Wood splintered, screws flew and columns sheared off from their bases when a series of earthquakes shook the UCLA campus last week.

Scale models of college dormitories were put to the seismic test in an earthquake simulator when seven teams from California universities competed in the seismic-design challenge Friday during the 2006 Pacific Southwest Regional Conference of the American Society of Civil Engineers, hosted by the UCLA Henry Samueli School of Engineering and Applied Science.

While earthquake-safe building design and drawing up plans may be nothing new to civil engineering students, participants said the hands-on construction aspect of the challenge was not exactly second nature.

“We weren’t particularly adept at woodworking. ... It was a lot of trial and error,” said Jerry Lee, a fourth-year civil engineering student who designed UCLA’s entry.

He estimated that UCLA’s seismic-design team spent about 50 hours constructing their model.

Teams were asked to design a three-story scale model of a dormitory for UCLA Housing, according to cost and land-size limits for Housing’s master plan, which would guarantee four years of on-campus Housing to freshmen.

UCLA’s team incorporated three different types of earthquake reinforcement into their project, including brace frames to keep columns upright during the violent shaking, and shear walls which stiffen the structure as a whole, Lee said.

Another element UCLA’s team used were moment frames which are “stiff connections” that make the scale-model dormitory move and absorb force as one, rather than act as a series of walls and columns put together but still functioning independently.

Designing an earthquake-safe building is about finding the right balance between strength and flexibility.

“Rigidity is not always good in seismic zones because it invites more resistance at each point,” said Mike Thompson, a fifth-year civil engineering student from California Polytechnic State University, Pomona.

Cal Poly Pomona’s entry included elements similar to those employed by UCLA and many other teams in the competition: shear walls, brace frames and moment-resisting connections.

The dorms were subjected to three quakes. The first was an earthquake of small size where only minor damage is acceptable as buildings are expected to be immediately reoccupied and fully operational after the earthquake.

The second test replicated the shaking patterns of the Northridge earthquake, a 6.7 magnitude tremor that struck Los Angeles in 1994, causing damage at UCLA.

Models were designed to be “life safe” in the second phase, according to the design scenario, which would allow occupants time to exit safely; heavy damage is acceptable as long as the building does not collapse.

The third optional test, known as “shake it to break it” among attendees, involved shaking the model dormitory until it began to break apart.

Most entries withstood 1-2 Gs of force before failing. When the structural columns dramatically sheared off from the base at this point on San Diego State University’s entry, the earthquake simulator’s operators quickly turned off the shake table before the dorm split in two and crashed into the crowd, much to the disappointment of the audience who was rooting for its destruction.

Other entries, such as that of the team from Cal Poly Pomona, put the shake lab to the test; its heavily damaged structure went through several full-force charges from the earthquake simulator, subjecting it to forces of up to 10 Gs, without producing audience-pleasing levels of destruction.

The shake table, powered by hydraulic pumps, can only create horizontal motion patterns, according to Robert Keowen, a senior development engineer in UCLA’s Department of Civil and Environmental Engineering.

The winning entry was built by the team from UC San Diego. Entries were judged on three criteria: weight; total story drift, which is the displacement at the top of the building relative to the bottom; and the ratio of acceleration from the top of the building to the bottom.

Participants said the seismic-design competition, along with the many others taking place at the conference, allowed them to exercise their theoretic knowledge in realistic scenarios.

“In class, you’re just doing a bunch of math, analyzing this and that. ... When you build it, you actually see what exactly is going on,” Lee said.