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1. Floor Systems and Roof Slab System

• Flat Slab- are rectangular slab directly supported by columns without

beam or girders. The slab is either uniform in thickness or provided with

aquare symmetrical area directly above the column reinforced with bars

running in two directions. The increased area directly above the column

iscalled rop !anel or simply rop. "ikewide# a flared head is employed in

the construction of a flat slabe floor making a capital of the column.

• Flat !late- when the column design $s not provided with capital# a straight

flat underneath is provided in the slab throughout the system. The slat

slab floor system is generally economical not only in terms of materials but

also labor. $t is the most suitable type of construction for industrial

buildings having a wider live load and also for buildings where the use of 

capital is not ob%ectionable.

• Ribbed Floor Slab-an economical type of flloor construction applicableonly

to medium span with light or medium load. & ribbed floor slab conists of 

small ad%acent T-'eam wherein the open spaces between the ribs are

filled with clay tile# gypsum tiles or steel forms. (enerally# the tilesmeasure )*+,*cm with 1*#1# *# # )* and /*cm placed at /*cm on

center making the ribs 1*cm wide.

• 0affle Slab- & waffle slab is a type of building material that has two-

directional reinforcement on the outside of the material# giving it the shape

of the pockets on a waffle. This type of reinforcement is common on

concrete# wood and metal construction. & waffle slab gives a substance

significantly more structural stability without using a lot of additionalmaterial. This makes a waffle slab perfect for large flat areas like

foundations or floors.

The most common material for a waffle slab is concrete. These slabs are

used as the foundation for many different types of buildings and

structures# but are most common in commercial or industrial buildings.

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0affle foundations are resistant to cracking and sagging and can hold a

much greater amount of weight than traditional concrete slabs.

• "ift Slab- 

a method of constructing concrete buildings by casting the floor

or roof slab on top of the previous slab and then raising %acking2 the slab

up with hydraulic %acks# so being cheaper and faster as not requiring

bo+ing and supports for casting in situ.3ohnstone 4all# a 5lemson

6niversity dormitory in 5lemson# South 5arolina# was erected using this

method in 1,/. Several of the blocks have now been demolished# and

campus legend says that that two other similar structures built elsewhere

collapsed before completion. "ift slab construction was also involved in

the "7&mbiance !la8a collapse in 'ridgeport# 5onnecticut# in 1,9:# and

resulted in a nationwide federal investigation into this constructiontechnique in the 6nited States# and 5onnecticut imposed a

temporary moratorium on lift slab construction.

• Span Sterss Floor System- The 6nispan flooring system consists of a series of 

:mm thick precast# prestressed concrete slabs with a reinforced concrete

topping. This composite construction allows clear spans of up to 9.*metres. ;ost contractors agree that 6nispan is a simple form of

construction. Slabs are typically 1**mm or /**mm wide. 6nispan is easily

adapted to any floor plan and individual slab widths can be custom made to

suit individual requirements. 'alconies and decks can be created by

cantilevering the slab up to ***mm# while including a weather step at the

building line. 6nispan slabs must be handled and stacked at two points# by# or

directly beside# the lifting eyes. $t is recommended that 6nispan slabs be

seated :mm onto the supporting walls<beams and bedded on wet mortar or

plastic bearing strips to ensure an even bearing at the correct level.

• Slip Form ;ethod- $t is a method of vertically e+truding a reinforced

concrete section and is suitable for construction of core walls in high-risestructures = lift shafts# stair shafts# towers# etc. $t is a self-containedformwork system and can require little crane time during construction.

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This is a formwork system which can be used to form any regularshape or core. The formwork rises continuously# at a rate of about

)**mm per hour# supporting itself on the core and not relyingon support or access from other parts of the building orpermanent works.

5ommonly# the formwork has three platforms. The upper platformacts as a storage and distribution area while the middle platform#which is the main working platform# is at the top of the pouredconcrete level. The lower platform provides access for concrete finishing.

. 0all !anel Systems

• Flat-Type

• Ribbed Type

• 0indow Type and 0all Type

• Tilt-up 0all !anel System