[itsmartapuntocm]

"If you're building a skyscraper out of reinforced concrete, the only way for it to be stable is to design it in the shape of a pyramid."

Except the Petronas Towers in Kuala Lumpur are standard supertalls built out of reinforced concrete?

[lqet]

But not "standard" reinforced concrete:

> Due to the huge cost of importing steel, the towers were constructed on a cheaper radical design of super high-strength reinforced concrete. High-strength concrete is a material familiar to Asian contractors and twice as effective as steel in sway reduction; however, it makes the building twice as heavy on its foundation as a comparable steel building. Supported by 23-by-23 metre concrete cores and an outer ring of widely spaced super columns, the towers use a sophisticated structural system that accommodates its slender profile and provides 560,000 square metres of column-free office space. [0]

[0] https://en.wikipedia.org/wiki/Petronas_Towers

[adrian_b]

Looking in Wikipedia, they still have a section that diminishes with the height and they are made of some special "super high-strength reinforced concrete".

Even by using this special reinforced concrete, the towers are twice heavier than if they had used a steel structure.