Construction World December 2019

DESIGN AND CONSTRUCTION OF THE 1 400 MVA SEBENZA SUBSTATION A large portion (eastern third) of the City of Johannesburg has for many years been supplied with bulk electrical power at 88 kV from the Kelvin Power Station (Kelvin), via a bulk power line corridor consisting of 16 power line circuits. Over the years the load has grown to the present ± 450 MVA.

K elvin is an old power station and the generation is greatly GHSHQGHQW RQ WKH SHUIRUPDQFH RI WKHLU DJLQJ JHQHUDWLRQ ͥHHW The integration of the planned new Modderfontein development LQWR WKH -RKDQQHVEXUJ 0HWUR ZLWK DQ XOWLPDWH ORDG RI s 09$ ZRXOG DOVR LQFUHDVH WKH GHPDQG RQ WKH &LW\ 3RZHU QHWZRUN FRQVLGHUDEO\ 7KH QHHG IRU WKH XUJHQW GHYHORSPHQW RI DQ DGGLWLRQDO EXON LQIHHG SRLQW IURP (VNRP LQ FORVH SUR[LPLW\ WR .HOYLQ ZDV LGHQWLͤHG LQ WKH &LW\ 3RZHU (OHFWULFDO 0DVWHUSODQ RI ,Q EULHI (VNRP QHHGHG D ED\ N9 GRXEOH EXV EDU WUDQVPLVVLRQ VWDWLRQ WR FDWHU IRU WKHLU ORQJ WHUP SODQQLQJ :KLOH &LW\ 3RZHU VLPLODUO\ LGHQWLͤHG WKH QHHG IRU D 09$ N9 GRXEOH EXV EDU VXEVWDWLRQ ZLWK D PLQLPXP RI RXWJRLQJ FLUFXLWV WR FDWHU IRU IXWXUH QHHGV ,Q DGGLWLRQ .HOYLQ LQ WHUPV RI WKHLU 33$ ZLWK &LW\ 3RZHU ZHUH FRQWUDFWHG WR VXSSO\ 09$ JHQHUDWHG SRZHU LQ DQ 1 FRQͤJXUDWLRQ WR WKH &LW\ YLD WKH QHZ 6HEHQ]D VXEVWDWLRQ ZLWK WKH RSWLRQ WR XSJUDGH WR WZR 09$ VXSSOLHV LQ WKH IXWXUH 36: &RQVXOWLQJ (QJLQHHUV 36: DV D VWUDWHJLF SDUWQHU RI &LW\ 3RZHU RI -RKDQQHVEXUJ &LW\ 3RZHU ZDV DSSRLQWHG LQ WR conduct a feasibility study on the optimal positioning for such a QHZ LQIHHG VXEVWDWLRQ 6HYHUDO DOWHUQDWLYH SRVLWLRQV DQG VXEVWDWLRQ FRQͤJXUDWLRQV ZHUH FRQVLGHUHG GXULQJ WKLV VWXG\ VXFK DV SK\VLFDO SRVLWLRQ WUDGLWLRQDO RXWGRRU OD\RXW YHUVXV FRPSDFW FRQͤJXUDWLRQV W ith this serious lack of suitable student accommodation in FORVH SUR[LPLW\ WR WHUWLDU\ LQVWLWXWLRQV 6RXWKSRLQW -RULVVHQ Street has been built to provide student accommodation that is VLWXDWHG DFURVV WKH URDG IURP :LWV 8QLYHUVLW\ RQ -RUULVVRQ 6WUHHW This 18 storey building has been designed to provide the maximum amount of student accommodation units while remaining DHVWKHWLFDOO\ SOHDVLQJ E\ HPSOR\LQJ WKH ODWHVW LQ VSDFH VDYLQJ GHVLJQ WHFKQRORJ\ DQG ͤWWLQJV ZKLOH HQVXULQJ RSWLPDO TXDOLW\ RI OLIH IRU WKH VWXGHQWV The site chosen for the development had a few very old 2 and 3 storey uninhabitable buildings in a very bad state that had to EH GHPROLVKHG 7KH VWRUH\ EXLOGLQJ ZLWK D ͥRRU RI EDVHPHQW SDUNLQJ SURYLGHV EHGV RQ ͥRRUV ZLWK FRPPRQ DUHDV WKDW LQFOXGH VSDFHV IRU UHFUHDWLRQ FRPPXQDO VWXG\ DUHDV DQG ZLWK WKH JURXQG ͥRRU EHLQJ D GHͤQHG UHWDLO DUHD IRFXVHG RQ WKH QHHGV RI WKHVH VWXGHQWV The Southpoint Jorissen Street Student Accommodation project commenced in February 2018 and is expected to be FRPSOHWHG LQ 1RYHPEHU LQ WLPH IRU WKH DFDGHPLF \HDU WKH ͤUVW JUHHQͤHOG SURMHFW LQ WKH GRZQWRZQ -RKDQQHVEXUJ DUHD RI %UDDPIRQWHLQ WR EH EXLOW LQ WKH ODVW \HDUV The primary structure has an insitu reinforced concrete frame ZLWK PDVRQU\ SHULPHWHU FODGGLQJ 7KH EXLOGLQJ LV VXSSRUWHG RQ

DV ZHOO DV IXOO LQGRRU DOWHUQDWLYHV 7R DFFRPPRGDWH WKH UHGXFHG land area the PSW design engineers had to utilise their 40+ years RI H[SHULHQFH WR SURGXFH D VROXWLRQ WKDW PHW DOO WKH FOLHQW̵V DQG VWDNHKROGHU̵V UHTXLUHPHQWV ZDV LPSOHPHQWDEOH RI D KLJK TXDOLW\ VWDQGDUG DQG DV FRPSDFW DV SRVVLEOH The most critical engineering challenge of the Sebenza project was to balance and integrate the needs of all the related parties into D VLQJOH EXON LQIHHG VXEVWDWLRQ RQ D UHODWLYHO\ VPDOO VLWH ƒ

• Company entering: 36: 1\HOHWL -9 • Client: City Power of Johannesburg • Main contractor: Consolidated Power Projects PROJECT INFORMATION

SOUTH POINT JORISSEN STREET STUDENT ACCOMMODATION Situated in densely populated Braamfontein, Southpoint Jorissen Street is the first greenfield project to be constructed in downtown Johannesburg in the last 20 years, making this project unique.

370 section precast reinforced 350 x 350 mm cross section FRQFUHWH SLOHV 7KHVH were driven to an average a depth of 26 metres deep into the underlying graben JHRORJLFDO IRUPDWLRQ The weak graben geology and the proximity of the existing

PROJECT INFORMATION

• Company entering: ADA Consulting Engineers • Client: 6RXWK 3RLQW 3URSHUW\ ,QYHVWPHQWV • Start date: 1RYHPEHU • End date: 1RYHPEHU • Main contractor: :%+2 &RQVWUXFWLRQ • Architect: /<7 • Project manager: /<7 • Quantity surveyor: EthiQS • Consulting civil and structural engineers: ADAConsulting Engineers

adjacent buildings dictated the use of

FRQWLQXRXV ͥLJKW DXJHU (CFA) soldier piles to be

used around the perimeter of the property to enable the construction RI WKH EDVHPHQW $SDUW IURP WKH FKDOOHQJLQJ JHRORJ\ RI WKH DUHD and the limited site access due to the nature of construction in a FLW\ HQYLURQPHQW $'$ &RQVXOWLQJ HPSOR\HG D QXPEHU RI LQQRYDWLYH WHFKQRORJLHV RQ WKH SURMHFW RQH RI ZKLFK LV WKH +HEHO %ORFN Due to the size and weight saving provided by the utilisation of +HEHO EORFN WKHUH LV DOVR D VXEVWDQWLDO VDYLQJ RQ FUDQH WLPH ƒ

B E S T P R O J E C T S 2019

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