COFFER SLAB AND BEAM DESIGN

COFFER SLAB AND BEAM DESIGN 

Nowadays, in the construction field, there are tremendous new technology and techniques used to give a decent look to the building so that the people get attracted to the buildings and it will give the dealers and buyers to get through it. In this modern organization, the people demand that they have an innovative and creative design of the building for the aesthetic point of view. This paper represents that in the commercial building for the architectural consultant to design and shape by the coffer slab with different types of molds used as per the drawings that are required by the client perspective and overview.

About The Author:

Sp.Aswinpalaniappan.,DCE.,B.E., M.E.,(Structural)

Slab Length	8.56	m
Slab Width	16.17	m
Thickness of slab	0.10	m
Concrete Grade	M25	N/Sq.mm
Concrete Grade	25	N/Sq.mm
steel Grade	Fe500	N/Sq.mm
steel Grade	500	N/Sq.mm
Spacing of Rib (s)	1	m
Dimension of Slab & Beam
Depth	0.428	m
D	450	mm
Width of Rib	200	mm
1. Load Calculation
Weigt of Slab	2.50	Kn
Total Load of slab	346.04	Kn/m
Weight of Rib	1.75	Kn
Total Load of Beam in X-Direction	104.86	Kn/m
Total Load of Beam in y-Direction	424.46	Kn/m
Total Weight of Floor Finish	207.62	Kn/m
Total Weight of Live load	0.00	Kn/m
Total Load(W)	1082.98	Kn/m
Load per Sq.m(q)	7.82	Kn/Sq.m
2. Approximate Method(Moment)
q1	7.25	Kn/Sq.m
q2	0.57	Kn/Sq.m
moments in x & y direction @ center of grid for 1.0 width taken as
Mx	66.44	Kn.M
My	18.62	Kn.M
Qx	31.05	Kn
Qy	4.61	Kn
The approximate method neglect the twisting moment in the grid
maximum working moment	66.44	Kn.M
moment resisted by central rib in x-direction over 1.0m width	66.445	Kn.M
Ultimate moment	99.67	Kn.M
Muf	331200000000.0
	331.85*10^6	Kn.M
Since Mu lessthan Muf
Neutral axis fall within the flange
	811.391	Sq.mm
provided 4 bars of 20mm diameter (Ast=1255Sq.mm)
maximum working moment	18.62
moment resisted by central rib in y-direction over 1.0m width	18.62
Ultimate moment	27.93
	227.383	Sq.mm
provided 2 bars of 16mm diameter (Ast=402Sq.mm
maximum ultimate shear	6.91	Kn
Tv	0.07	N/sq.mm
Assuming two bars to be bent up near support	982	Sq.mm
100ast/bd	1.09
Tc	0.62	N/sq.mm