   |
| College & Team Information | |||
| College or University: | Student Chapter: | ||
| Address: | |||
| Phone: | Fax: | E-mail: | |
| Website address: | Faculty Advisor: | ||
| Person In Charge of Project: | |||
| Team Member | Class | Team Member | Class |
| Hours spent on project: | Cost of Material ($ Amount) | ||
| Student: | Faculty: | Donated: | Purchased: |
| 1. Abstract - (Max 500 word narrative) | ||
| The design concept for the 2004 Timber Bridge Competition submitted by the Student Chapter of the Forest Products Society at Virginia Tech utilizes an almost completely metal free design. The only place metal fasteners were used was to attach the trusses to the deck and for attaching splices to the wood I-joists. For the other connections in the timber bridge (deck, and upper trusses) black locust wood dowels were used. The Miller Dowel Company of Winnetka, IL donated a combination of 1x and 2x dowels to the project. | ||
| 2. Deflection Table | ||||||
| Deflection (millimeters - rounded to 2 decimal places) | ||||||
| Loading Inc. | Bridge | Beam L | Beam R | Average (L&R) | Gross Deck | Net Deck |
| 5 kN | ||||||
| 10 kN | ||||||
| 15 kN | ||||||
| 20 kN - 0 min. | ||||||
| 20 kN - 15 min. | ||||||
| 20 kN - 30 min. | ||||||
| 20 kN - 45 min. | ||||||
| 20 kN - 60 min. | ||||||
| 1) Loading Increments. | ||||||
| 2) Bridge - As measured at midspan of the longitudinal beam receiving greatest loading. | ||||||
| 3) Beam L - As measured under the longitudinal beam to left of selected deck monitoring point. | ||||||
| 4) Beam R - As measured under the longitudinal beam to right of selected deck monitoring point. | ||||||
| 5) Average (L&R) - Average of 3 and 4. | ||||||
| 6) Gross Deck - As measured under the loading point expected to experience maximum deflection. | ||||||
| 7) Net Deck - Column 6 minus column 5. | ||||||
| Deck span (transverse distance between main longitudinal bridge support members measured from inside edge to inside edge) = mm / 100 = mm (max. allowable net deck deflection) | ||||||
| 3. Materials List | |
| Material Item | Weight (kg) |
| Total Weight (Kg) | |
| Weight Non-wood (Kg) | |
| Percent Non-wood | |
| 4. Summary -Describe Bridge and behavior under load - (Max 500 words) | ||
| The performance requirements for the competition dictated that the bridge must be able to carry 20 kN for one hour and deflect no more than 10 mm under this sustained load. The deck deflection was required to be less than 4.826 mm (deck span/100) during the loading. In order to measure the bridge and deck deflections, 3 dial gauges were used. Two dial gauges were placed midspan on the inner two most longitudinal members. These two dial gauges were used to calculate an average value for the “Bridge deflection”. Individually these dial gauges were used for the “Beam L.” and Beam R.” measurements. One dial gauge was placed at midspan under one deck panel. This dial gauge was used to measure “Gross deck deflection”. The load was distributed to the bridge by attaching loading blocks to a pallet and placing weight inside of a plywood box. The loading blocks were 90mm x 60mm in dimension. A combination of 50 lbs lead blocks and 25lb bags of lead shot were placed into the box resting on the pallet in order to achieve the 20 kN load. The base plate for the bridge consisted of one board 31mm in width and 38mm in height nailed to the bottom of the vertical supports on each end of the bridge. The maximum “Bridge deflection” reached was 10.49 mm. The maximum “Net deck deflection” measurement was 3.89 mm. | ||
| 5. Project Drawings and Photos | ||||
 |
 |
 |
 |
 |
| Longitudinal Cross Section | Tranverse Cross Section | Trimetric View | Project Photo | Team Photo |
| Click on drawing or photo above for larger view. | ||||
| 6. Component Details | ||
| In ten (10) words or less per each component below, describe the bridge: | ||
| Stringers/Girders: | 14" I-beams with osb webbing glued and splice back together | Deck: | 1 inch x 51/2 inch 5 foot ACQ treated deck boards |
| Floor Beams: | ||
| Suspension: | A-frame design composed of 146 mm x 38.1 mm boards | |
| Unique: | ||
| Describe preservative treatment for all wood members. Include type and concentrations. Also include a short statement of why this treatment was selected. Did the treatment requirement present any special problems? If yes, provide details | ||
| The I-joists were treated with ACQ by a local treating facility to a concentration of 0.4. The deck boards were commercially treated with ACQ to a concentration of 0.4. The remaining boards were commercially treated with CCA to a concentration of 0.4. | ||
| 7. Special Considerations | ||
COPYRIGHT ©2009 - MSRCD
Programming by:Keith Mazer
All rights reserved.