by Web Editor | Jul 17, 2017 | News
A two-story cross-laminated timber (CLT) structure is being subjected to the forces produced by a 1994 6.7 Northridge earthquake. The engineered simulation is expected to reveal ways in which tall wood buildings could survive damaging earthquakes.
Workers constructed a 22-foot tall wood test structure on UC San Diego’s shake table, a device for shaking structural models or building components with a wide range of simulated ground motions, like earthquakes.
Led by the Colorado School of Mines (CSM), the new test will examine the viability of constructing quake-resistant CLT buildings that could be as tall as 20 stories high.
“We are working to minimize the amount of time buildings are out of service after large earthquakes,” CSM engineer Shiling Pei said in a statement. “We are also focused on cutting the costs required to repair them.”
Cross-laminated timber advocates say it can be used to construct buildings of equal strength and fire-resistance as those made of steel and concrete. It has also fueled the passions of architects and environmentalists, who believe it to be a much greener method for housing the world’s growing population.
From Woodworking Network: https://www.woodworkingnetwork.com/two-story-cross-laminated-timber-simulated-67-earthquake?ss=news,news,woodworking_industry_news,news,almanac_market_data,news,canadian_news
by Web Editor | Mar 13, 2017 | News
Building a house, garage or even a shed today isn’t as easy as going to the local lumberyard and buying whatever dimension of wood you need. A lot of emphasis goes into the grade of the wood and its stress and load ratings, according to Everett Brands, manager of Arrow Building Center in Glencoe. Arrow took over the former Fullerton Lumber Center on Desoto Avenue this past October.
Today, main structural pieces, such as headers, consist of LVL, or laminated veneer lumber, an engineered product typically of poplar, fir or pine. It is laminated under heat and pressure with a moisture-resistant resin and it’s stronger than typical native wood. Building codes call for the use of specific lumber grades for specific applications.
“Anything longer than six feet as a header has to be LVL,” Brands said. The LVL products range up to 36 or 48 feet long. While regular lumber could sag or bow under extreme weight, the LVL won’t. Thus LVL is typically used over windows and entries, especially with tall entries.
“We use a lot of engineered products — beams, headers and I-joists,” added Matt Smieja, manager of Simonson Lumber, just outside Hutchinson along State Highway 7 East.
Years ago, when forests were being cut for the first time, the wood tended to be of higher quality as far as grain and knots. But new stands of trees generated are of a lower grade.
From the Hutchinson Leader: https://www.crowrivermedia.com/hutchinsonleader/news/business/engineered-lumber-has-replaced-natural-lumber-in-most-key-building/article_67ee0dc7-e4d8-56c8-932e-9ca668bb40bc.html
