Keywords

1 Introduction

The International Horticultural Expo, latest issue held in Chengdu in 2024, is the international highest level professional exhibition of landscape and horticulture, which can promote the exchange and development of economy, culture, science and technology around the world. The 2024 Chengdu International Horticultural Expo, with the theme of “Park City, Beautiful Habitat”, will be held from April 26th to October 28th, lasted for 184 days, is a continuous large-scale exhibition activity.

According to the previous International Horticultural Expo in China, the exhibition period will attract a large amount of visitors, which generated high intensity of transportation demand, will pose serious challenges to the organization and management of exhibition transportation [1, 2]. Previous studies on the transportation of continuous large-scale exhibition mainly focus on the analysis of visitor characteristics or traffic organization experience or daily visitor volume forecast [2,3,4]. Wang and Wan (2015) summarize transportation organization experience of Qingdao International Horticultural Exposition, which indicate that the overly dispersed layout of parking lots will bring significant inconvenience in terms of use and management [5]. Based on the basic parking data of the 2019 Beijing International Horticultural Exposition, Liu et al. (2022) analysis the parking characteristics, including the daily parking distribution characteristics, the average parking time on weekends and holidays, and the distribution of car entry and exit times, propose the parking supply and organizational control countermeasures, including advance booking ticket, graded response, remote information induction and near end traffic control, provide certain reference for the car parking demand prediction, parking facilities supply planning [6]. Karri Sowmya and Meera M. Dhabu show that the parking charge can efficiently manage parking occupancy during peak and off-peak hours [7]. Selcuk D. et al. using a GIS-based fuzzy analytical hierarchy process (AHP) approach analyze the problem of parking lot site selection in mega cities based on the three major standards of land, finance, and transportation, and indicate that transportation had the greatest weight while finance had the least weight [8].

Parking lots are an important infrastructure for exhibition activities. By properly solving the parking problem, the exhibition services, resources and facilities would be Effective fully utilized, which will maximize the benefits of the exhibition. However, there is a serious shortage of research on exhibition parking lot planning before the exhibition. Therefore, this article will focus on the research of parking lot planning and site selection schemes, which will be the foundation for improving the driving experience and enhancing the comprehensive evaluation of the Expo and provide guidance and basis for the construction of parking lots.

2 Parking Demand Analysis

2.1 Location and General Layout of the Expo

The main venue of the World Horticultural Exposition is located in the core area of Airport New City in the Eastern New District of Chengdu. Holding the Expo will drive the improvement of the urban infrastructure, aggregate a great number of the population, and improve the urban space morphology. The Expo covers an area of 242 hectares, surrounded by 4 main urban roads, and has five entrances and exits (as shown in Fig. 1). The NO. 1 and NO. 2 Entrance/Exit are the main entrances and exits of the Expo, mainly used to serve tourists, while other entrances and exits are used as functional Entrance/Exit to ensure conference affairs, or as backup entrances and exits which are only activated in emergency situations.

Fig. 1.
figure 1

The Entrance/Exit Layout of 2024 Chengdu World Horticultural Exposition

Full size image

2.2 Tourist Number Forecast

Based on the effective tourist area of the Expo, the maximum daily tourist capacity can be calculated, which is defined as:

$$ P_{daily} = \frac{{A_{valid} }}{{A_{per - capita} }} \times \frac{{T_{valid} }}{{T_{per - capita} }} $$
(1)

The \({P}_{daily}\) denote the maximum daily tourist capacity, the \({A}_{valid}\) denote the effective tourist area, the \({A}_{per-capita}\) denote the index of per capita tourist area, the \({T}_{valid}\) denote the daily effective opening hours of the Expo, and \({T}_{per-capita}\) denote the Average travel time of per capita tourist. The effective tourist area of the Expo includes exhibition gardens, roads, and squares.

Table 1. The calculation parameters of maximum daily tourist capacity.
Full size table

Using the corresponding parameters listed in Table 1, the maximum daily tourist capacity is calculated as 112.5 thousand people per-day. Considering the comfort of tourists, taking 86% of the calculated maximum daily tourist volume as the final maximum daily tourist volume, the final determined value is 96 thousand people per-day, which will be the tourists of extreme peak days.

By analogy with the experience of other city expo events in China (as shown in Table 2), it is predicted that the total number of tourists during the 2024 Chengdu Expo period will be approximately 5.5 million, with approximately 29 thousand tourists on weekdays, 49 thousand tourists on weekends, and approximately 97 thousand tourists on extreme peak days. The extreme peak days mainly refer to the long holidays during the 2024 Chengdu World Horticultural Exposition period, including May Day and National Day holidays.

Table 2. Analysis of total tourists on different days.
Full size table

2.3 Travel Model Split

As shown in Fig. 2, the 2024 Chengdu World Horticultural Exposition Park is relatively far from the surrounding major core cities, and is located in the Eastern New Area, which is also an urban new area under construction and has not yet formed scale. According to location relationship and urban development situation, tourists mainly come from nearby major cities, especially Chengdu with an estimated proportion of over 70%. Therefore, private car travel, as a convenient, comfortable, free and the suitable travel mode for long-distance, will be one of the main travel modes during the Expo.

Fig. 2.
figure 2

Major Cities Around the 2024 Chengdu World Horticultural Exposition

Full size image

As shown in Fig. 3, the Metro Line 18 has been built near the Expo, and the nearest metro station, Sancha station, is approximately 1.7 km away from the Expo in a straight line. The Metro Line 19 is planned to be put into operation by the end of 2023. During the operation of the Expo, the Expo can be connected to Tianfu International Airport, Shuangliu International Airport, and the city center of Chengdu through taking metro and then transferring to bus. Therefore, metro travel will be another major travel mode during the Expo.

Fig. 3.
figure 3

The Subway Resources for 2024 Chengdu World Horticultural Exposition

Full size image

Based on the above analysis, during the exhibition period, the proportion of travel modes is mainly composed of private cars (40%) and metro transit (35%), supplemented by tourism buses (12%) and dedicated bus (7%) (as shown in Fig. 4).

Fig. 4.
figure 4

The Travel Mode Split of 2024 Chengdu World Horticultural Exposition

Full size image

2.4 Parking Demand

Based on the tourist flow and travel mode split during the exhibition period, the total number of parking spaces demand under different dates, such as on weekdays, weekends, or extreme peak days, can be calculated using the following formula.

$$ Ps_{num} = P_{daily} \times Td_{pro} \times Veh_{cap} \div Tu_{rate} $$
(2)

The \(Ps_{num}\) denote the total number of parking spaces, the \(P_{daily}\) denote the maximum daily tourist capacity, the \({Td}_{pro}\) denote the proportion of travel modes, the \({Veh}_{cap}\) denote the average number of passengers per vehicle, the \(Tu_{rate}\) denote the daily turnover rate of parking spaces. There are three travel modes requiring parking spaces, including private car, tourist bus, dedicated bus.

Table 3. Calculation of parking spaces for 2024 Chengdu World Horticultural Exposition.
Full size table

From Table 3, we may conclude that there is actually a big difference of parking spaces between different days. Taking private car parking spaces as an example, the demand for parking spaces on weekdays is 4640, and on weekends it increases to 7840, while on extreme peak days it increases to 15520. Therefore, at the planning level, we need to differently and precisely provide parking spaces according to different operating conditions.

3 Parking Lots Site Selection

3.1 Parking Site Selection Principles

During the 2024 Chengdu World Horticultural Exposition of 186 days, there are totally 112 weekdays, 60 weekend days, and 14 extreme peak days. Therefore, the normalized parking spaces demand is mainly for weekdays and weekends. The parking lot site selection process is detailed in Fig. 5. Based on different operating exposition days, we propose three overall principles for selecting parking lot sizes, respectively including rigid supply workdays and weekends, flexible supply extreme peaks, time-sharing response and operations. Rigid supply parking spaces refer to fixed parking spaces located near the Entrance/Exit of the Expo Park, which can supply the parking demand of tourists on weekdays and weekends in a normalized and convenient manner. Flexible supply parking spaces refer to fully utilize the parking spaces of surrounding buildings of the Expo Park and fully excavate parking spaces of surrounding roads, in order to meet the parking demand of the not many extreme peak days. Due to the uneven daily tourist flow and fluctuating parking demand during the exhibition period, in order to reduce the operating costs and burden of parking lots, time-sharing response and operations refer that priority is given to using nearby parking lots on weekdays, weekends, and small and long holidays, while remote parking lots are used during extreme peak hours.

Fig. 5.
figure 5

Parking site selection general processes

Full size image

3.2 Parking Site Selection Land

There will be a large demand for the use of parking lots during the exhibition period, however, after the exhibition period the parking demand generated by the Expo Park will sharply decrease. Therefore, the parking lots for the Expo should be divided into two types: temporary parking lots during the exhibition period and permanent parking lots after the exhibition. When planning the layout of the parking lot, the actual situation of land use and the type of parking lot should be comprehensively considered to achieve a combination of permanent and temporary using function.

The permanent parking space should be combined with the comprehensive layout planning of the park, and should be as close as possible to the entrance and exit, and use the internal land of the park to facilitate the parking needs of tourists after the exhibition period. Temporary parking lots should avoid permanent basic farmland, which shouldn’t change its use under any circumstances. Therefore, temporary parking lots outside the park should be selected for urban construction land that has not yet been planned, and after the exhibition, the nature of the land should be restored according to the plan and priority should be given to construction.

3.3 Parking Lot Site Selection

According to the principles of selecting parking lots for the Expo and the surrounding land use, a total of 7 parking lots have been arranged, which will set a total of 9027 parking spaces (as shown in Table 4). The specific distribution of the parking lots are shown in Fig. 6. Among them, parking lots P1 to P5 are private car parking lots, while parking lots P6 and P7 are bus parking lots.

Fig. 6.
figure 6

Parking lot site selection layout of 2024 Chengdu World Horticultural Exposition

Full size image
Table 4. Basic information of the parking lots for 2024 Chengdu World Horticultural Exposition.
Full size table

The parking lot P6 is an exclusive parking lot for tourist buses and dedicated buses, with a quantity that can meet the parking demand of any period. To avoid interweaving with the traffic organization of private car tourists, tourist buses and dedicated buses first arrive at the No. 2 Entrance/Exit of the Expo Park to put down tourists, and then park at the P6 parking lot. According to the needs of tourists, tourist buses and dedicated buses can pick up tourists at the No. 1 Entrance/Exit or No. 2 Entrance/Exit to leave the Expo Park. P7 is a VIP exclusive bus parking lot that can only be used when needed.

The parking lots P1 and P2 are nearby the main Entrance/Exit, which are the main parking lots during the exhibition period. On normal working days, opening up the use of parking lots P1 and P2 can meet the parking demand of private cars. When on weekends, parking lot P3 will be activated to meet the increasing demand for private car parking. Parking lots P4 and P5 are located inside the park and serve as exclusive parking spaces for staff during the exhibition period, and will be retained as permanent parking spaces after the exhibition.

The surrounding buildings and the surrounding roads can be reasonably used to set about 7500 parking spaces, and reasonable traffic organization measures should be taken out to meet the parking demand during extreme peak days. The urban roads around the park are all urban trunk roads, with no less than 6 lanes in both directions, providing a basic guarantee for the traffic organization during the Expo period. In the future, special design will be carried out for traffic organization based on the functional layout of the park and the layout of parking lot location.

Due to the temporary parking lots outside the Expo Park only used for the exhibition period of 186 days, the construction of the temporary parking lots should minimize investment as much as possible. Therefore, the temporary parking lots outside the park should be arranged in accordance with the terrain and topography as much as possible to reduce engineering earthwork. And some high-quality natural native trees within the site can be retained according to the actual situation, forming a natural landscape.

4 Conclusion

This article analyzes the number of tourists at different days during the 2024 Chengdu International Horticultural Exposition, and combines the public transportation resources around the Expo Park to predict the proportion of travel modes. Based on this, the parking space demand of private cars, tourist buses and dedicated buses on weekdays, weekends and extreme peak days are detailed analyzed and then calculated out. According to the distribution of entrances and exits of the Expo Park and the surrounding land use, a total of 7 parking lots, including a total of 8457 private parking spaces and 570 tourist/dedicated buses, are planned and arranged to meet the rigid parking demand on weekdays and weekends. The surrounding buildings and the surrounding roads would be reasonably used to set about 7500 flexible parking spaces to meet the parking demand during extreme peak days. By planning and laying out the parking lots for the Expo in advance, it will help solidify the land use for parking facilities and carry out land requisition and consolidation in advance. Setting the parking lot location in advance will be an important prerequisite for the special design of traffic organization in the later stage of the 2024 Chengdu World Horticultural Exposition and will greatly facilitate the smooth development of traffic organization in the later stage. The research has not integrated into the construction stage and is relatively not in-depth enough, further research can be conducted based on the actual tourist flow and parking lot operation of the Expo for in-depth analysis.