Construction World December 2021

For the des ign of the columns , a sophi st icated approach was requi red to enable strength

cons iderat ions to be opt imi sed wi thin the constraints of the project budget . For instance, the heavi ly loaded columns towards the bottom of the bui lding requi red high strength concrete (60 MPa) , whi le the slabs only needed to be a standard concrete strength (30 MPa) and i t was uneconomical to use a high-strength concrete. However, typical construct ion methodology employed in cast ing slabs onto columns resul ts in port ions of the column concrete having a lower strength. Thi s lower strength area had to be accounted for to ensure that the force in the column could be transmi tted through i t . To f ur ther comp l i cate thi s , the bu i l d i ng compr i sed three uni que occupancy t ypes , name l y reta i l ( two l eve l s ) , park i ng (ni ne l eve l s ) and res i dent i a l ( 25 l eve l s ) . The co l umn l ocat i ons for the three occupanc i es d i f fered f rom one another, whi ch resu l ted i n e i ther l arge , heav i l y l oaded t rans fer beams or co l umn t rans i t i ons wi th s i gni f i cant eccent r i c i t i es that had to be des i gned for. For some i nstances , three -d imens i ona l , non- l i near f i ni te e l ement br i ck mode l s i n whi ch both the conc rete and re i n forcement were mode l l ed to check conc rete st ra i ns . Thi s a l so requ i red the use o f i nternat i ona l des i gn codes and spec i a l i st techni ca l l i terature . A s there was l i t t l e marg i n i n the budget to ensure that the bu i l d i ng was f i nanc i a l l y v i ab l e , most e l ement s had to be i nd i v i dua l l y des i gned and opt imi sed to a ut i l i sat i on rat i o o f around 90%. Thi s requ i red the utmost under stand i ng i n order to do so. I n add i t i on , a BIM mode l was used to est imate cost s for each e l ement and prov i de proj ected est imates to ensure that the st ructura l cost o f the bu i l d i ng was wi thi n budget . 

system wi th large counterweights on the street s ide stabi l i s ing the f ragi le façade wal l . Thi s al lowed uninterrupted construct ion of the bui lding, whi le the wal l was kept safely in place. Once the parking levels behind the wal l were bui l t , the wal l was t ied into the concrete floors us ing movement-compensat ing connect ions , al lowing the steel bracing to be removed. An essent ial requi rement for development approval , retaining the heri tage façade creates an eye- level experience that blends in seamlessly wi th the surrounding area. To be able to accommodate the requi red number of parking spaces wi thin the bui lding’s footprint , a compressed central l i f t and stai r core was des igned: an al ternat ive to the decentral i sed l i f t and stai r core on tradi t ional tal l bui ldings . However, the compressed central l i f t and stai r core meant the lateral structural stabi l i ty in the shorter di rect ion of the bui lding was compromi sed. Ini t ial thinking on reducing potent ial lateral dri f t under wind load was to use outrigger wal ls , which st i f fen the core by connect ing i t to enlarged perimeter columns on the upper levels of the bui lding – resul t ing in a ‘push-pul l ’ ef fect between the core and the enlarged columns , and cons iderably enhancing the lever arm of the force- res i st ing mechani sm. The height of the structure of 120 m above ground level , together wi th the relat ively smal l s i te created s igni ficant geometric restraints , made the des ign of the bui lding more compl icated than convent ional bui ldings in terms of gravi ty and lateral des ign perspect ives .

PROJECT INFORMATION

• Company entering: Zutari • Project start date: March 2018 • Project end date: April 2021 • Client: FWJK Developments • Main Contractor: Concor Construction • Architect: FWJK Developments • Principal Agent: FWJK Developments • Project Manager: Orion Project Managers • Quantity Surveyor: FWJK Quantity Surveyors

• Consulting Engineer: Zutari • Structural Engineer: Zutari • Civil Engineer: Zutari

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20 th Best Project Awards 2021