Imagine Earth with surface gravity of 14.7 m/s² instead of 9.81. Not a different planet — same rock, same materials, same ambitious engineers. How would our built world have to change?

The square-cube law comes for your buildings first. A structural column's load-bearing capacity scales with its cross-sectional area (length²), but the weight it supports scales with volume (length³). Increase gravity by 50%, and every vertical load increases by 50%. A steel column rated for a 10-story building now fails somewhere around the 7th floor unless you beef it up.

Let's run the numbers on a standard W14×90 wide-flange steel column, a workhorse of mid-rise construction. Its axial capacity is roughly 5,300 kN. A typical office floor contributes about 500 kN of tributary load per column. At normal gravity, that's good for 10 floors (5,000 kN, leaving margin). At 1.5g, each floor now imposes 750 kN, so the same column maxes out at 7 floors. To reclaim your 10 stories, you'd need to jump to a W14×132 — 47% heavier per meter of column. And that extra column weight itself adds load, cascading through the structure.

Foundations get brutal. Soil bearing capacity doesn't change (it's a material property), but the building pushing down on it weighs 50% more. A mat foundation that was 1.2 meters thick now needs to be roughly 1.8 meters. Pile depths increase proportionally. The cost of going vertical skyrockets — literally and financially.

The real casualty: long-span structures. A cable-stayed bridge's main span is limited by the cable's ability to support its own weight plus the deck. The Millau Viaduct's longest span is 342 m, with cables of about 55 strand bundles. The self-weight sag of a cable scales linearly with g. At 1.5g, either you accept 50% more sag (destroying your road geometry), add 50% more cable steel (which adds its own weight), or shorten your spans to around 250 m. The era of dramatic long-span bridges retreats by decades of engineering progress.

What about people? A 75 kg person would feel like they weigh 112 kg. Stairs become miserable. The human heart pumps against a hydrostatic column that's now 50% heavier — blood pressure in your feet while standing would jump from about 100 mmHg above heart-level to 150 mmHg. Varicose veins would be universal. Buildings would max out at 3–4 stories before accessibility collapsed, pushing civilizations outward rather than upward. Elevators wouldn't be a luxury — they'd be a medical necessity above the second floor.

One surprise winner: arch structures. Arches transfer loads in pure compression, and stone and concrete are magnificent in compression. A Roman-style stone arch bridge barely notices the extra gravity — the compressive stress in the voussoirs increases by 50%, but stone can handle compressive stresses of 30–100 MPa, and a typical arch bridge operates at 2–5 MPa. Arch architecture would dominate. Gothic cathedrals, with their flying buttresses channeling forces into compression paths, would be the template for everything.

Material science shifts too. Timber construction effectively dies for anything structural — wood's strength-to-weight ratio can't compete when weight is the enemy. Ultra-high-performance concrete (150+ MPa compressive strength) and high-strength steel become baseline materials rather than specialty ones. Bamboo, with its exceptional tensile strength-to-weight ratio, might actually gain favor for reinforcement applications.

The built environment of a 1.5g Earth would look surprisingly ancient in aesthetic: wide, squat, arch-heavy, and sprawling. The skyscraper would be a marginal curiosity rather than the defining form of modern cities.