Sustaining the commons
We’ve discussed the tragedy of the commons, an economic theory that dates back to Aristotle: “What is common to the greatest number has the least care bestowed upon it.” It […]
Author: Rachel Detwiler
Horses, not zebras
“When you hear hoofbeats, think horses, not zebras.”—Theodore Woodward, University of Maryland School of Medicine Although this advice originated in medicine, it applies equally well to forensic engineering: Look for […]
What engineers should know about acceptance testing
At the ACI spring convention, the Hot Topic session focused on acceptance testing of concrete. Someone pointed out that we’ve been having the same discussion for the last 40 years. […]
Choose your battles
For 19 years I had an orange tabby, known formally as Fridtjof den dristige*, who defended our territory as only an orange tabby can. Orange tabbies have a reputation as […]
Diagnosing scaled concrete flatwork
Exterior concrete flatwork in a freezing climate experiences the most severe freeze-thaw concrete exposure class, F3. It undergoes cycles of freezing and thawing in the presence of water and deicing […]
Delayed ettringite formation
A few weeks ago I participated in a webinar about mass concrete and thermal control plans. I was dismayed to hear the presenter cite delayed ettringite formation as the reason […]
Troubleshooting concrete on the jobsite
Heidi Lukkarila, Beton’s field technician, has many years’ experience troubleshooting concrete on the jobsite. Troubleshooting requires the ability to think on your feet, as time is always of the essence. […]
The value of failure
A few weeks ago I met with a student team to coach them on their final report for their senior design project. The students were discouraged because they’d spent two […]
Concrete acceptance testing
Concrete acceptance testing refers to the testing of concrete sampled directly from the ready mixed concrete truck. Its purpose is to verify the compressive strength of the material as delivered […]