What else can solar panels do?
We’ve all seen arrays of solar panels on rooftops. They convert the sun’s energy into electricity, lowering the homeowner’s electric bill—and maybe even adding power to the grid. On a […]
Insights
Sustainable building design in traditional architecture
Now that things are opening up again, I’m looking forward to traveling. One thing that interests me is local architecture, especially traditional architecture. Sometimes we can be rather snobbish about […]
Specifying tests for durable concrete
Throughout my career, our industry has been pursuing performance specifications for concrete. That is, we want specifications for what the concrete must do, not what it must be. The sticking […]
What is sulfate attack?
Concrete in certain environments is subject to sulfate attack. These include seawater, some industrial environments, sanitary sewers, and sulfate-bearing soils and groundwater. As engineers have known since the early 1900s, […]
Objectivity in technical writing
Part of professional engineering practice is objective communication. In fact, it’s so important that the Engineers’ Code of Ethics calls it out specifically. How do we achieve objectivity in technical […]
Eisenhower’s interstate highway system
Throughout the United States, many interstate highways carry the name “Eisenhower” to honor the president who promoted the concept. But Eisenhower’s interstate highway system is showing its age. President Biden […]
Hedonistic sustainability: sustainability can be fun
In the Middle Ages, alchemists sought in vain to turn base metals into gold. Now all that remains of alchemy is some laboratory equipment. But imaginative urban planning offers a […]
Comparing ASTM C1556 and NT Build 492
ASTM C1556 and NT Build 492 both measure the ease with which chloride ions migrate into concrete. Both test methods estimate the diffusion coefficient, a measure of the rate at […]
ASTM C1798 permits safe reuse of returned fresh concrete
CALGreen requires the reuse, recycling, or salvage of at least 65% of the waste from construction and demolition. A previous blog discussed how to reuse water from concrete production. Another […]
Concrete for slabs on ground
Although engineers usually think of compressive strength as the most important property of concrete, concrete for slabs on ground is different. According to ACI PRC-302.1-15, for slabs on ground the […]