.

.7)

r

4⋅103 Rcmp

94

5.2. Concrete deformations at long-term load. Creep

Relationship between loading and deformations in concrete changes with

time the concrete is stressed. Deformation of concrete caused by long time loading is called creep.

There is a number of hypotheses which considering the mechanism of

creep deformations under action of the external loading.

σ

ε/σ

1

σ2

σ3

σ1>σ2>σ3

Age, days

Fig. 5.5. Relationship between time-dependent

deformation of creep of concrete (ε) and stresses (σ)

95

General deformation

Creep

on atim

foreD

Shrinkage

Elastic

deformation

Age of loading

Fig. 5.6. Kinds of time-dependent deformations of

concrete at action of continuous loading

96

Some calculating formulas for determination of creep (C (28))

m

of normal-weight concrete (age of loading 28 days)

Formula

Author

К

С

=