This time of year, bushels of rhubarb, potatoes, and lettuce can be harvested in abundance at the People’s Pantry, a community garden that doubles as a fresh food pantry in Blackpool, England.

This type of concrete has a higher percentage of cement in the blend so it sets up faster than standard concrete mix. You can walk on it within 10 to 12 hours, compared with several days.

Self-consolidating concrete: Self-consolidating concrete is a form of concrete that sets and hardens quickly, without cement mixers. It can be poured under water, and once it’s dry, it will ...

ANSWER: The words are often used interchangeably. While the two materials are related, in reality, they are quite different.

When trillions of gallons drench a typical concrete-dominated cityscape, the water runs off rooftops and slides onto impermeable concrete driveways and into streets, turning them into virtual rivers.

We know that concrete derives its strength from a mixture we call calcium aluminate silicate hydrates, or CASH. But we don’t know how Romans combined it all to get that mixture.

But it is much less resilient than the concrete used in Roman times; over the course of decades, it develops cracks that, by letting water in, can eventually destroy the material.