Loads acting on Structures- TYPES

1.Dead load
The load of the structure itself is called dead load and different types of the loads which includes in it are load of the structural system, such as walls, columns, slabs, weight of other permanent material such as HVAC, beams etc…
The weight of dead load can be easily calculated by measuring or identifying the unit weight of the material and its dimensions.

2.Live load

All other loads acting on a structure other than dead load is termed as live load.They include all types of movable elements such as furniture, humans etc.. and other types of non-structural elements such as rainwater, snow etc…

3.Dynamic loads

Load that change rapidly or applied suddenly are called dynamic loads.The magnitude of the load will increase based on the dynamic effect.

4.Wind load

The action of wind load is mainly described in IS 875 PART 3
Vz = k1.k2.k3.Vb

  • Where k1 = Risk coefficient
  • k2 = Coefficient based on terrain, height and structure size.
  • k3 = Topography factor
The design wind pressure is given by
pz = 0.6 V2z
where pz is in N/m2 at height Z and Vz is in m/sec. Up to a height of 30 m, the wind pressure is considered to act uniformly. Above 30 m height, the wind pressure increases.

5.Snow Loads (SL)

The action of snow load is described in IS 875 PART 4
The minimum snow load on a roof area or any other area above ground which is subjected to snow accumulation is obtained by the expression
Types of Loads on Structures - Snow Loads
  • Where S = Design snow load on plan area of the roof.
  • Shape coefficient= Shape coefficient.
  • S0 = Ground snow load.

6.Earthquake Loads

The action of an earthquake and its effect are described in IS 1893-2014

Types of loads on Beams

The different load types acting on the beams are

1.Concentrated Loads

A load that acting on the very small area of the surface are called concentrated loads.

2.Uniformly distributed loads

Uniformly distributed loads is a distributed load which acts along the length.We can say its unit is KN/M.By simply multiplying the intensity of load by its length, we can convert the uniformly distributed load into point load.The point load can be also called as equivalent concentrated load(E.C.L).

3.Uniformly Varying load

At a constant rate, the magnitude of uniformly varying load varies along its length.

Triangular load 

In triangular load, the magnitude of the load at one end is zero and the other end is maximum.From zero, the magnitude of the load increases at a constant rate to its maximum value till the maximum end of the span.

Trapezoidal load

In trapezoidal varying load, the magnitude of the load at one end of the span have lower value and that lower value will constantly increase to a maximum value at the end of the span.
The support reactions can easily find out by converting the trapezoid into a triangle and rectangle as shown in the figure.

5.Couple load

The coupled load is two equal and opposite forces acting on the same span.The line of action of both the loads are parallel to each other but in opposite direction.

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