## Stiffness |

**Stiffness** is the extent to which an object resists ^{[1]}

The complementary concept is **flexibility** or pliability: the more flexible an object is, the less stiff it is.^{[2]}

The stiffness, *k*, of a body is a measure of the resistance offered by an elastic body to deformation. For an elastic body with a single

where,

*F*is the force on the body- is the
displacement produced by the force along the same degree of freedom (for instance, the change in length of a stretched spring)

In the

Generally speaking, **influence coefficient** is sometimes used to refer to the coupling stiffness.

It is noted that for a body with multiple DOF, the equation above generally does not apply since the applied force generates not only the deflection along its own direction (or degree of freedom) but also those along with other directions.

For a body with multiple DOF, in order to calculate a particular direct-related stiffness (the diagonal terms), the corresponding DOF is left free while the remaining should be constrained. Under such a condition, the above equation can be used to obtain the direct-related stiffness for the degree of freedom which is unconstrained. The ratios between the reaction forces (or moments) and the produced deflection are the coupling stiffnesses.

A description including all possible stretch and shear parameters is given by the

Other Languages

العربية: جساءة

asturianu: Rixidez

azərbaycanca: Sərtlik

български: Коравина

bosanski: Krutost

català: Rigidesa

čeština: Tuhost

dansk: Stivhed

Deutsch: Steifigkeit

eesti: Jäikus

español: Rigidez

Esperanto: Rigideco

فارسی: سفتی

français: Raideur (mécanique)

한국어: 강성

հայերեն: Կոշտություն

hrvatski: Krutost

Ido: Rigideso

italiano: Rigidezza

македонски: Крутост

Bahasa Melayu: Kekakuan

Nederlands: Stijfheid

日本語: 剛性

polski: Sztywność

português: Rigidez

română: Rigiditate

русский: Жёсткость

slovenčina: Tuhosť

srpskohrvatski / српскохрватски: Krutost

தமிழ்: விறைப்பு

українська: Механічна жорсткість

Winaray: Pagkamatikig

中文: 剛度