered. I t was t h e s e c r i t e r i a
which weighed a g a i n s t t h e c h o i c e o f a l o w v o l t a g e
D.C. system. The h i g h t r a c t i o n c u r r e n t s would
r e s u l t i n c o r r e s p o n d i n g l y h i g h v o l t a g e drops i n t h e
t h i r d r a i l . T h i s would n e c e s s i t a t e t h e c o n s t r u c t i o n
o f numerous s u b s t a t i o n s t o g e t h e r w i t h a power
d i s t r i b u t i o n system l i n k i n g each s u b s t a t i o n , i n

I n essence, a l m o s t a l l of t h e components o f t h e
c a t e n a r y system have been i n s e r v i c e f o r o v e r e i g h t y
y e a r s . D u r i n g t h i s p e r i o d , d e t e r i o r a t i o n has s e t i n
f r o m c o r r o s i o n , wear and f a t i g u e . System r e l i a b i l i t y
has d i m i n i s h e d and i t has become o b v i o u s t h a t t h e
system i n i t s p r e s e n t c o n f i g u r a t i o n has become
u n s u i t a b l e f o r f u t u r e use.
Study E f f o r t s
I n o r d e r t o determine t h e r a i l r o a d ' s c o u r s e o f a c t i o n
w i t h r e g a r d t o t h e c a t e n a r y system, i t was f i r s t
necessary t o p e r f o r m a p r e l i m i n a r y e n g i n e e r i n g study.
As f u n d i n g was a v a i l a b l e o n l y i n t h e S t a t e o f New
York, t h e s t u d y l i m i t e d i t s e l f t o t h a t p o r t i o n o f t h e
c a t e n a r y system t h a t i s w i t h i n t h e S t a t e o f New York.
T h i s study, conducted f o r M e t r o - N o r t h b y t h e f i r m o f
91

EMJ-McFarland Johnson i n 1984-85, had e i g h t m a j o r
t a s k s . They were as f o l l o w s :
1.

P e r f o r m an e x a m i n a t i o n o f t h e e x i s t i n g c a t e n a r y
system t o d e t e r m i n e i t s e x i s t i n g c o n d i t i o n .

2.

Study system maintenance t o d e t e r m i n e what
procedures and equipment can be improved.

3.

Develop n e a r t e r m s o l u t i o n s i n o r d e r t o a r r e s t
f u r t h e r system d e t e r i o r a t i o n .

4.

Develop l o n g r a n g e s o l u t i o n s , i n c l u d i n g f u l l or
p a r t i a l r e p l a c e m e n t o f t h e c a t e n a r y system.

5.

S t u d y system c a p a c i t y and v o l t a g e l e v e l s t o
d e t e r m i n e system c a p a c i t y .

6.

Study p a n t o g r a p h c o m p a t i b i l i t y w i t h e x i s t i n g and
proposed systems.

7.

Develop p r e m i l i n a r y c o s t e s t i m a t e s .

8.

Prepare a f i n a l r e p o r t d e t a i l i n g t h e r e s u l t s o f
t h e study.

e s t a b l i s h e d procedures. As a r e s u l t o f t h i s
recommendation, a new w i r e t r a i n was d e s i g n e d and a t
t h e t i m e o f w r i t i n g , b i d s a r e b e i n g sought f o r i t s
construction.

A p r e l i m i n a r y c o s t e s t i m a t e was p r e p a r e d w h i c h became
t h e b a s i s f o r a r e q u e s t f o r f u n d i n g under t h e n e x t
MTA c a p i t a l improvements program. The p r o j e c t was
approved as a component o f t h e MTA's second f i v e y e a r
c a p i t a l improvements program and a u t h o r i z a t i o n t o
commence d e s i g n was g i v e n .
Design E f f o r t s

-

I n i t i a l Stages

Once a u t h o r i z a t i o n t o proceed w i t h t h e p r o j e c t was
given, t h e r a i l r o a d r e t a i n e d t h e s e r v i c e s o f
M o r r i son-Knudsen Engineers (MKE) t o p e r f o r m t h e
necessary d e s i g n s e r v i c e s f o r t h e r e p l a c e m e n t c a t e n a r y
system and t h e r e p l a c e m e n t w i r e t r a i n . One o f t h e
i n i t i a l t a s k s was a r e v i e w o f t h e recommendations o f
t h e p r e l i m i n a r y engineering study. U t i l i z i n g c r i t e r i a
p r o v i d e d b y t h e r a i l r o a d , a recommendation was made
t o employ a f i x e d t e r m i n a t i o n , v a r i a b l e t e n s i o n
c a t e n a r y system. However, i n t h e i n t e r i m p e r i o d s i n c e
t h e p r e l i m i n a r y e n g i n e e r i n g s t u d y was completed, t h e r e
have been s e v e r a l r e v i s i o n s t o t h e b a s i c c r i t e r i a . A
s e r i e s o f p a n t o g r a p h dewirements i n d i c a t e d t h a t i t
would be d e s i r a b l e t o r e d u c e t h e o v e r a l l w i r e h e i g h t
f r o m a p p r o x i m a t e l y 22 f e e t above t o p o f r a i l t o 18
f e e t above t o p o f r a i l . The maximum o p e r a t i n g speed
was o r i g i n a l l y s p e c i f i e d as 90 m i l e s p e r hour. As a
r e s u l t o f a d e s i r e t o i n c r e a s e speeds, as w e l l as
accommodate p o s s i b l e f u t u r e h i g h speed s e r v i c e (under
t h e CONEG p l a n ) , t h e maximum o p e r a t i n g speed was
s p e c i f i e d as 95 mph, w i t h a c a p a b i l i t y t o be r a i s e d t o
110 mph.

A d e t a i l e d p h o t o g r a p h i c s u r v e y was made o f e v e r y
c a t e n a r y s u p p o r t s t r u c t u r e , as w e l l as s i g n i f i c a n t
elements o f t h e overhead w i r e s . These s u r v e y s
i n d i c a t e d , f o r example, t h a t 80% o f t h e s t r u c t u r e
f o u n d a t i o n s had v a r y i n g degrees o f damage r a n g i n g
from minor cracking t o major s p a l l i n g o f concrete.
An equal number o f column bases were d e t e r i o r a t e d
due t o c o r r o s i o n . A p p r o x i m a t e l y 405 o f t h e beamcolumn c o n n e c t i o n s were f o u n d t o be d e t e r i o r a t e d ,
and t h e same r a t i o a p p l i e d t o d e t e r i o r a t e d beam
members and s p l i c e s . A t o t a l o f 80 p r i o r i t y
r e p a i r s t o s t r u c t u r a l elements were i d e n t i f i e d as
a n e a r t e r m p r o j e c t . These r e p a i r s were t h e n u n d e r taken by r a i l r o a d s t r u c t u r a l forces. For t h e l o n g e r
term, a t o t a l o f 539 second o r d e r p r i o r i t y r e p a i r s
were i d e n t i f i e d . Some o f t h e s e r e p a i r s were undertaken by r a i l r o a d f o r c e s , w h i l e others a r e being
d e f e r r e d u n t i l system r e c o n s t r u c t i o n . W h i l e most o f
t h e w i r e was f o u n d t o be i n s a t i s f a c t o r y c o n d i t i o n ,
s e v e r a l d e f i c i e n c i e s i n temporary r e p a i r s were n o t e d
and recommendations were made t o improve t e n s i o n i n g
and p u l l o f f arrangements.
I n s t u d y i n g t h e replacement system, c a t e n a r y systems
w o r l d w i d e were examined t o d e t e r m i n e t h e i r
s u i t a b i l i t y . One m a j o r c o n s t r a i n t was t h e e x i s t i n g
s u p p o r t s t r u c t u r e s p a c i n g o f 300 f e e t . Most modern
systems have a s p a c i n g w h i c h v a r i e s f r o m 197 f e e t
(Japan and Sweden) t o 240 f e e t ( B r i t a i n ) . Thus, no
e x i s t i n g f o r e i g n system c o u l d be d i r e c t l y a p p l i e d
w i t h o u t m o d i f i c a t i o n . F u r t h e r , t h e replacement
system would be c o n s t r a i n e d b y t h e e x i s t i n g s t r u c t u r e
c o n f i g u r a t i o n , t h e need t o keep t h e r a i l r o a d
o p e r a t i o n a l d u r i n g c o n s t r u c t i o n , and f u t u r e ease o f
maintenance. D u r i n g t h e t i m e t h e s t u d y was p e r formed, t h e system c r i t e r i a were d e f i n e d as
m a i n t a i n i n g e x i s t i n g w i r e h e i g h t and t r a c k speeds.
These l i m i t a t i o n s r e s u l t e d i n a recommendation t o
a d o p t a f i x e d t e r m i n a t i o n , v a r i a b l e t e n s i o n system.
The pantograph s t u d y i n d i c a t e d t h a t a l l e x i s t i n g
and proposed pantographs were c o m p a t i b l e w i t h t h e
e x i s t i n g system as w e l l as w i t h a l l o f t h e examined
proposed replacement systems. The system c a p a c i t y
and v o l t a g e l e v e l s t u d y f o u n d t h a t t h e e x i s t i n g and
proposed systems had adequate c a p a c i t y foi- p r e s e n t
and f u t u r e l o a d s . The maintenance s t u d y recommended
replacement o f t h e e x i s t i n g w i r e t r a i n , p e r f o r m i n g
more maintenance a t n i g h t when t r a c k t i m e i s more
r e a d i l y a v a i l a b l e and m o d i f y i n g some l o n g
92

These r e v i s i o n s prompted t h e r e c o n s i d e r a t i o n o f
a d o p t i n g a c o n s t a n t t e n s i o n t y p e o f c a t e n a r y system
w h i c h w o u l d be more c o m p a t i b l e w i t h h i g h speed
o p e r a t i o n s . B u t b e f o r e a d e c i s i o n would be made, a
careful evaluation o f the available constant tension
systems was performed. The c r i t i c a l f a c t o r s as t o
whether a system would be a d a p t a b l e where t h e span
l e n g t h s and a b i l i t y t o be i n s t a l l e d w i t h o u t i m p a c t i n g
t r a i n o p e r a t i o n s . A t t e n t i o n was f o c u s e d upon t h e
c a t e n a r y systems adopted b y B r i t i s h R a i l a t an e a r l y
s t a g e . The span l e n g t h was a nominal 240 f e e t , which
was t h e g r e a t e s t o f a l l systems e v a l u a t e d . I t was
f e l t t h a t t h i s c o u l d be e a s i l y extended t o t h e 300
f o o t s p a c i n g u t i l i z e d on t h e New Haven l i n e . F u r t h e r ,
B r i t i s h R a i l had c o n s i d e r a b l e e x p e r i e n c e i n m o d i f y i n g
c a t e n a r y systems w h i l e m a i n t a i n i n g normal o p e r a t i o n s .
I n o r d e r t o f u r t h e r assure t h e r a i l r o a d ' s engineering
and o p e r a t i o n s s t a f f t h a t t h e B r i t i s h system was
s u i t a b l e f o r use, M e t r o - N o r t h s t a f f a r r a n g e d a v i s i t
t o B r i t i s h R a i l . The v i s i t c o n c e n t r a t e d upon v i e w i n g
s i m i l a r c a t e n a r y systems i n o p e r a t i o n , d i s c u s s i n g
system performance w i t h maintenance s t a f f , and making
s i t e v i s i t s t o l o c a t i o n s w i t h topography s i m i l a r t o
t h e New Haven l i n e . Based upon t h e r e s u l t s o f t h i s
v i s i t , a d e c i s i o n w o u l d be made as t o whether t o
u t i l i z e a c o n s t a n t t e n s i o n system.
W h i l e t h e c h o i c e of a system was b e i n g r e v i e w e d ,
a n o t h e r f o c u s o f t h e s t u d y was t h e d e t e r m i n a t i o n o f an
optimum changeover l o c a t i o n . A t p r e s e n t , a l l New
Haven t r a i n s change from D.C. o p e r a t i o n b y means o f
an u n d e r r u n n i n g t h i r d r a i l t o A.C. o p e r t i o n , and v i c e
versa, a t Woodlawn, New York. T h i s l o c a t i o n , w h i l e
o r i g i n a l l y d i c t a t e d b y t h e r a i l r o a d b o u n d a r i e s , was
n o t an i d e a l one. I t was l o c a t e d upon an upgrade,
between two c l o s e l y a d j a c e n t i n t e r l o c k i n g s . As t h e
changeover o p e r a t i o n i n v o l v e s some c o a s t i n g , any
f a i l u r e t o make changeover c o u l d r e s u l t i n t r a i n s
b l o c k i n g an i n t e r l o c k i n g , c a u s i n g e x t e n s i v e d e l a y s t o

etc. p r i o r t o the contractor entering the property.

o t h e r t r a i n s . The o p t i m a l changeover l o c a t i o n would
be on a l e v e l , t a n g e n t t r a c k , a t a l o c a t i o n where a l l
t r a i n s would have s u f f i c i e n t speed t o p e r m i t c o a s t i n g .
Design E f f o r t s

-

For t h i s p r o j e c t , a w o r k i n g committee c o n s i s t i n g o f
members o f t h e maintenance, t r a n s p o r t a t i o n , s e r v i c e
p l a n n i n g , mechanical and c a p i t a l e n g i n e e r i n g d e p a r t ments was formed. T h i s committee met e v e r y two weeks
d u r i n g t h e d e s i g n s t a g e and p r o v i d e d c o n t i n u o u s
i n p u t t o t h e d e s i g n c o n s u l t a n t . Because o f t h e need
t o m a i n t a i n o p e r a t i o n s as c l o s e t o normal as p o s s i b l e ,
s t a g i n g o f t h e p r o j e c t was v e r y c r i t i c a l . E v e n t u a l l y
i t was r e a l i z e d t h a t a d e t a i l e d week by week schedule
o f t h e e n t i r e t h r e e y e a r p r o j e c t had t o be prepared.
T h i s schedule showed e v e r y i n d i v i d u a l segment o f
t r a c k , t h e p e r i o d o f t r a c k outage, t h e a l t e r n a t e
s e r v i c e r e q u i r e m e n t s , and any s p e c i a l r e s t r i c t i o n s .
O v e r a l l , i n excess o f 100 i n d i v i d u a l o p e r a t i o n s were
detailed f o r the project. Additionally a similar but
much s m a l l e r s e r i e s o f schedules had t o be prepared
t o c o o r d i n a t e AMTRAK s e r v i c e s as w e l l as o t h e r
Metro-North p r o j e c t such as c o n c r e t e t i e i n s t a l l a t i o n ,
t h e moveable b r i d g e r e h a b i l i t a t i o n program, d r a i n a g e
improvements, e t c . , a l l o f which would impact upon
t h e New Haven l i n e o p e r a t i o n s .

System Choice

The i t i n e r a r y o f t h e B r i t i s h R a i l v i s i t was an i n t e n s i v e f i v e day t o u r which covered e l e c t r i f i e d l i n e s
from London t o Crewe, t h e suburban l i n e s near Glasgow,
t h e new e l e c t r i f i c a t i o n near Edinburgh and Doncaster,
and a v i s i t t o t h e d e s i g n s t a f f i n Derby. The
p a r t i c i p a n t s o f t h i s t o u r were t h e a u t h o r , t h e Deputy
C h i e f Engineer-Power f o r Metro-North, and two
r e p r e s e n t a t i v e s o f t h e c o n s u l t a n t , Morrison-Knudsen.
Every e v o l u t i o n a r y t y p e o f c a t e n a r y system was seen,
b o t h i n o p e r a t i o n and under c o n s t r u c t i o n . E x t e n s i v e
d i s c u s s i o n s were h e l d w i t h maintenance and cons t r u c t i o n s t a f f concerning the r e l i a b i l i t y o f t h e
systems and t h e i r c o n s t r u c t i b i l i t y . A d d i t i o n a l l y ,
we wanted t o view t h e performance o f t h e c a t e n a r y
under severe weather c o n d i t i o n s . We t h o u g h t t h a t
A p r i l i n t h e B r i t i s h I s l e s would p r o v i d e s u i t a b l y
stormy days. U n f o r t u n a t e l y , t h e weather was most unB r i t i s h by b e i n g c l e a r and stunny d u r i n g o u r v i s i t .
We were, however, a b l e t o view a v i d e o f i l m e d d u r i n g
a storm o f a s e c t i o n o f a newly i n s t a l l e d c a t e n a r y
system near S a l t c o a t s on t h e Clyde e s t u a r y . Waves
generated by h u r r i c a n e f o r c e winds were b r e a k i n g
over an a d j a c e n t seawall and s a l t w a t e r was cascading
over t h e c a t e n a r y . D e s p i t e some s p e c t a c u l a r f l a s h overs, t h e system remained i n t a c t and i n s e r v i c e .

Another area where t h e o p e r a t i o n s p l a n n i n g approach
was u s e f u l was t h e d e t e r m i n a t i o n o f where t h e changeo v e r l o c a t i o n was t o be e s t a b l i s h e d . T h i s l o c a t i o n
had t o be determined e a r l y i n t h e d e s i g n e f f o r t , as
i t impacted t h e e x t e n t o f t h e t h i r d r a i l i n s t a l l a t i o n
t h e number o f D.C. s u b s t a t i o n s t o be p r o v i d e d and t h e
e x t e n t o f c a t e n a r y t o be removed. Once a p o t e n t i a l
l o c a t i o n was s e l e c t e d , s e p a r a t e s t u d i e s had t o be
performed t o d e t e r m i n e D.C. v o l t a g e d r o p which i n
t u r n determined t h e number, l o c a t i o n and c o n f i g u r a t i o n o f t h e D.C. s u b s t a t i o n s and c i r c u i t b r e a k e r
houses. Contingency s t u d i e s were a l s o performed t o
a s c e r t a i n whether t r a i n o p e r a t i o n s would be impacted
b y l o s s o f a s u b s t a t i o n due t o maintenance o r
u t i l i t y s u p p l y problems.

The o v e r a l l i m p r e s s i o n o f t h e v i s i t was t h a t a const a n t t e n s i o n c a t e n a r y system modelled upon one o f t h e
e a r l i e r B r i t i s h c a t e n a r y systems would be f u l l y
s a t i s f a c t o r y f o r use on t h e New Haven l i n e . An
e a r l i e r d e s i g n was chosen because o f t h e r o b u s t
nature o f i t s construction.
L a t e r designs i n c o r p o r a t e d l i g h t e r w e i g h t elements which would n o t have
been r e a d i l y a d a p t i b l e t o t h e h i g h e r t e n s i o n s r e q u i r e d
f o r t h e l o n g e r spans on t h e New Haven. F u r t h e r , t h e
l i g h t e r c o n s t r u c t i o n would l i m i t t h e o v e r a l l c u r r e n t
c a r r y i n g c a p a c i t y o f t h e c a t e n a r y system. W i t h t h e
s e l e c t i o n o f t h e t y p e o f c a t e n a r y system, d e t a i l e d
d e s i g n commenced.
Design E f f o r t s

-

A l o c a t i o n was agreed upon which i s a p p r o x i m a t e l y
2.5 m i l e s e a s t of t h e e x i s t i n g changeover l o c a t i o n .
I n o r d e r t h a t s u f f i c i e n t D.C. power w i l l be a v a i l a b l e
two new D.C. s u b s t a t i o n s a r e r e q u i r e d . I n o r d e r t o
keep c o s t s down t o a minimum, a m o b i l e s u b s t a t i o n
s u r p l u s from t h e Hudson-Harlem l i n e s w i l l be conv e r t e d i n t o a permanent u n i t w h i l e t h e o t h e r
s u b s t a t i o n w i l l u t i l i z e s u r p l u s apparatus f r o m
r e c e n t l y r e t i r e d s u b s t a t i o n s . F u r t h e r c o s t savings
w i l l a c c r u e b y t h e use o f 150 l b . c o n t a c t r a i l
s u r p l u s f r o m t h e Hudson-Harlem l i n e s c o n t a c t r a i l
program, use o f s t e e l channels f o r b r a c k e t mounting
i n p l a c e o f t h i r d r a i l t i e s , and t h e e l i m i n a t i o n o f
t h e need t o r e c o n s t r u c t t h e c a t e n a r y system i n t h e
area where t h i r d r a i l w i l l be i n s t a l l e d . T h i s
p a r t i c u l a r s e c t i o n i s m o s t l y l o c a t e d i n a c u t , which
has many low c l e a r a n c e b r i d g e s and c o n s i d e r a b l e
curvature. I t i s t h e worst s e c t i o n o f t h e catenary
system i n terms of maintenance d i f f i c u l t i e s and
o p e r a t i o n a l r e l i a b i l i t y . The c o s t s a v i n g s accrued
by e l i m i n a t i n g t h e c a t e n a r y a r e i n f a c t e s t i m a t e d
t o be g r e a t e r t h a n t h e c o s t o f t h e t h i r d r a i l
e x t e n s i o n , i n c l u d i n g t h e s u b s t a t i o n s . The enhancement o f o p e r a t i o n s i n t h i s area w i l l be a f u r t h e r
benefit.

Operations P l a n n i n g

P r i o r t o t h e commencement o f t h e p r o j e c t , i t was
decided t h a t r a t h e r than p r e p a r i n g d e t a i l e d d e s i g n
drawings o f t h e e n t i r e c a t e n a r y system, we would
prepare t y p i c a l drawings as system standards. The
c o n t r a c t o r would b i d t h e p r o j e c t on t h e b a s i s o f u n i t
q u a n t i t i e s developed d u r i n g t h e system s t a n d a r d
p r e p a r a t i o n and t h e n p e r f o r m t h e a c t u a l d e t a i l e d
l a y o u t s . T h i s method was u t i l i z e d on a p r e v i o u s
p r o j e c t - t h e replacement o f c o n t a c t r a i l on t h e
Hudson-Harlem l i n e s . The r e s u l t s o f t h e e x p e r i e n c e
had been v e r y f a v o r a b l e f o r t h e c o n t r a c t o r was r e q u i r e d t o become d u l l y f a m i l i a r w i t h t h e work b e f o r e
commencement o f c o n s t r u c t i o n . The c o n t r a c t o r i n
e f f e c t became r e s p o n s i b l e f o r m a t e r i a l q u a n t i t i e s
and t h e i r d e l i v e r y schedule. The o v e r a l l r e s u l t was
a h i g h e r q u a l i t y p r o j e c t w i t h fewer change o r d e r s .
Another l e s s o n l e a r n e d f r o m t h e p r e v i o u s p r o j e c t was
t h e need t o f u l l y c o o r d i n a t e t h e c o n s t r u c t i o n
s t a g i n g w i t h t h e r a i l r o a d ' s t r a n s p o r t a t i o n department
d u r i n g t h e d e s i g n process. T h i s way, b o t h t h e
t r a n s p o r t a t i o n department and t h e c o n t r a c t o r a r e
f u l l y aware o f t h e t r a c k outage r e q u i r e m e n t s p r i o r
t o b i d d i n g , and t h e t o t a l c o s t o f t h e work i n c o r p o r a t e s any i n e f f i c i e n c i e s , e x t r a crews, e t c . By
p a r t i c i p a t i n g i n t h e p l a n n i n g process, t h e t r a n s p o r t a t i o n department a l s o becomes f a m i l i a r w i t h t h e
p r o j e c t and can a d j u s t schedules, m o d i f y procedures,

Completion o f Design
Once t h e t y p e f o c a t e n a r y system was s e l e c t e d , a
changeover p o i n t l o c a t e d , and t h e p r o j e c t sequence
e s t a b l i s h e d , d e s i g n e f f o r t s were e s s e n t i a l l y t h o s e
r e q u i r e d t o p l a c e t h e necessary i n f o r m a t i o n on
s t a n d a r d drawings and w i t h i n a d e t a i l e d s p e c i f i c a t i o n . T h i s i s n o t t o say t h a t d e s i g n development
d i d n o t c o n t i n u e . Several i n s t a n c e s come t o mind.
Since t h e New Haven l i n e has h i g h l e v e l p l a t f o r m s
9

l o c a t e d on t h e outermost t r a c k s , s p e c i a l p r o v i s i o n s
have t o be made i n o r d e r t o p e r m i t passenger b o a r d i n g /
u n l o a d i n g when an o u t E r t r a c k i s t a k e n o u t o f s e r v i c e .
N o r m a l l y an aluminum b r i d g e p l a t e " e x t e n d i n g across
t h e t r a c k , s u f f i c i e n t f o r o n l y one door l e a f i s used.
T h i s t y p e o f b r i d g e p l a t e i s t o t a l l y unacceptable f o r
use d u r i n g peak p e r i o d s as i t - r e q u i r e s e x t e n s i v e
p e r i o d s o f t i m e t o p e r m i t a t r a i n t o s p o t i t s doors,
l o a d and unload passengers. Due t o t h e heavy
passenger l o a d i n g s on t h e New Haven l i n e , a minimum o f
16 doors on e i g h t c a r s had t o be accommodated a t each
s t a t i o n . The b r i d g e p l a t e s a l s o had t o be p o r t a b l e and
becapable o f easy movement by a two man crew.
P r o f i t i n g from t h e e x p e r i e n c e w i t h l i g h t w e i g h t f i b e r g l a s s g r a t i n g s used i n t h e new s u b s t a t i o n s , a f i b e r g l a s s b r i d g e p l a t e was designed which would be wide
enough f o r a c a r door, y e t would be e a s i l y handled b y
a two man crew. The use o f f i b e r g l a s would e l i m i n a t e
t h e need f o r p a i n t i n g w h i l e a l s o e l i m i n a t i n g any conc e r n s about e l e c t r i c a l c o n d u c t i v i t y .
Another i n t e r e s t i n g problem was encountered when t h e
p u l l e y assembly was b e i n g designed. Under t h e new
c a t e n a r y system, t h e messenger i s c a r r i e d o v e r each
s t r u c t u r e u s i n g a p u l l e y t o p e r m i t u n h i n d e r e d motion.
Due t o t h e 300 f o o t d i s t a n c e between s t r u c t u r e s , and
t h e need t o m a i n t a i n p r e d e t e r m i n e d sag and b l o w o f f
c r i t e r i a , a h i g h messenger t e n s i o n was s p e c i f i e d .
T h i s i n t u r n l e d t o a "Copperweld" messenger b e i n g
s p e c i f i e d , i n p l a c e o f a bronze messenger as used by
B r i t i s h R a i l . A q u e s t i o n a r o s e whether t h e p u l l e y
m a t e r i a l s h o u l d be h a r d e r o r s o f t e r t h a n t h e messenger.
A s e r i e s o f l i f e c y c l e t e s t s were undertaken w i t h
v a r i o u s m a t e r i a l combinations. A f t e r t h e e q u i v a l e n t
o f t e n y e a r s o p e r a t i o n , i t was d i s c o v e r e d t h a t a s o f t
p u l l e y wheel would deform w i t h r e s u l t i n g w i r e damage
t o t h e messenger. A h a r d wheel d i d n o t deform, b u t
d i d cause some f l a t t e n i n g o f t h e messenger s t r a n d s .
F i n a l l y , a l i n e g u a r d was p l a c e d o v e r t h e messenger,
and t h i s combined w i t h a h a r d p u l l e y wheel, r e s u l t e d
i n minimum d e f o r m a t i o n o f b o t h t h e wheel and messenger.
W h i l e t h e f i n a l elements o f t h e d e s i g n were b e i n g
e s t a b l i s h e d , d e t a i l e d c o s t e s t i m a t e s were prepared
f o r each element o f t h e p r o j e c t . A separate, p a r a l l e l ,
v a l u e e n g i n e e r i n g e f f o r t was performed t o d e t e r m i n e i f
any c o s t s a v i n g s c o u l d be r e a l i z e d by means o f d e s i g n
r e v i s i o n s . This e f f o r t e s t a b l i s h e d t h a t o t h e r design
o p t i o n s would e i t h e r have a g r e a t e r o v e r a l l c o s t , o r ,
w h i l e h a v i n g a l o w e r i n i t i a l c o s t , would a d v e r s e l y
a f f e c t operational r e l i a b i l i t y .
Once t h e f i n a l c o s t e s t i m a t e s were prepared, t h e
f i n a l p r o j e c t budget was approved and t h e p r o j e c t
e n t e r e d i n t o t h e b i d d i n g stage. A t t h e t i m e o f
w r i t i n g , t h e r a i l r o a d was i n t h e process o f s e e k i n g
bids f o r the reconstruction e f f o r t .
Conclusion
W i t h t h e c o m p l e t i o n o f t h e d e s i g n process, t h i s p r o j e c t now e n t e r s t h e c o n s t r u c t i o n stage. I t i s o u r
a n t i c i p a t i o n t h a t t h e e f f o r t s expended d u r i n g t h e
d e s i g n stages w i l l p e r m i t t h e C o n t r a c t o r t o accomplish
h i s d i f f i c u l t t a s k w i t h a minimum amount o f d i s r u p t i o n
t o t h e r i d i n g p u b l i c . We a r e c o n f i d e n t t h a t upon t h e
c o m p l e t i o n o f t h e r e c o n s t r u c t i o n , t h e New Haven l i n e
w i l l a g a i n have a c a t e n a r y system w h i c h w i l l be
second t o none.

94


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