Sometimes it’s nice just to appreciate where the structures are being built.
Wildcat Road Bridge - Livingston County, NY
(Note: the following is reprinted with permission from the engineering firm, C & S Companies. This particular structure was designed out of their Rochester office for Livingston County, New York. . Visit http://www.cscos.com or call (585) 325-9040 for further information.)
C&S designed a replacement to the historic Wildcat Road bridge over Wildcat Gully, which received an ACEC New York Platinum Award for Engineering Excellence and an APWA–Monroe County/Genesee Valley Branch Structures Project of the Year award. The steel Pratt Truss bridge was built in 1910, and had been closed to traffic for nearly a decade. It was initially scoped and budgeted for rehabilitation. Because it was a historic structure, C&S provided sound engineering arguments to SHPO for replacement, proving that rehabilitation was not an option. The challenge was to design a superstructure with adequate strength, while ensuring the stability of the foundations on the erodible shale streambanks, all within a budget set for rehabilitation only. The existing 88-foot, single-lane truss was replaced with a 100-foot, steel superstructure with timber decking. Perched abutments were founded on drilled shafts to address the erodible shale concerns. While traffic volumes justified a one-lane bridge, the clear width was doubled to 20 feet to allow access for large farming equipment.
One of Laminated Concepts' latest projects is the supply of a 50' x 30' glued laminated timber stringer bridge structure to Buchanan County, Iowa. The County will be using their own crews to demolish, and construct the new bridge on GRS abutments. The interesting thing about this project is that it is being partially funded with the assistance of the Federal Highway and the National Center for Wood Transportation Structures. (http://www.woodcenter.org)
The folks in Iowa will be installing sensors in both the abutments and bridge superstructure to record several performance parameters used to evaluate and understand the behavior of all the parts of the GRS-IBS abutments and bridge superstructure.
AND, they invite you to watch. The complete construction process is being monitored and is available to watch on the NCWTS's website (http://www.woodcenter.org/bec_cam/).
We would like for you to watch the process and as always, if you have any questions or comments, feel free to contact us.
We were sent an email today (containing an article posted below) about the use of timber as a building material for large commercial buildings . The article was originally posted in the Fall 2015 issue of Construction Data Quarterly. Although this idea has been in the works for a few years now, I was impressed reading it. Then and now.
The advancements in timber or should I say the advancements in engineered timber design and manufacturing, are securing a spot for this construction material in the Country’s infrastructure. It's also one of the few products that can truly boast entirely made in the USA. With its low carbon footprint, renewable, managed supply chains and competitive pricing, timber will shine as its introduction into the larger commercial building structures. Something that those of us involved with engineered timber highway structures….bridges….have known all along.
Towering Timber: Will Future Skyscrapers Be Made Of Wood?
Posted on March 18, 2016 by Kendall Jones+ in Construction News
- BRIDGE PROBLEM & CRITERIA:
- 1 week maximum road closure from demolition to opening for traffic
- 2 day maximum bridge superstructure construction schedule
- LRFD HL93 loadings, Crash Tested Guide Railings and meeting the hydraulics of the existing superstructure.
- Pre fabricated, Stress Laminated Glu Lam Deck.
For a County in New Jersey that is exactly what was chosen for this 42'-0 bridge span. The bridge utilizes treated glued laminated beams placed side by side with field installed transverse stressing rods, stressed to a predetermined level. Using stressed beams instead of systems like a stringer bridge with transverse deck, allow the depth of structure to be kept to a minimum, matching the previous structures depth.
The bridge is designed with a 10° skew to align with the stream profile. Stress laminated decks require that the stressing rods are placed perpendicular to the bridge structure. Each beam had to have different fabrication performed due to them being offset from the adjacent beams.
All the holes were predrilled at the plant prior to pressure treatment.
Within the first day, all beams were set and aligned. The high strength rods were installed then stressed.
The second day was left to assemble the Crash Tested guide railing and anchor the bridge to the concrete abutments.