Project 2- Warehouse Building located in Chennai and simply supported gantry girder to carry electric overhead travelling crane.

1. Design a Warehouse Building located in Chennai using STAAD Pro Connect Edition. The specification must be as follows:

Width	30m
Length	50m
Eave Height	9m
Bay spacing	6m
Soil type	Medium
Safe Bearing Capacity	200 kN/m2
Roof slope	1 in 12

Assume suitable sections for structural elements. Follow IS800:2007, IS1893 and IS 875

1. Prepare a Design Basis Report for the project
2. Create structural model using STAAD Pro Connect Edition
3. Prepare DL, LL, WL and EQL load calculations as per IS 875 standards
4. Design using MS – Excel
   1. Steel column
   2. Rafter
   3. Base plate
   4. Pedestal
   5. Z- purlin

1. Design Foundations using STAAD Foundation.
2. Attach necessary sketches and drawings wherever required.
3. All stipulations, assumptions and design parameter must adhere to Indian Standards.

Dead Load (DL):

Roof Dead Load:

Assuming a reinforced concrete roof with a thickness of 0.15m and a density of 25 kN/m³:

DL roof = thickness x density = 0.15m x 25 kN/m³ = 3.75 kN/m²

Floor Dead Load:

Assuming a reinforced concrete floor with a thickness of 0.15m and a density of 25 kN/m³:

DL floor = thickness x density = 0.15m x 25 kN/m³ = 3.75 kN/m²

Wall Dead Load:

Assuming a masonry wall with a thickness of 0.3m and a density of 20 kN/m³:

DL wall = thickness x density = 0.3m x 20 kN/m³ = 6 kN/m²

Total Dead Load:

DL total = DL roof + DL floor + DL wall = 3.75 kN/m² + 3.75 kN/m² + 6 kN/m² = 13.5 kN/m²

Live Load (LL):

Assuming an occupancy category of storage, with a live load of 5.0 kN/m²:

LL_total = 5.0 kN/m²

Earthquake Load (EQL):

Importance Factor (I):

Based on the occupancy category, the importance factor is 1.0 for storage.

Response Reduction Factor (R):

For Chennai, in seismic zone 3, the response reduction factor (R) is typically 5.0 as per IS 1893.

Zone Factor (Z):

For Chennai, in seismic zone 3, the zone factor (Z) is typically 0.16 as per IS 1893.

Design Horizontal Acceleration (Ah):

Ah = Z x g, where g is the acceleration due to gravity (approximately 9.81 m/s²).

Ah = 0.16 x 9.81 m/s² = 1.57 m/s²

Earthquake Load:

EQL = R x (DL_total + LL_total) x Ah

EQL = 5.0 x (13.5 kN/m² + 5.0 kN/m²) x 1.57 m/s² = 104.08 kN/m²

2. Design a simply supported gantry girder to carry electric overhead travelling crane

Given:

Span of gantry girder = 7 m

Span of crane girder = 9 m

Crane capacity = 250 kN

Self-weight of trolley, hook, electric motor etc. = 40 kN

Self-weight of crane girder excluding trolley = 100 kN

Minimum hook approach = 1.0 m

Distance between wheels = 3 m

Self-weight of rails = 0.2 kN/m

Given

Moment Load of maximum moment

Crane capacity + Self weight of trolley

250 + 40 = 290 kN

Self weight of the crane girder is 100 kN

For maximum reaction on gantry girder, The moving load should be as close to gantry as possible.

MB=0

RA x 9 – 290 x 8 -100 x 4.5 = 0

9RA = 290 x 8 + 100 x 4.5

RA = 290 x 8 + 100 x 4.5 / 16

= 173.12 kN

This load is transferred to gravity gantry girder through two wheel

The wheel base being 3 m

Load gantry Girder from each wheel = 173.12/2 = 86.56

Factored wheel load = 186.56 x 1.5 = 129.87 kN

Maximum moment due to maximum loads of calls under a wheel when the center of gravity of wheel load and the wheel are equidistant from the center of gravity

MB=0

-RB x 7 + 129.84 x 2.25 + 129.84 (4.5+0.75)=0

7RB = 129.84 x 2.25 + 129.84 (4.5+0.75)

RB = 129.84 x 2.25 + 129.84 (4.5+0.75)/7

RB = 486.9 kN

Max Moment ME = Force x Perpendicular

ME = 486.9 x 3.75

= 1825.87 kNm

25% of ME = 0.25

Moment due to Impact = 0.25 x 1825.87

= 456.46 kNm

Assume self weight of girder = 2kNm

Therefore DL due to self weight + rails = 2 +0.2

= 2.2 kNm

Factored DL = 2.2 x 1 = 2.2 kNm

Moment due to DL = 2.2 x 7² / 4.5 = 23.95 kNm

Max moment ME + Moment due to Impact + Moment due to DL

1825.87 + 456.46 + 23.95 = 2306.28 kNm

MAX MOMENT DUE TO HORIZONTIAL FORCE

Horizontial force transfers to rail: 10% of weight to rail + load lifted

10/100 (250 + 40) = 29 kN

Assume double frame wheel, This is distributed over 4 wheel = 29 / 4 = 7.25

Factored horizontial force on each wheel = 1 x 7.25 = 7.25

For maximum shear force on the girder the trailing Wheel should be just on the girder

Therefore vertical shear due to wheel loads = 129.84 + 129.84 x 3.5 / 7 = 194.76 kN

Vertical due to impact = 0.2 x 194.76 = 39.35 kN

Vertical shear due to self weight = 2.2 x 7 / 2 = 7.7 kN

Total vertical shear = 194.76 + 39.35 + 7.7

= 241.81 kN