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Full-Text Articles in Engineering
Field And Numerical Study For Deteriorating Precast Double-Tee Girder Bridges, Brian Kidd
Field And Numerical Study For Deteriorating Precast Double-Tee Girder Bridges, Brian Kidd
Electronic Theses and Dissertations
Two deteriorating DT bridges in South Dakota, both over 30-years old, were field tested with a static and dynamic load. From the recorded strain values, the liveload distribution factors (LLDFs) and dynamic load allowance (IM) factors were calculated. The AASHTO LRFD and AASHTO Standard Specifications were compared with the field LLDFs and IMs. It was determined that the AASHTO LRFD Specifications were conservative for deteriorating DT girder bridges, with two exceptions. The AASHTO Standard codified LLDFs were significantly higher than the field LLDFs in all cases. The AASHTO LRFD and AASHTO Standard specifications were conservative when calculating the IM factors …
Repairable Moment-Resisting Steel Buildings, Heath William Pederson
Repairable Moment-Resisting Steel Buildings, Heath William Pederson
Electronic Theses and Dissertations
Current seismic design codes ensure life safety for buildings, but structural members may significantly yield or even fail under strong earthquakes. A new design approach is to implement connections that localize the yielding and failure to fuses. A more sophisticated approach is to be able to replace the fuses after the event. The present study was carried out to develop repairable moment-resisting (MR) connections for steel buildings and to investigate their seismic performance through nonlinear finite element analyses (FEA). Two details were proposed using buckling restrained fuses (BRFs) and buckling restrained reinforcement (BRR). Test data was collected from the literature …
Escherichia Coli Removal From Stormwater Using Steel Chips Filter, Peng Dai
Escherichia Coli Removal From Stormwater Using Steel Chips Filter, Peng Dai
Electronic Theses and Dissertations
Media filtration has received increasing attention as an effective technology that can facilitate the removal of particles and dissolved pollutions in the stormwater. However, most traditional media filtration systems are generally ineffective in removing bacteria, causing pollution of groundwater and receiving surface water. In this study, recycled steel chips were evaluated as low-cost filter materials for bacterial removal from stormwater. Laboratory column experiments were conducted to evaluate the impact of steel chips particle size, flow rate, initial E.coli concentration, pH, natural organic matter (NOM), steady and intermittent flow on E.coli removal. The results showed that E.coli removal decreased from 99.4% …