Early Age Response of Jointed Plain Concrete Pavements to Environmental Loads

The behavior of jointed plain concrete pavements during the initial time period following paving provides vital information concerning how the pavement structure will perform throughout its intended life. A primary contributor to the development of stresses in pavements following paving comes from environmental conditions, particularly from differential thermal and moisture gradients throughout the pavement depth.The following study analyzes the response of a jointed plain concrete pavement structure during the period of initial concrete strength gain (first 72 hours after paving) and throughout a full cycle of seasonal conditions (first ten months after paving). The response of the pavement structure is characterized through the analysis of on-site climatic conditions, analysis of embedded strain, temperature, and moisture gages, as well as through manual field data collection.The field data collection effort conducted for this study is described in terms of an overview of the site conditions, construction parameters, instrumentation utilized and data acquisition employed. The climatic response of the pavement structure was analyzed, with particular emphasis on curling and warping.This study investigated the strain response of the pavement structure with respect to the parameters influencing strain location and magnitude. Both the early-age (the first 72-hours after paving) and the seasonal strain response with respect to spatial characteristics and level of restraint were analyzed.Based on the results from this study, the built-in construction gradient was found to be 0.7 °F/in. at the edge of the slab and negligible at midpanel. In general, the measured curvature tended to be 7 percent larger for unrestrained slabs when compared to restrained slabs. The tie and dowel bars produced a reduction in strain with changes in temperature of approximately 0.34 to 0.41 microstrain/°F at locations near the joints. The strains measured in the restrained slabs also tended to be more uniform than for the unrestrained slabs. A couple of seasonal observations were also made. The average strain at midslab was -450 microstrain in the fall and -600 microstrain in the winter with diurnal strain fluctuations being the lowest in the winter. This study also evaluated the drying shrinkage that occurred in the slab. Drying shrinkage increased drastically during the first 50 days after construction and continued through the winter but began to decrease during the spring when rain events occur more frequently

Infrared Structure of Dijet Production at the LHC

Higher order corrections to QCD scattering processes are crucial for phenomenological analyses in hadronic collider environments such as the LHC. In this thesis we consider the infrared divergent structures emerging from Next-to-Next-to-Leading Order (NNLO) perturbative QCD predictions within the antenna subtraction framework. In doing so we elucidate the highly predictive nature of such a construction, driven by the underlying infrared behaviour. The antenna subtraction formalism has previously been applied successfully to the pure-gluon channel in dijet production at NNLO; we present the extension to processes involving two and four quarks at leading order in colour. We derive explicit expressions for subtracting single and double unresolved contributions to various channels required for dijet production in hadronic collisions. Numerical results are presented to illustrate the validity of the subtraction terms in mimicking the physical cross section in the various unresolved limits

The Development and Testing of an Instrument for Doing Fast Time-Resolved Infrared Spectroscopy and the Study of Dimanganese Decacarbonyl Using UV/VIS and FTRIR Spectroscopic Techniques

Over the past three years at Union College, an instrument has been developed that can be used to probe the mechanisms of the photochemistry of transition metal carbonyl compounds. When these complexes are activated with photons, one or two carbonyl ligands are removed from the complex, opening these sites for chemical bonding. Thus, the coordinatively unsaturated species become catalytically active, and can catalyze a wide variety of organic reactions. The intermediates in these catalytic cycles tend to be short-liver lifetimes are usually less than one second), and therefore special instrumnetation must be developed in order to directly observe these intermediates spectrally

Second order QCD corrections to gluonic jet production at hadron colliders

We report on the calculation of the next-to-next-to-leading order (NNLO) QCD corrections to the production of two gluonic jets at hadron colliders. In previous work, we discussed gluonic dijet production in the gluon-gluon channel. Here, for the first time, we update our numerical results to include the leading colour contribution to the production of two gluonic jets via quark-antiquark scattering.Comment: 8 pages, 4 figures, Proceedings of "Loops and Legs in Quantum Field Theory", Weimar April 201

Understanding the national performance of flood forecasting models to guide incident management and investment

The preparation of routine flood guidance statements and formulation of incident management strategies requires national operating agencies to have a firm understanding of the performance of flood forecasting models. Studies of flood forecasting model performance are commonly evaluated on a groupedcatchment or local basis and can lack the analytical consistency required for integration into coherent national assessments. Here, the first nationally consistent analysis of flood forecasting model performance across England and Wales is presented. Application of the assessment framework, accounting for regional and model-type differences, yields a national overview of relative forecasting capability for models in current operational use. To achieve extensive site coverage, information from many existing local performance studies are pooled into a single structure for analysis under a national framework. The performance information spanning a variety of local models is also compared against the area-wide national G2G (Grid-to-Grid) distributed model. An integrated national assessment gives an evidence base of model performance useful for guiding strategic planning and investment in flood forecasting models. A concise single-page Performance Summary has been created for each site model that contains performance statistics, forecast hydrographs and catchment properties to aid operational use. A prototype web portal has been developed to make information on forecasting model performance more accessible and understandable for end-users

Real-time forecasts of flood hazard and impact: some UK experiences

Major UK floods over the last decade have motivated significant technological and scientific advances in operational flood forecasting and warning. New joint forecasting centres between the national hydrological and meteorological operating agencies have been formed that issue a daily, national Flood Guidance Statement (FGS) to the emergency response community. The FGS is based on a Flood Risk Matrix approach that is a function of potential impact severity and likelihood. It has driven an increased demand for robust, accurate and timely forecast and alert information on fluvial and surface water flooding along with impact assessments. The Grid-to-Grid (G2G) distributed hydrological model has been employed across Britain at a 1km resolution to support the FGS. Novel methods for linking dynamic gridded estimates of river flow and surface runoff with more detailed offline flood risk maps have been developed to obtain real-time probabilistic forecasts of potential impacts, leading to operational trials. Examples of the national-scale G2G application are provided along with case studies of forecast flood impact from (i) an operational Surface Water Flooding (SWF) trial during the Glasgow 2014 Commonwealth Games, (ii) SWF developments under the Natural Hazards Partnership over England & Wales, and (iii) fluvial applications in Scotland