Internal Friction Angle of Soil

Internal Friction Angle of Soil

Internal Friction Angle of Soil

07/28/26

“How can we quantify how well soil particles resist shear failure?”

Soil particle bodies will collapse and fail when there’s a large enough shear stress applied to them. But how can we quantify this? Well, what if we were to take the soil body, place it on a theoretical inclined plane, and tilt the platform until the soil body collapses? The angle at which the body collapses is known as the Internal Friction Angle of Soil, and is the most widely used way to measure how well soil particles resist shear failure. The internal friction angle of soil is governed by the equation internal friction angle of soil = tan((shear stress due to friction)/(normal stress acting on soil))^-1. The higher the normal stress on the soil, the more it can resist shear stresses.

Why Flat Roofs Are Not Actually Flat

Why Flat Roofs Are Not Actually Flat

Why Flat Roofs Are Not Actually Flat

07/27/26

“Why are flat roofs not actually flat?”

Building descriptions should be accurate to their name. But flat roofs completely buck this trend. Flat roofs typically have a small degree of slope (typically ten degrees of less) to allow water to runoff the roof to avoid pooling. This is Why Flat Roofs Are Not Actually Flat.

Megasites

Megasites

Megasites

07/26/26

“How can we create large construction-ready sites for giant projects?”

Large construction projects such as new factories or data centers need voluminous amounts of land and infrastructure to support it. Gathering these piecemeal can lead to unbelievable cost overruns and bureaucratic delays. However, developers can purchase Megasites, large contiguous tracts of land that are construction-ready with infrastructure and close to transportation hubs support to remedy this. Megasites commonly complete environmental review ahead of time to ensure policy compliance.

Office Parks

Office Parks

Office Parks

07/25/26

“How can we colocate offices together using urban planning?”

Many white-collar workers are employed in offices. Colocating common-use types in urban districts can improve efficiency. Consequently, municipalities can plan Office Parks that cluster office buildings together to create a sense of cohesion. Office parks may have greenery to improve work-life quality, and may be placed near transit to enable easier commutes.

The Freshwater-Saltwater Interface

The Freshwater-Saltwater Interface

The Freshwater-Saltwater Interface

07/24/26

“What makes the interface between saltwater and freshwater so unique?”

Freshwater and saltwater have substantially different properties. When they meet in coastal aquifers, they form a Freshwater-Saltwater Interface. The freshwater-saltwater interface is a transition zone where freshwater “floats” as a layer above the zone of transition (which in turn “floats” above more pure saltwater) because of saltwater’s greater density. The further down you go in a coastal aquifer, the saltier the groundwater becomes. Coastal aquifer infrastructure operators must be careful with the freshwater-saltwater interface, because overpumping can lead to upconing of saltwater and result in saltwater intrusion.  

Science Parks

Science Parks

Science Parks

07/23/26

“How can universities, governments, and private industries expand research by co-locating workplaces?”

Universities, governments, and private industries can drive scientific and technological innovation. Consequently, it’s a logical step for urban areas to carve out districts for these institutions to work close to each other. These so-called Science Parks facilitate research operations, technology transfer, and knowledge sharing among tenants. If designed well, science parks can superdrive scientific progress. Example science parks across the world include the UCSC Monterey Bay Education, Science & Technology Center, the Metrotech Center at New York University Tandon School of Engineering, Sophia Antipolis in Southeast France, and Saigon Hi-Tech Park in Ho Chi Minh City.

The Roadless Rule

The Roadless Rule

The Roadless Rule

07/22/26

“What’s the U.S.federal rule that protects backcountry forests from road construction, why is it under attack, and what can you do to help?”

Remote, backcountry forests are marvelous pieces of geography. Not only do they nurture diverse ecosystems and regulate our planet’s carbon balance, but they also provide world-class recreational opportunities. In 2001, the U.S. federal government introduced The Roadless Rule, which protects roughly 60 million acres of American backcountry forests and grasslands from road and logging development. This rule has been an incredible success, sustaining not only the forests themselves but also drinking water access to over 25 million Americans. However, this is now all under threat as the USDA released a notice of intent to repeal the roadless rule, likely by (as of writing) late 2026. If you are a U.S. resident, you can fight to protect the roadless rule by calling your representatives, using the information found in the link here.

Force Main Discharge Elevation

Force Main Discharge Elevation

Force Main Discharge Elevation

07/21/26

“How can we quantify the height a force main must pump to?”

Force mains pump wastewater to overcome elevational or frictional differences. The height they must pump to is called the Force Main Discharge Elevation. Wastewater does not need pumping to move once it reaches the force main discharge elevation since it will go downhill with gravity. The force main discharge elevation does not need to be above the pump inlet since the pump might be present to work against frictional losses only.

Force Mains

Force Mains

Force Mains

07/20/26

“What’s so special about pipes that carry wastewater using a pump?”

It’s typical for sewers to carry wastewater using gravity. However, sometimes the sewer needs to carry wastewater against gravity using pumps. Pipes that carry wastewater using pumps are called Force Mains. Force mains are typically filled due to pressurization.