The Lincoln Memorial provides a clear example of how the human impact of well-done geotechnical engineering often exceeds even the most noteworthy technical merit.  The building of a memorial to honor President Lincoln was first suggested a few years after his assassination but only gained traction in the early 1900s once the divisions of the Civil War had partly cooled.  The project site, chosen after a decade of quintessential Washington jousting, consisted of material dredged from the Potomac River.  The project’s geotechnical feats included building the Memorial upon reinforced concrete-filled steel pipe piles and constructing the Reflecting and Rainbow Pools by excavating 135,000 yd3 of soil, installing an extensive underdrainage system, and driving hundreds of reinforced concrete piles.  The early 21st century has seen several geotechnical renovations and improvements to the site.
The Memorial’s 1922 dedication featured presidential son Robert Todd Lincoln as its guest of honor and focused on the elder Lincoln’s greatness in reuniting the country.  The view was politically palatable during an era when segregation was an abhorrent fact of US life, including in Washington, DC.  However, the popular meaning of the Memorial slowly changed over the following decades as more Americans came to believe their government should protect the civil rights of citizens of all races.  The Memorial served as a backdrop for two key events in this transformation – Marian Anderson’s 1939 Easter concert and Martin Luther King’s 1963 “I Have a Dream” address.  Today, Americans recognize that Lincoln’s greatness stems from his successful championing of abolition, and the Memorial played a key role in this sea change.

Michael Bennett, P.E., is a geotechnical PhD student at Virginia Tech working with Prof. Alba Yerro on modeling the deformation of subgrade soil beneath temporary roadways. He spent 6 years in practice, primarily working on transportation infrastructure projects. Michael earned a BS in Civil Engineering and BA in History from Lafayette College and a geotechnical MS from VT. He also authors the Geotechnical History Blog for ASCE’s Geo-Institute.