Chapter 5- explosion in new york

Question 1

On reading the events that preceded the failure of hydropneumatic tank No. 2 and the explosion that followed the gas mains rupture what is a second lesson to be learnt from this case study

Answer 1

1. the hydropneumatic tank needs to be designed in accordance with legislations with correct safety features
   and that all modifications should be completed the same day so pressure does not build up.

Question 2

What mathematical deduction did Weidlinger Associates base their brief on and what did their nonlinear analysis show to make the legal case tight

Answer 2

relates to its shape of tank to the pressure which creates a non-linear relationship.
the buckling pressure was tested to be much higher than 0.48n/mm2, which is the pressure it was designed for. the pressure was even higher than 0.76n/mm2 which is the value that the pressure relief was illegally set too. but the pressure was lower than 0.9 which is the maxium discharge pressure of the pump.
the safety coefficient of steel is 1.67
the ultimate pressure is 1.67x0.48 = 0.8 > 0.76 proving that the pressure was too high and snapped the tank