Cen 479 ppt (2)

Post on 22-Mar-2017

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Group:12

Modules of RuptureIt is the ability of material to resist

deformation due to applied load.

fr = 6Mu/bh²Here,fr represents the apparent maximum stress.Mu represents the ultimate bending moment.h = depth & b = width

stress-strain graph :

Fatigue Deformation due to cyclic loadA good example of fatigue failure is breaking

a thin steel rod or wire with our hands after bending it back and forth several times in the same place.

Internal forces of a member under fatigue loading

CreepThe tendency of slow deformation under long

term load.Actually it is the permanent deformation due

to mechanical stress.Slow deformation of a material over

considerable length of time at constant load.

Shrinkage It is the time dependent strain measured is

an unloaded and unrestrained specimen of constant temperature.

The decreasing dimension or volume of material as a result of change in temperature.

Due to drying or loosing of water ,concrete under goes change in volume this is called shrinkage.

Equation

Shrinkage Failure

Flexural Member The member in which stress would be

developed due to force and moment.

Service LoadService Load is the actual load ,not usually

factored .Maximum intensity of load expected during

the life span of the structure known as service load.

The total load and live load subjected to the structure during its service life.

Corrosion Corrosion involves the interaction(reaction)

between a metal or alloy and its environment. Corrosion is affected by the properties of both the metal or alloy and environment.

Corrosion by chemical action , specially oxidation called corrosion.

Serviceability Serviceability mainly based on elastic theory

with stress in both concrete and steel assumed to be proportional to strain.

Crack When thin line appear on a member surface ,

is called crack.Crack is the progressive and localized

structural damage that occur due to applied load.

Deflection Ratio of change in length to the original

length.The degree to which a structural element is

displace under load.Change in position of a structural member in

both x and y direction from its original position.

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