Guardrails for Use on Historic Bridges: Volume 1—Replacement Strategies

Bridges that are designated historic present a special challenge to bridge engineers whenever rehabilitation work or improvements are made to the bridges. Federal and state laws protect historically significant bridges, and railings on these bridges can be subject to protection because of the role they play in aesthetics. Unfortunately, original railings on historic bridges do not typically meet current crash-test requirements and typically do not meet current standards for railing height and size of permitted openings. The primary objective of this study is to develop strategies that can be used to address existing railings on historic bridges and to develop solutions that meet current design requirements. In addition to the modification, selection, and design of the bridge railing, the bridge deck is also impacted by changes made to the railing. Due to increased force levels recently required by AASHTO, deck overhangs require significantly more reinforcement than for past practice. These increases are being realized on all bridge decks and may pose particular challenges for the attachment of railing to historic bridges. Therefore, a secondary objective of this project is to investigate the design of the deck overhang and determine whether reduced amounts of reinforcement are possible. For Volume 1 (Replacement Strategies), three phases of research were conducted. First, an overview of current practice for addressing historic bridge railings was performed. Second, an investigation was conducted to document historic bridge railings in Indiana. Finally, rehabilitation solutions were developed to address the specific bridge railings found in Indiana. Based on this research, three retrofit strategies were developed which include an inboard railing, curb railing, and a simulated historic railing. These rehabilitation solutions can be used to address historic bridge railings not only in Indiana, but across the country. For Volume 2 (Bridge Deck Overhang Design), experimental testing of half-scale and full-scale overhang specimens was conducted, and the results were analyzed. Failures of in-service bridge railings were also evaluated. Based on this research, recommendations are provided for the more efficient and economic design of bridge deck overhangs. These recommendations are applicable not only for historic bridges, but for all concrete bridge decks

Improving the Design of U-Beams for Indiana

The use of prestressed U-beams, developed as an economical and aesthetic alternative to traditional I-beams, is becoming increasingly common. While U-beams are seeing increased use, questions have arisen in the design of bridges utilizing this girder type. Specific issues include live load distribution, bridge deck behavior, and debonding limits. First, since the U-beam is a new girder type, limited guidance exists for the live load distributions to be used in design. Second, due to the increased stiffness and strength of this girder, fewer girder lines are required resulting in increased deck spans. Finally, current AASHTO debonding limits severely restrict the efficiency and economy of the section. The objective of this research program is to develop design strategies to improve the efficiency and optimize the design of the Indiana modified U-beam with a focus on the concerns related to the design of U-beams. In particular, this research program will evaluate the live load distribution appropriate for the design of U-beams, assess the behavior and design of the bridge deck when supported by U-beams, and evaluate both the shear strength and shear design of the composite U-beam system. It is important that the strength strength of pretensioned concrete beams with debonded strand be fully evaluated. Five phases of research were conducted. The first phase consisted of evaluation of a U-beam bridge constructed in Indianapolis, Indiana to assess the live load distribution factors and flexural deck behavior of this bridge. The second phase evaluated the effectiveness of debonding sheathing to ensure that proper debonding is being achieved. The third phase evaluated the influence of the percentage of debonded strands on shear strength using rectangular and I-shaped cross sections to investigate flexure-shear and web-shear strengths, respectively. While this phase concentrated on the shear strength resisted by the concrete, the influence of transverse reinforcement was also evaluated. The fourth phase evaluated the influence of varying strength concretes, which are commonly used in composite sections, on shear strength. Finally, the fifth phase evaluated the shear strength of a 50% debonded U-beam both with and without transverse reinforcement. From the results, an improved understanding of the influence of debonding on shear strength is obtained. Recommendations are provided to improve the analysis, design, and construction of U-beams as well as the design and construction of girders utilizing debonded strand in general

Image Analysis of Pellet Size for a Control System in Industrial Feed Production

When producing aquaculture fish feed pellets, the size of the output product is of immense importance. As the production method cannot produce pellets of constant and uniform size using constant machine settings, there is a demand for size control. Fish fed with feed pellets of improper size are prone to not grow as expected, which is undesirable to the aquaculture industry. In this paper an image analysis method is proposed for automatic size-monitoring of pellets. This is called granulometry and the method used here is based on the mathematical morphological opening operation. In the proposed method, no image object segmentation is needed. The results show that it is possible to extract a general size distribution from an image of piled disordered pellets representing both length and diameter of the pellets in combination as an area

Multispectral Imaging for Determination of Astaxanthin Concentration in Salmonids

Multispectral imaging has been evaluated for characterization of the concentration of a specific cartenoid pigment; astaxanthin. 59 fillets of rainbow trout, Oncorhynchus mykiss, were filleted and imaged using a rapid multispectral imaging device for quantitative analysis. The multispectral imaging device captures reflection properties in 19 distinct wavelength bands, prior to determination of the true concentration of astaxanthin. The samples ranged from 0.20 to 4.34 g per g fish. A PLSR model was calibrated to predict astaxanthin concentration from novel images, and showed good results with a RMSEP of 0.27. For comparison a similar model were built for normal color images, which yielded a RMSEP of 0.45. The acquisition speed of the multispectral imaging system and the accuracy of the PLSR model obtained suggest this method as a promising technique for rapid in-line estimation of astaxanthin concentration in rainbow trout fillets

Farber disease: clinical presentation, pathogenesis and a new approach to treatment

<p>Abstract</p> <p>Background</p> <p>Farber Disease is an autosomal-recessively inherited, lysosomal storage disorder caused by acid ceramidase deficiency and associated with distinct clinical phenotypes. Children with significant neurological involvement usually die early in infancy, whereas patients without or only mild neurological findings suffer from progressive joint deformation and contractures, subcutaneous nodules, inflammatory, periarticular granulomas, a hoarse voice and finally respiratory insufficiency caused by granuloma formation in the respiratory tract and interstitial pneumonitis leading to death in the third or fourth decade of live. As the inflammatory component of this disorder is caused by some kind of leukocyte dysregulation, allogeneic hematopoietic stem cell transplantation can restore a healthy immune system and thus may provide a curative option in Farber Disease patients without neurological involvement. Previous stem cell transplantations in two children with severe neurological involvement had resulted in a disappointing outcome, as both patients died of progressive deterioration of their neurological status. As a consequence, stem cell transplantation does not appear to be able to abolish or even reduce the neurotoxic effects of the abundant ceramide storage in the brain.</p> <p>Methods</p> <p>After myeloablative, busulfan-based preparative regimens, four Farber Disease patients without neurological involvement received an allogeneic hematopoietic stem cell transplantation from related and unrelated donors. Stem cell source was BM in three patients and PBSC in one patient; GvHD-prophylaxis consisted of CsA and short course MTX.</p> <p>Results and discussion</p> <p>In all patients, HSCT resulted in almost complete resolution of granulomas and joint contractures, considerable improvement of mobility and joint motility without relevant therapy-related morbidities. All patients are alive and well at this point with stabile donor cell chimerism and without evidence of chronic GvHD or other late sequelae of stem cell transplantation.</p> <p>Conclusion</p> <p>Allogeneic hematopoietic stem cell transplantation provides a promising approach for Farber Disease patients without neurological involvement.</p