daily menu » rate the banner | guess the city | one on oneforums map | privacy policy | DMCA | news magazine | posting guidelines

Go Back   SkyscraperCity > Infrastructure and Mobility Forums > Subways and Urban Transport

Subways and Urban Transport Metros, subways, light rail, trams, buses and other local transport systems



Global Announcement

As a general reminder, please respect others and respect copyrights. Go here to familiarize yourself with our posting policy.


Reply

 
Thread Tools
Old April 13th, 2012, 04:16 AM   #821
State of the Union
Registered User
 
Join Date: Jul 2010
Posts: 154
Likes (Received): 12

Quote:
Originally Posted by greg_christine View Post
The video illustrates the congestion that will exist at Metro Center with both the Blue Line and the Expo Line reversing there. A Blue Line train can be seen ahead of the Expo Line train at Pico. The Expo Line train ends up waiting in the tunnel because both platforms at Metro Center are already occupied.

I had expected the trains to have traffic signal priority on the western end of the Expo Line, or at least for the traffic lights to be synchronized with the trains. The video seems to show the trains waiting at most intersections.
I agree about signal priority, but it's a little slow now because it's new. For example, the Pasadena Gold Line has shaved nearly 10 minutes since it's opening. The Eastside Gold Line's flyover to Little Tokyo over US 101 has had it's speed increased as well. Point is: because it's new to the area and in operations, it will start off slow but over time it will seem more practical at Metro to increase speeds.
__________________
"BRT is a crock of shit, because it can mean any sort of improvement beyond a bus line in mixed traffic. BRT is joke, and until it's defined properly, should not even be considered." -JustinB
State of the Union no está en línea   Reply With Quote

Sponsored Links
Old April 13th, 2012, 01:03 PM   #822
rheintram
yeah, whatever
 
rheintram's Avatar
 
Join Date: Mar 2008
Posts: 3,598
Likes (Received): 924

I'm amazed how neat and beautiful all the stations and the entire line looks. About speed: It seems the trains accelerate very slowly, hence all the stops at intersections make the ride seem incredibly slow.
rheintram no está en línea   Reply With Quote
Old April 13th, 2012, 09:11 PM   #823
CCs77
Registered User
 
Join Date: Jul 2008
Posts: 1,115
Likes (Received): 2445

Quote:
Originally Posted by greg_christine View Post
The video illustrates the congestion that will exist at Metro Center with both the Blue Line and the Expo Line reversing there. A Blue Line train can be seen ahead of the Expo Line train at Pico. The Expo Line train ends up waiting in the tunnel because both platforms at Metro Center are already occupied.
It should't be a problem. They can either use one platform for blue line and the other for Expo or they could use that track interchange at the end of the platform and make the trains disembark at one platform, then go forward, and backward to change tracks and finally pick up passengers at the opposite platform.
I think they could have problems at the stretch at ground level shared by both lines, if they had trains coming every 3 minutes, (in both directions) won't almost left time for the traffic to pass at the intersections.
CCs77 no está en línea   Reply With Quote
Old April 13th, 2012, 09:28 PM   #824
Slartibartfas
Registered User
 
Join Date: Aug 2006
Location: Vedunia
Posts: 11,597
Likes (Received): 5958

Quote:
Originally Posted by rheintram View Post
I'm amazed how neat and beautiful all the stations and the entire line looks. About speed: It seems the trains accelerate very slowly, hence all the stops at intersections make the ride seem incredibly slow.
Could that be due to the insanely strict safety regulations in the US for trains? I mean because these regulations force trains to be much heavier than in Europe for example.
__________________
"Brexit means Brexit and we are going to make a Titanic success of it.”
Boris Johnson, Foreign Secretary, UK
Slartibartfas no está en línea   Reply With Quote
Old April 14th, 2012, 12:35 AM   #825
trainrover
:-x
 
trainrover's Avatar
 
Join Date: May 2006
Posts: 5,787
Likes (Received): 738

That American obligation you refer to applies to stock that share tracking with freight trains, I doubt it applies to this LRT.
__________________
.
hee hee
.
trainrover no está en línea   Reply With Quote
Old April 14th, 2012, 02:10 AM   #826
quashlo
Registered User
 
Join Date: Jun 2008
Posts: 14,835
Likes (Received): 3215

The commentary at 12:05 is disturbing...
Stupid pedestrians wanting to cross.

Anyways. regarding traffic signal priority, it seems like some of you are expecting traffic signal preemption, which is different than priority. Pre-emption is what freight trains, commuter rail, and emergency vehicles use, but it'd be extremely difficult (not to mention questionable from a safety standpoint) on a high-frequency, at-grade line in an urban environment like this, not the least reason being pedestrians needing to cross.

Instead, this is just a run-of-the-mill signal priority system, so the LRT phase is always given the same exact position in the signal cycle, but only activated when a train is detected. There's probably some reduction in green times for conflicting left-turn and cross-street movements, but the signal will still serve these conflicting movements first if they activated the detectors first. Of course, they could have taken it one step further and allowed the train to alter the signal phase sequence so that it would always get the next available phase, a solution that would have been closer to full preemption.
__________________
San Francisco
Japan 2013; Japan 2011
: Tōkyō I, II, III (Kamakura), IV (Yokohama), V; Ōsaka I (+Kyōto +Kōbe), II (Kyōto), III (Nara); Hiroshima; Fukuoka; Nagasaki; Kita-Kyushu + Shimonoseki; Nikkō
quashlo no está en línea   Reply With Quote
Old April 14th, 2012, 02:48 AM   #827
BoulderGrad
Registered User
 
BoulderGrad's Avatar
 
Join Date: Jun 2005
Location: Seattle, WA
Posts: 5,512
Likes (Received): 1177

Seattle light rail's at grade sections have a fairly complicated control that times signals as such that the train moves pretty smoothly through the area. Been on it several times to get to the airport and can only think of 1 time it had to wait and that was at the beginning of the at grade section.
__________________
My safety word is "Keep Going."
BoulderGrad está en línea ahora   Reply With Quote
Old April 14th, 2012, 04:47 AM   #828
Silly_Walks
Registered User
 
Join Date: Aug 2010
Posts: 3,974
Likes (Received): 836

Trams and buses in Amsterdam have a way (i think using a radio signal) to turn their light green (and the crossing ones red, of course).
Silly_Walks no está en línea   Reply With Quote
Old April 14th, 2012, 11:39 AM   #829
Falubaz
Registered User
 
Falubaz's Avatar
 
Join Date: Nov 2004
Location: Zielona Gora, Polska
Posts: 14,799
Likes (Received): 2940

Without priority the LRT is more like a big bus.
It was an error to build that line not segregated from the road traffic.
__________________
Zielona Góra - Ziemia Lubuska

₪₪₪Zielona Góra moim okiem₪₪₪ Zielonogórskie autobusy₪₪₪Port Lotniczy ZIElona Góra₪₪₪ BRT₪₪₪ścieżki rowerowe w ZG
₪₪₪[Świat] „Przebłyski pamięci”₪₪₪Moja Ameryka - nie tylko Stany
Falubaz no está en línea   Reply With Quote
Old April 14th, 2012, 01:21 PM   #830
Slartibartfas
Registered User
 
Join Date: Aug 2006
Location: Vedunia
Posts: 11,597
Likes (Received): 5958

Quote:
Originally Posted by trainrover View Post
That American obligation you refer to applies to stock that share tracking with freight trains, I doubt it applies to this LRT.
I see. But why do pretty much all light rails appear so massive? Is it just the US style to design them?
__________________
"Brexit means Brexit and we are going to make a Titanic success of it.”
Boris Johnson, Foreign Secretary, UK

Last edited by Slartibartfas; April 14th, 2012 at 01:39 PM.
Slartibartfas no está en línea   Reply With Quote
Old April 14th, 2012, 02:48 PM   #831
Nexis
Dark Wolf
 
Nexis's Avatar
 
Join Date: Aug 2007
Location: Along the Rails of North Jersey..
Posts: 15,684
Likes (Received): 17034

Quote:
Originally Posted by Slartibartfas View Post
I see. But why do pretty much all light rails appear so massive? Is it just the US style to design them?
US style...
__________________
My FLICKR Page < 54,100+ Photos of Urban Renewal , Infrastructure , Food and Nature in the Northeastern US
Visit the Reorganized New York City Section
My Photography Website
Visit the New Jersey Section
Nexis no está en línea   Reply With Quote
Old April 15th, 2012, 01:45 AM   #832
Suburbanist
on the road
 
Suburbanist's Avatar
 
Join Date: Dec 2009
Location: the rain capital of Europe
Posts: 27,532
Likes (Received): 21239

Quote:
Originally Posted by Slartibartfas View Post
I see. But why do pretty much all light rails appear so massive? Is it just the US style to design them?
The Expo Line is more like a pre-metro than a tramway. Trains hare anything but "light" by European standards as well.
__________________
YIMBY - Yes, in my backyard!
Suburbanist no está en línea   Reply With Quote
Old April 16th, 2012, 01:19 AM   #833
State of the Union
Registered User
 
Join Date: Jul 2010
Posts: 154
Likes (Received): 12

Quote:
Originally Posted by quashlo View Post
The commentary at 12:05 is disturbing...
Stupid pedestrians wanting to cross.

Anyways. regarding traffic signal priority, it seems like some of you are expecting traffic signal preemption, which is different than priority. Pre-emption is what freight trains, commuter rail, and emergency vehicles use, but it'd be extremely difficult (not to mention questionable from a safety standpoint) on a high-frequency, at-grade line in an urban environment like this, not the least reason being pedestrians needing to cross.

Instead, this is just a run-of-the-mill signal priority system, so the LRT phase is always given the same exact position in the signal cycle, but only activated when a train is detected. There's probably some reduction in green times for conflicting left-turn and cross-street movements, but the signal will still serve these conflicting movements first if they activated the detectors first. Of course, they could have taken it one step further and allowed the train to alter the signal phase sequence so that it would always get the next available phase, a solution that would have been closer to full preemption.
I know it's called preemption. However, I use them interchangeable because I use the literal sense of the word.

The bolded part isn't priority in any sense of the word. Blue Line on Washington Bl is what I'm talking about. No matter what phase or how far the traffic signal is in the cycle, conflicting movements are immediately turned red and the train is given a green whether it is early or late.(Granted, during rush hours, the trains come so often that some trains have to wait because there has to be atleast one full cycle before the next train can past.

Signal sync is useless. If the train hits the stretch of track at the right time and pace, great. However, come too early or if there's a slight delay you will have to wait for each light.
__________________
"BRT is a crock of shit, because it can mean any sort of improvement beyond a bus line in mixed traffic. BRT is joke, and until it's defined properly, should not even be considered." -JustinB
State of the Union no está en línea   Reply With Quote
Old April 16th, 2012, 09:55 PM   #834
trainrover
:-x
 
trainrover's Avatar
 
Join Date: May 2006
Posts: 5,787
Likes (Received): 738

Quote:
Originally Posted by quashlo View Post
The commentary at 12:05 is disturbing...
Stupid pedestrians wanting to cross.
Hee hee -- Did you check out how its launcher's comments end?
...

The train operator spends extreme caution on safety, carefully looking at the surroundings and slowing down for any hazards near the tracks.

Interestingly, at the Expo Line - Blue Line junction, the northbound Expo Line train waits for a northbound Blue Line train. The Expo Line train then waits for two trains at the platforms of the 7th Street / Metro Center Station. This train congestion results in a 9-minute delay to the schedule, with the trip taking 34 minutes instead of the scheduled 25 minutes.


What gets me is that the LRT's signal went Stop before the one designated for the traffic travelling in the same direction alongside it did
__________________
.
hee hee
.

Last edited by trainrover; April 16th, 2012 at 10:02 PM.
trainrover no está en línea   Reply With Quote
Old April 16th, 2012, 10:04 PM   #835
Slartibartfas
Registered User
 
Join Date: Aug 2006
Location: Vedunia
Posts: 11,597
Likes (Received): 5958

Quote:
Originally Posted by Suburbanist View Post
The Expo Line is more like a pre-metro than a tramway. Trains hare anything but "light" by European standards as well.
I am well aware that this light rail is pretty much like a German Stadtbahn.

To unleash the full potential the Expo line seems to need some well designed crossing prioritizing I guess.
__________________
"Brexit means Brexit and we are going to make a Titanic success of it.”
Boris Johnson, Foreign Secretary, UK
Slartibartfas no está en línea   Reply With Quote
Old April 17th, 2012, 08:28 AM   #836
Fan Railer
Registered User
 
Join Date: Dec 2010
Posts: 658
Likes (Received): 566

Quote:
Originally Posted by Slartibartfas View Post
I see. But why do pretty much all light rails appear so massive? Is it just the US style to design them?
They still fall under the FRA safety regulations which require certain designs to ensure safety for passengers in the event of crashes.
Fan Railer no está en línea   Reply With Quote
Old April 17th, 2012, 09:24 AM   #837
Woonsocket54
PC LOAD LETTER
 
Woonsocket54's Avatar
 
Join Date: May 2005
Location: East Millinocket, Maine
Posts: 5,644
Likes (Received): 5751

They should have quadruple-tracked from Julian Dixon to Flower/Wash Junction to avoid Expo and Blue line trains sharing tracks. It wouldn't have been that expensive and the line would have opened last year.
Woonsocket54 no está en línea   Reply With Quote
Old April 18th, 2012, 12:09 AM   #838
Slartibartfas
Registered User
 
Join Date: Aug 2006
Location: Vedunia
Posts: 11,597
Likes (Received): 5958

Quote:
Originally Posted by Fan Railer View Post
They still fall under the FRA safety regulations which require certain designs to ensure safety for passengers in the event of crashes.
Does this have a significant impact on vehicle weight (compared to Europe for example)? What sort of safety features are that?
__________________
"Brexit means Brexit and we are going to make a Titanic success of it.”
Boris Johnson, Foreign Secretary, UK
Slartibartfas no está en línea   Reply With Quote
Old April 20th, 2012, 12:28 AM   #839
Sky Harbor
Green + Maroon = Blue. :D
 
Sky Harbor's Avatar
 
Join Date: May 2008
Location: Warsaw/Quezon City/Marinduque/Pittsburgh
Posts: 7,909
Likes (Received): 59

If I'm not mistaken, U.S. train vehicles are heavier than their European counterparts.
__________________
Help me get to Open Source Bridge 2014: donate today! :D
http://www.gofundme.com/wikimagic
Sky Harbor no está en línea   Reply With Quote
Old April 21st, 2012, 04:35 AM   #840
greg_christine
Registered User
 
greg_christine's Avatar
 
Join Date: Jan 2004
Location: Smithfield, VA
Posts: 1,008
Likes (Received): 142

Congratulations to Los Angeles on the imminent opening of the Aqua/Expo Line!

I was in Pasadena earlier this week, and traveled the rail network all the way to Redondo Beach via the Gold, Red/Purple, Blue, and Green Lines. I regret that I missed the opening of the Aqua/Expo Line by less than two weeks.

My visit made me a fan of the Gold Line. While stuck in slow traffic on I-210, I witnessed a train fly past the cars, and I wished I could have taken the train to my destination that day.



I'm not such a fan of the Blue Line. On a southbound train, I was panhandled once. On the northbound return trip, I was panhandled twice more. I've been panhandled near transit stations in other cities, but not on the trains.

I witnessed a transit police ticket checking operation at the Union Station terminus of the Red/Purple Line. The operation seemed inept. A group of officers stood near the center of the platform. One of the officers stopped me to examine my ticket, but he ignored the folks who fled out the door at the far end of the train. Just based on who was running, the officers should have been able to guess which passengers did not have tickets, and they should have placed other officers near the platform exits to intercept them. Perhaps the purpose of the operation was to scare the people without tickets rather than catch them.
greg_christine no está en línea   Reply With Quote


Reply

Tags
los angeles

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Related topics on SkyscraperCity


All times are GMT +2. The time now is 10:33 PM.


Powered by vBulletin® Version 3.8.11 Beta 4
Copyright ©2000 - 2018, vBulletin Solutions Inc.
Feedback Buttons provided by Advanced Post Thanks / Like (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.

vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.

SkyscraperCity ☆ In Urbanity We trust ☆ about us | privacy policy | DMCA policy

tech management by Sysprosium