# Blog

## What is lumped mass structural dynamics? A lumped mass is a load that can be applied to a node in a static stress, natural frequency (modal) or modal superposition analysis. A lumped mass can be used to resist the translation or rotation of a node.

## What is lumped mass matrix?

We have considered mass of the element as uniformly distributed throughout the element. ... Hence, these mass matrices are called as consistent matrices. We distribute the complete mass of the element at the two nodes. The mass matrix formed in this way is called as lumped mass matrix.

## What is the difference between consistent mass and lumped mass?

If the mass of the beam is assumed to be concentrated at two known points ( supports ) such a system is called as Lumped mass. On the other hand when the entire mass of system is evenly distributed over it's length it is known as consistent mass.

## What is lumped mass idealization?

Lumped mass idealization is used to discretize the original beam structure with distributed mass to a weightless beam with distributed masses substituted with lumped masses at different nodal points. A numerical example obtained from literature is given to illustrate the application of the present model.

## Which of the following is property of global stiffness matrix?

Diagonal terms of the matrix are always positive i.e. force directed in say left direction cannot produce a displacement in right direction. Diagonal terms will be zero or negative only if the structure is unstable.Jan 6, 2020

## When the complete mass of the element is distributed equally at the two nodes of a element then mass matrices What are they known as?

Mass matrix computed by considering mass to be distributed equally at the two nodes of the element is known as lumped mass matrix.

## What is Sdof in earthquake?

... a semi-active, single degree-of-freedom (SDOF), controlled system subjected to an earthquake ground motion with a control force applied to the first mass, as illustrated in Figure 1.

## What is meant by structural dynamics?

Structural dynamics is a type of structural analysis which covers the behavior of a structure subjected to dynamic (actions having high acceleration) loading. Dynamic loads include people, wind, waves, traffic, earthquakes, and blasts.

## What is time period of a building?

Natural Period Tn of a building is the time taken by it to undergo one complete cycle of oscillation. It is an inherent property of a building controlled by its mass m and stiffness k. ... (with smaller stiffness k) have larger natural period than light and stiff buildings.

## What is lumped mass in physics?

• Answer Wiki. Lumped mass just means that you assume all the mass is concentrated in one rigid object. This means only the blocks have considered mass...the springs are assumed mass less.instead of continuous mass of a coiled wire as it really is.  ### What is a lumped model in Mechanical Engineering?

• Such circuit or lumped models can be easily coupled with standard finite element (FE) models, which is useful when simulating complex mechanical systems. In general, all of the components of a mechanical system can essentially be modeled as a combination of lumped mass, stiffness, and damping parameters.

### What is a lumped system?

• A lumped system is a system who's components can be treated as independent, zero-dimensional "blocks". The classic example is "lumped model" in electronics: capacitors, inductors and resistors are "lumped" as they have values the are independent of each other and they have no physical dimensional dependency

### What is lumped mass model of multi-DOF system?

• The method of lumped mass is adopted to found purely rotational dynamic model of multi-DOF system for double-helical planetary gear sets. The dynamic response between teeth of the system is carried out by the method of the 4–steps Runge-Kutta.