GB/T 18258-2026 Damping materials—Testing method for damping properties English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 13.220.10
CCS H 57
National Standard of the People's Republic of China
GB/T 18258-2026
Replaces GB/T 18258-2000
Damping materials - Testing method for damping properties
阻尼材料 阻尼性能测试方法
Issue date: 2026-01-28 Implementation date: 2027-02-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms, Definitions, and Symbols
4 Test Method and Principle
5 Test Apparatus
6 Test Specimen
7 Test Procedure
8 Data Processing
9 Test Report
10 Precision
Test Method for Damping Properties of Damping Materials
1 Scope
This document describes the test method for determining vibration damping characteristics, including the loss factor η, elastic modulus E, and shear modulus G, of materials used in structural vibration, architectural acoustics, and noise and vibration control, within the frequency range of 50 Hz to 5000 Hz and the effective service temperature range of the material.
This document is applicable to materials such as metals, enamels, ceramics, rubbers, plastics, reinforced epoxy resin matrices, and wood that can be prepared into cantilever beam specimen structures.
2 Normative References
The following documents contain provisions which, through normative reference in this text, constitute essential provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 2298 Mechanical Vibration, Shock and Condition Monitoring — Vocabulary
GB/T 4472 Determination of Density and Relative Density for Chemical Products
GB/T 5163 Sintered Metal Materials (Excluding Hardmetals) — Determination of Density, Oil Content, and Open Porosity of Permeable Sintered Metal Materials
GB/T 14465 Terminology for Damping Properties of Materials
3 Terms, Definitions, and Symbols
3.1 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 2298 and GB/T 14465, and the following apply.
3.1.1
self-supporting damping materials
Damping materials that are relatively rigid and can be directly fabricated into specimens from the material itself without the need for other auxiliary materials to be clamped by the test apparatus for testing.
3.1.2
non-self-supporting damping materials
Damping materials that are relatively soft and cannot be directly fabricated into specimens from the material itself without the aid of other auxiliary materials to be clamped by the test apparatus for testing.
3.1.3
half-power bandwidth
The frequency difference on a resonance curve, on either side of the resonance peak, at which the amplitude is 0.707 times the resonance amplitude (i.e., 3 dB down).
3.1.4
"n dB" bandwidth
The frequency difference on a resonance curve, on either side of the resonance peak, at two non-resonant points where the resonance peak value is reduced by n dB.
NOTE: The value of n is chosen by the user, with an allowable range of 0.5 < n < 3.
3.1.5
free-layer (extensional) damper
A method for controlling structural vibration by bonding a layer of damping material onto the surface of a structure; energy is dissipated through the periodic tensile-compressive deformation of the damping material.
3.1.6
constrained-layer (shear) damper
A method for controlling structural vibration by bonding a layer of damping material between the structural surface and an additional elastic layer (the constraining layer); the stiffness of the constraining layer is greater than that of the damping material, and energy is dissipated through the periodic deformation (primarily shear deformation) of the damping material.
3.2 Symbols
The following symbols apply to this document.
Cₙ — n-th mode coefficient for a homogeneous beam (C₁ = 0.55959, C₂ = 3.5069, C₃ = 9.8194, C₄ = 19.242, C₅ = 31.809, Cₙ = (π/2)(n - 0.5)² for n > 3)
D — ρ₁/ρ, density ratio, dimensionless
E — Elastic modulus of self-supporting damping material or homogeneous beam, in Pascals (Pa)
E₁ — Elastic modulus of non-self-supporting damping material, in Pascals (Pa)
f꜀ — c-th mode resonant frequency of the composite beam with damping material bonded on one side, in Hertz (Hz)
Δf꜀ — Half-power bandwidth of the c-th mode of the composite beam with damping material bonded on one side, in Hertz (Hz)
fₘ — m-th mode resonant frequency of the composite beam with damping material bonded on both sides, in Hertz (Hz)
Δfₘ — Half-power bandwidth of the m-th mode of the composite beam with damping material bonded on both sides, in Hertz (Hz)
fₙ — n-th mode resonant frequency of the base beam, in Hertz (Hz)
Δfₙ — Half-power bandwidth of the n-th mode, in Hertz (Hz)
fₛ — s-th mode resonant frequency of the composite beam with damping material sandwiched in the middle, in Hertz (Hz)
Δfₛ — Half-power bandwidth of the s-th mode of the composite beam with damping material sandwiched in the middle, in Hertz (Hz)
G₁ — Shear modulus of non-self-supporting damping material, in Pascals (Pa)
H — Thickness of the homogeneous beam (base beam), in meters (m)
H₁ — Thickness of the damping material, in meters (m)
l — Length of the beam, in meters (m)
M — E₁/E, modulus ratio, dimensionless
T — H₁/H, thickness ratio, dimensionless
η — Loss factor of self-supporting damping material or homogeneous beam, dimensionless
η꜀ — Δf꜀/f꜀, loss factor of the composite beam, dimensionless
ηₘ — Δfₘ/fₘ, loss factor of the composite beam with damping material bonded on both sides, dimensionless
ηₛ — Δfₛ/fₛ, loss factor of the sandwich specimen, dimensionless
η₁ — Loss factor of non-self-supporting damping material, dimensionless
n, c, m, s — Mode order: 1, 2, 3, …
ρ — Density of the beam, in kilograms per cubic meter (kg/m³)
ρ₁ — Density of the damping material, in kilograms per cubic meter (kg/m³)
4 Test Method and Principle
4.1 Overview of Test Method
4.1.1 Damping materials are classified into self-supporting damping materials and non-self-supporting damping materials. Different types of damping materials should use different specimens to determine their damping properties.
4.1.2 For testing the damping properties of self-supporting damping materials, specimens consisting of a single homogeneous beam made from the damping material itself are used to determine the elastic modulus E and loss factor η of the homogeneous beam.
4.1.3 The determination of the elastic damping properties of non-self-supporting damping materials involves two steps. First, a self-supporting homogeneous metal beam specimen (referred to as the base beam or bare beam) is tested to determine its resonant frequencies within the temperature range of interest. Then, the damping material is bonded to the base beam to form a composite beam specimen, either by bonding on one side or both sides. The resonant frequencies and the composite loss factor of the composite beam specimen within the relevant temperature range are tested. The damping characteristics calculated from the base beam specimen test are described in 8.2 a), and the calculation process for the material damping characteristics from the composite beam specimen test is described in 8.2 b) to d).
4.1.4 The procedure for testing the constrained-layer (shear) damping characteristics of non-self-supporting damping materials is similar to 4.1.3, except that two identical base beams are used to sandwich the damping material in the middle, forming a composite beam specimen structure for testing.
4.1.5 The data reduction for composite beam specimens with damping material bonded on one side and both sides uses simplifications based on classical beam theory. The analysis is based on the plane cross-section assumption and does not consider rotational inertia or shear deformation. The thickness of the damping material specimen should be less than 4 times the thickness of the metal beam but not less than the thickness of the metal beam (see 6.1.2).
4.1.6 For composite beam specimens with damping material sandwiched in the middle, when the modulus of the damping layer is more than 10 times lower than the modulus of the homogeneous beam, the equations for calculating the shear properties of the damping material do not include the extensional term for the damping layer.
4.1.7 The calculation and solution of the equations for damping characteristics using the sandwich beam specimen are based on a sinusoidal expansion of the mode shapes. For this composite beam specimen, calculations should preferably start from the second mode order. For other specimen configurations, results from the first mode order may be used.
Standard
GB/T 18258-2026 Damping materials—Testing method for damping properties (English Version)
Standard No.
GB/T 18258-2026
Status
to be valid
Language
English
File Format
PDF
Word Count
10500 words
Price(USD)
315.0
Implemented on
2026-8-1
Delivery
via email in 1~5 business day
Detail of GB/T 18258-2026
Standard No.
GB/T 18258-2026
English Name
Damping materials—Testing method for damping properties
GB/T 18258-2026 Damping materials—Testing method for damping properties English, Anglais, Englisch, Inglés, えいご
This is a draft translation for reference among interesting stakeholders. The finalized translation (passing through draft translation, self-check, revision and verification) will be delivered upon being ordered.
ICS 13.220.10
CCS H 57
National Standard of the People's Republic of China
GB/T 18258-2026
Replaces GB/T 18258-2000
Damping materials - Testing method for damping properties
阻尼材料 阻尼性能测试方法
Issue date: 2026-01-28 Implementation date: 2027-02-01
Issued by the General Administration of Quality Supervision, Inspection and Quarantine of the People's Republic of China
the Standardization Administration of the People's Republic of China
Contents
Foreword
1 Scope
2 Normative References
3 Terms, Definitions, and Symbols
4 Test Method and Principle
5 Test Apparatus
6 Test Specimen
7 Test Procedure
8 Data Processing
9 Test Report
10 Precision
Test Method for Damping Properties of Damping Materials
1 Scope
This document describes the test method for determining vibration damping characteristics, including the loss factor η, elastic modulus E, and shear modulus G, of materials used in structural vibration, architectural acoustics, and noise and vibration control, within the frequency range of 50 Hz to 5000 Hz and the effective service temperature range of the material.
This document is applicable to materials such as metals, enamels, ceramics, rubbers, plastics, reinforced epoxy resin matrices, and wood that can be prepared into cantilever beam specimen structures.
2 Normative References
The following documents contain provisions which, through normative reference in this text, constitute essential provisions of this document. For dated references, only the edition cited applies. For undated references, the latest edition (including any amendments) applies.
GB/T 2298 Mechanical Vibration, Shock and Condition Monitoring — Vocabulary
GB/T 4472 Determination of Density and Relative Density for Chemical Products
GB/T 5163 Sintered Metal Materials (Excluding Hardmetals) — Determination of Density, Oil Content, and Open Porosity of Permeable Sintered Metal Materials
GB/T 14465 Terminology for Damping Properties of Materials
3 Terms, Definitions, and Symbols
3.1 Terms and Definitions
For the purposes of this document, the terms and definitions given in GB/T 2298 and GB/T 14465, and the following apply.
3.1.1
self-supporting damping materials
Damping materials that are relatively rigid and can be directly fabricated into specimens from the material itself without the need for other auxiliary materials to be clamped by the test apparatus for testing.
3.1.2
non-self-supporting damping materials
Damping materials that are relatively soft and cannot be directly fabricated into specimens from the material itself without the aid of other auxiliary materials to be clamped by the test apparatus for testing.
3.1.3
half-power bandwidth
The frequency difference on a resonance curve, on either side of the resonance peak, at which the amplitude is 0.707 times the resonance amplitude (i.e., 3 dB down).
3.1.4
"n dB" bandwidth
The frequency difference on a resonance curve, on either side of the resonance peak, at two non-resonant points where the resonance peak value is reduced by n dB.
NOTE: The value of n is chosen by the user, with an allowable range of 0.5 < n < 3.
3.1.5
free-layer (extensional) damper
A method for controlling structural vibration by bonding a layer of damping material onto the surface of a structure; energy is dissipated through the periodic tensile-compressive deformation of the damping material.
3.1.6
constrained-layer (shear) damper
A method for controlling structural vibration by bonding a layer of damping material between the structural surface and an additional elastic layer (the constraining layer); the stiffness of the constraining layer is greater than that of the damping material, and energy is dissipated through the periodic deformation (primarily shear deformation) of the damping material.
3.2 Symbols
The following symbols apply to this document.
Cₙ — n-th mode coefficient for a homogeneous beam (C₁ = 0.55959, C₂ = 3.5069, C₃ = 9.8194, C₄ = 19.242, C₅ = 31.809, Cₙ = (π/2)(n - 0.5)² for n > 3)
D — ρ₁/ρ, density ratio, dimensionless
E — Elastic modulus of self-supporting damping material or homogeneous beam, in Pascals (Pa)
E₁ — Elastic modulus of non-self-supporting damping material, in Pascals (Pa)
f꜀ — c-th mode resonant frequency of the composite beam with damping material bonded on one side, in Hertz (Hz)
Δf꜀ — Half-power bandwidth of the c-th mode of the composite beam with damping material bonded on one side, in Hertz (Hz)
fₘ — m-th mode resonant frequency of the composite beam with damping material bonded on both sides, in Hertz (Hz)
Δfₘ — Half-power bandwidth of the m-th mode of the composite beam with damping material bonded on both sides, in Hertz (Hz)
fₙ — n-th mode resonant frequency of the base beam, in Hertz (Hz)
Δfₙ — Half-power bandwidth of the n-th mode, in Hertz (Hz)
fₛ — s-th mode resonant frequency of the composite beam with damping material sandwiched in the middle, in Hertz (Hz)
Δfₛ — Half-power bandwidth of the s-th mode of the composite beam with damping material sandwiched in the middle, in Hertz (Hz)
G₁ — Shear modulus of non-self-supporting damping material, in Pascals (Pa)
H — Thickness of the homogeneous beam (base beam), in meters (m)
H₁ — Thickness of the damping material, in meters (m)
l — Length of the beam, in meters (m)
M — E₁/E, modulus ratio, dimensionless
T — H₁/H, thickness ratio, dimensionless
η — Loss factor of self-supporting damping material or homogeneous beam, dimensionless
η꜀ — Δf꜀/f꜀, loss factor of the composite beam, dimensionless
ηₘ — Δfₘ/fₘ, loss factor of the composite beam with damping material bonded on both sides, dimensionless
ηₛ — Δfₛ/fₛ, loss factor of the sandwich specimen, dimensionless
η₁ — Loss factor of non-self-supporting damping material, dimensionless
n, c, m, s — Mode order: 1, 2, 3, …
ρ — Density of the beam, in kilograms per cubic meter (kg/m³)
ρ₁ — Density of the damping material, in kilograms per cubic meter (kg/m³)
4 Test Method and Principle
4.1 Overview of Test Method
4.1.1 Damping materials are classified into self-supporting damping materials and non-self-supporting damping materials. Different types of damping materials should use different specimens to determine their damping properties.
4.1.2 For testing the damping properties of self-supporting damping materials, specimens consisting of a single homogeneous beam made from the damping material itself are used to determine the elastic modulus E and loss factor η of the homogeneous beam.
4.1.3 The determination of the elastic damping properties of non-self-supporting damping materials involves two steps. First, a self-supporting homogeneous metal beam specimen (referred to as the base beam or bare beam) is tested to determine its resonant frequencies within the temperature range of interest. Then, the damping material is bonded to the base beam to form a composite beam specimen, either by bonding on one side or both sides. The resonant frequencies and the composite loss factor of the composite beam specimen within the relevant temperature range are tested. The damping characteristics calculated from the base beam specimen test are described in 8.2 a), and the calculation process for the material damping characteristics from the composite beam specimen test is described in 8.2 b) to d).
4.1.4 The procedure for testing the constrained-layer (shear) damping characteristics of non-self-supporting damping materials is similar to 4.1.3, except that two identical base beams are used to sandwich the damping material in the middle, forming a composite beam specimen structure for testing.
4.1.5 The data reduction for composite beam specimens with damping material bonded on one side and both sides uses simplifications based on classical beam theory. The analysis is based on the plane cross-section assumption and does not consider rotational inertia or shear deformation. The thickness of the damping material specimen should be less than 4 times the thickness of the metal beam but not less than the thickness of the metal beam (see 6.1.2).
4.1.6 For composite beam specimens with damping material sandwiched in the middle, when the modulus of the damping layer is more than 10 times lower than the modulus of the homogeneous beam, the equations for calculating the shear properties of the damping material do not include the extensional term for the damping layer.
4.1.7 The calculation and solution of the equations for damping characteristics using the sandwich beam specimen are based on a sinusoidal expansion of the mode shapes. For this composite beam specimen, calculations should preferably start from the second mode order. For other specimen configurations, results from the first mode order may be used.
