rivet bolt
DESCRIPTION
steelTRANSCRIPT
Slide 1
RIVETED AN BOLTED CONNECTIONS
Stress-Strain Curve for Mild Steel
SSC-Mild Steel
OAB - PROPORTIONAL. A - Limit of proportionality. B - Elastic limit.C,C - Upper and lower yield points.CD - Plastic Yield.DE - Strain hardening zone. E - Ultimate stress.EF - Ultimate strength. F - Breaking stress.
Classification of cross-sectionsPlastic (Class 1) Plastic hinges, plastic mechanismConsiderable ductilityIntermediate frames-plastic collapse mechanismStress distribution- rectangularCompact (Class 2) Develop plastic MR, inadequate plastic hinge rotation capacity for formation of plastic mechanism before bucklingFully plastic stress distribution inadequate ductilityAll structural elementsStress distribution- rectangularSemi-compact or Non-compact (Class 3) Extreme fiber in compression can reach yield stress, cannot develop plastic MR due to local bucklingYield stresses reach some parts of compression elementsplastic stress distribution partly possibleSections used in elastic designStress distribution- triangularSlender (Class 4)
Local buckling before attaining yield stress
Used in cold-formed membersLimit StatesLimit state of strength Loss of equilibrium and stability. Excessive deformation , fatigue, brittle facture, stress concentration. Limit state of serviceabilityDeformationsVibrations in structureCorrosionFire
Design for economySimplicityMinimum member of elements in the connectionReducing the number of members meeting at the connections
Partial Safety factors
Load (Qd) = f * Qc f partial safety factor acc to Table 4 of IS:800-2007
Strength factor m = Su / sd m partial safety factor acc to Table 5 of IS:800-2007
TYPES OF CONNECTIONS
RIVETED CONNECTIONS
L11 Bolt Connection.pdf
L11 Bolt Connection.pdf
BOLTED CONNECTIONS
L11 Bolt Connection.pdfAdvantagesSpeedy constructionLess skilled personsLess over all construction compared with riveted connections
DisadvantagesLoss in tensile strength- reduced thread area and stress concentrationVibrations make bolts loose
Classification of bolted connectionsBased on forceResultant force transferConcentric connectionsEx-tension and compression membersEccentric connectionsEx-bracket connectionsSubjected to momentsEx-beam columns in framed structures
Based on type of force
Shear connections- load transfer through shear- ex lap, butt jointTension connections- load transfer through tension on bolts- ex hanger connectionsCombined Shear+Tension connections- ex bracings
Based on force mechanismBearing type- bolts bear against holes to transfer force.Ex-slip type connectionsFriction type- transfer of force by friction between plates.Ex-slip critical connections
Types of BoltsUnfinished ( Black)boltsFinished (Turned) boltsHigh strength friction grip (HSFG) bolts
Types of bolted jointsLap jointButt joint
Failures in bolted jointsShear failure of boltsBearing failure of boltsBearing failure of platesTension failure of boltsTension or tearing failure of platesBlock shear failure
AECT250-Lecture 12.pdf
Prying forces
Pitch, Edge DistanceTHANK YOU