STOCHASTIC SECTION MODULUS REQUIREMENT FOR CARBON FIBRE REINFORCED PLASTIC PULTRUDED BEAMS

Thesis Abstract

Six Carbon Fibre Reinforced Plastic (CFRP) pultruded beam section from The Pultex® Pultrusion Design Manual Volume 4 – Revision 8 Copyright © 2004 by Creative Pultrusions Inc., were assumed to be simply supported doubly symmetric I-section, with uniformly distributed load of 3.5kN/m2 applied over the length of 3.050m each. A comparative analysis of section modulus effect under the load and resistance factor design (LRFD) and allowable stress design (ASD) was considered based on computer program using FORM5 and ABAQUS 6.10 CAE that was used to generate results for reliability and finite element analysis respectively. Safety indices generated for reliability analysis from FORM5 based on load and resistance factor design (LRFD) and allowable stress design (ASD) format by varying load ratio and section modulus was analyzed. The general conclusion from the results are that, the safety of all the beam section increased with increase in section modulus by average of 1.1% for both load and resistance factor design (LRFD) and allowable stress design (ASD) format. The implication of this is that, when the load and resistance factor design (LRFD) and allowable stress design (ASD) design format is employed, the reserved elastic moment of the carbon fibre reinforced plastic (CFRP) beams are fully utilized, with the possibility of the beam reaching its full elastic moment at higher loading, hence section modulus can be reduced, that would result in lower beam section. Also for finite element analysis (FEA) considered using ABAQUS 6.10 CAE in which the stresses, displacement, strain on the carbon fibre reinforced plastic (CFRP) pultruded beams obtained are analyzed and graphically presented and based on the design parameters, the deformation and the Von Mises stress distribution obtained indicates that, the field of high stress is only shown in Model 1 with 661.2N/mm2 which is minimal under the said load when compared to bending and tensile strength of 3300N/mm2 for carbon fibre reinforced plastic (CFRP).