Two plates are connected by fillet welds of size 10 mm and subjected to tension, as shown in the figure. The thickness of each plate is 12 mm. The yield stress and the ultimate stress of steel under tension are 250 MPa and 410 MPa, respectively. The welding is done in the workshop (partial safety factor, 𝛾_𝑚𝑤 = 1.25). As per the Limit State Method of IS 800: 2007, what is the minimum length (in mm, rounded off to the nearest higher multiple of 5 mm) required of each weld to transmit a factored force P equal to 275 kN? 

Two bolted plates under tension with alternative arrangement of bolt holes are shown in figures $$1$$ and $$2.$$ The hole diameter, pitch, and gauge length are $$d, p$$ and $$g$$ respectively.

Which one of the following conditions must be ensured to have higher net tensile capacity of configuration shown in figure $$2$$ than that shown in figure $$1$$?

Two equal angles $$ISA$$ $$100\,\,mm \times 100\,\,mm$$ of thickness $$10$$ $$mm$$ are placed back-to-back and connected to the either side of a gusset plate through a single row of $$16$$ $$mm$$ diameter rivets in double shear. The effective areas of the connected and unconnected legs of each of these angles are $$775$$ $$m{m^2}$$ and $$950$$ $$m{m^2},$$ respectively. If these angles are NOT Tack riveted, the net effective area of this pair of angle is

A truss tie consisting of $$2$$ $$ISA$$ $$75 \times 75 \times 8\,\,mm$$ carries a pull of $$150$$ $$kN.$$ At ends the two angles are connected, one each on either side of a $$10$$ $$mm$$ thick gusset plate, by $$18$$ $$mm$$ diameter rivets arranged in one row. The allowable stresses in rivet are $${f_s} = 90.0\,\,N/m{m^2}$$ and $${f_{br}} = 250\,\,N/m{m^2}$$.

Minimum number of rivets required at each end is