Corrugated wood composite panels for structural decking

High flexural strength and stiffness can be achieved by forming a thin panel into a wave shape perpendicular to the bending direction. The use of corrugated shapes to gain flexural strength and stiffness is common in metal and reinforced plastic products. However, there is no commercial production of corrugated wood composite panels. This research focuses on the application of corrugated shapes to wood strand composite panels. Beam theory, classical plate theory and finite element models were used to analyze the bending behavior of corrugated panels. The most promising shallow corrugated panel configuration was identified based on structural performance and compatibility with construction practices. The corrugation profile selected has a wavelength equal to 8”, a channel depth equal to ¾”, a sidewall angle equal to 45 degrees and a panel thickness equal to 3/8”. 16”x16” panels were produced using random mats and 3-layer aligned mats with surface flakes parallel to the channels. Strong axis and weak axis bending tests were conducted. The test results indicate that flake orientation has little effect on the strong axis bending stiffness. The 3/8” thick random mat corrugated panels exhibit bending stiffness (400,000 lbs-in2/ft) and bending strength (3,000 in-lbs/ft) higher than 23/32” or 3/4” thick APA Rated Sturd-I-Floor with a 24” o.c. span rating. Shear and bearing test results show that the corrugated panel can withstand more than 50 psf of uniform load at 48” joist spacings. Molding trials on 16”x16” panels provided data for full size panel production. Full size 4’x8’ shallow corrugated panels were produced with only minor changes to the current oriented strandboard manufacturing process. Panel testing was done to simulate floor loading during construction, without a top underlayment layer, and during occupancy, with an underlayment over the panel to form a composite deck. Flexural tests were performed in single-span and two-span bending with line loads applied at mid-span. The average strong axis bending stiffness and bending strength of the full size corrugated panels (without the underlayment) were over 400,000 lbs-in2/ft and 3,000 in-lbs/ft, respectively. The composite deck system, which consisted of an OSB sheathing (15/32” thick) nailed-glued (using 3d ringshank nails and AFG-01 subfloor adhesive) to the corrugated subfloor achieved about 60% of the full composite stiffness resulting in about 3 times the bending stiffness of the corrugated subfloor (1,250,000 lbs-in2/ft). Based on the LRFD design criteria, the corrugated composite floor system can carry 40 psf of unfactored uniform loads, limited by the L/480 deflection limit state, at 48” joist spacings. Four 10-ft long composite T-beam specimens were built and tested for the composite action and the load sharing between a 24” wide corrugated deck system and the supporting I-joist. The average bending stiffness of the composite T-beam was 1.6 times higher than the bending stiffness of the I-joist. A 8-ft x 12-ft mock up floor was built to evaluate construction procedures. The assembly of the composite floor system is relatively simple. The corrugated composite floor system might be able to offset the cheaper labor costs of the single-layer Sturd-IFloor through the material savings. However, no conclusive result can be drawn, in terms of the construction costs, at this point without an in depth cost analysis of the two systems. The shallow corrugated composite floor system might be a potential alternative to the Sturd-I-Floor in the near future because of the excellent flexural stiffness provided.

Exhibits

The Finnish American Heritage Center at Finlandia University recently installed three exhibits. They include a photographic exhibit titled “Rural Reflections: Finnish American Buildings and Landscapes in Michigan’s Copper Country”; a historic photography exhibit named “People, Place and Time: Michigan’s Copper Country Through the Lens of J.W. Nara”; and a pair of lithographs acquired by the National Park Service which were on either side of the Italian Hall stage the night of the infamous Christmas Eve tragedy 100 years ago. The “Rural Reflections” exhibit documents the built environment that Finnish immigrants and their descendants created in Michigan's Copper Country from the 1880s through the 1930s. Although much of this heritage has been lost with the passage of time, the district yet holds one of the largest concentrations of rural Finnish buildings and cultural landscapes in North America. The Nara exhibit, funded in part by descendants Robert and Ruth Nara of Bootjack Michigan, works from historical photographs held at the Michigan Tech Archives. Interpretive panels highlight the people, places, and times that J.W. Nara experienced during his lifetime and include material on urban life, farming, and the 1913 Michigan copper miners’ strike. The lithographs are a recent and unique acquisition for the Keweenaw National Historical Park, and will be on protected display at the FAHC. One of the panels shows the Italian royal family and was produced in 1908, while the other, produced in 1905, is of the five founders of the modern Italian state. For more information about the exhibits at the Finnish American Heritage Center, call (906) 487-7302.

Exhibits

The Finnish American Heritage Center at Finlandia University recently installed three exhibits. They include a photographic exhibit titled “Rural Reflections: Finnish American Buildings and Landscapes in Michigan’s Copper Country”; a historic photography exhibit named “People, Place and Time: Michigan’s Copper Country Through the Lens of J.W. Nara”; and a pair of lithographs acquired by the National Park Service which were on either side of the Italian Hall stage the night of the infamous Christmas Eve tragedy 100 years ago. The “Rural Reflections” exhibit documents the built environment that Finnish immigrants and their descendants created in Michigan's Copper Country from the 1880s through the 1930s. Although much of this heritage has been lost with the passage of time, the district yet holds one of the largest concentrations of rural Finnish buildings and cultural landscapes in North America. The Nara exhibit, funded in part by descendants Robert and Ruth Nara of Bootjack Michigan, works from historical photographs held at the Michigan Tech Archives. Interpretive panels highlight the people, places, and times that J.W. Nara experienced during his lifetime and include material on urban life, farming, and the 1913 Michigan copper miners’ strike. The lithographs are a recent and unique acquisition for the Keweenaw National Historical Park, and will be on protected display at the FAHC. One of the panels shows the Italian royal family and was produced in 1908, while the other, produced in 1905, is of the five founders of the modern Italian state. For more information about the exhibits at the Finnish American Heritage Center, call (906) 487-7302.

Exhibits

The Finnish American Heritage Center at Finlandia University recently installed three exhibits. They include a photographic exhibit titled “Rural Reflections: Finnish American Buildings and Landscapes in Michigan’s Copper Country”; a historic photography exhibit named “People, Place and Time: Michigan’s Copper Country Through the Lens of J.W. Nara”; and a pair of lithographs acquired by the National Park Service which were on either side of the Italian Hall stage the night of the infamous Christmas Eve tragedy 100 years ago. The “Rural Reflections” exhibit documents the built environment that Finnish immigrants and their descendants created in Michigan's Copper Country from the 1880s through the 1930s. Although much of this heritage has been lost with the passage of time, the district yet holds one of the largest concentrations of rural Finnish buildings and cultural landscapes in North America. The Nara exhibit, funded in part by descendants Robert and Ruth Nara of Bootjack Michigan, works from historical photographs held at the Michigan Tech Archives. Interpretive panels highlight the people, places, and times that J.W. Nara experienced during his lifetime and include material on urban life, farming, and the 1913 Michigan copper miners’ strike. The lithographs are a recent and unique acquisition for the Keweenaw National Historical Park, and will be on protected display at the FAHC. One of the panels shows the Italian royal family and was produced in 1908, while the other, produced in 1905, is of the five founders of the modern Italian state. For more information about the exhibits at the Finnish American Heritage Center, call (906) 487-7302.

Sustainability study of nanomaterials including societal and occupational implications

In recent years there has been a tremendous amount of research in the area of nanotechnology. History tells us that the commercialization of technologies will always be accompanied by both positive and negative effects for society and the environment. Products containing nanomaterials are already available in the market, and yet there is still not much information regarding the potential negative effects that these products may cause. The work presented in this dissertation describes a holistic approach to address different dimensions of nanotechnology sustainability. Life cycle analysis (LCA) was used to study the potential usage of polyethylene filled with nanomaterials to manufacture automobile body panels. Results showed that the nanocomposite does not provide an environmental benefit over traditional steel panels. A new methodology based on design of experiments (DOE) techniques, coupled with LCA, was implemented to investigate the impact of inventory uncertainties. Results showed that data variability does not have a significant effect on the prediction of the environmental impacts. Material profiles for input materials did have a highly significant effect on the overall impact. Energy consumption and material characterization were identified as two mainstreams where additional research is needed in order to predict the overall impact of nanomaterials more effectively. A study was undertaken to gain insights into the behavior of small particles in contact with a surface exposed to air flow to determine particle lift-off from the surface. A mapping strategy was implemented that allows for the identification of conditions for particle liftoff based on particle size and separation distance from the wall. Main results showed that particles smaller than 0:1mm will not become airborne under shear flow unless the separation distance is greater than 15 nm. Results may be used to minimize exposure to airborne materials. Societal implications that may occur in the workplace were researched. This research task explored different topics including health, ethics, and worker perception with the aim of identifying the base knowledge available in the literature. Recommendations are given for different scenarios to describe how workers and employers could minimize the unwanted effects of nanotechnology production.