The Polyvalent Hall in Cluj-Napoca, Romania is a multi-purpose indoor arena that holds up to 10,000 people. The building features a 63.9 meter clear span roof structure composed of pre-stressed concrete beams and a space truss system made of steel square hollow sections. The structure was erected in four phases, beginning with cast in place concrete columns and precast elements, followed by erecting the steel trusses and bracing, then installing precast elements under the playing field, and finally installing the roof and facade.

1. LONG SPAN STRUCTURE
MULTI-FUNCTIONAL SPORTS HALL
ROMANIA
POLYVALENT HALL
M.Akhil
1130100370
Sec - A

2. Clear Span : 63.90m,
Total Length :76.10m

3. LOCATION : Sala Polivalenta, Strada Uzinei Electrice, Cluj-napoca
400000, Romania
ARCHITECTS : Dico Si Tiganas
ARCHITECT IN CHARGE : Șerban Tiganas, Florin Dico, Alexandrina Kiss, Camelia Gaz
DESIGN PARTNERS : Plan 31 Ro, Instal Data Proiect
AREA : 38500.0 SQ.M
PROJECT YEAR : 2014
"DICO AND TIGANAS" - A PARTNERSHIP
BETWEEN AN ENGINEER AND AN
ARCHITECT OF CIVIL

4. The Polyvalent Hall is a multi-purpose indoor arena in Cluj-Napoca, Romania. The venue holds 10,000 people
in its largest concert or boxing configuration, 7,308 for basketball and handball. The building is located next to
the Cluj-Arena.
INTRODUCTION
Large Span Space Trusses; Precast Concrete; Joint Analysis.
The building has 115m x 130m in plane dimensions, As they need to work in winter (temperature less than 4˚ )
which caused concrete shrinkage after hardening. They opted for the usage of pre stressed concrete elements
Where the design loads resulted in great reaction forces there were used pre stressed concrete beams with cast
in situ concrete columns, while for the rest of the elements were pre casted and fixed with dry or wet
connections.
The 64m span roof was first thought to be designed as several laminated wooden arches. As the
entrepreneur have neither the possibility nor the technology to build these type of elements, a new
solution was brought and that was a space truss with SHS.
SQUARE HALLOW SECTIONS (SHS)

5. All frame beams and stair beams are pre casted, reinforced concrete or pre
stressed concrete. The beam-column joints are moment-resisting and pinned for
the upper levels. For the frames connected directly to the roof`s steel truss, rigid
connections have been used for the beams which are in the same plane with the
space truss.
The slab consists in a precast part and a topping of 80mm thickness of C25/30
concrete, and S500 reinforcing steel. In order to assure enough stiffness to the
vertical loads, and also to assure a horizontal rigid diaphragm effect. For a better
connection between the partially precast slab and the beams, hollow-core units
were partially cut off at the edges and extra reinforced with triangular skeleton
reinforcing; where pre slabs were used, only the meshing wires in the topping
were enough but connectors left out of the pre slabs surface for better joinery.
STRUCTURE

6. The roof structure consists in 7 trusses with a clear span of
63.90m, and total length of 76.10m, supported by concrete frames
and lateral interconnected with the rest of the structure through
horizontal and vertical steel bracings. The space steel trusses are
mounted using a spacing of 10.50m. Design of this roof structure
solution has been driven by a number of factors including the
span, roof geometry, load to be supported, economy and
aesthetics. The truss section is 3600 mm wide and approximately
4000 mm deep.
ROOF TRUSS DESIGN

7. Providing pinned supports for the roof trusses, positive effects in the internal effort distribution and
the highest horizontal reaction over the concrete structures, were obtained. The use of simply supports for the
roof trusses eliminates the horizontal reaction over the concrete structure, but has a negative influence over the
roof trusses in terms of vertical deflection and effort distribution.
Final solution for the connection considered a combination of both effects: a limited sliding possibility
of the support, used only for the erection phase of the structure (mainly deformations caused by the permanent
actions are consumed), after that the support is transformed in a perfect hinge.
In this way a lower horizontal support reaction resulted, consuming around 30 mm horizontal
displacement by the sliding possibility of the support, from the total of 80 mm, calculated under permanent,
technological and snow loading.
JOINTS BETWEEN THE STEEL AND CONCRETE STRUCTURE

8. The ratio of utilization for the members, following the general method of EN 1993-1-1 resulted in less than 80%
his way, while considering the simply supported configuration of the roof truss structure the level of 100% is
achieved. After conducting global stability checks and joint checks of the space steel structure. Some of the
joints in the truss were altered and redesigned
JOINERY CHECKS
Before After

9. PLAN,
VIEW,
SECTION

10. STRUCTURE`S ERECTION STAGES
The structure erection stages are:
Phase I – cast in situ columns together with the precast elements (columns, beams, slabs) are erected till the roof
level, while the area beneath the playing field remains at the foundation stage in order to be able to accomplish
later the steel roof structure from inside and from outside the building perimeter;
Phase II – erecting work of the space steel trusses and mounting the bracings;
Phase III – mounting the precast elements(several short columns, pre stressed beams and concrete hollow-core
units) underneath the playing field as well as around the site, till ±0,00m level is reached;
Phase IV – installation of the roof and façade envelope.
The first frame is cut into five parts and brought to the site, as it is too expensive the remaining trusses steel
members were brought to the site and welded into frame