Capacities of Unsignalized Intersections Under Mixed Vehicular and Nonmotorized Traffic Conditions

Transcription

1 apaces of Unsgnalzed Inersecons Under Mxed Vehcular and onmoorzed Traffc ondons Hayuan L, We Deng, Zong Tan, and Pefeng Hu Unsgnalzed nersecons conss of hree ypes wo-way sopconrolled, all-way sop-conrolled, and unconrolled nersecons all wh dfferen prory relaonshps beween raffc movemens accordng o raffc laws. A conflc echnque mehod was used o develop capacy models for he hree ypes of unsgnalzed nersecons under mxed raffc condons nvolvng vehcular, bcycle, and pedesran movemens. Wh feld daa colleced from several unsgnalzed nersecons, he model parameers were calbraed by a comparson analyss of raffc condons n hna and were modfed on he bass of acual raffc condons. The capaces obaned by he proposed models mached well wh he observed capaces and he capaces calculaed by convenonal mehods, boh of whch verfed he effecveness of he proposed models. The models proved o be valuable ools for deermnng capaces of vehcular movemens a unsgnalzed nersecons. Two-way sop-conrolled (TW, all-way sop-conrolled (AW, and unconrolled nersecons are he mos common unsgnalzed nersecon conrol ypes. The prory relaonshps beween raffc movemens are dfferen a hese hree ypes of unsgnalzed nersecons accordng o he raffc laws of dfferen counres. A sgnfcan amoun of effor has been devoed o analyzng capaces of unsgnalzed nersecons. Gap accepance heory s a convenonal mehod used o esmae he capaces of TW nersecons accordng o Harders (, egloch (, Grossmann (, and he Hghway apacy Manual (HM (. Brlon and Wu ( presened a heorecal mehod for dervng capaces of TW nersecons based on he raffc conflc echnque. Brlon and Mlner (6 provded a modfed mehod o calculae capaces of TW nersecons. Heber ( esmaed capaces on he bass of average deparure headways a AW T-nersecons. Rchardson ( developed a capacy model n erms of he servce me a AW nersecons. In he HM (, an emprcal approach was appled o deermne capaces of AW nersecons based on a regresson of feld daa. In he HM (, an exended model of Rchardson s work ( was used o calculae capaces for AW nersecons. The AW model ncorporaed n he HM ( was an approach-based model. Wu ( presened a movemen-based model for calcu- H. L, Z. Tan, and P. Hu, Deparmen of vl and Envronmen Engneerng, Unversy of evada, Reno, Reno, V. W. Deng, Transporaon ollege, ouheas Unversy, o., palou, 6, anng, hna. orrespondng auhor: H. L, hayuanl@homal.com. Transporaon Research Record: Journal of he Transporaon Research Board, o., Transporaon Research Board of he aonal Academes, Washngon, D..,, pp.. DOI:./-6 lang capaces of AW nersecons based on he mehod of addon-conflc-flow. However, he prevous models and mehods gave lle or no consderaon o nonmoorzed movemens, and raffc characerscs a unsgnalzed nersecons wh only vehcular movemens dffer from hose wh vehcular and nonmoorzed movemens. A research proec sponsored by he Mnsry of cence and Technology n hna was conduced by he auhors o assess capaces of unsgnalzed nersecons under mxed raffc condons. As a resul, models were developed o esmae capaces of vehcular movemens a TW, AW, and unconrolled nersecons on he bass of he feld daa and a raffc conflc mehod. PRIORITY RELATIOHIP OF TRAFFI MOVEMET Accordng o he raffc laws n hna, he prory relaonshps beween raffc movemens a TW, AW, and unconrolled nersecons can be depced as follows:. A TW nersecons, he prory rank of vehcular movemens s shown n Table.. Vehcular movemens a AW nersecons are consdered o be equal n prory for deparure.. A unconrolled nersecons (unsgnalzed nersecons whou raffc sgns, vehcles arrvng a an nersecon approach are requred o yeld o he vehcles on he rgh-sde approach; hrough vehcles have a hgher prory han lef-urn or rgh-urn vehcles; and rgh-urn vehcles have o gve way o conflcng lef-urn vehcles. The prory relaonshps beween vehcular movemens and nonmoorzed movemens are ruled as follows: nonmoorzed road users have o yeld o hrough vehcles; vehcles arrvng a an nersecon have a hgher prory han nonmoorzed road users; lef-urn or rgh-urn vehcles deparng from an nersecon are requred o yeld o nonmoorzed road users. OFLIT TEHIQUE METHOD apaces of Vehcular Movemens n a Deparure equence nce he prory relaonshps beween raffc movemens are dfferen a hese hree ypes of unsgnalzed nersecons, he vehcles of dfferen movemens have o pass hrough correspondng conflc areas one afer anoher accordng o prory rules. As a resul, a conflc group (a deparure sequence s formed n he same conflc area. Each

2 Transporaon Research Record TABLE Prory Rank of Vehcular Movemens a TW Inersecons Rank Prory Vehcular Movemens Absolue prory Maor sree hrough and rgh-urn vehcles Yeldng o vehcles of he frs rank Maor sree lef-urn vehcles and mnor-sree rgh-urn vehcles Yeldng o vehcles of he frs and second ranks Mnor sree hrough vehcles Lowes prory Mnor sree lef-urn vehcles conflc group nvolves many conflc pons ha are close o each oher and can be occuped by only one vehcle a a me. One conflc group usually conans raffc movemens from several drecons (Fgure. Vehcles of a parcular movemen can pass hrough he conflc area f s no occuped by oher movemens of equal or hgher prory. I s assumed ha every vehcle of movemen occupes he conflc area for exacly B seconds. All movemens n a conflc group can use s all ogeher n an hour. If all vehcular movemens occur n undersauraed condons, and he volume of movemen, Q, s known, he probably of movemen occupyng he conflc area s gven by he followng equaon (: P P B probably ha he conflc area s occuped by movemen, Q volume of movemen, and B average me of a vehcle crossng conflc areas for movemen. The probably ha he conflc area s no occuped by vehcles of movemen, P, s gven as follows: P PB ( For a wang vehcle, he conflc area s also occuped f a vehcle of a hgher prory movemen s approachng he conflc area. Assumng ha he gaps of hgher prory movemens follow an exponenal dsrbuon, he probably ha he conflc area s no occuped by an approachng vehcle of hgher prory movemen s esmaed by he followng equaon (6: P B a B Qa e, ( P a s he probably ha he conflc area s no occuped by vehcles of hgher prory movemens n advance of her arrvals, and a s he average me of an approachng vehcle occupyng he conflc area n advance of s arrval. Vehcles of movemen can only ener he conflc area f boh of he above condons are me smulaneously. The probably ha boh condons are me s gven as follows n Equaon : ( ( P PB Pa ( The maxmum capacy of movemen, max, s he maxmum number of vehcles ha can pass hrough he conflc area whou beng mpaced by oher movemens: max, ( B Accordng o Brlon and Mlner (6, he acual capacy of movemen under undersauraed raffc condons can be expressed as follows: P max ( 6 Dk capacy of movemen, k number of conflc areas relaed o movemen, and D k se of conflc movemens n he conflc group k. If raffc flows of all vehcular movemens havng he same prory exceed her capaces, referred o as fully sauraed condons, all vehcular movemens are supposed o have he same average capacy. The servce me of hgher prory movemens should be subraced from he oal me n a conflc area. The capacy of vehcular movemen can hen be obaned by he followng equaon: ( s Bs s Du De B ( average capacy, Q s volume of hgher prory movemen s relaed o movemen, Bs average me of a vehcle crossng conflc areas for movemen s, D u se of hgher prory movemens relaed o movemen, and D e se of equal prory movemens relaed o movemen. If raffc flows of no all vehcular movemens havng he same prory are up o sauraed condons, referred o as parally sauraed condons, he remanng capaces of undersauraed vehcular movemens can be dsrbued by oher sauraed vehcular movemens. Accordng o Wu ( he capacy of a sauraed vehcular movemen wll be as follows: FIGURE Traffc movemens pass hrough conflc area. ( B Dm n Bk k Dm B ( D m s he se of undersauraed movemens n a conflc group.

3 L, Deng, Tan, and Hu The capacy of vehcular movemen n a conflc group should be he maxmum flow rae under he condons of undersauraed, parally sauraed, and fully sauraed raffc flows: apaces of Vehcular Movemens n More han One Deparure equence All vehcles have o decelerae or sop a enrances o unsgnalzed nersecons, excep for rank movemens a TW nersecons. When all conflc areas are no occuped by oher movemens of equal or hgher prory, vehcles can hen ener an nersecon. Fgure shows wo cases n whch movemen he red arrow, has o pass hrough wo conflc areas, A and B. If all vehcular movemens n he deparure sequences are n undersauraed raffc condons, he probably ha all conflc areas are free of oher movemens of equal or hgher prory s he produc of probables of each conflc area no beng occuped. Accordng o Brlon and Mlner (6, he capacy of movemen can be esmaed as follows: max P k ( P k s he probably ha conflc area k s no occuped by oher movemens of equal or hgher prory for movemen, and D n s he se of conflc areas ha movemen needs o pass hrough. If all vehcular movemens relaed o movemen n he deparure sequences are under sauraed raffc condons, hen he capacy of movemen can be gven as follows: ( s Bs s Du B De n max P, max ( s Bs B s Du De, Bk k De, k... ( s Bs ( B s Du De, B ( n Dn B k D n Bkh B k Dn, h k k Dn ( n Bkh average me ha vehcles of movemen h occupy conflc area k relaed o movemen, B A FIGURE Traffc Movemen mus pass hrough wo conflc areas. B k A B ( ( n number of conflc areas relaed o movemen, and k capacy of movemen passng hrough conflc area k. In fac, f he capacy of movemen passng hrough conflc area k s adoped as he value of k under he condons of parally sauraed or fully sauraed raffc flows, hen he raffc condons of parally sauraed movemens have been aken no accoun n he calculaon process. The capacy of movemen n several deparure sequences should be he maxmum flow rae n hese hree cases. APAITY MODEL FOR UIGALIZED ITERETIO apacy Model Whou onmoorzed Movemens When nonmoorzed road users are no consdered, a four-leg unsgnalzed nersecon may conan up o vehcular movemens. I s necessary o specfy he conflc areas and conflc movemens relaed o each movemen. Assumng ha each vehcular movemen has s own raffc lane on all approaches, more han one conflc area mus be examned for each movemen. As seen n Fgure hese conflc areas can be arranged no egh conflc groups accordng o he graph heory and conflc ypes (. Vehcles a an unsgnalzed nersecon have o pass hrough several conflc areas o cross he nersecon. In undersauraed raffc condons, vehcles of movemen can ener he nersecon only when all relevan conflc areas are free of oher movemens of equal or hgher prory. In such a case, he capacy of movemen wll be as follows: max P k ( Then he capacy of movemen should be he maxmum flow rae under he condons of undersauraed, parally sauraed, and fully sauraed raffc flows: max k Dn k D n max max k Dn max ( n k k D n ( n k k D n P P k k wh ( s Bs s Duk B Dek s Bs ( B s D uk k max Dek, Bh h Dek, h..., ( ( s Bs B s Duk Dek, B B B ( ( (

4 Transporaon Research Record k onflc group Traffc movemen (a (b FIGURE Traffc movemens and conflc groups a TW nersecon whou nonmoorzed road users. D uk se of hgher prory movemens n conflc group k relaed o movemen, Bs average me of a vehcle crossng conflc areas for movemen s, and D ek se of equal prory movemens n conflc group k relaed o movemen. apacy Model wh onmoorzed Movemens In addon o he vehcular movemens, a four-leg unsgnalzed nersecon can have up o egh pedesran movemens and bcycle movemens. The four rgh-urn bcycle movemens can be gnored, however, due o her lack of conflcs wh oher movemens. To ake all he oher movemens no accoun a he nersecon, s necessary o specfy he conflc areas and conflc movemens relaed o each movemen. Assumng ha each vehcular movemen has s own raffc lane on all approaches and each nonmoorzed road user has hs or her own pah, more han one conflc area has o be examned for each vehcular movemen. All conflc areas can be arranged no conflc groups a an unsgnalzed nersecon wh pedesran and bcycle movemens arranged accordng o graph heory and conflc ypes (. onflc groups and relevan raffc movemens are shown n Fgures and and are lsed n Table, n whch hrough denoe vehcular movemens; F hrough F denoe pedesran movemens; and R hrough R denoe bcycle movemens. Accordng o Brlon and Mlner (6, a so-called conflc marx s used o express he prory relaonshps based on raffc laws. If one movemen conflcs wh anoher one, he correspondng cell of he marx s gven a value of A. By defnon, A f movemen has hgher prory han movemen ; A for movemen yeldng o movemen ; and A. for movemen and movemen havng he same prory. nce conflcs among pedesrans and bcyclss are mnor, boh conflc ypes are no aken no accoun. In undersauraed raffc condons, vehcles of movemen can ener he nersecon only when all relevan conflc groups are free of oher movemens of equal or hgher prory. In such a case, he capacy of vehcular movemen wll be as follows: F F R R F F R R 6 R R F F R6 R F6 F F F R R k onflc group F F Traffc movemen R F6 R R F 6 R F F 6 R R6 (a (b FIGURE Traffc movemens and conflc groups a TW nersecon wh nonmoorzed road users.

5 L, Deng, Tan, and Hu R R6 R R6 R R6 R 6 R (a R (b R R R (c (d FIGURE onflc Groups, 6,, and. max P k k D n B k D n A l cell value of conflc marx beween movemen l and movemen, A r cell value of he conflc marx beween movemen r and movemen, Q l volume of movemen l, Bl average me of a un of movemen l crossng conflc areas, Q r volume of movemen r, ar average me of a vehcle occupyng conflc areas n advance of s arrval for movemen r, and D sk se of hgher-prory vehcular movemens n conflc group k relaed o movemen. For vehcular movemen, he servce me of hgher prory movemens mus be subraced from he oal me. The capacy of vehcular movemen should be he maxmum flow rae under he condons of undersauraed, parally sauraed, and fully sauraed raffc flows. e l Dk Ar r ar ( r D sk, k D n ( n B k D n k max B k D n ( ArQr ar, r D e sk, k D n ( A l Ql Bl l Dk ( Al l Bl ( 6 ( wh k ( A g g Bg ( A r r Br g Dpb r Dsk B Dek ( A g g Bg A r r Br ( B g Dpb r Dsk Bh h Dek, h max Dek,... ( A g g Bg g D pb ( A r r B r ( B r Dsk Dek, ( B D pb se of pedesran and bcycle movemens n conflc group k relaed o movemen, Br average me of a vehcle crossng conflc areas for movemen r, A g cell value of he conflc marx beween pedesran or bcycle movemen g and vehcular movemen, Q g volume of pedesran or bcycle movemen g, and Bg average me of pedesrans or bcyclss crossng conflc areas for pedesran or bcycle movemen g. Equaon s a general model for esmang capaces a hese hree ypes of unsgnalzed nersecons. The second par of Equaon can be used drecly o calculae he capaces of TABLE onflc Groups and Traffc Movemens k Veh Ped Bke k Veh Bke k Veh Ped Bke,, F R, R,,, R, R, R,, F R, R, F R, R6 6,,, R, R, R6,, 6 F R, R, 6, F R R,,, R, R6, R,, F6 R R6,, F R, R,,, R, R6, R,, F R, R OTE: raffc movemens nvolved n conflc group k, veh vehcular movemens, ped pedesran movemens, and bke bcycle movemens.

6 Transporaon Research Record TW nersecons. A AW nersecons, snce all vehcular movemens have he same prory, he par of hgher prory vehcular movemens n Equaon can be gnored, and he probably ha conflc areas are no occuped by hgher prory vehcles n advance of her arrvals should be cancelled n he second par of Equaon. GROUP ALULATIO OF OMOTORIZED MOVEMET Pedesrans and bcyclss usually pass hrough he nersecons group by group. Thus, group volume and group occupaon me of pedesran and bcycle movemens should be adoped n he models. Group alculaon of Pedesran Movemens In order o deermne group volume and group occupaon me, he analys mus observe n he feld or esmae he group sze of pedesrans wang o cross he nersecon (: wh c Vpv A Q ( c group sze of pedesrans wang o cross he nersecon for pedesran movemen, V p flow rae of pedesran movemen, V pv oal flow rae of vehcular movemens conflcng wh pedesran movemen, c average me of pedesrans crossng conflc areas for pedesran movemen, W B oal wdh of one-way lanes and bcycle pahs, and P average walkng speed. The spaal dsrbuon of pedesrans can hen be obaned by usng Equaon (. If no plaoon s observed, spaal dsrbuon of pedesrans s assumed o be : c WB +. ( p p c pv c V p e + V pv e ( V + V e V p V pv ( c P ( D k V ( p pv c n. W E + ( p s he spaal dsrbuon of pedesrans for pedesran movemen and W E s he effecve crosswalk wdh. Group occupaon me of pedesran movemen, Gp, can be deermned as follows: + ( Gp c p ( ( V Group flow rae of pedesran movemen, n p, can be expressed as follows: n Group alculaon of Bcycle Movemens mlar o he analycal mehod for pedesrans, group volume and group occupaon me of bcycle movemens can be obaned. The group sze of bcyclss wang o cross he nersecon can be obaned hrough feld observaon or esmaon mehods: wh b V A Q bv Dk, k Dn s group sze of bcyclss wang o cross he nersecon for bcycle movemen, V b flow rae of bcycle movemen, V bv oal flow rae of vehcular movemens conflcng wh bcycle movemen, b average me of bcyclss crossng conflc areas, and b average speed of bcyclss. The spaal dsrbuon of bcyclss can hen be obaned as follows: wh Wb D b bf ( p s WB +. ( 6 b bf Vp n ( Vb b V V bv b b e + V bv e ( V + V e V b V bv ( b b ( s n W + ( W D ( Z b p b bv b spaal dsrbuon of bcyclss for bcycle movemen, W b acual wdh of bcycles occupyng he road when bcyclss are crossng he nersecon, D b average acual wdh of a bcycle occupyng he road, bf plaoon sze of bcyclss a he frs row, W Z effecve wdh of he bcycle pah, and D average mmoble wdh of a bcycle occupyng he road. Group occupaon me of bcycle movemen, Gb, can be deermned as follows: + ( Gb b b ( ( (

7 L, Deng, Tan, and Hu Group flow rae of bcycle movemen, n b, can be expressed as follows: n b Vb n ( b DATA OLLETIO AD MODIFIED OFLIT MATRIX Daa ollecon Traffc daa used n hs sudy were obaned by vdeoapng TW and four-leg unconrolled nersecons n Wuhu and Maanshan, hna. The nersecons seleced for observaon had dfferen confguraons and relavely heavy raffc of all knds of road users. All vdeos were aped durng he mornng (6: o : a.m. and evenng (: o : p.m. peak hours for fve weekdays a each nersecon. The daa were gahered by a vdeo-mage sysem and were analyzed by a program package, P. The capaces of vehcular movemens were observed a he nersecons by usng Kye s mehod (. The model parameers can be calbraed by he feld daa, and he models can also be evaluaed by comparng he observed capaces wh he calculaed capaces. In addon, an mporan aspec of he survey was o observe he behavors of vehcular drvers and nonmoorzed road users n he cases of conflcs and o deermne he ypes and proporon of prory rule reversals. Modfed onflc Marx nce no all road users always have a clear dea abou he prory herarchy a hese hree ypes of unsgnalzed nersecons, hey do no usually compleely comply wh he prory rules. The feld daa showed many cases of prory reversal. The observed prory of raffc movemens can be refleced by a modfed conflc marx. The modfed conflc marx expresses o whch degree, A, he movemen has prory over movemen. These A values are rounded averages over all observed nersecons. The modfed conflc marx ndcaes ha all he prores are lmed n real-lfe suaons a unsgnalzed nersecons. nce he lmed prory behavors sgnfcanly nfluence he capaces and delays of raffc movemens, he assumpon ha he raffc prory rules are obeyed compleely s unpraccal a unsgnalzed nersecons. The acual capaces of vehcular movemens can be obaned by usng he modfed conflc marx n he proposed models. ALIBRATIO OF MODEL PARAMETER Before he proposed models can be used o calculae he capaces of vehcular movemens a hese hree ypes of unsgnalzed nersecons, s necessary o calbrae he values of he model parameers for dfferen vehcular movemens. nce conflc areas canno be paroned clearly n pracce, he model parameers canno be calbraed drecly by observng raffc movemens. Therefore, a comparson mehod s presened o calbrae he model parameers approxmaely by comparng he resuls produced by dfferen mehods. albraons of Model Parameers a TW Inersecons A TW nersecons, he model parameers are esmaed by comparng he capaces obaned by he proposed models wh he observed capaces ( and he capaces compued by gap accepance heory ( a several ypcal observed nersecons. Ulmaely, he presened values of he model parameers can be gven by comprehensvely consderng he calbraon resuls (see Table. albraons of Model Parameers a AW and Unconrolled Inersecons mlar o he analycal mehod for TW nersecons, a AW and unconrolled nersecons, he model parameers are esmaed by comparng he capaces obaned by he proposed models wh he observed capaces ( and he capaces obaned by he relevan model from HM ( and he moorcade analyss mehod. The moorcade analyss mehod was recommended by Gao ( for esmang vehcular capaces of unconrolled nersecons on he bass of characerscs of vehcles alernaely crossng unconrolled nersecons n erms of moorcades. The presened values of he model parameers can be gven by comprehensvely consderng he calbraon resuls: Vehcular Movemen Bb (s a (s,,,..,,,.. 6,,.. Deermnaon of Model Parameers nce basc values of he model parameer Bb are gven for passenger cars, he nfluence of heavy vehcles, approach grade, and T-nersecons on he model parameer B s no consdered n he process of calbraon. Adusmens are made o accoun for hese mpac facors (. The model parameer B s compued separaely for each vehcular movemen as follows: B Bb + BH PH + BG G LT ( TABLE Presened Values of Model Parameers a TW Inersecons Vehcular Movemen Bb (s a (s,..,....,.6.,.. 6,.. OTE: Bb he basc average me of a vehcle crossng conflc areas for vehcular movemen.

8 6 Transporaon Research Record (alculaed [veh/h] (Observed [veh/h] LT TH RT (alculaed [veh/h] LT TH RT (Observed [veh/h] FIGURE 6 omparsons of observed capaces and capaces calculaed by proposed models a mnor sree TW nersecons ( capacy, LT lef urn, TH hrough, and RT rgh urn. FIGURE omparsons of observed capaces and capaces calculaed by he proposed models a unconrolled nersecons. BH adusmen facor for heavy vehcles (. for wo-lane srees and. for four-lane srees, P H proporon of heavy vehcles for vehcular movemen, BG adusmen facor for approach grade (. for rgh-urn movemens and. for lef-urn and hrough movemens, G percen grade dvded by, and LT adusmen facor for he nersecon geomery (. for lef-urn movemens a T-nersecons;. oherwse. EVALUATIO OF APAITY MODEL To check wheher he proposed models yeld realsc resuls, he calculaed capaces are compared wh he observed capaces a ypcal TW (Fgure 6 and unconrolled (Fgure nersecons. On average, here s a good correspondence beween he observed capaces and he calculaed capaces. Furhermore, he calculaed capaces of he proposed models are compared wh he cal- culaed capaces of boh gap accepance heory ( (Fgure and he moorcade analyss mehod ( (Fgure o assess he effecveness of he proposed models. nce convenonal mehods do no consder pedesrans and bcyclss, he comparsons are lmed o vehcular movemens. The resuls ndcae ha he calculaon mehods yeld smlar values. Fgures 6 and presen capaces of mnor sree movemens, whle Fgures and presen maor sree capaces. OLUIO Ths paper presens a seres of models for deermnng capaces of vehcular movemens a TW, AW, and unconrolled nersecons. The models exend he capables of exsng models by ncorporang pedesran and bcycle movemens. Ths aspec of operaon s especally mporan for urban nersecons wh mxed raffc movemens. The models for obanng he capaces of vehcular movemens have been derved by he conflc echnque mehod under mxed raffc condons. The model parameers have been calbraed for raffc condons n hna on he bass of he feld daa. (onflc echnque [veh/h] LT TH RT (Gap accepance heory [veh/h] FIGURE omparsons of capaces calculaed by proposed models and capaces obaned by gap accepance heory a TW nersecons. (onflc echnque [veh/h] LT TH RT (Moorcade analyss mehod [veh/h] FIGURE omparsons of capaces calculaed by proposed models and capaces obaned by moorcade analyss mehod a unconrolled nersecons.

9 L, Deng, Tan, and Hu The model evaluaons show ha he proposed models yelded realsc capacy esmaons of vehcular movemens, alhough more comprehensve daa for calbraon and valdaon are desrable. The research shows ha realsc capacy esmaons can be acheved f noncomplance wh raffc rules s regarded n he models. The model resuls ndcae ha he nfluence of pedesran and bcycle movemens on he capaces of vehcular movemens canno be gnored. In concluson, he proposed models provde valuable ools for deermnng capaces a unsgnalzed nersecons under mxed raffc condons, ypcally seen n developng counres lke hna. REFEREE. Harders, J. The apacy of Unsgnalzed Urban Inersecons. Forschung raßenbau und raßenverkehrsechnk, German Hef 6, 6.. egloch, W. apacy Evaluaon a Unsgnalzed Inersecons. rassenbau und rassenverkehrsechnk, Bundesmnser fuer Verkehr, Bonn, Germany, o... Grossmann, M. Updaed alculaon Mehod for Unsgnalzed Inersecons. Forschung rassenbau und rassenverkehrsechnk, Bundesmnser fuer Verkehr, Bonn, Germany,, o. 6.. Hghway apacy Manual. TRB, aonal Research ouncl, Washngon, D..,.. Brlon, W., and. Wu. apacy a Unsgnalzed Inersecons Derved by onflc Technque. In Transporaon Research Record: Journal of he Transporaon Research Board, o. 6, TRB, aonal Research ouncl, Washngon, D..,, pp.. 6. Brlon, W., and T. Mlner. apacy a Inersecons Whou Traffc gnals. In Transporaon Research Record: Journal of he Transpora- on Research Board, o., Transporaon Research Board of he aonal Academes, Washngon, D..,, pp... Heber, J. A udy of Four-Way op Inersecon apaces. In Hghway Research Record, HRB, aonal Research ouncl, Washngon, D.., 6.. Rchardson, A. J. A Delay Model for Mulway op-gn Inersecons. In Transporaon Research Record, TRB, aonal Research ouncl, Washngon, D..,.. pecal Repor : Hghway apacy Manual, nd ed. TRB, aonal Research ouncl, Washngon, D..,.. Kye, M. Proposed Draf ompuaonal Procedures, apacy and Level of ervce of Unsgnalzed Inersecons (HM. Unversy of Idaho, Moscow, 6.. Wu,. Deermnaon of apacy a All-Way op-onrolled Inersecons. In Transporaon Research Record: Journal of he Transporaon Research Board, o., TRB, aonal Research ouncl, Washngon, D..,, pp... Wu,. Transporaon Research rcular E-: apacy a All-Way op-onrolled and Frs-In-Frs-Ou Inersecons. TRB, aonal Research ouncl, Washngon, D..,.. Wu,. Toal apaces a All-Way op-onrolled Inersecons: Valdaon and omparson of Hghway apacy Manual Procedure and Addon-onflc-Flow Technque. In Transporaon Research Record: Journal of he Transporaon Research Board, o., Transporaon Research Board of he aonal Academes, Washngon, D..,.. Kye, M. apacy and Level of ervce a Unsgnalzed Inersecons. HRP Proec -6. TRB, aonal Research ouncl, Washngon, D.., 6.. Gao, H. The Analyss Mehods of apacy a Hghway Inersecons. PhD dsseraon. ouheas Unversy, anng, hna,. The Hghway apacy and Qualy of ervce ommee sponsored publcaon of hs paper.