KSME Journal

, Volume 10, Issue 1, pp 49–56 | Cite as

Ultimate strength prediction of continuous fiber-reinforced brittle matrix composites

  • Chongdu Cho


A model to predict ultimate strength of continuous fiber-reinforced brittle matirix composites has been developed. A statistical theory for the strength of the uniaxially fiber-reinforced brittle matrix composite is presented. Material of matrix is assumed to be homogeneous and isotropic, so that the strength of material is anywhere constant, whilst that of fiber is considered to show Weibull statistical distribution. The theory may be utilized to optimize the biaxial and multidirectional tensile strength properties of laminated materials. The composite strength is estimated by assuming no interacting matrix cracks. The frictional shear stress caused by bridging fibers is involved in the strength computation. The predicted strength is compared to experimental results with LAS-Glass/Nicalon fiber composite.

Key Words

Brittle Matrix Composite Weibull Statistics Tensile Strength Interfacial Friction Fibers 



Fiber diameter


Elastic modulus

\(G_{\delta z_i } \left( {\sigma _i } \right)\)

Probability that the element δZ i fractures subjected to the stress less than σ i


Fiber specimen length


Average fracture distance


Slip zone length


Weibull modulus


Probability of failure


Strength scaling parameter; fiber mean strength (m=∞)


Volume fraction


Dimension factor


Normalizing parameter


Parameter defined by 4τ/d f


Normal stress


Fiber specimen failure stress


Fiber stress at a distancez i


Ultimate strength


Interfacial shear stress


Parameter defined by σ m /S 0









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Copyright information

© The Korean Society of Mechanical Engineers (KSME) 1996

Authors and Affiliations

  • Chongdu Cho
    • 1
  1. 1.iASMELab, Department of Mechanical EngineeringInha UniversityInchonKorea

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