In 2015, when the project team was confronted with the complex con - structability challenges and confinement reinforcement design issues for the construction of the world’s 2nd tallest building, they turned to BauGrid Reinforcement for solution. This extraordinary project, Merdeka PNB-118 (aka PNB-118), is a 118-story, 644 m (2,113 ft) tall Skyscraper that is nearing completion in Kuala Lumpur, Malaysia. It is currently the tallest building under construction in the world. The structure with its exclusive spire was inspired by and resembles a unique silhouette of Malaysia’s then Prime Minister, raising his hand during the 1957 assembly at this site, while chanting “Merdeka” (which means “Independence”), marking their independence from Great Britain. The designers of super tall concrete structures who need to provide for resistance to high axial compressive forces, strong cyclone or typhoon winds, and blast forces, must consider the balance of strength and duc - tility in their design approach. Increasingly, engineers are specifying higher strength concrete while the ductility is maintained through care - ful detailing of the reinforcing. When properly designed and detailed, it is the transverse reinforcement that provides the concrete with ductil - ity through enhanced confinement of the longitudinal reinforcing steel. Since early last century, this has been achieved by using closely spaced hoops, stirrups, and crossties. However, today’s mega tall structures, designed in accordance with the more stringent code requirements for this century, require rebar bends, hooks, and hook extensions in their transverse assemblies that, quite often, result in labor-intensive construc- tion, reinforcement congestion, and concrete placement challenges. BauGrid®Reinforcement Enables the World’s Second Tallest Building to Soar into the Skies of Kuala Lumpur By Al Anvari, P.E.
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One-piece BauGrid reinforcement can replace the many pieces of conventional transverse reinforcement. The resistance-welded inter- sections replace cumbersome end hooks and provide a more exact and efficient system for placement of longitudinal and confinement reinforcement. The system significantly improves forming and con- crete placement, enhancing concrete consolidation and increasing construction speed. The Design Engineers and Construction Team for PNB-118 Tower se- lected BauGrid Reinforcement in the most congested column sections of the core wall, at the lower levels of the structure. Many large U.S. and international engineering and construction companies had already discovered the benefits of this transverse reinforcement system by completing many important projects, such as the 60-story residential tower in San Francisco to mark the tallest reinforced concrete structure in California, USA; the world’s tallest precast concrete structure in the region of highest seismicity in San Francisco, USA; and the world’s tallest tunnel form structure, built in the most severe earthquake zone,
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csengineermag.com
November 2021
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