The

**neutral axis**is an**axis**in the cross section of a beam (a member resisting bending) or shaft along which there are no longitudinal stresses or strains. If the section is symmetric, isotropic and is not curved before a bend occurs, then the**neutral axis**is at the geometric centroid.Then, what is meant by plastic moment?

In structural engineering, the

**plastic moment**(Mp) is a property of a structural section. It is defined as the**moment**at which the entire cross section has reached its yield stress. In practice most materials are work-hardened resulting in increased stiffness and**moment**resistance until the material fails.What is the plastic bending?

**Plastic bending**is a nonlinear behavior particular to members made of ductile materials that frequently achieve. much greater ultimate

**bending**strength than indicated by a linear elastic

**bending**analysis.

1

## Why shear stress is maximum at neutral axis?

The vertical

**shear**force creates horizontal**shear stress**. At**neutral axis**we will have more fibers at top and bottom to**shear**. That is the reason**shear stress**is not**maximum at neutral axis**for triangular section, it is**maximum**at h/2.2

## What is the neutral plane?

In mechanics, the

**neutral plane**or**neutral**surface is a conceptual**plane**within a beam or cantilever. When loaded by a bending force, the beam bends so that the inner surface is in compression and the outer surface is in tension. This is the**neutral plane**.3

## What is the principal axis?

a line passing through the center of the surface of a lens or spherical mirror and through the centers of curvature of all segments of the lens or mirror.

**Physics**. one of three mutually perpendicular**axes**of a body about which the moment of inertia is maximum or minimum.4

## What do you mean by curved beams?

**Curved Beam**. (in strength of materials and the theory of elasticity), a body whose geometric shape is formed by the motion in space of a plane figure (called the cross section of the

**curved beam**); its center of gravity always follows a certain curve (the axis), and the plane of the figure is normal to the curve.

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## What is elastic section modulus?

The

**elastic section modulus**is defined as S = I / y, where I is the second moment of area (or moment of inertia) and y is the distance from the neutral axis to any given fibre. It is often reported using y = c, where c is the distance from the neutral axis to the most extreme fibre, as seen in the table below.6

## What is meant by plane of bending?

The beam is initially straight with a cross section that is constant throughout the beam length. The beam has an axis of symmetry in the

**plane**of**bending**. The proportions of the beam are such that it would fail by**bending**rather than by crushing, wrinkling or sideways buckling.7

## Where is shear stress maximum?

When an section beam is subjected to both Bending and

**Shear Stresses**it is normal to find that the**Maximum**Principle**Stress**is at the top of the Web. The other possible value is the**Maximum**Bending**Stress**which occurs at the outer edge of the Flange.8

## What is meant by pure bending?

**Pure bending**is a condition of stress where a

**bending**moment is applied to a beam without the simultaneous presence of axial, shear, or torsional forces.

**Pure bending**occurs only under a constant

**bending**moment (M) since the shear force (V), which is equal to , has to be equal to zero.

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## What is meant by shear center?

**Shear Center**is a point through which if the external load passes, then there will not be any twisting of the section. In other words, section will only be subjected to bending. It won't be subjected to Torsion. ( Torsion due to Load being applied at a distance eccentric to the

**shear center**)

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## What is the meaning of longitudinal stress?

**Longitudinal stress**is the

**stress**in a pipe wall, acting along the

**longitudinal**axis of the pipe. And it is produced by the pressure of the fluid in the pipe. It is also called as Hoop

**stress**. Radial

**stress**is

**stress**towards or away from the central axis of a component.

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## What do you mean by bending stress?

**Bending stress**is a more specific type of normal

**stress**. When a beam experiences load like that shown in figure one the top fibers of the beam undergo a normal compressive

**stress**. The

**stress**at the horizontal plane of the neutral is zero. The bottom fibers of the beam undergo a normal tensile

**stress**.

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## What do you mean by Moment of resistance?

Definition : The

**moment of resistance**of the concrete section is the**moment**of couple formed by the total tensile force (T) in the steel acting at the centre of gravity of reinforcement and the total compressive force (C) in the concrete acting at the centre of gravity (c.g.) of the compressive stress diagram.13

## What is the polar moment of inertia?

**Polar moment of inertia**.

**Polar moment of inertia**is a quantity used to predict an object's ability to resist torsion, in objects (or segments of objects) with an invariant circular cross section and no significant warping or out-of-plane deformation.

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## What is the unit of moment of inertia?

The amount of torque needed to cause any given angular acceleration (the rate of change in angular velocity) is proportional to the moment of inertia of the body. Moment of inertia may be expressed in units of

**kilogram meter**squared (**kg**. m^{2}) in**SI units**and pound-foot-**second**squared (lb.15

## What is the second moment of inertia?

The

**2nd moment**of area, also known as**moment of inertia**of plane area, area**moment of inertia**, or**second**area**moment**, is a geometrical property of an area which reflects how its points are distributed with regard to an arbitrary axis.16

## What is Ixx and Iyy?

Moment of inertia is the rotational analogue to mass. The moment of inertia must be specified with respect to a chosen axis of rotation. The symbols

**Ixx**,**Iyy**and Izz are frequently used to express the moments of inertia of a 3D rigid body about its three axis.17

## What is inertia moment?

**Moment**of

**inertia**is defined with respect to a specific rotation axis. The

**moment**of

**inertia**of a point mass with respect to an axis is defined as the product of the mass times the distance from the axis squared. The

**moment**of

**inertia**of any extended object is built up from that basic definition.

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## What is inertia in motion?

**Inertia**is the resistance of any physical object to any change in its position and state of motion. This includes changes to the object's speed, direction, or state of rest.

**Inertia**is also defined as the tendency of objects to keep moving in a straight line at a constant velocity.

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## Is inertia is a force?

**Inertia**is a

**force**which keeps stationary objects at rest and moving objects in motion at constant velocity.

**Inertia**is a

**force**which brings all objects to a rest position. A more massive object has more

**inertia**than a less massive object.

**Inertia**is the tendency of all objects to resist motion and ultimately stop.