Live Loads

Allinterior floors $2\mathrm{.}5$kN$/$m$2$

Roof and Cantilevers$1\mathrm{.}5$ kN$/$m$2$

Assume that design wind loadand earthquake loadare negligible for location of the building structure.

Floor Slab

Concrete Grade $35$ MPa

In$-$situ RC Roof and Precast Concrete Floor Slab Thickness$-200$mm

Precast Concrete Floor Decking $-$Width $1\mathrm{.}5$m x Span $3$m

Simply Supportedon secondary steel beams

Secondary Steel Beams$(457$x$152$x$74$ UB$)$

Steel Grade S$275$

$7\mathrm{.}5$ m spanning and simply supported between primary steel beams

Primary Steel Beams$(610$x$229$x$101$ UB$)$

Steel Grade S$275$

$9$ m spanning and simply supported between steel columns

Steel Columns$(305$x$305$x$118$ UC$)$

Steel Grade S$275$

Walls

External Wall self$-$weight$-4$kN$/$m$2$

Interior Partition Wallself$-$weight$0\mathrm{.}75$kN$/$m$2$Legend:PB $-$Primary Beam $(610$x$229$x$101$UB$)$floor slab spanning direction

SB $-$Secondary Beam $(457$x$152$x$74$UB$)$

In determining the following maximum external support reactionsand internal member forces, you are required to make reference to the appropriate specific clauses of the localCode of Practices $($CoP$).$

$($a$)$ By neglecting the small self$-$weight of the beam material, determine design support reactions for the cantilever beam B$4$a and sketch its Shear Force and Bending Moment Diagrams.

$($b$)$ Check the appropriateness of the above$-$given dead load and live loads in compliance with the local Code of Practice. Discuss the statutory $/$ specification requirements to be considered to ensure structural designs are safe.

$($c$)$ State the dead load and imposed load factors and the related material resistance factors with reference to the local Code of Practice.

$($d$)$ Indicate all critical design force values on the sketches.

$2$

$($a$)$ Use deflection formulas to calculate the deflection at the mid$-$spanof the beamB$4$a under the design loads and Assume all Primary Beams B$3$b are simply supported by thesteel columns. Use deflection formulas to calculate the deflection at the mid$-$span of the beam B$3$b under the design loads.

$($b$)$ If the columns on both sides of a long spanning Primary Beam are tall and slender, what will be effect of large mid span deflection of the Beam on the overall structural stability of the framework. Explain the scenario with an illustration of the deflected shape of the structure.

$($c$)$ If all Primary Beams B$3$b are fully fixed to the steel columns instead of simply supported, what will be the deflection at itsmidspan? If theprojectionofthe exteriorbeamB$3$a is increased from $1\mathrm{.}5$ m to $3$ m and its free end is held up by a steel tie member inclined at $45$to the horizontaland attached to the vertical column, calculate the reduction in the deflection at the free end of the beam compared with the cantilever support arrangement.

Explain the scenario with an illustration of the deflected shape of the structure and how to resist deflections in beams regarding structural stability.

$3$

$($a$)$ Determine the slenderness and effective length of the steel columnC$0$b$.$ Describethe concepts of slenderness ratio and effective length on a column.

$($b$)$ Calculate the design axial load.

$($c$)$ What will be reduced axial load capacity of the column C$0$b $(305$x$305$x$118$ UC$)$ if there will be reduction of $2$ mm of the steel material due to surface corrosion after $50$ years of service? Explain how the steel column C$0$b could be analyzed and strengthened to take a greater axial load and column moment.

$($d$)$ For a very tall multistory building located in a verybusy town center, what will be the most effective support methods for slab, beam and column support methods in designand construction of its structural frame? You should consider different buildability factors including ease of construction, economics,safety and environmental aspects.

$4$

$($a$)$ Check the structural adequacy of the steel column C$0$b using $305$x$305$x$118$ UC structural section for maximum design axial load $($assume small eccentricity of the axial load$).$ The floor height shall be $4$ m$.$If an RC square section of $400$x$400$ is adopted for the column C$0$b rather

than steelwork in order to fulfill the corrosion and fire resistance, you are required to carry out the alternative structural design for the RC column section, i$.$e$.$ to determine quantity of main compression steel and link reinforcements of the column section. Assume concrete Grade $35$ is used.

$($b$)$ Sketch and specification of the RC detail for RC column section.

$($c$)$ Discuss the pros and cons in selection of structural materials between reinforced concreteandsteelwork for the structural frame construction for the above building structure with regard to fire resistance,corrosion resistance, quality control, time for project completion and other project management requirements.

$($d$)$ Finally, you are asked toprovide a brief assessment of how BIM may benefit the practice in terms of the production and management of information, and collaboration with other professions.Q