Modern CMU construction almost always requires the installation of vertical reinforcement in the grouted cells of the CMU. However, addressing structural issues associated with unreinforced CMU construction prevalent prior to the 1990s can be daunting. In the author’s experience, today’s engineers do not know how to deal with, or adequately investigate, diagonal cracks in unreinforced CMU walls. …
Even before the tumultuous events of 2020, things were changing rapidly in our profession. The technological revolution, globalization, major societal challenges requiring structural engineering leadership, and the advancement of a new generation of engineers eager to make a difference in the world have been shifting the landscape for some time. …
Advances in construction technology create opportunities using new and innovative methods for the building construction industry, which are fast, efficient, reliable, and cost-effective. One of these methods is three-dimensional (3-D) printing construction technology (also known as additive manufacturing) for the job site construction of 3-D concrete structures. Although 3-D printing technology is not new and has been utilized for small-scale part production since the 1980s, it has found its way most recently into the construction industry and is pushing the boundaries of how engineers view and approach building construction. …
Conventional concrete parapets can form a thermal bridge that dissipates heat energy outside like large cooling fins, aided by cold winds whipping over the rooftop. One solution is to cast a structural thermal break between the parapet and the heated interior structure supporting it. …
This four-part series (Part 1, STRUCTURE, November 2019, Part 2, January 2020, Part 3, April 2020) discusses how the collapse of a building during a demolition operation in Philadelphia in 2013, which resulted in several fatalities, led to the enactment of a City Ordinance to prevent similar future calamities. …
Traditionally, the role of the structural engineer on building projects has focused on structure-related tasks – member sizing, connection detailing, general notes, and specifications for structural components. Design criteria such as fire-resistance ratings, acoustics, and aesthetics have primarily been the architect’s domain. …
On March 18th, 2020, a moderate earthquake of magnitude 5.7 hit Magna, Utah, at 7:09 am. In the downtown area, the strongest shaking lasted 4-6 seconds; however, the shaking was strong enough to be felt for about 20 seconds. For people living in high-rise buildings in downtown Salt Lake City, 17 miles from Magna, the shaking seemed to last much longer. Fortunately, due to the Covid-19 pandemic and the early hour at which the earthquake occurred, most people were still at home and in bed. The earthquake was reportedly felt as far away as 66-miles from the epicenter. …
High-rise residential concrete construction in South Florida typically consists of unbonded post-tensioned concrete slab construction. A key component to the durability of these slabs is the finishing of the stressing pockets for the post-tensioned tendons, which has proven to be problematic for contractors, especially in South Florida. Tendon finishing consists of cutting/greasing cable ends and capping and filling the pockets with grout. …
I taught Concrete Structures in the Architecture program at the Rhode Island School of Design (RISD) in the Spring 2020 semester. The course was envisioned by my predecessor and maintained by me as a technical and qualitative exploration of designing concrete, with a series of rigorous but practical design examples for different elements. The lectures included case studies of buildings, discussions of the theory behind concrete design, and sample problems solved on the chalkboards. …
Engineering is a profession based on truth and integrity. Firms and clients rely on an engineer’s expertise, and they trust their engineers to conduct themselves ethically. Unfortunately, we have seen first-hand where lapses in ethical judgment, resulting from project issues, cut short an accomplished career. These lapses usually come from otherwise decent and honest people, and their actions appear inexplicable. In many circumstances, those lapses can be traced to the same cause – conflict avoidance. …