Construction World December 2020

Category: SPECIALIST CONTRACTORS OR SUPPLIERS

Coreslab helped BMK Consulting Engineers to design an innovative means of fast-tracking the construction of two 100 m long and 3,5 m wide pedestrian bridges in Kaalfontein and Diepsloot. Valued at R14-million each, these construction projects are part of the Johannesburg Road Agency’s significant investment into low-income communities in the larger Midrand area to create jobs and provide access to service delivery. KAALFONTEIN PEDESTRIAN BRIDGE

T he precast-concrete specialist was initially approached to manufacture and supply rib-and-block suspended slab systems WR FRQVWUXFW WKH VXSHUVWUXFWXUH RI WKH WZR EULGJHV +RZHYHU Coreslab suggested a simple but novel alternative design based on hollow-core slabs (HCS) to also overcome some of the site FRQVWUDLQWV RQ WKHVH WZR SURMHFWV 7KLV LQFOXGHG ZRUNLQJ ZLWKLQ proximity to many informal dwellings and limited access to both FRQVWUXFWLRQ VLWHV Coreslab’s design entailed using standard HCS planks, VLJQLͤFDQWO\ OLJKWHU WKDQ D ODUJH VROLG FRQFUHWH ͥRRU VODE RI HTXDO WKLFNQHVV RU VWUHQJWK GXH WR WKH XVH RI IHZHU UDZ PDWHULDOV 7KLV reduces the cost of manufacture and transportation of the slabs to VLWH ZKHUH WKH\ DUH OLIWHG DQG SODFHG OHYHOOHG DQG JURXWHG 7KH +&6 ZHUH SODFHG RQ WRS RI WKH SUHFDVW FRQFUHWH EHDPV WZR SHU VSDQ DQG HDFK P LQ OHQJWK DQG ZHLJKLQJ IRXU WRQV 7KH\ ZHUH WKHQ FRYHUHG E\ D WKLQ PP WKLFN FRQFUHWH VODE 6HUYLFHV ZHUH ͤUVW LQVWDOOHG DQG WKHQ FRYHUHG ZLWK SRO\VW\UHQH PRXOGV ZLWK YRLGV DQG D VWHHO PHVK 7KH FRQFUHWH ZDV WKHQ SODFHG LQ DQ DSSURDFK WKDW UHGXFHG WKH ORDG RI WKH ͤQDO VODE RQ WKH EHDPV The contractor also achieved cost-savings for the client by doing

away with the need for construction materials, including propping DQG FRQFUHWH $QRWKHU PDMRU DGYDQWDJH RI &RUHVODE̵V VROXWLRQ was the extremely high-quality outcome that was achieved the ͤUVW WLPH URXQG E\ RXWVRXUFLQJ WKH PDQXIDFWXUH DQG LQVWDOODWLRQ RI WKH ͥRRU VWUXFWXUH WR D VSHFLDOLVW 7KLV HOLPLQDWHG WKH ULVN RI KDYLQJ WR UHGR ZRUN 1RWDEO\ WKHUH ZHUH QR VDIHW\ RU LQMXU\ UHODWHG LQFLGHQFHV RQ WKHVH SURMHFWV GHVSLWH ZRUNLQJ DW KHLJKWV DQG FORVH WR PDQ\ GZHOOLQJV 3DUW RI WKLV VXFFHVV FDQ EH DWWULEXWHG to the use of

PROJECT INFORMATION

HCS, which were manufactured at ground level in a controlled factory environment and far removed from the many variables encountered on a traditional construction VLWH ƒ

• Client: Johannersburg Roads Agency • Start date: 2018 • End date : 2019 • Main Contractor: Axton Matrix • Project Manager: BMK Group • Consulting Engineer: BMK Group • Specialist Supplier: CoreCivils

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

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2020