What is Rivet Value? and Efficiency of a rivet joint:-

It is defined as the maximum safe force one rivet can withstand. The strength of a rivet in shearing and bearing is calculated and the lesser value is taken as Rivet value. Beyond this value, the rivet will either fail in shear or will be crushed in bearing. the value of shearing and bearing strength one rivet can be calculated from the following relations:-

Note:- Rivet value is least of the equations (i) and (ii)

The original strength of a structural sheet section is reduced by rivet holes provided in it. The efficiency of a rivet joint is the ratio of the strength of riveted joint to the strength of the solid plate(Ex. strength of solid plate without rivet hole). It is denoted by ɳ and is expressed as percentage. The effectiveness of a particular riveted joint is measured by the efficiency. Mathematically efficiency is expressed as:
                                                            ɳ = Strength of joint / Strength of solid plate *100
Where, strength of the riveted joint = Least of Pb, Pt and Ps
Strength of solid plate may be defined as resistance offered by the plate against tearing.
Tearing strength of plate is expressed as ൳at * (p-d)*t
As there is no rivet hole, therefore the value of d = 0
so, Mathematically,     Strength of Solid Plate = ൳at * p * t
Maximum efficiency can be achieved when the number of holes are minimum at the critical(weakest) section.
                                                 ɳ max = (p-d / p) *100
where, p = pitch of rivets
            d = gross diameter of rivet



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