[1] New methods of data collection and processing are developed to provide quantitative, reach-scale measurements of bedform transport mass within the tidally influenced Mississippi River. A multibeam swath profiler was used to collect daily bathymetry over a range of water discharges, and bed elevation changes induced by dune migration are measured. These values are coupled with bulk physical properties of the bed sediment to constrain mass flux, and annual bedform transport is estimated at 2.2 Â 10 6 metric tons (MT). The total annual sand flux from the Mississippi River, calculated by combining measured bedform transport rates and suspended sediment flux, is estimated to be 20 Â 10 6 MT. Survey data also provide information about the spatial distribution of dunes across the channel bottom. Straight reach segments are commonly mantled by dunes for the entire cross section, while bends are typically areas of focused scour devoid of bedforms. Presumably, any sediments associated with migrating dunes are propelled into suspension within bends before redepositing in the subsequent straight reach. Movement via suspension is therefore an important component for the downriver transport of bed materials in the lower Mississippi River.

Significant advances have been made in recent years in research, development, interpretation, and application of cone penetration testing. The addition of pore pressure measurements during cone penetration testing has added a new dimension to the interpretation of geotechnical parameters.The cone penetration test induces complex changes in stresses and strains around the cone tip. No one has yet developed a comprehensive theoretical solution to this problem. Hence, the cone penetration test provides indices which can be correlated to soil behaviour. Therefore, the interpretation of cone penetration data is made with empirical correlations to obtain required geotechnical parameters.This paper discusses the significant recent developments in cone penetration testing and presents a summarized work guide for practicing engineers for interpretation for soil classification, and parameters for drained conditions during the test such as relative density, drained shear strength, and deformation characteristics of sand. Factors that influence the interpretation are discussed and guidelines provided. The companion paper, Part II: Clay, considers undrained conditions during the test and summarizes recent developments to interpret parameters for clay soils, such as undrained shear strength, deformation characteristics of clay, stress history, consolidation characteristics, permeability, and pore pressure. The advantages and use of the piezometer cone are discussed as a separate topic in Part II: Clay. The authors' personal experiences and current recommendations are included. Keywords: static cone penetration testing, in situ, interpretation, shear strength, modulus, density, stress history, pore pressures.

We analyse decisions to reopen in the aftermath of Hurricane Katrina made by business establishments on major business thoroughfares in New Orleans by using a spatial probit methodology. Our approach allows for interdependence between decisions to reopen by one establishment and those of its neighbours. There is a large literature on the role that is played by spatial dependence in firm location decisions, and we find evidence of strong dependence in decisions by firms to reopen in the aftermath of a natural disaster such as Hurricane Katrina. This interdependence has important statistical implications for how we analyse business recovery after disasters, as well as government aid programmes.

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BackgroundEmpirical observations on how businesses respond after a major catastrophe are rare, especially for a catastrophe as great as Hurricane Katrina, which hit New Orleans, Louisiana on August 29, 2005. We analyzed repeated telephone surveys of New Orleans businesses conducted in December 2005, June 2006, and October 2007 to understand factors that influenced decisions to re-open amid post-disaster uncertainty.Methodology/Principal FindingsBusinesses in the group of professional, scientific, and technical services reopened the fastest in the near term, but differences in the rate of reopening for businesses stratified by type became indistinguishable in the longer term (around two years later). A reopening rate of 65% was found for all businesses by October 2007. Discriminant analysis showed significant differences in responses reflecting their attitudes about important factors between businesses that reopened and those that did not. Businesses that remained closed at the time of our third survey (two years after Katrina) ranked levee protection as the top concern immediately after Katrina, but damage to their premises and financing became major concerns in subsequent months reflected in the later surveys. For businesses that had opened (at the time of our third survey), infrastructure protection including levee, utility, and communications were the main concerns mentioned in surveys up to the third survey, when the issue of crime became their top concern.Conclusions/SignificanceThese findings underscore the need to have public policy and emergency plans in place prior to the actual disaster, such as infrastructure protection, so that the policy can be applied in a timely manner before business decisions to return or close are made. Our survey results, which include responses from both open and closed businesses, overcome the “survivorship bias” problem and provide empirical observations that should be useful to improve micro-level spatial economic modeling of factors that influence business return decisions.

A new test, called the seismic cone penetration test (SCPT) is described.A small rugged velocity seismometer has been incorporated into an electronic cone penetrometer.The combination of the seismic downhole method and the CPT logging provide an extremely rapid, reliable and economic means of determining stratigraphic, strength and modulus information in one sounding.Results using the seismic cone penetration test are presented and compared to conventional in-situ techniques.