Although 80 years and 1,600 miles apart, two deadly structural failures—one involving molasses and steel, and the other fire and logs—confirmed that inattention to detail is never inconsequential when it comes to disastrous construction blunders. The collapse of each structure (both were approximately five-stories high) was so extrao dinary that it made headline news around the world.

These two incidents had several crucial similarities. Both large structures evolved from smaller ones and were built without direct oversight by a registered professional engineer (P.E.) educated in structural design and construction. For one doomed configuration, no structural drawings were ever prepared. For the other, d rawings were not signed or stamped by a qualified professional engineer.

The builders on both projects failed to submit P.E.-stamped structural design calculations to building officials before construction.

Even though the public’s health, welfare, and safety were at risk in these cases, the people in charge did not engage an experienced, professional engineer to assist them during design or construction. After both collapses, however, costly and protracted investigations and lawsuits demanded that many professional engineers were engaged by the litigants’ lawyers to serve as expert witnesses.

The first case—the Great Boston Molasses Flood of 1919—involved the collapse of a steel tank holding 12,000 tons of molasses. On a mild winter day in January, the sides of the massive tank suddenly burst.

The sound of rivets popping and plates shearing simulated machine-gun fire. It released a deadly, 15-foot-high, 120-foot-wide tidal wave of thick, brown, sticky liquid. The gooey mess exploded so quickly that it crushed or swall owed everything in its path, including school children at a nearby playground.

Days later, one man, along with his horse and wagon, was found frozen in motion, embedded in a mass of molasses. In total, 21 men, women, and children died (some by drowning) and more than 150 were injured.

Several horses died and much property was destroyed or severely damaged, i n cluding an adjacent elevated public rail line. The resulting lawsuits, w h i ch took nearly six years and more than 3,000 witnesses to settle, produced 40,000 pages of court records. Eventually, a total of 125 settlements worth nearly $1 million (in 1925 dollars) were reached.

In 1999, the damage and fatalities caused by the Texas A&M Bonfire tragedy were equally stunning. More than 50 percent of the people (mostly college students) working near the colossal log structure when it collapsed (during erection) were killed or injured. In total, 12 people died and 27 were injured after some 7,000 telephone-pole-size logs smashed into a massive junk heap.

Building the bonfire was a tradition that started in 1909 as a warm-up to the annual A&M and Texas football game. It began with the burning of a big pile of trash and grew into an increasingly large structure each year, always built "from memory " without construction drawings. The effort eventually took 5,000 students investing 125,000 work hours to complete. Since the disaster, lawsuits concerning the collapse remain open and ongoing—and no university-sanctioned bonfire has been built.

The real tragedy of the molasses tank and bonfire failures is knowing they could have been prevented if qualified structural engineers had been in charge.

The molasses catastrophe involved overstressing the bottom wall ring—one of seven, 7-foot-high circular pieces connected together with riveted lap splices, one on top of the other, to form the 50-foot-tall round tank. Under extreme tension, several secondary stresses also contributed to the structure’s ultimate fracture. These were induced by cutting and inadequately reinforcing a large manhole opening in the heavily stressed bottom ring wall; locating the vertical splice of the second ring directly over the top of the manhole; and under sizing riveted splice joints with no redundant capacity.

The wedding-cake-shaped timber bonfire tumbled because of several miscues, including having no tension cable around the tops of the bottom layer of logs; using inadequately sized wire to tie individual clusters of logs together; installing overly crooked logs requiring excessive wedging; and having too few logs overlapping between layers and extending into the ground.

These problems and omissions sure ly would have been caught if those in charge understood the significance of engineering and had hired licensed engineering experts to design and oversee construction.

How can the structural engineering community better inform decision-makers and the public of the wisdom to seek structural advice before something collapses? History tells a tragic story of what can happen when detailed precautions are not taken.

Richard Weingardt, P.E., is CEO and chairman of Richard Weingardt Consultants, Inc., a Denver-based structural engineering firm. He can be reached via e-mail at rweingardt@gostructural.com.