DESIGN LOADS & STRUCTURAL

COMPONENTS

Unit-1

.The loading of a building structure can take on a wide variety of forms.

.Loads can usually be considered to be either Primary or Secondary.

DEAD LOADS

LIVE LOADS

WIND LOADS

SNOW LOADS

EARTH QUAKE LOADS

HYDROSTATIC & SOIL PRESSURE

IMPACT LOADS

1.1 Design Loads

1.2 SHEAR WALLS-Shear Wall Is A

Structural Element Used To Resist

Lateral/Horizontal/Shear Forces Parallal To The Plane Of The Wall By:

- Cantilever Action For Slender Walls Where

The Bending Deformation Is

Dominant Truss Action For

Squat/Short Walls Where The Shear Deformation Is

Dominant

A TYPICAL CADD DRAWING SHOWING SHEAR WALLS IN A BUILDING PLAN

Stresses for design should be calculated for the most sever combinations

of loads and forces. Four load combinations are generally considered important

for checking for adequacy of the bridge.

1.3 LOAD COMBINATION…..

S.No. Load Combination

Loads

1. Stresses due to normal loads

Dead load, live load, impact load andcentrifugal force

2. Stresses due to normal loads +occasional loads

Normal load as in (1) + wind load, other lateralloads, longitudinal forces and temperaturestresses

3. Stresses due to loads during erection

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4. Stresses due to normal loads +occasional loads + Extra-ordinary loadslike seismic excluding wind load

Loads as in (2) + with seismic load instead ofwind

Table:1Load combinations

1.4 FRAMED TUBES AS THE HEIGHT OF BUILDING

INCRESES (ABOVE THIRTY FLOORS) , THE EFFECT OF LATERAAR L LOADS BECOMES INCREASLY INTENSE. IN SUCH A SITUATION THE USE OF TUBE SYSTEM HAS BEEN FOUND ECONOMIAL.

SHEAR WALLS CAN BE MADE OF Rcc , STEEL, COMPOSITE, AND MASONRY.

FRAMED TUBE STRUCTURE

FRAMED TUBE

TRUSSED TUBE

TUBE IN TUBE

BUNDLED TUBE

Examples

WINGS MUSEUM(A PROTOTYPE)Tube in Tube

WORLD TRADE CENTERU.S.A.Framed Tube

WATER CUBECHINA Trussed Tube

WILLIS TOWERCHICAGOBundled Tube

It is the ratio between the height of the building & the width of the building.

1.5 ASPECT RATIO…..

1.6 OVERTURNING RESISITANCE

WHEN A BUILDING IS SUBJECTED TO A LATERAL LOAD ,IT DEVELOPS A OVERTUTRNING MOMENT ON BUILDING.TO RESIST THIS OVERTURNING MOMENT THERE IS A RESISTING MOMENT ON BUILDING TO OPPOSITE TO OVERTURNING MOMENT. SO THE BUILDING CANNOT OVERTURN DUE TO OVERTURNING.,

Overturning resistance developed in a house.