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What is Dynamic Loading? (A Definitive Guide)


Also known as a ‘live load,’ a dynamic load is one that changes in direction, position and magnitude, creating varied forces on a structure. This is different from a static load, which is constant and steady and produces a single response.

For example, if you stand still on a floor, you create a static load, but if you jump up and down and move around the floor, you create a dynamic load.

Types of dynamic load include people, traffic, earthquakes, wind, waves, and blasts. Any structure can be subjected to dynamic loading and the changes that come with a dynamic load can be random, periodic or a combination of the two.

Dynamic loading is best understood with a comparison with static loading.


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Dynamic Loading Vs Static Loading

Dynamic and static loading are both considered in structural analysis, which is concerned with how physical structures behave when subjected to force. These forces can range from vehicles and people to furniture, wind, snow or even earthquakes.

These forces can be either static or dynamic, depending on how they are applied. If the force has enough acceleration compared to the natural frequency of the structure (i.e. they are applied quickly), then they are dynamic. If they are applied slowly, or don’t move at all, then they are static. Dynamic loads are determined with dynamic analysis and static loads with static analysis.

Dynamic loads tend to have a greater impact on a structure than static loads due to the equation of force:

Force = mass x acceleration

As the mass accelerates, so the force increases and the same goes for sudden deceleration.

For example, if you hold a hammer in your hand, it might not be very heavy, but if you swing the hammer and accidentally hit your thumb, it exerts a much greater force.

The F=m x a equation is used in a range of structural engineering applications to determine the force exerted by a dynamic load, such as how much force a roadside barrier should be able to withstand or the maximum weight capacity for a lift.

While dynamic loads, like traffic moving across a bridge or gusts of wind, will change with time, they are often treated like static loads to simplify structural engineering calculations.

So, for example, when working out how much weight a floor can hold in a domestic property, standards institutions may determine a 1.5kN/m2 load applied over the whole floor area, which will take account of potential dynamic forces, such as people dancing or carrying heavy items across the floor, etc.

Materials and Load Tests

All materials have limits with regards to how much tension or compression stress they can tolerate before they yield or permanently deform. These fundamental properties can be tested to find out how much stress a material can withstand. Stress is used as a measure of force per unit area in a cross section of the material. When the force per unit area becomes too much for the material, microscopic fractures develop which can grow as the stress continues to be exerted until the material finally breaks altogether.  The stress level at the point where the material breaks is known as the ultimate tensile strength of the material.

Different materials have different strengths and properties, which help determine the applications they can be used for.


Dynamic loads exist all around us, from our homes and places of work to bridges, roads and even our furniture.

Wind blowing across a bridge as cars travel over it are two examples of dynamic loads being exerted on the same structure. Dynamic loading can also be seen alongside static loading, such as with a crane, whose cab is a static load while whatever weight is being lifted can simultaneously exert a dynamic loading force.


What is the meaning of dynamic load?

A dynamic load is one that constantly changes, such as with the effect of people jumping up and down in a cable car. These changes can be random, periodic or a combination of the two. Dynamic loads are characterised as loads that vary, often delivering greater forces than with static loads as a result.

What is computer dynamic loading?

So far we have spoken on structural dynamic loading, which should not be confused with dynamic loading of computer programs during the runtime of operating systems. This is where a system can dynamically load a library into the memory, retrieve the addresses of variables and functions, and then execute the functions and access the variables, unloading the library from memory. Dynamic loading is one of three mechanisms for a computer program to use other software, along with dynamic and static linking. However, unlike with static or dynamically linked software, dynamic loading allows a computer program to start up in the absence of shared libraries, discover available libraries, and gain potential additional functionality.

What is a dynamic load and what causes it?

A dynamic load is any load that changes over time. These type of loads exert forces onto a structure that are often much greater than their static equivalents. For example, someone jumping up and down will exert a greater force on the floor than someone standing still.

Causes of dynamic loading can include anything from people moving around to wind blowing against a structure, or objects being vibrated by an earthquake.


Loads are forces that are applied to structures and can be either static or dynamic. Where static loads only move very slowly, if at all, in the case of dynamic loads the forces move more rapidly, exerting a greater level of load stress on the structure or item.

Load stresses can lead to deformation and displacement in a structure, or even to a complete failure and collapse. Structural engineers analyse the effects of loads on different structures and structural elements to make sure they can withstand them.

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