Civil Engineering - Strength of Materials - Discussion

Discussion Forum : Strength of Materials - Section 4 (Q.No. 15)
15.
A three hinged arch is loaded with an isolated load 1000 kg at a horizontal distance of 2.5 m from the crown, 1 m above the level of hinges at the supports 10 metres apart. The horizontal thrust is
1250 kg
125 kg
750 kg
2500 kg
2325 kg.
Answer: Option
Explanation:
No answer description is available. Let's discuss.
Discussion:
16 comments Page 1 of 2.

Shah Sawar said:   4 years ago
1st find the vertical forces at both ends. For that take moment about A ( left end). 1000 x 2.5 - By x 10 = 0.
By = 250 kg.

Now sum of all vertical forces = 1000 kg, we get Ay = 750 kg.
Now take section of the arch at crown where moment = 0 and consider left section.

750 x 5 - Ax * 1 - 1000 x 2.5 = 0. ( Ax is the horizontal force at hinge support A).

Ax = 1250 kg.

Engineer said:   2 years ago
W = 1000 kg convert this load into UDL of half span of the arch then UDL load,
w = 200 kg/m.

The horizontal thrust formula for half UDL of the arch is = wl * l/16h.

So, H = w(l*l)/16h
= 200 * 10/16 * 1
= 1250 kg.
(2)

Subhash chandra said:   5 years ago
W=1000 kg convert this load into UDL of half span of the arch then UDL load,w=200 kg/m
The horizontal thrust formula for half UDL of the arch is =wl/16h.

So, H=wl/16h=200*10/16*1=1250 kg.
(2)

VIPIN SAINATH said:   5 years ago
The formula is H= W*X / 2h, Where X= L / sq.rt3, but X value is directly given in question, X=2.5m.

h=1m and Span is 10m.
H = (1000 kgx 2.5m)/ (2 x 1m) = 1250 kg.
(1)

Aryan said:   3 years ago
@All.

Here, it's not mentioned which side is the load is; Like they only told 2.5m from the crown.

Then, how to calculate further? Anyone explain me.

MANASWINI said:   9 years ago
Va = 750kg & Vb = 250kg.
Moment at crown due to external loading.
= Vb *l/2.
= 250 * 5.
= 1250kg m.
Horizontal thrust = 250/1=1250 kg.

Achut Paudel said:   10 years ago
@Tej Deuba,

This formula is for UDL. For a concentrated load, formula should be different.

Kisore said:   5 years ago
I got 2250kg of horizontal thrust by solving equilibrium method as we did for beams.

Tej deuba said:   1 decade ago
H = wl2/8h this formula is not apply when apply H = 781kg why answer is 1250kg.

GAURAB said:   6 years ago
It's WL/4H.
W=1000KG.
L= CENTER TO CENTER=5.
H= RISE =1.
SOLVE IT =1250KG.


Post your comments here:

Your comments will be displayed after verification.