We asked our principals what their favorite structures are on Earth. This week, Guy Conversano (pictured above listening to a museum curator) gave us his selection of structural marvels. He discovered one of them during his recent trip to Singapore. Learn about what strikes his fancy and read how the structures were accomplished too.

Hoover Dam: The multi-functional Hoover Dam was built to tame the Colorado River, protect Nevada and Arizona from floods, generate hydroelectricity, provide agricultural irrigation, and supply water to the city of Los Angeles. It’s a concrete gravity dam, meaning the dam’s weight resists the force of the water pressure from Lake Mead. The dam’s curvature also redirects and dissipates the water pressure equally on the Arizona and Nevada canyon walls. The push-back water counteracts with the water current from the lake. This subtle action squeezes the 1,244-foot long concrete arch together creating the rigid strength of the Hoover Dam.

“It’s amazing the workers used over 4 million cubic yards of concrete to build this dam,” Guy said.

The dam is as tall as a 60-story building (726 feet) from the base to the crest. The engineers from the Bureau of Reclamation designed the dam so it could be built in vertical concrete column blocks. The engineers also had a say on how the concrete cooled when making the interconnecting blocks. The construction crew embedded 1-inch steel pipe when pouring the block forms. Cold water from the lake ran through the pipes and assisted with curing. After the block cured, the pipes were filled with concrete to add strength. Grout was then applied to the spaces between the vertical block columns to create a uniform concrete structure.

The Interlace: Guy traveled to the island city/state of Singapore last year for a sustainability tour. During his visit he saw The Interlace, an expansive contemporary residential development designed by Ole Scheeren. Completed in 2013, the Interlace won the Urban Habitat Award from The Council on Tall Buildings and Urban Habitat (CTBUH). The jury commended the smart architecture that creatively accomplishes a different typology for high-rises by turning them into horizontal “towers in the park.”

The 1.8 million-sf interconnected concrete complex is affordable housing and retail on 20 acres of greenbelt landscape. There are 31 apartment blocks that are 230 feet long and 54 feet deep with some rotated at 120 degrees. Arranged in a hexagon pattern, the building varies in height from six stories to 24 stories. Six columns support the above-grade levels at the intersecting points where the blocks overlap. The stacking arrangement also allowed for cantilevers and bridges to be built around the exterior spaces. There is an abundance of spacious courtyards, roof gardens, and landscaped terraces for community interaction. In Singapore, the amount of land a new building takes up must be “given back” 100% in reintroduced green space from the building. The architects were able to contribute 112% from The Interlace.

“I love the simplicity of the stacked design and you still wonder how it was done,” Guy said. “It’s impressive how they handled the long spans, cores, and exits for an expansive project like that.”

The Interlace’s design proved that developers don’t have to sacrifice quality experiences or aesthetics while making a building comply with strict building regulations and maintaining budget feasibility. With Singapore’s predicted population growth, residents are eager for more affordable housing that respects the environment and prepares the island for the future.

The next time we run a “Staff Picks” blog post, discover Mark Aden’s favorite structures in the world.