Vol. 8(6) June 2015
Social vulnerability index to natural hazards: A case
study of Shanghai, China
Yongling Zhang, Lu Chen and Xiaoming Chuai
Natural hazards can cause huge economic losses and serious
damage to the society. The analysis of social vulnerability to natural hazard can
greatly aid decision-making and governance and be also essential for regional disaster
mitigation as well as sustainable development of society. Being taken as example,
Shanghai was chosen to establish a social vulnerability index system of natural
hazards from three dimensions including population, economy and disaster mitigation
based on the analysis of influencing factors of social vulnerability on natural
hazards. The social vulnerability indexes were reduced from 45 to 14 by sensitivity
analysis. Furthermore, the comprehensive social vulnerability indexes were determined
according to population, economy and disaster mitigation including 5 social vulnerability
indexes for population, 3 social vulnerability indexes for economy and 6 social
vulnerability indexes for disaster mitigation. Finally, the SVI for vulnerability
indexes was calculated by collective model and its spatial differences for Shanghai
were analyzed using GIS technology. The study provided an example of the research
on the social vulnerability to natural hazard.
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Grey Rainfall-Stage Model for forecasting Flash Flood
Stages during Typhoons
Shien-Tsung Chen
Typhoons often bring severe rainfall that causes flash
floods and related disasters. An efficient flood forecasting model can provide informative
forecasts to mitigate disasters. This study proposes a grey rainfall-stage model
based on the hydrologic concept of the rainfall-stage process and the assumption
of grey system theory to process hydrologic variables by applying the accumulated
generating operation. Flash flood events in Wu River, Taiwan, during typhoons were
collected as the study data. The proposed grey rainfall-stage model was applied
to forecast flood stages multiple hours ahead. Calibration and validation results
show that the grey rainfall-stage model can perform real-time flood stage forecasting.
Moreover, potential improvements of the grey rainfall-stage model include deriving
various model structures and applying different parameter calibration schemes.
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Parametric study on brick masonry using finite element
method
Vasanthi P., Gopalakrishnan R. and Satyanarayanan K.S.
The properties of brick masonry are influenced by factors
that are related to the brick, mortar, joint and inclination of the applied load
to the bed joint. In order to investigate the influence of load at different inclination
to bed joint for different thickness of mortar compressive strength to the uniaxial
compressive strength of brick masonry, this study is carried out by analytical investigation
using computer finite element software to predict the normal stress, normal elastic
strain and total deformation in ANSYS Workbench 12.0. Nine combinations of unit
to mortar strength (H-H, H-M, H-L, M-H, M-M, M-L, L-H, L-M,L-L), five different
angle of inclinations between load and bed joint (0°, 30°,45°,60°,90°), three different
thickness of mortar joint ( 5 mm, 7.5 mm, 10 mm) and two different materials for
capping (cork, lead) are included from the results, the effective modulus of elasticity
in each case is derived and compared. It is found that the highest value is 16.94
times and lowest value is 0.09 times that of conventional value, namely, that for
bed joint angle of 90°. These highest values occur for the case of H-L strength
parameter and 10 mm thickness with 0° angle. And lowest value occurs for the case
of H-H strength parameter and 5 mm thickness with 90° angle.
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Seismic Design of Pile Foundation for Oil Tank by
using PLAXIS3D
Kumar Ashutosh, Choudhury Deepankar, Shukla Jaykumar and Shah D. L.
Analysis and design of pile foundations in soft soil
strata to support any geotechnical structures especially oil tanks are very important
for geotechnical practitioners and more so in earthquake prone areas. In this paper,
a complete design of pile foundation for oil tank in Iraq is mentioned by providing
the details of soil strata at the site of oil tank construction which is in seismically
active region. A finite element analysis by using PLAXIS3D for the design of pile
foundation for oil tank in Iraq is carried out for both static and seismic loading
conditions. In-situ soil at the site varies from loose fill material followed by
soft to stiff clay layers and then by dense sand layer. First, the basic static
design of suitable pile foundation which is based on field observed ground details
have been carried out in PLAXIS3D. A group of 89 piles of 26m length with 400mm
radius each is proposed for the oil tank of height 15m and 23.5m diameter to withstand
a maximum credible earthquake (MCE) of 0.15g. Results for pile foundations in terms
of settlements, differential settlements between piles, bending moments are obtained
by using finite element numerical modeling using PLAXIS3D and proposed as final
design of the foundation system for oil tank at the specific soft soil site in Iraq.
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