登录

The dynamic modulus of elasticity assesses how a concrete structure deforms under impact or dynamic loads. It is typically higher than the static modulus of elasticity, measured under slow, steady loading conditions.

The sonic test is a common method to determine the dynamic modulus. In this test, a concrete beam, sized either 6 x 6 x 30 inches or 4 x4 x20 inches, is clamped at its center. Vibrations are initiated at one end of the beam by an electromagnetic exciter unit powered by a variable-frequency oscillator. A pick-up device at the other end detects these vibrations, which are then amplified and measured using an indicator.

The vibrations at varying frequencies are transmitted through the specimen till it starts to resonate at its fundamental frequency. The dynamic modulus of elasticity (Ed) in pounds per inch is computed mathematically by substituting the beam's fundamental frequency (n) in Hertz, length (L) in inches and density (⍴) in pounds per cubic feet.

Eq1

Another method to estimate the dynamic modulus involves the stress-strain curve of concrete. By drawing a tangent at the curve's origin and calculating its slope, the initial tangent modulus is determined. This value is approximately equal to the dynamic modulus of elasticity.

Figure 1

来自章节 10:

article

Now Playing

10.2 : Dynamic Modulus of Elasticity of Concrete

Elasticity, Creep, and Shrinkage in Concrete

171 Views

article

10.1 : Elasticity in Concrete

Elasticity, Creep, and Shrinkage in Concrete

56 Views

article

10.3 : Creep in Concrete

Elasticity, Creep, and Shrinkage in Concrete

73 Views

article

10.4 : Factors Affecting Creep

Elasticity, Creep, and Shrinkage in Concrete

80 Views

article

10.5 : Effects of Creep

Elasticity, Creep, and Shrinkage in Concrete

60 Views

article

10.6 : Shrinkage in Concrete

Elasticity, Creep, and Shrinkage in Concrete

46 Views

article

10.7 : Drying Shrinkage

Elasticity, Creep, and Shrinkage in Concrete

45 Views

article

10.8 : Carbonation Shrinkage

Elasticity, Creep, and Shrinkage in Concrete

85 Views

article

10.9 : Types of Non-structural Cracks in Concrete

Elasticity, Creep, and Shrinkage in Concrete

83 Views

article

10.10 : Mass Concreting

Elasticity, Creep, and Shrinkage in Concrete

35 Views

article

10.11 : Hot Weather Concreting

Elasticity, Creep, and Shrinkage in Concrete

41 Views

article

10.12 : Cold Weather Concreting

Elasticity, Creep, and Shrinkage in Concrete

33 Views

JoVE Logo

政策

使用条款

隐私

科研

教育

关于 JoVE

版权所属 © 2025 MyJoVE 公司版权所有,本公司不涉及任何医疗业务和医疗服务。