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, […]
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 […]
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 […]
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 […]
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 […]
Following last month’s power outage in Texas, state legislators conducted hearings to sort out what happened and why. There was plenty of finger-pointing and little enlightenment. Power company executives laid […]
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 […]
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 […]
Some of us who live in arid parts of the world think about water with a reverence others might find excessive.—Joan Didion, “Holy Water”, 1977 Most of us learned in […]
In Minnesota, Iowa, and South Dakota, we sometimes see aggregate popouts, particularly in concrete flatwork. Popouts are unsightly surface defects that may appear a few hours to a few weeks […]