Empirical Study of Parking Problem on University Campus

Transcription

1 JOURNAL OF TRANSPORTATION SYSTEMS ENGINEERING AND INFORMATION TECHNOLOGY Volume 7, Issue 2, Aprl 2007 Onlne Englsh edton of the Chnese language journal Cte ths artcle as: J Transpn Sys Eng & IT, 2007, 7(2), RESEARCH PAPER Emprcal Study of Parkng Problem on Unversty Campus SHANG Huayan, LIN Wenj, HUANG Hajun * School of Economcs and Management, Bejng Unversty of Aeronautcs and Astronautcs, Bejng , Chna Abstract: In recent years, more and more unversty employees tend to choose ther resdences n places outsde the campus. As a result of ths change, the number of prvate cars owned by them s ncreasng rapdly. In addton, the communcaton between unverstes and communtes has become much closer than before. Ths leads to a shortage of campus parkng capacty. Ths artcle has presented a case study of the campus parkng problem, takng the Bejng Unversty of Aeronautcs and Astronautcs as an example. The campus nflow and outflow of vehcles, the locaton and use of parkng lots as well as the drvers parkng behavor are surveyed and analyzed. The average parkng duraton and the use turnovers of parkng lots are computed from the survey data. Key Words: campus; parkng system; parkng lot; parkng behavor 1 Introducton The unversty campus provdes all staff and students a place for ther workng, studyng and even lvng. Parkng s one of the mportant topcs n urban transportaton plannng and traffc management. Ths s true too for the unversty campus. In recent years, Chna s hgher educaton has developed rapdly, whch has led to a dramatc ncrease of students educated on campuses and thus severe shortage of land used for teachng and researchng. For provdng students enough space for lvng and guaranteeng the land used for teachng and researchng, many unversty employees who orgnally lved on the campus are encouraged to move out. They have to buy prvate cars used for commutng between ther lvng places and the campus. Consequently the number of prvate cars owned by them has ncreased notably. In addton, the communcaton between unverstes and communtes s much closer than before because of the system reform currently occurrng n ths country. Therefore, how to formulate and manage the campus transportaton system, partcularly the parkng subsystem, has attracted much attenton n both academc and practcal crcles. Early n 1990, McIntyre made a survey n twenty-fve communty colleges n Calforna and recommended some measures for mprovng the campus parkng envronment. Carl and Davd (2001) appled mathematcal models to nvestgate the effects of varous campus parkng polces. In manland Chna, Leng and Yan (2003) examned the unversty campus systems for takng account of the specfc condtons. Song and Wang (2004) conducted several relevant surveys n Chnese unverstes. Overall, however, few systematc reports of the studes on campus parkng problems can be found n lterature. Ths artcle takes the campus of the Bejng Unversty of Aeronautcs and Astronautcs (BUAA) as an example, and ams to fnd the general features exstng n the campus parkng systems. Analyss has been made on the campus nflow and outflow of vehcles, locaton of parkng lots, and correspondng capacty, as well as the drvers parkng behavor. Moreover, the average parkng duraton of each vehcle and the use turnovers of some parkng areas have been computed. On the bass of these statstcal results, the problems have been explored and suggestons have been gven for mprovng the campus parkng system. It s expected that ths case study can beneft the solvng of smlar problems exstng n other unverstes. 2 Outlne of the survey method The BUAA campus, occupyng about one klometer square, looks lke a square. It can approxmately be dvded nto four areas accordng to ther functons, namely, the household zone, Receved date: *Correspondng author. E-mal: hajunhuang@buaa.edu.cn Foundaton tem: the Natonal Basc Research Program of Chna (2006CB705503) Copyrght 2007, Chna Assocaton for Scence and Technology. Electronc verson publshed by Elsever Lmted. All rghts reserved.

2 teachng zone, student dormtory zone and publc actvty zone. The teachng zone usually closes down on both vehcles and bcycles; the publc actvty and household zones bear the man responsblty for vehcle and bcycle parkng. All offce buldngs, refectores, shops, playgrounds, gymnasums, banks, post offces, afflated hosptal, kndergarten, prmary school and mddle school are located n the publc zone. There are 442 parkng lots totally wthn the publc zone. Although 663 parkng lots are avalable wthn the household zone and the external vehcles are allowed to park there, they stll choose to park n the publc zone. Ths s manly because the household zone s relatvely ndependent of other zones. Thus, the case study presented n ths artcle s only subject to the parkng problem wthn the publc zone. The north and southeast gates are the two channels for vehcles to enter or ext the campus. Therefore, surveyors are arranged to count the enterng and extng vehcles accordng to the n and out drectons at these two gates. For each vehcle, the entry and ext tmes are recorded together wth the last three numbers shown on ts lcense plate. Through comparng the lcense numbers of vehcles, all vehcles can be dentfed and ther parkng tme spans on the campus obtaned, that s, the ext tme mnus the entry tme. Surveyors then count all parkng lots on the campus and observe the occupancy rates of these lots durng dfferent tme perods by havng one walkng tour each 0.5 hour. The entre study horzon [O, T] = 7:00 19:00 s equally dscretzed nto T ntervals, and the length of each one s δ=5 mn, T δ = T. If a vehcle enters the campus at tme nterval t 1 and exts at tme nterval t 2, then ts tme span for parkng on the campus s Δ t = t2 t1 nterval. Assume that the summaton of the travel tme spent on the campus and the tme delay for searchng for a parkng lot s no more than 10 mn, the parkng behavor can be descrbed as follows: f Δ t = ( 0,1, 2), t follows that vehcles, (e.g., Taxes), stay on the campus for a very short tme duraton and these parkng behavors are gnored n ths case study. If Δ t > 2, t follows that vehcles need formal spaces for parkng on the campus, and the parkng tme equals to 5( Δ t 2) mn. Let f (k) be the flow enterng the campus durng nterval k and parkng n the lot. The cumulatve arrval at lot by nterval t (excludng t), U (t), s t U () t = f ( k), I k= 1 Where s the set of all surveyed parkng lots on the campus. The total arrval for parkng by nterval t s: I (1) U ( t) = U ( t), t ( 0,1,2, L, T ) (2) Note that these vehcles arrvng at lot before nterval (t l) and parkng for the duraton l( 1) wll leave the lot before nterval t. Thus, the cumulatve departure, V () t, by nterval t can be computed as follows: t 1 l k = 1 ( ) V() t = f( k), I, t 0,1,2, L, T (3) where V () t = 0 for t = (0,1,2). Then Vt () = Vt (), t ( 0,1,2, L, T) (4) I The accumulatve number of vehcles parkng at lot durng nterval t equals U (t) mnus V (t), that s, ( ) D () t = U () t V (), t I, t 0,1,2, L, T (5) And the accumulatve number of vehcles parkng at all lots durng nterval t s (6) D() t = D (), t t 0,1,2, L, T I ( ) Where D(t) s called the parkng demand durng tme nterval t. 3 Statstcal results and analyses On average, there are 8,267 vehcles enterng and extng the BUAA campus each day, among whch 2,017 and 2,045 ones enter and depart from the north gate and 2,081 and 2,124 ones enter and depart from the southeast gate, respectvely. Fg. 1 shows the number of vehcles enterng and extng the campus for every fve mnutes wthn a workng day. It can be seen that there are two peaks correspondng to the perods 7:00 8:30 and 17:00 18:30, respectvely. Number of vehcles per nterval Inflow Outflow Tme Fg. 1 The number of vehcles enterng and extng the campus for every fve mnutes In the publc zone, there are manly sx lots for parkng, located around Syuan Buldng (denoted as A n ths artcle), Twelfth to Nneteenth Buldng (B), Zhxng Buldng (C), Offce Buldng (D), Gymnasums (E), and Yougou Mall (F), respectvely. The realzed parkng demands assocated wth these lots for every fve mnutes are depcted n Fg. 2. It can be seen that the realzed demands n all lots, except D and E,

3 fluctuate slghtly and are less than 50. D s the most mportant lot for parkng on ths campus wth regard to both the demand level and the physcal confguraton. Durng the perods 8:00 12:00 and 14:00 17:30, more than 110 vehcles park and constantly stay there. Durng 12:00 14:00, some people drve away to have lunch. Number of vehcles Tme Fg. 2 Realzed parkng demands n sx lots The total demand for parkng on the BUAA campus s not the smple summaton of the demands of the sx parkng lots descrbed above. Those vehcles that park on the streets and n other unmportant stes should also be consdered. Wth ncluson of these vehcles, Fg. 3 shows the total parkng demands of the campus for each tme nterval. From ths fgure, t can be seen that durng the perod 7:00 8:00, the parkng demands ncrease rapdly (46.7 parkng berths per tme nterval) and ascend to a maxmum at 11:00, and then declne durng the whole afternoon. After 8:00, the ascendng speed of the demand gets down, 15.7 parkng berths per tme nterval. It further decreases after 9:00, only 5.7 parkng berths per tme nterval. Durng the whole afternoon, the parkng demands decrease constantly, but wth dfferent speeds durng dfferent perods, three parkng berths per tme nterval before 14:30, 11.2 from 14:30 to 17:00 and then Number of vehcles Tme Parkng demand Parkng supply Fg. 3 Changes of total parkng demands on the campus durng dfferent tme perods Compared wth the formal supply for parkng provded n the publc zone, the demand starts to exceed the supply from 7:50, as shown n Fg. 3. Ths stuaton lasts for about nne hours tll 17:30. There s an excess of 800 vehcles durng the perod 9:00 14:30 on an average, and even 900 vehcles durng 11:00 12:00. Obvously, the present parkng capacty s not enough to meet the demands durng the on-duty tme perod of a day. Table 1 presents the demands wth dfferent tme spans for parkng. The average parkng tme span on the BUAA campus s 268 mn. More than half of the parkng vehcles, 54.5 % of the total, stay on the campus for less than three hours. It s stated n detal that 13.6 % stay for less than 10 mn, 19.4 % for 10 mn to one hour, and 12.1 % for 1 2 h. Bascally, the owners of these vehcles stayng for less than two hours are not the employees of the BUAA or the students. Actually, 45.1 % of the vehcles parkng on the campus are not owned by the BUAA employees or students. Thus, how well these vehcles can be managed s an mportant problem to be resolved for ths unversty. Let l be the length of tme duraton for parkng. Fg. 4 shows the flow pattern demonstrated by a number of vehcles enterng the campus and stayng there wth dfferent tme spans. It s clear that after the tme t=19:00 l, no vehcles enter the campus and park for duraton l. Before the tme t=19:00 l, however, there always exst some vehcles enterng the campus and parkng for duraton l, although the enterng number at dfferent tmes evdently dffer. Vehcles parkng for short duraton enter the campus stochastcally (the drvers are Taxes). Vehcles parkng for one hour enter the campus manly durng 7:00 9:00 (the drvers come to ths unversty for busness). Vehcles parkng for two hours enter the campus manly durng perods 7:00 9:40, 13:30 14:30 and 16:00 17:30 (the drvers enter the campus for havng college courses or semnars). Vehcles parkng for three hours enter the campus manly durng 7:00 8:00 (for courses arranged durng nght). And vehcles parkng for four, fve and sx hours enter the campus manly durng the tme perods 7:00 8:00 and 14:00 15:00, the perods 7:00 8:00 and 13:00 14:30, and the perod 7:00 9:00, respectvely. To summarze, the longer the duraton a vehcle parks for, the earler t enters the campus. As defned n Secton 2, D (1) s the total amount of vehcles arrvng at parkng lot n tme nterval t=1. For nterval 1< t 144, ΔD ( t) = D ( t) D ( t 1) > 0 mples that there are Δ D () t vehcles parkng at lot durng nterval t ; otherwse, ΔD ( t) < 0 mples Δ D () t vehcles leave the lot durng nterval t. ΔD ( t) = 0 states that there are no vehcles enterng or extng the lot durng nterval t ; thus, the number of parkng vehcles at remans unchanged from nterval t 1 to t. Thus, the use turnovers of parkng lots can be estmated from the survey data D () t as follows:

4 144 Δ D() t + D(1) =, Δ D( t) = D( t) D( t 1), I t= 2 α 2w (7) Where w represents the number of berths provded at lot and α s the use turnover of lot. Table 1 Parkng demands wth dfferent tme spans Tme span for parkng Demand Percentage Accumulatve percentage Short duraton Δt =(0,1,2) For 1 hour 3 Δt < For 2 hours 14 Δt < For 3 hours 26 Δt < For 4 hours 38 Δt < For 5 hours 50 Δt < For 6 hours 62 Δt < For 7 hours 74 Δt < For 8 hours 86 Δt < For 9 hours 98 Δt < For 10 hours 110 Δt < For 11 hours 122 Δt < For 12 hours 134 Δt < Note: Δt denotes the amount of tme ntervals for parkng on the campus, one of whch s 5 mn; one hour equals 12 ntervals; the parkng tme span s l= Δt 2. Short duraton Number of vehcles Tme Fg. 4 Number of vehcles enterng the campus and stayng wth dfferent tme spans Table 2 gves the use turnovers of sx parkng lots. It s found that these turnovers are not so hgh as expected. Ths s manly because a lot of vehcles, 45.5 % of the total, park and stay on the campus for over four hours. These vehcles occupy the parkng berths durng peak perods and leave the campus after work. At that tme, the parkng lots cannot attract new comers any more. The lots B, C, and D are occuped by some fxed demands durng the day tme. The turnover of lots D and F s relatvely hgher than that of other lots. On the one hand, the fact that the demand exceeds supply requres hgher turnovers n usng the parkng lots; on the other hand, too many vehcles stay on the campus for over

5 four hours, whch block the enhancement of turnovers. Ths s a dstngushng feature of the campus parkng systems, dfferng from the systems n other communtes. Parkng lots Table 2 The use turnovers of sx parkng lots Number of berths avalable Turnover A B C D E F The survey results also show that these vehcles stayng on the campus for a long tme commonly park on fxed berths, and those stayng for a short tme change postons for parkng frequently and even park on streets when the drvers cannot fnd berths for convenent parkng. For example, durng peak perods, up to 15 and 11 vehcles choose to park near the afflated prmary school and tenns gym, respectvely. In the publc zone, some drvers park ther cars everywhere at wll. In other words, on-street parkng has become a method to solve the shortage of parkng supply, whch s certanly not expected by the unversty manager. There are fve man streets on the BUAA campus, namely, the campus south, the campus north, the campus west, the campus east and the campus mddle streets, respectvely. Vehcles are not allowed to enter the campus east and mddle streets durng the perods 7:30 8:30, 11:30 12:30, 13:30 14:30 and 17:30 18:30 to allow a safe flow of pedestrans and bcycles. However, on-street parkng can stll be observed everywhere n the publc zone because of the shortage and nconvenence of parkng supply, whch often nduces traffc jams and even accdents. For example, one secton of the campus east street s located near the afflated prmary school. Ths two-way street has a wdth of 8.5 meters, but s often occuped by two rows of cars parked on both sdes; thus, only a narrow space of 3.5 meters s avalable for walkng and vehcle movement. Every day, ths secton s very crowed when pupls go to or leave school. Moreover, one row of vehcles and one row of bcycles park on both sdes of a road between the unversty admnstraton buldng and the Scence buldng. Ths road connects to the teachng zone of the unversty. It naturally becomes congested and unsafe when many students ext from the teachng zone after classes. A smlar phenomenon s observed on the campus west street. Therefore, ths s an appeal for a new scheme for regulatng the BUAA campus parkng, and t should be materalzed as soon as possble. 4 Conclusons In summary, the BUAA campus parkng system has the followng characterstcs and problems: () Most vehcles park n the zone for publc actvtes. The number s large n the daytme and small n the nghttme; large durng on-duty tme and small durng off-duty tme. The vehcles parkng for more than four hours consttute the majorty of vehcles parkng on ths campus. () Ths campus clearly lacks parkng berths. Meanwhle, the use turnovers of the current parkng lots are low. () The current parkng lots utlze the ground spaces around buldngs. Recently, a specally desgned underground parkng lot under the New Man Buldng s ready to come nto use. It s expected to solve the parkng problem n the southeast area of the campus. (v) The on-street parkng has caused a seres of problems, ncludng traffc jam, and thus s dangerous for pedestrans. (v) A lot of vehcles, not owned by the unversty employees, run through the campus everyday, whch further burdens the campus traffc. (v) Parkng tolls only nfluence the vehcles wthout entry permts, and the unversty employees put ther vehcles on the campus for a long tme wthout any restrants. As a result, the use turnovers of parkng lots are very low, less than two on an average. It s beleved that the phenomena and problems found on the BUAA campus commonly exst n other Chnese unverstes, and thus t s expected that ths artcle can beneft the studes of other campus parkng systems. The BUAA campus has been selected as one of the places for the actvtes of the Bejng 2008 Olympc Games. The campus traffc s a hot topc dscussed by people. It s hoped that ths artcle can further stmulate the dscusson. References [1] McIntyre C. Calforna Communty Colleges Parkng Survey, [2] Carl V P, Davd S S. Basc Methods of Polcy Analyss and Plannng, Bejng, Chna: Huaxa Publshng, [3] Leng J, Yan K F. Proposal for mprovng the campus parkng of Tongj Unversty. Traffc and Transportaton, 2003, 5: [4] Song H F, Wang G H. Survey on unversty campus traffc problem and suggestons. Zhejang Statstcs, 2004, 4: [5] Tong C O, Wong S C, Leung B S. Estmaton of parkng accumulaton profles from survey data. Transportaton, 2004, 31: [6] Huang H J, L Z C, Lam W H K, et al. A tme-dependent actvty and travel choce model wth multple parkng optons. In: Transportaton and Traffc Theory, Mahmassan H S (Ed.), Oxford: Elsever, 2005:

6 [7] Lam W H K, L Z C, Huang H J, et al. Modelng tme-dependent travel choce problems n road networks wth multple user classes and multple parkng facltes. Transportaton Research Part B, 2006, 40(5): [8] Hensher D A, Kng J. Parkng demand and responsveness to supply, prcng and locaton n the Sydney central busness dstrct. Transportaton Research Part A, 2001, 35(3): [9] Guo N. Quanttatve analyses about the parkng problem n resdence area. Ph.D. dssertaton, Zhejang Unversty, Chna, [10] Guo T, Yang T, Wang R P, et al. A new decson-makng method for plannng the urban parkng facltes. Journal of Transportaton Systems Engneerng and Informaton Technology, 2006, 6(4):

7 ID Ttle Pages Emprcal Study of Parkng Problem on Unversty Campus 6