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INTRODUCTION The proposed cricket stadium is
located in Providence, Guyana and shall be
constructed as per the ICC norms for the World
Cup to be held in 2007. The stadium of 15,000
capacity is to be constructed under the Ministry
of Public Works and Communications with a grant
from the Govt of India. This design basis report
is drawn only for the structural design of the
works in the stadium complex project.   As
listed in the Architectural basis, there are
various buildings in the complex, which serves
the requirement for the intended capacity. The
report tends to highlight the general design
philosophy adopted in the structural design of
the elements and also gives an overview of the
basis of structural analysis and design adopted
to arrive at the estimate. The report also
highlights the various methods and loads assessed
for the purpose of structural design of elements.
It also brings out the reason for adopting
various principles chosen for design and gives a
comprehensive list of the codal provisions
chosen. At the end the list of codes adopted for
design is furnished. All materials shall be as
per the Indian standards and design shall comply
with BS standards as listed below. The Indian
Standards are also listed for clarity.
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 DESIGN PHILOSOPHY   The main buildings in the
stadium complex are the stands, members and
player's pavilion block, venue operating centre,
media centre and landscaped seating stand apart
from service buildings and underground
structures. The structural system adopted for
the buildings are concrete/structural steel
framed conventional beam slab and column
structures on pile caps over bored cast-in-situ
concrete piles/pre-cast concrete piles/green
heart timber piles. The slabs are proposed in
composite construction with concrete on profiled
metal decking (serving as reinforcement). The
stands are designed with pre-cast bleachers on
raker beams in concrete/structural steel. The
roof covering the stands are designed with
structural steel elements in profiled sections to
match the architectural form. The columns in
cast-in-situ concrete/structural steel have
insert plates/base plates to seat the
roof-supporting member. The structures are
analysed for dead load, live load and wind loads
as per the codal provisions. Waterproofing on
concrete surfaces exposed to atmosphere is done
with reinforced modified bituminous membrane and
is protected by cement concrete tiles. The
waterproofing of sunken slabs in toilets is also
achieved with the same material. All structural
steel surfaces are protected from corrosion with
anti-corrosive paint.   DESIGN LOADS Dead
Loads The self weight of the various elements
are computed based on the unit weight of
materials as given below
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 Imposed Loads As per BS6399 (Part 1)-1996 the
building is classified as Public Assembly
building. The superimposed loads or otherwise
live load is assessed based on the occupancy
classification as per BS6399(Part 1)-1996 for
assembly building. The imposed loads (in kN/m2)
considered are as listed below
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On flat roofs, sloping roofs and curved roofs
with slopes up to and including 10 degrees, the
imposed loads due to use or occupancy of the
buildings and the geometry of the roofs are given
below As per cl 6.2, BS6399 (Part 1)-1996 a)
For roofs with access provision 1.5 b) For
roofs without access provision 0.75  
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On sloping roof of slope greater than 10o, as
per clause 6.3 of BS6399(Part1)-1996 the imposed
loads (kN/m2 of the plan area) that are likely
to act permanently are as follows Waterproo
fing 1.5 (On roof / terrace) Partitions 1.0 (wh
erever applicable) False ceiling 0.5 wherever
applicable) Structural slab shall be sloped
suitably to avoid achieving requisite slopes with
screed/brick bat coba Bleachers are
designed to resist a horizontal force applied to
seats of 3.0 kN per linear meter along the line
of seats and 1.5 kN per linear meter
perpendicular to the line of seats. Wind
Load The wind pressure is calculated based
on the data furnished below and as per the
provisions laid in BS6399 (Part 2)-1997 Basic
Wind speed 50m/sec (As assessed from
UBC) Maximum gust 30mph (13.5m/sec) As
given Mean probable 50 years DESIGN LIFE
OF STRUCTURE Building Type factor Kb 1.0
Ground roughness category town Built up
areas with an average level of roof tops at least
Ho 5m above GL Dynamic Augmentation Factor
Cr 0.03
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Static Simplified method is used for design for
wind loads with the following parameters as per
cl 2.2 BS6399 (Part2)-1997   Directional Factor
Sd 1.0 Altitude Factor Sa 1.0 Seasonal
Factor Ss 1.0 Probability Factor Sp
1.0 Site Wind Speed Vs Vb x Sa x Sd x Ss x Sp
50 x 1 x 1 x 1 x 1 x 1 50m/sec Effective
Wind Speed Vs x Sb Where Sb is the terrain
and building factor obtained from cl 2.2.3.3 of
BS6399(Part2)-1997 Earthquake Load Guyana is
not within the earthquake belts and also does not
figure in the places listed in the seismological
active zones. It has been mentioned that Guyana
experiences tremors every 5-10 years. Earthquake
loads are not considered for analysis and design.
With the given conditions it is assumed that the
wind load on the structure would be sufficient
for the lateral loads that would be generated
during the tremors.
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Load Combinations Primary loads are combined in
accordance with relevant stipulations in
BS8110(Part 1)-1997. The combination that
produces the most unfavourable effect in the
building, foundation or structural member
concerned is adopted for design.
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Eartha and Waterb Pressure 1Dead and Imposed
(and earth and water pressure) 2Dead and Wind
(and earth and water pressure) 3Dead and Imposed
and wind (and earth and water pressure aThe earth
pressure is that obtained from BS8002 including
an appropriate mobilisation factor. The more
onerous of the two factored conditions should be
taken. bThe value of 1.2 may be used where the
maximum credible level of the water can be
clearly defined. If this is not feasible, a
factor of 1.4 should be used. cUnplanned
excavation in accordance with BS8002, 3.2.2.2
not included in the calculation. dUnplanned
excavation in accordance with BS8002, 3.2.2.2
included in the calculation.
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ANALYSIS METHOD   The analysis of the structure
is carried out using the STAAAD Pro-2003.
Appropriate loads and its combinations, as per
relevant clauses in BS codes as described in this
report are chosen for analysis and design.
Precast elements are analysed manually for
handling, transportation and service
stresses.   DESIGN LIFE   The design life of the
structure is considered as 50 years. This
requirement is not applicable for replaceable
materials.   DESIGN METHODOLOGY   All structural
elements shall be designed according to the Limit
State Method as specified in BS8110 for
reinforced concrete elements and BS5950 for
structural steel elements.   FOUNDATION   As per
recommendations of the soil investigation report,
only piles are considered as foundations. The
various types of piles considered for supporting
load-bearing columns/structures are bored
cast-in-situ concrete piles, pre-cast concrete
piles and green heart timber piles. The vertical
capacity of the pre-cast concrete piles of 20m
length is 34mT and that of 23m green heart timber
piles is 18mT.  
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CONCRETEThe grade of concrete and type of cement
adopted for the various structural
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REINFORCEMENT  For all structural RC elements
steel reinforcement used shall be of Fe 415 grade
conforming to IS1786-1985 or equivalent. NOMINAL
COVER TO REINFORCEMENT  The cover to concrete
shall be as per the guidelines laid in cl 3.3 of
BS8110 Part 1-1997. The cover shall also
satisfy the requirements of 2h fire
rating.   DESIGN STANDARDS The relevant
Standard codes, as given below, have been
followed for structural design
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