Damage Curves Derived from Hurricane Ike in the West of Galveston Bay Based on Insurance Claims and Hydrodynamic Simulations

Hurricane Ike,which struck the United States in September 2008,was the ninth most expensive hurricane in terms of damages.It caused nearly USD 30 billion in damage after making landfall on the Bolivar Peninsula,Texas.We used the Delft3dFM/SWAN hydrodynamic and spectral wave model to simulate the storm surge inundation around Galveston Bay during Hurricane Ike.Damage curves were established through the relationship between eight hydrodynamic parameters(water depth,flow velocity,unit discharge,flow momentum flux,significant wave height,wave energy flux,total water depth(flow depth plus wave height),and total(flow plus wave)force)simulated by the model and National Flood Insurance Program(NFIP)insurance damage data.The NFIP insurance database contains a large amount of building damage data,building stories,and elevation,as well as other information from the Ike event.We found that the damage curves are sensitive to the model grid resolution,building elevation,and the number of stories.We also found that the resulting damage functions are steeper than those developed for residential structures in many other locations.

Neutronic investigation and activation calculation for CFETR HCCB blankets

The neutronic calculations and activation behavior of the proposed helium cooled ceramic breeder（HCCB） blanket were predicted for the Chinese Fusion Engineering Testing Reactor（CFETR） design model using the MCNP multi-particle transport code and its associated data library. The tritium self-sufficiency behavior of the HCCB blanket was assessed, addressing several important breeding-related arrangements inside the blankets. Two candidate first wall armor materials were considered to obtain a proper tritium breeding ratio（TBR）. Presentations of other neutronic characteristics, including neutron flux, neutron-induced damages in terms of the accumulated dpa and helium production were also conducted. Activation, decay heat levels and contact dose rates of the components were calculated to estimate the neutron-induced radioactivity and personnel safety. The results indicate that neutron radiation is efficiently attenuated and slowed down by components placed between the plasma and toroidal field coil.The dominant nuclides and corresponding isotopes in the structural steel were discussed. A radioactivity comparison between pure beryllium and beryllium with specific impurities was also performed. After a millennium cooling time, the decay heat of all the concerned components and materials is less than 1？×？10-4 k W, and most associated in-vessel components qualify for recycling by remote handling. The results demonstrate that acceptable hands-on recycling and operation still require a further long waiting period to allow the activated products to decay.

Quantitative characterization of damage-aggravation effect caused by progressive damage

Aiming at the progressive damage phenomenon in geotechnical field,it attempts to study the effect of progressive damage on the macro-bearing capacity.Firstly,based on the theoretical analysis of a two-dimensional plane inside representative volume element,it is proposed that progressive damage will occur if the bearing capacity of microplanes is different.Besides,“damage-aggravation effect”is proposed according to the difference between the macro-bearing capacity of entire plane and the sum of bearing capacity of all microplanes when progressive damage occurs.Secondly,progressive damage ratio K_(t)is proposed to quantify“damage-aggravation effect”.Finally,based on the rod model,the correspondence between K_(t),and some influence factors is studied by theoretical analysis and numerical simulation.The results show that“damage-aggravation effect”does exist,and the macro-bearing capacity of entire plane is less than the sum of bearing capacity of all microplanes when progressive damage occurs.If the bearing capacity of rods in the rod model obeys uniform distribution,as the minimum of bearing capacity increases linearly,the macro-bearing capacity increases linearly,and K_(t)decreases inversely.

Damage Layer Evolution of a Breakwater Under Seawater Attack: Testing and Modeling

This paper presents experimental and theoretical methods to study the damage layer evolution of a breakwater made with concrete hollow squares in marine environment.Wetting time was directly related to the performance degradation of the breakwater by observation.The thickness of damage layer was detected by means of ultrasonic testing.Meanwhile,some samples drilled from concrete hollow squares were analyzed by SEM and XRD in order to illustrate the damage mechanism.Subsequently,a theoretical model containing wetting time ratio was established to simulate the damage layer evolution based on Fick’s second law,which could be suggested to predict the service life of concrete structures in marine environment.