A towering achievement

By BCA

Professional Engineers play an important role in our built environment, ensuring the safety of our buildings while transforming the way we build Singapore. The Building and Construction Authority (BCA)’s Design and Engineering Safety Award (DESA) honours Singapore’s best engineering talents who have developed creative engineering solutions to overcome challenging architectural designs and site constraints to bring their projects to their safe completion.

In 2019, five Professional Engineers were commended under the DESA. Of the five, three Professional Engineers were given the Excellence Award. One of them was Engineer (Er) Kam Mun Wai, Senior Executive Director at Meinhardt Singapore, for Frasers Tower.

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“The site is located in the densely-populated city centre,” Engineer (Er) Kam shares. “It is surrounded by three buildings in close proximity – the Telok Ayer Chinese Methodist Church, The Clift condominium, and the Bangkok Bank Building.” Telok Ayer Chinese Methodist Church has been a designated National Monument since 1989.

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Er Kam’s challenges for this project were the variable ground conditions which affected how he had to design its structural foundation, the site’s close proximity to the other buildings in the dense city centre, and its architectural design with the façade sloped at a five-degree angle.

Solutions for stability

To protect the structural integrity of the adjacent buildings – including the monument, Er Kam devised a solution using earth retaining wall structures and a “top-down” construction method to minimise any ground movement during construction.

In catering for the building’s angled façade, he designed a complex but robust system of structural elements by analysing the forces and loads that were exerted to each element, while keeping to its architectural design. He also designed the building’s foundation such that it optimises the favourable ground conditions, reducing the amount of materials and resources needed for its construction.

In terms of overall building stability, Er Kam says, “As a building gets taller, the effects of lateral loads, especially wind pressure, will be greater. The increase in lateral loads is exponential with height.

“The design of the building lateral load resisting system has to be robust to transfer both gravity and lateral loads to the foundation. The structure has also to be rigid enough to control the building deflections to permissible limits.”

All high-rise buildings are also subject to lateral and torsional deflections.

“When a tall building is subject to strong winds, the resulting oscillatory movements may induce a wide range of responses on its occupants, sometimes causing discomfort,” Er Kam explains. “Therefore, the design of the building structure must satisfy the comfort criteria for its intended use, with a low probability of exceeding.”

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Safety and innovation in design

Er Kam says the process of identifying safety challenges isn’t a one-man show. To him, a large contributor to the safety mindset is sometimes as simple as getting a second opinion.

He says, “We are always in the process of learning. In the event of doubt, a second opinion would help. Never hesitate to discuss with a fellow professional or with someone who has the related experience or expertise.”

In addition, his approach to safety in construction comes from close monitoring while things are underway. “A lot of money is spent on implementing the instrumentation programme,” Er Kam quips. “But there may not be enough attention spent on understanding and interpreting the monitoring results.

“Every monitoring result is telling us something. Timely assessment of the results, and taking appropriate action immediately, will help to prevent surprises later.”