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Thermally induced stresses can build up in rigid pavements without pressure relief joints. The pressure created becomes a problem for adjacent structures such as bridges. The pressure can cause the pavement to push on the bridge and close the bridge expansion joints. This sets the stage for additional distress if not repaired quickly. This paper presents a case study where excessive pavement pressure damaged a two-span conventional bridge spanning Interstate 35 in Moore, Oklahoma. The bridge was instrumented with vibrating wire sensors to gather information on the behavior of the bridge before and after the repairs. There is a dearth of sensor verified observations of excessive pavement pressure acting on conventional bridges. The sensor data provided in-depth information on the response of the distressed bridge before and after repairs to thermal loading. Prior to the repairs the approach pavement was pushing on the bridge deck and causing the abutment backwalls to tilt toward the bridge. Following the repairs, the approach pavement is no longer pushing on the bridge deck. However, the abutment backwall is now moving in response to thermal changes in the bridge deck, likely due to excessive friction between the deck and the abutment backwall. U-shaped shaped cracking and spalling, previously observed in integral abutment bridges, was observed at this conventional abutment bridge, and the mechanisms causing these cracks and spalling are discussed. Through this study it was found that placement of pavement pressure relief joints relative to the bridge is crucial for reducing the magnitude of stress acting on the bridge. It was also found that the pavement stress acting on a bridge deck can be estimated with vibrating wire strain gauges given a baseline strain response for the approach pavement. [ABSTRACT FROM AUTHOR]

Prediction and monitoring of urban sprawl is a significant urban issue for planners, decision makers, and local authorities in terms of spatial data, strategies, and prediction models. Egyptian cities have expanded rapidly in the last 40 years. This uncontrolled urban growth requires a review of Egyptian urban policies and regulations. The Greater Cairo Region (GCR) is Egypt's economic capital and a significant industrial and commercial city. This study uses spatio-temporal data to suggest an approach based on integrating cellular automata (CA) and multicriteria evaluation (MCE) like analytical hierarchy process (AHP) and running it within the geographical information system (GIS) for monitoring, analyzing, and allocating informal growth in the context of unplanned regions like the GCR. At first, the weights of influencing growth factors were determined and calculated using AHP. Next, the probability map was created according to AHP weights. The historical probability map was then generated based on the historical development. Then a standalone CA macro was developed based on AHP weights to calculate the proximity index for existing urban and transportation features using Moore's extended neighborhood matrix. Finally, the general suitability map was created to identify the most sensitive areas for growth over the next two decades. The prediction process was performed based on the 2012 urban boundary. Then, the prediction accuracy was verified using the Kappa coefficient based on actual urban extents in 2017. The results showed that 676 km2 (35%) of the study area was not sensitive, 386.5 km2 (20%) was slightly sensitive, 522 km2 (27%) was almost sensitive, and 348 km2 (18%) was extremely sensitive to urban sprawl. Finally, we predicted the urban growth for the period from 2022 to 2052 for every 5 years. The outcomes showed a linear scattered sprawl pattern along transportation features and an annular pattern around existing urban spaces. Therefore, fertile farming land and natural resources in the GCR are set to become almost extinct over the next two decades, threatening food production and security. These results indicate the necessity to modify the region's urban policies to protect the agricultural areas and control the unplanned urban sprawl. [ABSTRACT FROM AUTHOR]

Residential shelter performance, in the aftermath of the devastating May 20, 2013, EF5 tornado that struck Moore, Oklahoma, was investigated by a reconnaissance team comprised of researchers from several universities. The team observed and documented 75 residential shelters along the tornado damage path and noted that the concept of shared shelter use was responsible for saving many lives. All belowground shelters performed well with no evidence of structural compromise or shelter breach from debris missiles; however, debris was occasionally observed blocking the opening of the garage slab residential shelters and flooding was also noted in a few cases. Although less common, the majority of above ground residential shelters observed were found in areas that experienced EF3-EF4 estimated wind speeds. In all cases but one, the above ground safe rooms performed well. A debris missile breach of an insulated concrete form (ICF) safe room was documented. While poor construction quality, specifically poor concrete consolidation in areas where plastic cross-ties held the form together, was found to be the major contributing factor in this failure, other factors such as safe room placement within the house and the type of missile (thin-walled steel square tubing) also contributed to this failure. [ABSTRACT FROM AUTHOR]