Construction World December 2020

Category: SPECIALIST CONTRACTORS OR SUPPLIERS

DURBAN HEIGHTS RESERVOIR 3 Durban Heights Reservoir 3 is a 350 M ͏ reservoir situated just outside the Durban CBD, in the suburb of Reservoir Hills, KwaZulu-Natal.

T KLV UHVHUYRLU ZDV FRQVWUXFWHG LQ DQG is one of the biggest concrete reservoirs in 6RXWKHUQ $IULFD ,W VXSSOLHV SRWDEOH ZDWHU WR RYHU ͤYH KXQGUHG WKRXVDQG SHRSOH LQ 'XUEDQ DQG WKH VXUURXQGLQJ DUHD 7KH UHVHUYRLU design is unique in the sense that it has a single support in the middle and the roof is VKDSHG OLNH D FLUFXV WHQW 7KH URRI LV PDGH XS RI VWHHO SRVW VWUHVVHG FDEOHV WKDW UDGLDWH from the centre roof support to the outer base VXSSRUW ZKLFK DJDLQ VXSSRUWV SUHFDVW SDQHOV 7KH WRWDO URRI DUHD LV DERXW P (DFK SRVW WHQVLRQHG FDEOH FRQVLVWV RI [ PP PLOG VWHHO VWUDQGV SURWHFWHG E\ D PHWDO GXFW ͤOOHG ZLWK D ELWXPHQ mastic – an engineering masterpiece in LWV HQWLUHW\ ,Q 8PJHQL :DWHU HQJDJHG ZLWK civil engineering consultants, requesting a full diagnostic survey of the concrete roof SDQHOV 7KH REMHFWLYH RI WKH VXUYH\ ZDV ͤUVW to establish the current condition of the roof panels, and then to establish an effective repair and rehabilitation strategy, which would DOVR EH DSSOLHG WR IXWXUH UHSDLU SURMHFWV 7KH varied diagnostic survey included testing of chloride ingress, carbonation ingress, and H[LVWLQJ FRYHU WR UHLQIRUFLQJ $ YDULHW\ RI LVVXHV ZHUH LGHQWLͤHG EXW RI LQWHUHVW ZDV the existence of a micro-climate within the UHVHUYRLU ,W ZDV QRWHG WKDW ZKHUH WKH URRI

VRͦW DW RQH SRLQW WRWDOO\ VDWXUDWHG ZDV IRXQG WR EH SHUIHFWO\ GU\ LQ D IHZ KRXUV 7KLV ZHW DQG GU\ F\FOH ZDV IRXQG WR EH D GDLO\ RFFXUUHQFH This micro-climate with wet dry cycles creates a favorable environment for contaminants to be absorbed into the reinforced concrete SDQHOV FDXVLQJ FRUURVLRQ RI WKH UHLQIRUFLQJ Based on the original diagnostic survey, rehabilitation proposals and the subsequent product trials, the Sika solutions and innovative products were deemed the best SHUIRUPLQJ UHSDLU V\VWHP IRU WKLV SURMHFW )ROORZLQJ WKH ͤQDO WULDO UHVXOWV 8PJHQL :DWHU appointed Royal HaskoningDHV to take on this UHKDELOLWDWLRQ SURMHFW DQG 6LND SURGXFWV ZHUH VSHFLͤHG RQ WKH WHQGHU 7KH SURMHFW HQJLQHHU Royal HaskoningDHV compiled Tender Documentation for the repair and rehabilitation RI WKH 'XUEDQ +HLJKWV 5HVHUYRLU FRQFUHWH URRI VWUXFWXUH 6PDUW &LYLOV &RQVWUXFWLRQ D specialised civil contractor, was appointed as WKH VXFFHVVIXO WHQGHUHU 6PDUW &LYLOV LQYHVWLJDWHG WKH SURMHFW̵V next challenge namely identifying alternative methods of gaining access to the roof VWUXFWXUH DQG VKRUWHQLQJ WKH UHSDLU WLPH 7KH original scope of works involved a moveable gantry that allowed access to the roof, but the ZRUN DUHD ZDV RQO\ P ZLGH DQG WKXV OLPLWHG the reach over the entire roof to increments RI P 7KLV SXW FRQVWUDLQWV RQ ERWK ZRUN

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2020