Click for next page ( 58


The National Academies | 500 Fifth St. N.W. | Washington, D.C. 20001
Copyright © National Academy of Sciences. All rights reserved.
Terms of Use and Privacy Statement



Below are the first 10 and last 10 pages of uncorrected machine-read text (when available) of this chapter, followed by the top 30 algorithmically extracted key phrases from the chapter as a whole.
Intended to provide our own search engines and external engines with highly rich, chapter-representative searchable text on the opening pages of each chapter. Because it is UNCORRECTED material, please consider the following text as a useful but insufficient proxy for the authoritative book pages.

Do not use for reproduction, copying, pasting, or reading; exclusively for search engines.

OCR for page 57
APPENDIX B SURVEY OF CURRENT PRACTICE A survey of current practice was conducted among a group of traffic engineers who deal regularly with the design, implementation, and evaluation oftraffic-actuated signals. The results ofthe survey served as a database to NC~P Project 3-48. The objectives of the survey were to establish the range of operational configurations that should be considered in the research effort; to identify the timing plan design and analysis procedures that are commonly employed; and to determine the interest of individual agencies in providing data and/or sites for data collection. A copy ofthe two-page survey form is included In Figure BE The responses to the survey are sum- maIized in this appendix. The survey was sent to traffic operations and signal engineers of all 50 state Departments of Transportation and 3 ~ large cities across the country. Thirty states and six cities (47 percent) responded to the request for information. A summary of responses by agency is included in Table B-l, and a summary of responses by question is included in Table B-2. NUMBER OF SIGNALIZED INTERSECTIONS The 36 respondents to the survey indicated the number of signalized intersections by type of actuation control as follows: 4, 127 isolated sem~-actuated signals, 14,446 isolated fi~ly-actuated signals, and 19,979 coordinated actuated signals. States are responsible for an average of 164 (range Dom 0 to 1643) isolated sem~-actuated signals, 481 (range Dom 0 to 3000) isolated finely actuated signals, and 580 (range from 0 to 2700) coordinated actuated signals. It should be noted, however, that six of the states only reported information for coordinated actuated signals. Cities are responsible for an average of 37 (range Dom 12 to 87) isolated sem~-actuated signals, 195 (range Tom 14 to 270) isolated fiuDy-actuated signals, and 524 (range Tom 14 to 1400) coordinated actuated signals. The primary difference between state and city responses was that states maintain a larger number of isolated sem~-actuated and isolated fi~ly-actuated signals than cities. Appendix B.: Page 1

OCR for page 57
NCHRP PROJECT ~48 Sunrey of Traffic-Actuated Control Analysis Practice Agency Title Phone Contact Address Fax 1. Please indicate the procedures that are used commonly for design and analysis of timing parameters for traffic-actuated control. W~ely-used procedures are indicated by abbreviations: M= Manual computations, H=HCM (including all software products that implement the HCM methodology), T=TRANSYT P=PASSER Il. N=NETSiM, S=SOAP. Please circle all that apply. If you have developed your own written procedures, Lease circle the FAT and provide a copy. If you are using procedures other than those indicated, Lease describe them in the space provided, or give the program namers). If you do not carry out any design or analysis in a specific category, just leave the box blank. sooted, S e m i - ~ so! at ed, F u ~ ~ y-Actuated ~ T raffi c -Act u at ed Actuated Control Control Controllers in l I Coordinated Systems Numberof signalmen | l Intersections | M H T P N S A M H T P N S A | M H T P N S A Primary procedure(s) for determining operating parameters (extension interval, maximum,etc.) l l | M H T P N S A M H T P N S A | M H T P N S A Primary procedure(s) for estimating performance measures (delay, LOS etc.) 2. Percent of focal controllers ~NEMA], Other [ Type 170 or similar], 3. Are you able to provWe data pie'6 studies or video tape) or data collection sites that may be useful to this research project? ~ Yes] ~ No] 0/Ye will contact you if you answer Yes. 4. Please Indicate typica design configurations (i.e. those that represent more than 20 percent of your traffic-actuated approaches) on the attached sheets. These will be an Important source of Information for determining the range of operating conditions to be covered. Please reproduce the form ~ you have more than three configurations to report. 5. We would welcome your comments on what features and capabilities are most important In a traffic- actuated control analysis method. Please use a separate sheet. Appendix B.: Page 2

OCR for page 57
- ~ CL - -- c' Q Q CIS .~ Q 3 >I (D Be >I Q Q of O -1 In (D 3 ~ Q Q _ ~ . ~ ~1 . : cn . - o . ~ . O : C) . Cal Q tar . ~ 1111 111~- 111111 111: o o Cut 3 - _ ~ ~ E ._ ~ o ~ g Q ~ Q - 46 '_e ~ a_ :~ g : Hi e ~ Eve TO tj Q E ~ s . ~ ~ A,= 0 wO G) e4e ~8 ! ~ ~>. _ ~r Z . - o CtS a, 0 s e_ u, ege 1d Appendix B.: Page 3

OCR for page 57
.~ b ~ to _ i~ _ ~! .; ~D 4~ 04 b ~ ~ o.1l a, ii1 -3 o: ~ _ o ~ o Pa U) Cal bt l o o o o U] o on on EN o ~ .e ~ .~ Fin Appendix B.: Page 4 . 0 0 0 o k m ,- = m ran a ; ~ ._ O 0\ ~= u, =~ ~ co ~ Do Do C: ~ rl .; a ~ = x I_ ~0 Cal O O _ ,= a

OCR for page 57
T:~ ::TP7 :~ ~ :1~ ~ 1 11 ~:~ ~ ~tl J~ ~- J~ W 1361 ~ 1 1 1~ 1 1 1 13~1 1 1 1 ~1' 1 1 1 1 t~: J~ ~: ~ t~: Aim' ~ ~ ~ 11 :~- Appendix B.: Page 5

OCR for page 57
1 oo oo l i ! ~ ~- ~ : :l ' m.~O of m~ c,) - l ! . : . ~ Q) . . i i ~ ' ~ I ~ lo t c i ~-1'. AppenducB: Page 6 I 0 . ._ . ~ i ~ cot ~ 1 1 ~ 03 r' O | ~ N _ ~= a) C~J (D ~ O ~ _= (D-O U. ~ ~ Cat E E 1 W ~ ~ 0 0 0 ~ a ~;i i lo I A) ~ 1 1 o en j ~ ~ O ~ ~ O1 N

OCR for page 57
~ - ~ - v, - :' o In ret ~ E . - 3 ~Rio-= ~ o~ i ~ ~ a,) , 1~ 1 ~ ! Q e ~ ~ Ad 'c ~ ~ ! ! ' 1 ~ t; , , ~ __ =~ ~ ~ ~ ~ . ~ . is _Iz ~ ~ ~ . ~ ~ ~ I ~ (D ,, O Cr) ~1 O O ~ CD l _ I , ~ l ti i ~ E : ~ 1 ~ cn ~._ i I , o 1 l on I, ~ ! , 1 ~ ~ P ~l ~ 1 . . ~ 1 ~ ~ 1 1 a~1 1 Can 1 1 ~ =1 LU 1 ~1 1 o-`1 1 ~ 11 1 1 1 1 ~ ~ 1 1 ~1 I o E, 1 ~ ~ 1 11 1 21 1 ~1 I Al 1 ~1 11 E ~ Can 1 1 ~ ~ 1 1 '- 1 1 ~ ~ I_ 1 1o ~1 1 ~ [2 1 ~ It; 1 a' 1 1 ~ ~ 1 - cn 1a, 1 1 1 1 ~ ~ ~ ~ (~ ~ ~ UD ~ 0 ~ ~ ~ e ~ ~ ~ O u) ~ .,Y ,,,~. ~ ~ ~ 83 ~ C, ~ ~ p" ; ~ i " ; Appendix B.: Page ~

OCR for page 57
PROCEDURES FOR DETERMINING OPERATING PARAMETERS The primary procedures for determining operating parameters for the different types of actuated controllers are shown in Figures B-2, B-3 and B-4. For isolated sem~-actuated control, states use manual procedures 37 percent of the time, HCM procedures 33 percent of the time, SOAP 10 percent of the time, and other methods 20 percent of the time. Cities used manual procedures 56 percent of the time, HCM' PASSER II, SOAP, and other procedures each 11 percent of the time. Note, however, that ~ ~ percent represents the response Tom a single city. For isolated fully actuated control, states use manual procedures 34 percent of the time, HCM procedures 25 percent of the time, SOAP 14 percent of the time, and other procedures 27 percent of the time. Cities use manual procedures 55 percent of the time, and HCM, PASSER IT, SOAP, TRANSYT-7F, and other procedures each 9 percent of the time. In this category, 9 percent represents the response from a single city. For coordinated actuated signals, states use manual procedures 22 percent of the time, HCM procedures 19 percent ofthe time, PASSER IT 25 percent of the time, TRANSYT-7F 19 percent of the time, and other procedures 15 percent of the time. Cities use manual procedures 24 percent of the times HCM procedures 12 percent ofthe time, PASSER ~ 29 percent of the time, TRANSYT-7F 29 percent of the time, and other procedures 6 percent of the time. In this category, 6 percent represents the response from a single city. hn summary, the respondents reported that manual and HCM procedures are used 62 to 69 percent of the time for dete~Tnining isolated actuated signal operating parameters, but only 40 percent of the time for determining coordinated actuated signal operating parameters. It appears that as the level of complexity increases from isolated intersections to coordinated systems the use of manual and HCM procedures decreases, and the use of PASSER II and TRANSYT-7F increases. It should be noted, however, that none of the traffic signal models estimate all of the parameters for actuated control. Discussions with respondents suggest that this additional information is based on existing guidelines or controller manufacturers literature. Appendix B.: Page 8

OCR for page 57
14.1% 26.4% 3.7% 7.3% STATES CITIES 1 1.1 % STATES and CITIES 1 1 % 4.~% 23.2% 1 1.1 % 36.696 Mlanud [mind HCM TRANSYT PASSER II NETSIM ~ SOAP O OR Figure B-2. Primary procedures for determining operating parameters Isolated semi-actuated control - Appendix B: Page 9

OCR for page 57
1 r STATES ll CITIES 11.3% 9.1% ~*' STATES an ~ CITIES l 11% 1 1 ~ IUanual ^~ _ ~HCM 1 13~4% ~ 1 - 36.6% 1 1 [lo THAI YT I 3773%%.~% ~1 ~ 1 - 1 Figure B-3. Primary procedures for determining operating procedures Isolated, fully actuated control Appendix B.: Page 10 -

OCR for page 57
STATES 7.4% 3.2% 26.3 18.9% 18.9% CITIES 6.g96 29.496 23.6% 29.496 1 1 .8% STATES and CITIES 2.79[ ,% 3.696 20.Ei% ' 17.9% ~ Manual am] HCM TRANSYT PASSER II NETSIM SOAP O Odor Figure B-4. Primary procedures for determining operating parameters TrafO~c-actuated controllers in coordinated systems - Appendix B: Page 11

OCR for page 57
PROCEDURE FOR ESTIMATING PERFORMANCE MEASURES - The primary procedures for estimating performance measures for the different types of actuated con- trollers are shown in Figures B-5, B-6 and B-7. For isolated semi-actuated signals, states use manual procedures 6 percent of the time, HCM procedures 58 percent of the time, and NETS~, PASSER id, TRANSYT-7F, and other procedures each 8 percent of the time. Cities use manual procedures 29 percent ofthetime,HCMprocedures29 percent ofthetime, PASSERII 14 percent ofthetime, and other procedures 28 percent of the time. For isolated fully actuated signals, states use manual procedures 4 percent of the time, HCM procedures 54 percent ofthetime,NETSIM 11 percent ofthe time, and other procedures 31 percent of the time. Cities use manual and HCM procedures each 29 percent ofthe time, PASSERII 14 percent of the time, and other procedures 28 percent of the time. In this category, 20 percent represents the response from a single city. For coordinated actuated signals, states use manual procedures 6 percent of the time, HCM proce- dures 30 percent of the time, PASSER II 25 percent of the time, TRANSYT-7F 23 percent of the time, and other procedures 16 percent of the time. Cities use manual procedures 13 percent ofthe time, HCM procedures 13 percent of the time, PASSER lI 25 percent ofthe time, TRANSYT-7F 31 percent ofthe time, and other procedures 18 percent of the time. In this category, 13 percent represents the response Tom a single city. In summary, the respondents reported that manual and HCM procedures are used 57 to 64 percent ofthe time for estimating isolated actuated signal performance measures, but only 32 percent ofthe time for estimating coordinated actuated signal performance measures. Thus, similar to determining controller settings, it appears that, as the level of complexity increases from isolated intersections to coordinated systems, the use of manual and HCM procedures decreases, and the use of PASSER IT and TRANSYT-7F increases. Additionally, states use manual and HCM procedures more than cities, cities use PASSER II and TRANSYT-7F more than states, and NETSIM is used about 10 percent of the time when estimating performance measures of actuated controllers. Appendix B.: Page 12

OCR for page 57
STATES 8.3% 6.6% 1 1.1 % 8.3% rAl I CITIES 28.6% ~ / ~28.6% 14.3~~17 D 68.3% 28,8% STATES and CITIES 1 2.8% 7.7% 7.7% 10.3% 7.7% 63.8% ~ Menus mm HCM TRANSYT PASSER 11 NETSIM ~ SOAP i Other Figure B-5. Primary procedures for estimating performance measures Appendix B.: Page 13

OCR for page 57
STATES 1 3% 4.3% 2.2% I;4.3% CITIES 28.6% 28.6% 28.6% STATES and CITIES ~ 0.216 ~ 6.3% 216 / - 6.1% Manual PICA TRANSYT PASSER II NETSIM SOAP Other Figure B-6. Primary procedures for estimating performance measures Isolated, fully actuated control Appendix B.: Page 14

OCR for page 57
- - ~STATESl l CITIES 1.6~3% 6.3% 12.6% 12.~% 78` 83~ S 23.4%1 ~ STATES a nd CITIES | 79~. 21 Figure B-7. Primary procedures for estimating performance measures TrafD~c-actuated controllers in coordinated systems - AppendixB: Page 15

OCR for page 57
TYPICAL DESIGN CONFIGURATIONS A summary of the typical traffic-actuated design configurations is included in Table B-3. The summary contains information on principal applications, number of approaches, percent of signalized approaches, detector types and sizes, detector location and setback from the stop line, initial interval, allowable gap, maximum green, yellow plus all red, recall and coordinated phases. Loop sizes ranged from 6-feet by 6-feet to 6-feet by 60-feet with the longer loops more commonly found in left-turn lanes and the shorter loops more commonly found in through lanes. Detector set backs ranged from 0 to 60 feet, depending on approach speed and type of detector. Several agencies used multiple detectors on high speed (greater than 45 mph) approaches. Initial intervals ranged Dom 3 to 12 seconds for lefc-turn phases and from 4 to 17 seconds for through phases. Allowable gaps ranged from 0 to 5 seconds with the majority in the 2 to 4 second range. Maximum greens ranged from 15 to 40 seconds for lefc-turn phases to 20 to 90 seconds for through phases. Yellow plus all-reds were in the 3 to 6 second range. Recall was generally off or set to minimum, and when used, the coordinated phase serviced NEMA movements 2 and 6. Appendix B.: Page 16

OCR for page 57
- I' ~ C3 ~ to e=e .~! no '=~ ~ ~ ~ ~ a = by al d / ~ i' o It a E A,, P.~; ~j ~ 0 . A .~ -= .' .) vi _ ~ ~ ,~, 53 9~ ~= l _ _ _ ~ o X rip o o 3~= =~,8 ~ ~ z .t c' ~ 2 ~T~ to ~ o ~ o to ~ ~ ~ ~ ~ ~ ~ a. m~-,-~m t- t- O e'- Vim ~ _ by) ~7~v\~1` d" ~ ~ ~ = - ~ -- ooo o o 'a - - ~! a =~ ~! VL ~ : 0 ~ 0 ~ 0 ~ 0 in; a ~ ~ ~e - ~ a : z .5 .g A. ~ rip via . on }~! Ax O- v~ 0 o ~0 .~ '6 .g o 5 ~:; = = ~ z:z z~ :~+ ~ ~+ ~z ~ ~ ~ za z~ ~ z ~ z z z 1 1 1 1~ 1~ 11 ~ ~ ~ ;~ -~1' ~1^ ~1~ 1~ o-l~ o~ll = =~ -~o ~ ~ m~ m ~14 y~4 ~14 ~ ~ ~' y /~a a i~a ~ ~ }~% O - O \0 ~ ~ ~t ~ ~ ~ ~ .~ ~a, ~ , ~ I ~ 11 Appendix B: Page 17

OCR for page 57
~^~ | ~ a ~ ~ ~ hi. ~ > ~ ~ .~ .~ .~ .~ .g .: ~ 0 ~ 0 o<, on 0 ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ 3 ~ 1a ~ ~ ~ ~ ~ age ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~'3 /~ ~ ~ ~ ~ ~ ~ ,1 Jo ~ o o ~ ~: . . I Append~cB: Page 18 ~0 .s ~ 0 ~up _ ~ + + ~ $ ~0 _ - , ~ 0 rot , - o - ^ o o^ o ^ - No ~%c~ ~ -x o v~ ~o ~; a A C <5 a z z ~ ~ z ~ ~o . v+ v~, + + + + $ ~o + o~ ~ o~ o 0 ~ 0 o 0 c~ x ~ <~ r~ ~ r~, r~ ~0 a ~0 a ~0- O O O ~ ~ ~ ~^ O O O O^ V) i ~ ~X ~X~ ~ ~O ~0 =0 O ~ A ~ o ^ ~ ~ ~ _ = l ~ _ _ + + o - , . . ~ a 0D ~ O o 0 C`. .G ~ a ._ ~ 7 .! .d 1 . + ~ l> 0 0 '' ' _ ~ ~m ;} oS 0 ~ ~ ~1 1 N _

OCR for page 57
~i~1 I: | _ C 't3 _ ~g ~ o ~ to on ~ %,~: ,-m ~ d ~ ~ ~ ~ ~ _ .: ~ 1 i ~ ~ ~ ~S ~ ~ b ~ 3 u ~ 0 ._ .y TIC .~ .~ o ~ ~ ~4 .5 .8 g ~ ~ . ~o ~ ~ } _ .4 o ~ Hi, X 'D o X C`. . _ i~ Z ~ lt~O . \0 ED ~us ~ go go ~ ~.s .E ~ ~O In ~ _ ~ t_ ~ ~US Vat _. , o ~_~ _ ~ a ~ ~ ~ ~ .. ~ ~ r = = i' ~ - = r ~ ~ ~! ~} ~ ~ Or . XX =~ X ~ O V) ~ ~ ~ ~ O to 5 b ~ 3 7 1 z ~ O ~ O : : . . ~t . . us ~ _ _ ~- . 0 ', `` 0 8 v~ a ~ ~ ~1~1 11 |r~ 5 1 or~ s :'-il xx~ Ix' 1 11 1 1 11 ,~ ~ o ~,~ b,a~ Appendix B.: Page 19

OCR for page 57
je~ ~ - ~d do ~ ~ ~ - y; + + ~ ~ i. e ~ ~ ~ O x e x ~ ~ ~ x ~ '.~ ~ e ~ ~ e ,cD~ o 0 . e ~ e ~ You ~ ~ ~ 9 ~ ~ _ C' =- ~ 0 ~ C) ~ . C ~ Z z A In A) .E .5 - 00 X I~ 3 - o ~ o TIC C to ~E bT ~ i ~ C Appendix B.: Page 20 z z ~ z . .~ ~ ~ c l ~ C .' .y 0 ~ I - x x- ~ _ ~ ~ g ~ 3 3 3 m ', c, o, ~ =~^ X X X X ~o wS~ ~o _ - 1 T T ~ I .e _ C' Cq r kD + , ~ ~ .~ ~ d ~ > ~ ~ _ ~r~ . ~. I ~ r~ _ -' '9 X ~ ~ O ~ _ ~ j 8 8 ~ _ ~ ~ J ~ ~ C' .G o . l o ~m l ~ ~ ~, e ~ ~ :~0 3 ~ 1= =1 1~ ~1 1 1 1 1 1= ~ 1 - ~ 1 - 1 1 ~ 1- 1= 1~ ~ 18 ~ 1b ~ 1 1 18 1 1~ ~ 1= g 1< 0 ~ O ~ 2< r~ o o x .= u: 1 0 1 1 ~ ~o 1 1= ~1 1 1 10 o 1 L~ 13 ~ 1 1' z 1 1 1 1~ 1 1- ~ ~ 1= ~ 1 1~ ~ 1 14 ~ 1 1 1 1~ 1 1~! 1 11 19 11 1 11 1~ 11 1~ 11 1~ 11 1 11 1 11 1.6 11

OCR for page 57
+ ~ ~1 -~ ~ .~ ~ To ~ .~ ~ .~ 0- it .~ ~ .' ~ ~ ~ ~ . 1= ~ 1 ~ ~ 1~ =1 + m+ 1~ -1 ~ ~ 1~ 1~ =1~ Aim -1~ 1. l! 10 o 1 10 oft ~ 1= old ~ 10 10 ~1~ =10 olo 1. :~l. ~ It tie Tie nit ~I' DID ~ I' die his It ~I' I. ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ ~ : a 139~1~ Air ~1 1~ Ale ~ 13 1~31,5 1~ ~1~ 1 5 al }1~ 1% he 1- 1~1% 1~ }17 1 mf ~: ~ ~ rob m~ 1- 1' 1 1= 1~ 1- 1m Ix Ixo C= 1 GAIL. ? |5 1a | | .n ~ 1 ~ 8 I a I D Appendix B.: Page 21

OCR for page 57