This question was previously asked in

CGPSC Civil Official Paper 3 (Held on Feb 2018 - Shift 2)

Option 1 : \(\dfrac{d}{t_w}> 67 \varepsilon\)

ST 1: Reasoning & Mental Ability

6964

15 Questions
15 Marks
15 Mins

**Explanation**

Transverse Stiffeners are provided to increase buckling resistance of the web due to inclined compressive stress due to shear, It is provided vertically along the span.

Horizontal Stiffener / Longitudinal Stiffener is designed to prevent web buckling due to bending compression.

Both traverse and longitudinal stiffeners are provided to check the web buckling.

End Bearing Stiffeners are provided at the supports & Load Bearing Stiffeners are provided at the points of concentrated loads.

As per **IS 800** resistance to **shear buckling must be verified** when

Resistance to shear buckling shall be verified as specified, when

**\(\frac{d}{{{t_W}}}\) > 67 ϵ **for a web without stiffeners, and

> 67ϵ √ (Kv/5.35) for a web with stiffeners

Kv = Shear bucling coefficient

**Reference:**

https://2cl405uvd.files.wordpress.com/2015/06/800-2007.pdf

(Page: 65)

__Important Points__

if \(\frac{d}{{{t_W}}}\)< 67ϵ ⇒ unstiffened girder can be designed i.e. No girder required.

If 85 ϵ < \(\frac{d}{{{t_W}}}\)< 200 ϵ ⇒ Vertical stiffener (C1 and C2) may be provided.

If 200 ϵ < \(\frac{d}{{{t_W}}}\) < 250 ϵ ⇒ Vertical stiffener along with longitudinal stiffener at 0.2 d may be provided.

If 250 ϵ < \(\frac{d}{{{t_W}}}\) < 345 ϵ ⇒ Vertical stiffeners along with two longitudinal stiffeners at 0.2 d and 0.5 d respectively may be provided.