COMPARATIVE EVALUATION OF ALTERNATIVE METHODS

FOR THE CONSTRUCTION OF UNDERGROUND CAR PARKS

M.C. PAPPACivil Engineer, Msc, Greece

A.G. BenardosPhd, Lab. of Mining & Environmental

Technology-NTUA, Greece

Importance of parking spaces – Underground car parks

The problem.Lack of parking spaces in the large urbancenters.

The consequences.Traffic jams and long delays.

Environmental pollution.

The solution. Underground parking areas.

Advantages

Preservation of valuable surface space.

High availability.

Environmental protection.

High construction and service cost.

Importance of parking spaces – Underground car parks

Disadvantages

Motives for the construction of underground parking stations

Subsidy 4.108 € / per parking place

Conditions

Creation of at least 40 parking places stations of public use.

Demonstration of the necessity of the underground parking construction.

Alternative Methods for the Construction of Underground Car Parks

Cut and Cover Room and Pillar

Cut and Cover Method

Field of Application .

Loose soil of top layers.

Hard soil (in exceptional cases).

General outline

Support of the cutting perimetric walls.

Steel strands.

Reinforced concrete.

Tensile anchors.

Cases examined

Parking Station Surface (m2) Volume (m3) FloorsCapacity

(cars)

Paidon Hospital Square 17.433 54.764 5 576

Rizari Street 18.997 56.339 4 664

Kaniggos Square 15.401 49.283 4 491

Cut and Cover Method

Cut and Cover Method

Kaniggos Square

Cost Analysis – Key issues

0

5

10

15

20

25

30

35

40

Des

ign Studies

Sup

port

Exc

avation

Con

crete

Water

proo

fing

Pav

emen

ts

Coa

tings

Land

scap

ing/de

cora

tion

Electric

al &

Mec

hanica

l

Parallel w

orks

Gen

eral e

xpen

ces

As-b

uild

Cost (%

)

Paidon Square station

Rizari street station

Cut and Cover Method

Parking Station Total Cost (x103 € )Cost/parking

place (€ )Cost/m2 (€ )

Paidon Hospital Square 5.283 9.170 303

Rizari Street 4.830 7.275 254

Kaniggos Square 9.856 20.075 640

Cut and Cover Method

Cost Analysis – Key issues

Cut and Cover Method

Cost Analysis – Key issues

Factors examined:

Local conditions in the construction area.

Geological background.

Excavation depth.

Parallel works (Rerouting of the traffic, pedestrian passages, rearrangement of utility networks).

Support.

Renovation and landscaping.

Support.

Excavation.

Support.

Excavation.

Room and Pillar Method

General outline

Support.

Natural support.

The pillars of the rock support the overburden.

Field of Application .

Horizontal or slightly inclined formations , located in low to medium depth and characterised of high to medium strengh.

Parking Station Surface (m2) Volume (m3) FloorsCapacity

(cars)

Agia Paraskevi 13.248 66.240 1 360

Tourkovounia 11.319 45.276 1 346

Katehaki Bus depot 59.917 479.336 1284

(buses)

Room and Pillar Method

Cases examined

Entrance –Exit of Pedestrians

Entrance – Exit of Vehicles

Agia Paraskevi

Parking Station

Room and Pillar Method

Cases examined

Cost Analysis – Key issues

Major cost components

Excavation cost.

Development cost.

Income gained from the sale of the raw materials.

Parking Station Total Cost (x103 € )Cost/parking

place (€ )Cost/m2 (€ )

Agia Paraskevi 1.353 3.760 102

Tourkovounia 3.067 8.865 297

Katehaki Bus depot 3.667 12.910 61

Factors examined:

Location.

Volume.

Excavation method.

Room and Pillar Method

Creation of an economy of scale.

Comparative evaluation

Much lower cost/m2 in the room and pillar cases than ofthe cut and cover ones due to:

Revenues from the raw materials sales.

Natural support absence of major support systems andconcrete works.

The room and pillar method constitutes a radical solution which is able to offer the optimal financial results.

Agia Paraskevi

102

Τourkovounia

297

Paidon Hospital

Square

303 Rizari Street

254

Kaniggos Square

640

Katehaki

Bus Depot

61

0

150

300

450

600

750

Tota

l c

ost

(€/m

2)

Hospital Paidon Square

Rizari Street

Kaniggos Square

Agia Paraskevi

Thermal Bus Company

Τourkovounia

Conclusions

The development of underground car parks is essential for modern cities as it provides an efficient way to facilitate the parking needs.

A further research should be realized in order to construct underground parking stations using methods which combine feasibility with greatest economy.

End of Presentation

Thank you very much!