SYLMAR : Professor Evaluates Earthquake Damage

Engineers should have more hands-on involvement during construction of buildings to safeguard against structural damage caused by earthquakes.

That’s one of several recommendations being discussed by a city subcommittee charged with evaluating structural damage wreaked by the Northridge earthquake in hillside regions of Los Angeles, said Leon A. Risemberg, associate professor of engineering at Mission College.

Risemberg is among several engineering consultants recent appointed to the subcommittee.

The group’s recommendations will be submitted to the Los Angeles Department of Building and Safety in a few weeks and could lead to changes in building codes and how the codes are enforced.

Risemberg, an Argentine native who lives in Van Nuys, has been a consulting structural engineer for more than 40 years. He began Mission’s engineering program, which transfers students to four-year colleges, in 1988.

Over the last three weeks, Risemberg has donated his spare time--and considerable engineering expertise--to check out buildings that have been red- or yellow-tagged as a result of the quake. He’s also inspected buildings left intact to compare construction materials and design to those damaged. Working with another subcommittee member, Risemberg has inspected about a dozen buildings.

The subcommittee’s findings have, so far, revealed a few surprises, Risemberg said.

Most of the hillside buildings he’s inspected have been structurally sound--surprising considering that some of the buildings seem precariously perched on stilt frames jutting out over hills.

“We’ve been investigating the sub-structures of some of the buildings in hillside areas condemned as structurally unsafe following the quake--buildings that are generally lighter, supported high up by cross-bracing,” Risemberg said. “We’ve found that few of these buildings in the hills had structural problems, compared to others located lower down.”

Risemberg said that in those buildings where structural damage was discovered, the problem was more with “the construction, not the design of the building. We have to make sure the engineers go out and see how the buildings are being built.”