Research on the Design of Underground Complex of Subway Parking Lot

Liu Dianlei

(Shanghai New Construction Architectural Design Co．,LTD,Shanghai 200065)

Abstract:Rail transit is an important part of public transportation in China.Generally,only one parking lot will be set up for the subway line due to site reasons,but the construction of parking lot will still occupy a large area of land,which is inconsistent with the policy of saving land in the city.The oversize parking lot hinders the development of rail transit.In order to solve the problem of parking lot,the subway parking lot is set underground,and the complex containing the underground subway parking lot is set.However,there are many problems to be solved in the underground complex of subway parking lots.This paper will study the design of underground subway parking complex,hoping to provide help for the future development and construction of underground subway parkingcomplex.

Keywords:underground subway parkinglot;underground complex;design study

With the continuous improvement of China"s economic strength and the acceleration of urbanization across China,more and more people are crowding into big cities.How to make good use of urban land resources and develop public transportation is a very important issue.Rapid rail transit is the major public transportation in major cities in China.The parking lot set on the subway line in China occupies too large area and fails to achieve the purpose of saving urban land,which is the obstacle to the development of rail transit.In the future,setting parking lots underground will achieve the purpose of rational use of land.However,there are many problems in the complex design of subway parking lots.This paper will propose design treatment methods for this complex and provide references for the subsequent underground complex design of subway parkinglots.

I.Present Difficulties in the Design of Underground Complex of Subway Parking Lot

(i)Diversity and Complexity exity

The development of subway parking underground complex can make the urban underground land be used more rationally and provide more high-value land for the ground.Therefore,in the design and construction,it is necessary to ensure that the normal work of the subway is not affected,so that the above-ground land resources can be used by the public as much as possible,and the high-value land resources can be obtained in the city with rapid development.When designing underground subway car park,these aspects should be paid attention:the setting of civil air defense is necessary,flexible processing can be made in many sudden events,at the same time in order to let the crowd evacuate quickly from the parking lot,a set of independent evacuation system should be set up,parking lot exits and entrances should be broad clear,entrances and exits only have one-way road,the phenomenon such as borrow the way cannot appear.

The establishment of underground business will attract a large number of people and increase the landscape above the ground,thus attracting more customers.Light and air mobility should be taken into consideration in underground businesses designing,with good lightingand smooth ventilation.

The construction of underground parking lots will provide a large number of parking spaces,which can alleviate the phenomenon of random parking on the square.At the same time,because it is convenient for people to take the subway,people will choose the subway for more ways of travel,which is more low-carbon and environmentally friendly.In the functional design of the underground parking lot,such as entrance and exit setting,exhaust air shaft,etc.,these are necessary settings,but they cover a large area and are located in the key parts of the underground,which will greatly affect the layout of other functions.

(ii) Contradictions in the Underground round Synthesis hesis

The underground complex of subway parking lot has diversified functions,each of which is relatively independent but closely related.For example,subway and business are two independent industries with obvious distinctions,but they need to be connected in the complex,so as to ensure the connection between customers" shopping and subway.There are three main connections between subway and business.

1.Traffic and shopping.In order to make it convenient for people to take the subway,the underground parking lot should be connected to the subway station.In order to enable customers to get on the vehicles as soon as possible after shopping,the connection between the commercial parking lot and thesubway station should be strengthened.

2. Public and private. In the whole comprehensive system,the public and private areas should be distinguished,and the character of underground business,subway station,underground garage,underground parking lot and other places should bedistinguished.

3.The design of underground space conflicts with the ground.In order to facilitate the future construction and road design of the ground,it is better to make the underground part of the ground less and more concentrated.In order to facilitate the implementation of various functions of the underground,at the same time,it is also hoped that the construction of the ground can be decentralized and the amount of construction reduced,which results in the contradiction between the underground space design and the ground[1].Some of the necessary underground design will be out of the ground,such as the wind shaft,stairs and elevators,etc.,have these out of the ground of the building not been managed well when the ground is in preparation for the construction,it will cause the ground design messy phenomenon.

II.Design and Analysis of Underground Synthesis

(i)Position Determination ation

In the design of underground complex,it is necessary to refer to the map in time,observe the surrounding building design and location of the target site,and check the design of underground pipeline.It is necessary to integrate multiple maps and consider possible problems in the design,make corrections in time and prevent the occurrence of events,so as to work out the location of underground complex.

(ii)Function Arrangement ement

Underground subway parking lots,underground social parking garages,underground businesses and above-ground public green Spaces are all functionsof underground complexes.

Business format setting.According to business plan in design project,the underground complex is subdivided in detail,in order to maximum use the limited space.

(iii)Platform Setting tting

In order to improve the whole safety coefficient of underground complex,let the masses evacuate the scene in the fastest speed at the time of the accident,the station platform,the station hall,and the entrances and exits shall not be allowed to set up business place.If the platform and station hall want to set some window,also the subway operation,service equipment can be allowed,or setting the project function too much will affect the speed of passengers"evacuation.

(iv)Fire Control Analysis lysis

China has clear specifications for subway design. In the development of underground commerce,fire prevention work should be divided into different zones.Underground commerce and other areas should be clearly divided,and the fire prevention work should be in line with the relevant provisions in the national standard Building Design Fire Code[2].

In the fire protection design of underground commercial and underground social parking garage,the two should be divided into fire prevention zones.Each zone should meet its own requirements,and each zone should have its own unique evacuation method,so that the evacuation work can be realized in the design of each zone.

The design of underground subway parking lot has not developed rapidly in China,because it has less experience in implementation and is more difficult to design.The relationship from the ground to the underground interface is complex,and there are still a lot of problems in the planning and design.There are no complete specifications for the design of underground subway parkinglot in China.

III.Underground Space Synthesis

In order to make the layout of the underground complex clear,unified and reasonable,the functions are divided.In order to facilitate people to reach the business district,the business district is arranged on the first floor underground,and part of the houses are used as subway parking lot.These two parts should be separated into two systems.The second floor underground is set up as garage and underground subway parking lot.In the evacuation system,the two should be separated and not mixed intoone.

According to the characteristics and design requirements of the long dike,appropriate places should be used as the evacuation space,and lighting should be paid attention to to introduce light into the area[3].

1. Two sides design scheme. Make development of sunken square on both sides,which can not only allows for evacuation but also allows for the introduction of sunlight.The advantage of this design is that it can move the landscape on both sides to the sunken square,so as to improve the opening scene of the business,give up the buildings or facilities on the ground,and give the ground more development space.It can also improve the ability to attract customers by greatly increasing the ground landscape.The disadvantage is that the commercial scope provided by the sunken square is limited.The sunken square occupies a large area of underground space,which reduces the utilization rate of the overall space.The retaining walls on both sides of the sunken square are high and thick,and the wall area is large,which increases the capital invested on the wall.

2.Intermediate design scheme.Digging around the ground floor allows the subway to form a large open space.This design enhances the connectivity between the commercial and the underground open space,making it easier to divide the functions of the complex.The advantage of the middle is:sinking space has good dimension,there is no need to design additional cantilever enclosure wall,which reduces the problem of large amount of materials when building the wall.The disadvantage is:The combination of surface and underground technologies will be more difficult,and the streetsidelandscapemay beaffected by thedesign.

3.One side design scheme.This scheme makes the functional divisions of the complex visible,with each one concentrated on one side.The subway function will be placed on one side,and this side is only for subway function,underground commerce and underground garage will be placed on the other side,while the selection of sunken plaza is designed in the middle of commerce,which can improve the effect of evacuation and bring air and light into the underground.The advantage of this design is that zoning is more obvious and relatively independent,which makes subway underground parking lot a system and underground commerce and underground garage another system.The design of shopping malls on the distribution can be less constrained and make the design more flexible.Disadvantages:the underground subway parking lot is obviously separated from the commercial area,which reduces the connection between the two.The side plan will disturb the flow of shopping people,and the commercial formwill also be affected.

According to the different conditions and requirements of the site,the most suitable plan should be selected and stratified reasonably.Meanwhile,lighting and ventilation should be taken into consideration to make the complex as perfect as possible and adapt to the characteristics of local development[4].

IV.Fire Protection Design

(i)Fire Division ision

Automatic fire extinguishing system settings should be different due to the difference of control region.Things in underground department store are valuable and flammable,so fire partition area should be a bit bigger,generally within 2000m.In places such as restaurants,fitness room and KTV is not easy to spread,fire zoning control area can be appropriately smaller,within 1000m.When design the garage fire partition,because of the large area,and the fire is easy to spread,the value loss is extremely large,so the area should be controled within 4000m.

(ii)Safe Evacuation ation

Special attention should be paid to the design of commercial safety evacuation,a pedestrian exit with direct access to the ground and sunken plazas should be provided in each fire protection zone,or two pedestrian exits with different sunken squares should be provided to let the evacuation speed of the crowd increase.For the orderly and rapid evacuation of large space interior,the distance of each exit should be 37.5m.In the design of each fire prevention zone of the equipment room,the number of exits should be increased,at least the exits leading to the ground or the sunken square should be set[5].Firewall and class A fire door are selected to separate each fire division.The evacuation door between the safety exits should not be set too far away from the best safety exit,which should be within 50m;The fire prevention area of the garage shall be set within a 60m radius of the front room of the stairwell.

V.Conclusion

Subway parking is an indispensable part of rail transit,but because of the increasingly tight land resources in the city,it is an inevitable development trend that subway parking becomes underground subway parking.At the same time,the underground complex is also developing rapidly,and the underground complex, such as underground business and underground parking lot, are constantly improving.If the underground complex of subway parking lot is popularized to all cities in China,then the land resources in China will be utilized more fully.However,the design of underground complex of subway parking lot is not perfect and is not popularize in China,which requires that the design of underground complex of subway parking lot in the future should take the actual situation in China and various factors around the city into account,so that the design of underground complex of subway parking lot can be widely applied to create more economic benefits.This paper discusses the design of underground complex of subway parking lot,and simply analyzes the location problems and methods existing in the complex,hoping to provide help for the design of underground complex of subway parking lot in the future.