unispan floor slabs

DESCRIPTION The Unispan flooring system

consists of a series of 75mm

thick precast, prestressed

concrete slabs with a reinforced

concrete topping.This composite

construction allows clear spans

of up to 8.0 metres. SIMPLE Most contractors agree that

Unispan is a simple form of

construction. Slabs are typically

1200mm wide. FLEXIBLE Unispan is easily adapted to any

floor plan and individual slab

widths can be custom made to

suit individual requirements.

Service holes can be allowed for

in the slabs. Please check

with Precast Office

SURFACE FINISH The slabs are cast on a steel

mould and the soffit is flat.This

means that Unispan may be left

untreated, painted or decora-

tively sprayed to match colour

schemes. Painted surfaces

may require a thin plaster coat. SOUND TRANSMISSION A major practical benefit of a

concrete floor is its ability to

reduce noise transmission. Unispan concrete floors are

quiet and do not creak with

temperature and moisture

changes. The table below

shows sound transmission

ratings achieved by Unispan.

CANTILEVERS Cantilevered balconies and decks

can be created by using Unispan

to form the soffit of the slab. TRANSPORT Unispan slabs must be handled

and stacked at two points, by, or

directly beside, the lifting eyes. ERECTION It is recommended that Unispan

slabs be seated 75mm onto the

supporting walls/beams and

bedded on wet mortar or plastic

bearing strips to ensure an even

bearing at the correct level.

UNISPAN TYPICAL UNISPAN SECTION

Unispan floor to

enable rapid

construction and a

quick usable floor

area.

UNISPAN LOAD/SPAN TABLE (indicative only) Safe, superimposed live load in kilopascals (kPa) for various topping thicknesses (assuming no superimposed dead load, i.e. SDL=0kPa).

Span (m) 3.5 4.0 4.5 5.0 5.5 6.0 6.5 7.0 7.5 8.0

65mm topping 17.0 13.0 9.0 7.0 5.5 3.5

75mm topping

15.0 11.0 8.0 6.0 4.0

3.0

90mm topping 14.0 10.0 7.5 6.0 4.5 3.5

110mm topping

10.0 7.0 6.0

3.0 2.0

4.0

130mm topping 9.0 8.0 6.0 4.0 3.0

Spans to the right of the bold (zig zagged) line exceed the maximum recommended span/overall depth ratio of 44. For spans exceeding this value, please check with Precast Office.

UNISPAN SECTION PROPERTIES Section properties are based on a 1200mm wide section of floor. The modular ratio for topping concrete is assumed to be 0.71 for 20MPa concrete for calculating the composite section properties A, Yb, I, Zb, and Zt. Area x10

3 mm

2 Yb mm Ix109 mm

4 Zbx106 mm

3 Ztx106 mm

3 1200mm wide mass kg/m weight kPa Bare unit 90 37.5 0.042 1.12 1.12 230 1.88

With 65mm topping 145 64 0.230 3.61 3.03 430 3.51

With 75mm topping 154 68 0.283 4.15 3.44 461 3.77

With 90mm topping 167 75 0.377 5.02 4.18 507 4.14 With 110mm topping 184 84 0.532 6.31 5.25 568 4.64

With 130mm topping 201 94 0.723 7.72 6.54 629 5.15

Unispan floors were

used along with

precast Shell Beams. A

lap pool, lagoon pool,

spa, gym and sauna

TYPICAL UNISPAN

SEATING DETAILS

ON BLOCK WALLS

AND STEEL BEAMS

unispan FIRE RESISTANCE RATING Standard Unispan can

provide up to a 1.5 hour FRR. MATERIALS Unispan slab strength = 40

MPa at 28 days. Topping = 20 MPa at 28

days (as required by NZS

3101:1995).

FURTHER TECHNICAL INFORMATION Specifications for the

manufacture, transport and

erection of Unispan, and standard

details for typical situations, are

available from our Precast Office

Experienced and qualified staff

will be pleased to discuss design

and fixing details.

Concrete Solutions (Fiji) Ltd Phone: +(679) 336 4169

Fax: +(679) 336 4175

Mobile: +(679) 9929224

Web:

www.concretesolutionsfiji.com