The objective of
this project was creation of an engineering solution for
the multifunctional shopping complex, which the customer planned to build in
the area of crossing of four lively highways connecting the densely populated
district with the centre of city and with exit roads to the suburbs. The
shopping complex was to be placed near the underground station with a high
passenger traffic flow and should have direct passenger communication. The
complex should have a multistory underground car park, an overground zone for
shops and offices with total square of more than 47500 sq.m. (including 21500
sq.m. for lease). At the moment of the beginning of designing, transport
situation was complicated in the area of object placement, and the traffic
organization scheme needed to be fully revised.
The
work aimed at project creation of an object with a parking and office
area, which would fall in with the existing building development and have direct communication with the
underground station hall.
Background
At the same time, a traffic management scheme
had to be changed to increase traffic capacity in this transport node. The
designing bureau was a general contractor, which took a responsibility for
development of the architectural and construction part of the project. This
company hired me especially to create a new traffic management scheme and to
design the technological nodes of the parking and the underground zone. The
decision was based on my previous experience in development and construction of
the cast-in-place and precast concrete reservoirs, where the modern methods of
buried walls construction were used, and also considering my specialized
education in traffic management field.
On
the one hand, my part of the work consisted in searching for original designs
of the underground part of the complex, which had to be attached to the
overground part; on the other hand I had to integrate the parking in a new
scheme of automobiles and pedestrians traffic management. Thus, my obligations
included: prototype analysis and engineering design of the underground parking
with 400 places capacity for the multifunctional complex; selection of
necessary methods to build the underground part, considering proximity of a
railway station; adoption of a traffic scheme in the construction area to new
conditions during construction (a temporary scheme) and its posterior
modernization for traffic flow optimization after the construction finished;
author’s supervision during construction for prompt solution of arising
problems and design choices development.
All necessary strength calculations and calculation of
elements and underground structures, rough construction estimate, general
drawings of the building and original (non-typical) technical solutions I made
by myself. Drawings of typical nodes and all standard calculations were made by
general contractor’s specialists. Also I provided the required calculation to
substantiate necessity of changes in the traffic management scheme for
approvement in the supervisory bodies. Some corrections were added by the
specialists of the Traffic Management Committee.
Solution
At the first stage, before design starts, it was
necessary to select a proper traffic management scheme and choose a certain
place for multifunctional centre placement on the proposed site (master plan
development). I have analysed transport density and traffic capacity of the
existing roads and crossings in the construction area and have drawn a
conclusion that the best traffic management scheme here will be a circular
(roundabout) traffic scheme.
Hence,
the task was to place the parking within the bounds of this ring, providing
access for the pedestrians to the main building from the underground station
hall as well as from the overground crosswalks. Motor vehicles should enter the
parking from the ring-road as well, and it was necessary to minimize obstacles
for transit transport caused by route change and speed down of the vehicles
entering the parking. In this case I used my knowledge of traffic management
acquired during my study at the State University of Architecture & Civil
Engineering at the Road Traffic Management Department. Firstly, I have
developed a temporary traffic scheme for the whole period of construction.
After that, I developed a perspective scheme of road node (road interchange)
reconstruction and a permanent traffic management scheme after termination of
the construction, considering traffic intensity increase.
After
the position of the shopping centre had been determined, and it had been
decided that the complex should have a cylindrical form, I made comparison of
different types of underground parkings, which could be used under the given
conditions, on correlation between cost and total area to square and number of
car spaces. During the analysis, all existing garages were divided in two
groups – with inclined or spiral ways for entry/exit and with lifts. The
garages with inclined floors could not be used here, because they imply
primarily a rectangular form of building and may cause holdups under restricted
conditions in rush-hours. The garages with spiral floors mean construction of
separate descents, which are expensive in underground construction and restrict
the number of additional parking places. The garages with lifts are very
expensive and decrease traffic capacity, as queues of vehicles will stand on
the ring in wait for
entry.
So,
I decided to adopt my invention patented in Russia (RU 2129197) - “Multilevel
garage complex“, as in this case there is an opportunity to use space for
parking to the maximum, it is simple and cheap in underground construction, it
is easily adjusted to the ring
traffic scheme.
This is a constructive solution, where building
consists of two coaxial (one inside another) vertical caissons. Between
caissons walls on the floors there are separate parking places and access ways
to them – two symmetrical (left and right) spiral roads, leaning on
external (or internal) building walls from the one side, and on the supporting
reinforced concrete pillars from the other side. One road passes along the
parking spaces at external caisson walls, and the other - along the
parking spaces at internal caisson walls. Roundabout inside the garage is
realized only in one direction, which increases traffic safety. There are
common traffic sections (areas) in the places of junction of the symmetrical
spiral roads to each other (two junctions per a circle, as the internal and
external spirals differ: one is left and the other is right). These sections
serve for change of direction from ascent to descent and vice versa (if
necessity arises).
This solution also
allows to use the central part of the underground garage for additional parking
as well as for rented spaces.
To integrate the underground parking into the existing
ring traffic, two semicircle roads with a single path go from the underground
building to the ring area: one for entry (descent) to the garage and the other
for exit (ascent) from it. A top mark of the underground part of external walls
coincides with a lower mark of concrete road surface on ring traffic area,
and overall depth of the garage (18 m) allowed to develop four levels of
parking places to achieve the required capacity.
In order to prevent crossing of the main stream of visitors with traffic flow, I have designed a pedestrian subway sizes
12mx4m of specified width through the parking form the underground station hall
and another subway nearby.
Also I have provided recommendations for further
calculation of ventilation and air-conditioning systems, storm drainage and
groundwater drainage systems.
As generally construction of the parking was
unconventional, during the development, besides the AutoCAD/Revit program, I also used the APM Civil Engineering
automated calculation and construction design system and the APM Structure3D
module for project and checking calculation of reinforced concrete
constructions, creating the stress map, strength and dynamic analysis of parts
by FEM. The rest of typical nodes and
overground part were calculated by specialists of the project contractor company.
Relying on the geological engineering survey data in
the construction site obtained from a company-builder of underground stations,
I decided to use a caisson method as the cheapest for construction of external
walls.
After that, I made calculation of rock
steadiness, chose a type of shore for the caisson, and also determined main and
additional loads on the shaft collar shore from the buildings and structures
surrounding the construction site on surface.
Thereafter, I elaborated a detailed work performance
plan and gave a complex assessment of probable consequences of construction for
the neighbouring buildings. Here I used my previous experience in buried
structures calculation obtained during designing of drinking water storage and
filtering reservoirs.
After designing and project approvement had been
finished, I began to provide author’s
supervision over building erection. Special attention was given to caisson sinking (external walls) and prevention of sinking irregularity (lateral
inclination), providing regular geodesic control.
After
the external caisson wall had been built, I provided control over reinforcing and
concrete works during erection of monolithic internal cylindrical walls,
pillars, floors - symmetrical spiral roads. To erect the internal cylindrical wall, I have
developed a method of using self-propelled plants of horizontally sliding
formwork (a rail carriage with pillars
and a winch for shield lifting),
which would move on a round rail way for concreting of internal caisson
walls. This method is economically rational for large diameter of ring, as is
in our case.
The
floors have been built using reusable formwork systems produced by “Peri”
(Germany), as in this case every formwork set was individual for each part of
the building. That is why I have projected them in RUMBA, a computer program
for formwork selection and three-dimensional arrangement, and then they were assembled and mounted at the
site.
Upon construction termination the new circular traffic
management scheme proved its efficiency, as measurements have shown increase of
intersection capacity in general. This allowed to avoid holdups in rush hours
and queues at node access way, despite the fact that density has increased by
2.5 times in the result of construction of such building.
Summary
Successful accomplishment of construction has shown
that the goal to integrate the multifunctional complex with the underground
parking into the traffic circle had been achieved. Also underground space under
a high-density area has been used efficiently, and the traffic management
scheme has been improved. These results were produced due to the deep analysis
of collected data on transport unit and application of relevant methodologies
related to traffic capacity computation and traffic volume planning. My role in
the project consisted in designing and full engineer’s development of the
underground part of the object. I used my inventions, adapted and used the
modern methods of underground construction. As a result, I have acquired
additional knowledge of underground construction, which I used during designing
as well as control over building erection.
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