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بسم الله الرحمن الرحيم. َََ وَ حَمَلْنَهُ عَلَىَ ذَاتِ َألوَْاٍٍٍٍح َودُسُرٍ َ تجْرِي بِأَعْيُنِنَا َجَََزاءً ِلمَن كَانَ كُفِِرَ. القمر 13-14. STRUCTURAL JOINTS. IN. POLYMERIC COMPOSITE MATERIALS. By Hossam Sallam, Ph.D. Zagazig University. Objectives.
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بسم الله الرحمن الرحيم َََ وَ حَمَلْنَهُ عَلَىَ ذَاتِ َألوَْاٍٍٍٍح َودُسُرٍ َ تجْرِي بِأَعْيُنِنَا َجَََزاءً ِلمَن كَانَكُفِِرَ القمر 13-14
STRUCTURAL JOINTS IN POLYMERIC COMPOSITE MATERIALS By Hossam Sallam, Ph.D. Zagazig University
Objectives The main goal of this review article is to present a sound background regarding the development of the understanding of the mechanical behavior and the failure modes of the mechanically fastened, snap, bonded, andhybridjoints in polymeric composite materials.
LAYOUT • INTRODUCTION JOINTS ------ COMPOSITES • MECHANICALLY FASTENED JOINTS Kt ------ FAILURE MODES • SNAP JOINTS • BONDED JOINTS Fusion Bonding for Joining Thermoplastic Matrix Composites ADHESIVE BONDED SIMILAR/DISSIMILAR MATERIALS. • HYBRID JOINTS
Introduction STRUCTURAL JOINTS
Introduction COMPOSITE MATERIALS Classification Of Composite Materials W.R.T Reinforcement Forms W.R.T Type of Matrix • Particle • Polymers • Metals • Fiber Discontinuous • Ceramics Continuous • Laminate
out line • INTRODUCTION • MECHANICALLY FASTENED JOINTS • SNAP JOINTS • BONDED JOINTS • HYBRID JOINTS • CONCLOUSIONS
MECHANICALLY FASTENED JOINTS Single lap bolted joint Double Strap bolted joint
Tab Tab Load Cell Rigid Washer Strain Gauge Washer D Load Cell Dw Nut Washer Bolt W Specimen W (b) (a) (c) Types of Circular Hole in Tensioned FRP Plates • OPEN-HOLE TENSION • FILLED-HOLE TENSION WITH/WITHOUT A CLAMP-UP LOAD. • BOLTED JOINT, BOLT-LOADED HOLE WITH/WITHOUT CLAMP-UP LOAD.
FAILURE MODESOF TENSION PLATES OPEN-HOLE Fiber Breakage Matrix Cracking Delamination Fiber-MatrixSplitting
e P P P PَSO=fult [0.6(e-dH/2)2t] CAN PَSO=fult(et)/1.2 Euro PَSO= fult(et) USA P P FAILURE MODESOF BOLTED JOINTS sf/sَo= 0.8 Steel sf/sَo< 0.5 FRP Net-Tension sَN= P /([W-dH]t) Shear-Out sَSO= PSO/(2et) Transverse splitting Cleavage Bearing Pull-out sَb= P /(dBt)
out line • INTRODUCTION • MECHANICALLY FASTENED JOINTS • SNAP JOINTS • BONDED JOINTS • HYBRID JOINTS • CONCLOUSIONS
SNAP JOINTS (a) CompositeTransmissionTower(b) Truss Joint
out line • INTRODUCTION • MECHANICALLY FASTENED JOINTS • SNAP JOINTS • BONDED JOINTS • HYBRID JOINTS • CONCLOUSIONS
Fusion Bonding Techniques Bulk Heating Frictional Heating Electromagnetic Heating Two-stage Techniques Induction Welding Microwave Heating Dielectric Heating Resistance Welding Hot Plate Welding Hot Gas Welding Radiant Welding Co-consolidation Hot-melt Adhesives Dual Resin Bonding Spin Welding Vibration Welding Ultrasonic Welding Infrared Welding Focused Infrared Welding Laser Welding Solar Energy
BONDED JOINTS ADHESIVE-1 • Single lap • Double lap • Double strap
BONDED JOINTS ADHESIVE-2 Stepped lap Doublestepped lap Single scarf Double scarf
BONDED JOINTS A A ADHESIVE-3 AL–6XN steel T700 carbon/epoxy The general geometric parameters for a tongue-and-groove joint. New design with flat, pointed inserts Wavy-lap joint main dimensions
Peel action Peeling Prevention of failure in Adhesive Joints Bead end (if possible) Increase area Increase stiffness Rivet, bolt or spot weld
out line • INTRODUCTION • MECHANICALLY FASTENED JOINTS • SNAP JOINTS • BONDED JOINTS • HYBRID JOINTS • CONCLOUSIONS
HYBRID JOINTS Retrofitting schemes
out line • INTRODUCTION • MECHANICALLY FASTENED JOINTS • BONDED JOINTS • SNAP JOINTS • HYBRID JOINTS • CONCLOUSIONS
CONCLUSIONS • All joining methods present advantages and drawbacks, and they may be more or less suitable to particular application depending on its specific requirements. • Well-established joining technologies for metallic structures are not directly applicable to FRP. • Some adhesives are disposed to degradation by temperature and humidity. • Hybrid joints give better static as well as fatigue performance than adhesive joints in composites.
الحمد لله رب العالمين وشكراَ