Question

A three hinged arch of span 20 m and rise 5 m is loaded as shown in fig. The horizontal thrust 'H' is (in tons)_________.

• A. 50

Answer 1

The correct option is A 50

$\sum F_y=0$

$V_A+V_B=100t$

$\sum M_A=0$

$5\times 10\times 5+50\times 15=V_B\times 20$

$V_B=50t$

$M_C=0\text{(right side)}$

$50\times 5+H\times 5=V_B\times 10$

$H\times 5=50\times 10-50\times 5$

$H=50t$