Abstract:
The NERD center floor slab system was introduced by late Dr. A.N.S. Kulasinghe in early 1987 specially
for domestic buildings which are used by middle income families in Sri Lanka. The invention of NERD system
directed to identify cost effective slab construction system relative to conventional slab system and also the use of
un-propped construction technique and reduction of depth of slab caused to reduce construction time and material
required for construction activities. The NERD system consists with 50 mm thick in-situ concrete slab retain on
trapezoidal shape pre-stressed beams which are placed by keeping 600 mm interval between each. Although, the
concept of NERD system is being widely adapted in domestic building construction exposed beam under the soffit
of the slab keeps away people from the use of NERD slab system. Therefore, this research has been given much
more advertency to make it as flat soffit slab with the improvement of structural arrangement of the NERD system
such a way that changing the shape of pre-stressed beam and thickness of in-situ concrete slab with hollow
arrangement to reduce utilized concrete of the slab.