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7/30/2019 Composit Report
http://slidepdf.com/reader/full/composit-report 1/5
Design Parameters
Concrete Grade 25N/mm2
Concrete Cover 25mm
Density of Concrete 25kN/m3
Strength of Structural steel 275N/mm2
Method of construction Propped
Imposed Loads
Description Old design Design review
Live load 5kN/m2 5.0 kN/m2
Wall loads 5 kN/m 15.75 kN/m2
Steel sections
PB 350X175 x49.6kg/m
PB1 350X175 x 41.4 kg/m
SB 250x125 x25.7 kg/m
Analysis Models
7/30/2019 Composit Report
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Design and Analysis Out put
Cross Girder SB
Deflections old SLS 51 mm
LL 29 mm
Deflectionsreview SLS 64 mm
LL 42 mm
Ultimate Moments Mu old 162 kNm
Mu review 162 kNm
Shear Force Fu old 92 kN
Fu review 92 kN
DescriptionStatus
old reviewBending Strength 0.94 0.94
Shear Strength 0.34 0.34
%Composite
Action 74.10% 74.10%
Strength 179 179
Strength for Full
comp action
100% 100%
196 196
Capacity ratio Full 0.826 0.826
Design Models
Main Girder PD
Deflections old SLS 16 mm
LL 9 mm
Deflectionsreview SLS 21 mm
LL 13 mm
Ultimate Moments Mu old 358 kNm
Mu review 358 kNm
Shear Force Fu old 187 kN
Fu review 187 kN
DescriptionStatus
old reviewBending Strength 1.15 1.15
Shear Strength 0.38 0.38
%Composite
Action 21.30% 21.30%
Exist strength 321 321
Strength for Full
comp action
100% 100%
416 416
Capacity ratio Full 0.86 0.86
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Perimeter Cross Beam
Deflections old SLS 20 mm
LL 11 mm
Deflections
review SLS 55 mm
LL 16 mm
Ultimate Moments Mu old 89 kNm
Mu review 241 kNm
Shear Force Fu old 52 kN
Fu review 141 kN
DescriptionStatus
old review
Bending Strength 0.54 1.41
Shear Strength 0.2 0.53
%CompositeAction 74.10% 74.10%
Strength 171 171
Strength for Full
comp action
100% 100%
181 181
Capacity ratio Full 0.49 1.33
7/30/2019 Composit Report
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Conclusion
Girder PB
Provided structural steel sections for main Girders are satisfy for both strength and deflection if full composite
action is being used. But due to lack of shear studs used in the constructions, full composite action is not mobilized,
consequently moment capacity and stiffness of the composite beams reduces. Therefore, provided steel girder fail
under then reduce design ultimate loading. While make the adjustment to the live load to consider the stores of height equivalent to 3m, Girder will not further satisfy. However, for working load, the provided section is satisfied
subjected to plastic moments and large deformations.
Therefore it is recommended to increase the capacity of the section by adding additional section (same size) or
welding additional plate (10mm) to the bottom of flange of the girder. Contractor is asked to submit the method
statement for review.
Cross girder SB
Provided section is marginally satisfy for the given loading. But, full composite action is not mobilized due to lack
of shear studs. Although relative deflection is satisfy, overall deflection (50mm) is passing the code limit.
Therefore, damages to the underneath partition is expected. Slight modifications is required to satisfy the additional
live loads
Perimeter Cross Beam
In the design, light weight partitions along the perimeter have been considered, but at the site, solid block work was
used. Therefore perimeter beam is subjected to unexpected additional load and the existing steel structural beam is
not adequate for the purpose. Therefore it is recommended to increase the capacity of the section by adding
additional section (same size) or welding additional plate (10mm) to the bottom of flange of the girder. Contractor is
asked to submit the method statement for review.
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Recommendations
Contractor is asked to submit the method statement about the rectifications to be done. All the rectifications should
be done at the zero imposed loading conditions, as structure is safe without imposed loads. It is recommended to
jack the beams where higher amount of deflections were detected before doing the rectifications. Following
recommendations will be adopted as possible rectifications methods
Perimeter Cross Girder
Weld 125X10mm steel plate 10mm Thick) along the bottom flange of the Steel Girders SB at the edge of the slabs
and weld stiffeners (5mm thick plates) to the web at the either side of the girders (all the SB Girders) at the interval
of 300mm between first 2m from the supports and rest of the beams at the interval of 600mm
Girder PB
Weld 175X10mm steel plate 10mm Thick) along the bottom flange of the Steel Girders SB at the edge of the slabs
and weld stiffeners (5mm thick plates) to the web at the either side of the girders (all the SB Girders) at the interval
of 300mm between first 2m from the supports and rest of the beams at the interval of 600mm.