وَ حَمَلْنَهُ عَلَىَ ذَاتِ َألوَْاٍٍٍٍح َودُسُرٍ َ بسم الله الرحمن الرحيم َََ وَ حَمَلْنَهُ عَلَىَ ذَاتِ َألوَْاٍٍٍٍح َودُسُرٍ َ تجْرِي بِأَعْيُنِنَا َجَََزاءً ِلمَن كَانَكُفِِرَ القمر 13-14

POLYMERIC COMPOSITE MATERIALS 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, and hybrid joints 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 Classification Of Composite Materials W.R.T W.R.T Reinforcement Forms W.R.T Type of Matrix Particle Polymers Fiber Metals 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

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. D W Tab (a) (b) Dw W Load Cell Rigid Washer Nut Bolt Tab Washer Strain Gauge Load Cell Specimen (c)

FAILURE MODES OF OPEN-HOLE TENSION PLATES Fiber Breakage Matrix Cracking Delamination Fiber-Matrix Splitting

FAILURE MODES OF BOLTED JOINTS e sَSO = PSO /(2et) sf/ sَo = 0.8 Steel sf/ sَo < 0.5 FRP P Net-Tension sَN = P /([W-dH]t) P Shear-Out sَSO = PSO /(2et) P Transverse PَSO = fult (et) USA splitting Cleavage PَSO=fult (et)/1.2 Euro Bearing PَSO=fult [0.6(e-dH/2)2t] CAN Pull-out sَb = P /(dBt)

out line INTRODUCTION MECHANICALLY FASTENED JOINTS SNAP JOINTS BONDED JOINTS HYBRID JOINTS CONCLOUSIONS

SNAP JOINTS

SNAP JOINTS (a) Composite Transmission Tower (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 Co-consolidation Hot-melt Adhesives Dual Resin Bonding Spin Welding Vibration Welding Ultrasonic Welding Induction Welding Microwave Heating Dielectric Heating Resistance Welding Hot Plate Welding Hot Gas Welding Radiant 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 Double stepped lap Single scarf Double scarf

BONDED JOINTS Wavy-lap joint main dimensions 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

Prevention of failure in Adhesive Joints Peeling Peel action Increase area Bead end (if possible) 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