A Probabilistic Method to assess the Regional Susceptibility of Landslides induced by Earthquake in Kitakyushu City, Japan

Junjie Sun1*, Lanmin Wang2 and Guangqi Chen3

Here a probabilistic method for assessing the regional susceptibility of landslides induced by earthquake events was developed. This probabilistic method, furthermore, was applied into the Kitakyushu city of Japan, which suffered the landslide disasters induced both by rainfall and earthquake seriously. Failure probability of earthquake-induced landslides based on Monte Carlo simulation (minimizing the uncertainty of slope parameters) and a developed method after New mark stability analysis (estimating factors of safety) was calculated. Meanwhile, regional susceptibility maps of earthquake-induced landslides in Kitakyushu city were produced by using the geographical information system (GIS) with different peak ground accelerations (PGAs) and seismic occurrence periods at both conditions of m=0 and m=1 (m, so-called water factor which means a ratio of groundwater level to thickness of sliding layer). Analysis results of failure probability disclose that the influence factors of slope angle, PGA and m on failure probability (stability) of earthquake-induced landslides would have to be considered carefully in the Kitakyushu city. The PGA exerts distinctly different influence on the stability of landslides varying with soil type and m. According to a new geology map of Kitakyushu city, the maximum average value of slope angles is less than 50 degree. A softer slope tends to suffer a greater increment of failure probability impacted by the PGA in the case of a lower angle than a higher one, within the range of slope angles, 0~50 degree. This becomes more visible while the PGA increases. On the susceptibility maps, it is evident that the districts of Kokura Minami, Moji, Kokura Kita, Yahata Higashi and Yahata Nishi in Kitakyushu city would suffer the disaster of landslide severely. In the lower cases of PGA, the Southwest of Kokura Minami, the borders between Moji and Kokura Kita and the borders between Yahata Higashi and Yahata Nishi are the major areas impacted by extremely serious hazard of earthquake-induced landslides. As PGA, seismic occurrence period or/and m increases, critical disaster of landslide has an extensive area, covering Wakamatsu. Nevertheless, Tobata, the only one of fortunate district throughout Kitakyushu city, is in safety all the time.

Full Text

The Relationship between Earthquake Knowledge and Earthquake Attitudes of Disaster Relief Staffs

Öcal Adem

This study examined the levels of earthquake knowledge and attitudes toward earthquakes of disaster relief staff with respect to various variables. The study was conducted on 112 participants attending the in-service Disaster Education course conducted in December 2008 organized by Burdur Province Civil Defence Directorate. To reach the aim of the study, an earthquake knowledge scale and earthquake attitudes scale were administered to the participants. The participants’ knowledge levels and their attitudes towards earthquakes were analyzed using the SPSS package program. Pearson Product- Moment correlation calculation was performed to determine the relationship between earthquake knowledge and earthquake attitudes among disaster relief staff which has shown that as participants’ knowledge on earthquake increased, their attitude scores also increased at a significant level.

Full Text

Environmental Factor Assessment on Fire Behaviour Characteristics for Surface Forest Layers

Boboulos Miltiadis A.

The methodology, measurements and processing from fire behaviour experiments for the ignition and spreading in Pinus halepensis and Pinus pinaster forest litter are presented in this study. The experiments were carried out in laboratory conditions using a specifically designed set up. The basic independent variables in the course of the experiments were the slope angle of the work plane, the airflow velocity and the fuel moisture content. To provide a quantitative assessment for the effects of parameters on the fire spread and the flame angle during the experiments, statistical processing based on the regression analysis has been carried out. The developed model equations described the terrain slope and wind velocity as determining factors for the examined characteristics. The information acquired in these experiments assist in establishing quantitative relationships between important fire behaviour descriptors and its environment for the formulation of a model predicting fire spreading into surface fuel beds.

Full Text

Application of Space Information Technology on Back-Analysis for Geological Parameters of Engineering Environment

Wang Iau-Teh1* and Lee Chin-Yu2

Geological mechanical parameters are key factors in engineering safety management and disaster prevention in the planning and design phase. This paper develops a back-analysis technique using the infinite slopes stability stratum parameter assessment technique under the GIS and RS platform. The landslide events were calculated based on the infinite slope stability theory consisting of factors including the slope, unit weight, cohesion and angle of friction of the stratum for each regional unit. Using methods developed in this study, the generated scatter charts showed the stratum mechanical parameters for civil works compared to the site located in the southeast area of Hualien, Taiwan. According to the case study and parameter analyses results, the parameter value accuracy approaches to 80.3%. The study also demonstrated that the cohesion and angle of friction of stratum materials have important roles in controlling the safety factor. The results indicate that the back-analysis GIS and RS method provides practical engineering information for the design of potential geologic hazards evaluation. The proposed technique provides a rapid estimation for the safety factors which is quite useful for engineering requirements.

Full Text

Response to Swelling and Permeability of Bentonite using Saline Solution for Nuclear Waste Disposal

Shirazi S.M.,1* Kuwano J.,2 Kazama H.,2 Wiwat S.1 and Ismail Z.2

In order to investigate the effect of salinity on the basic swelling behavior of compacted bentonite, series of one dimensional swelling deformation test have been performed. The tests were conducted with the various initial dry densities (1.33 ~ 1.90 g/cm3) of compacted bentonite saturated with different concentration of NaCl solution varying from 0.5 ~ 4.0 mol/l. It was found that the higher initial dry ensity specimens show higher maximum swelling rate and the maximum swelling rate of bentonite decreased with increasing concentration of NaCl. The permeability of bentonite rapidly increases with increasing concentration of NaCl. NaCl within montmorillonite clay mineral decreases the thickness of double-layer swelling. The bentonite may change from highly swelled material to coagulate in saline water.

Full Text

Land Use Change in Fast Developing Regions: A Case Study of Chongqing Municipality in Southwestern China

Liu Li*1,2, Huang Fang3 and Gao Shuohan4

This study takes into account Chongqing Municipality of China as a typical case and explores the main characteristics of the land use change in a fast developing and urbanization region. Study also demonstrates the magnitude of land use change caused by the land use policy and economic development strategy. The purpose is to improve the understanding of their land use change so that sustainable land utilization could be practiced. Based on the Landsat TM data of 1980, 1995 and 2005, the spatial-temporal characteristics of land use changes within the periods 1980-1995 and 1995-2005 in the study area were quantified using remote sensing and GIS. The method of the dynamism index was used to measure the annual change rate of land use. Results show that land use type in 1980 was mainly dominated by73% of cropland and 20% of forestland; the built up area occupied 4% of the study area; the land use type in 1995 had almost the same character, but in 2005, it was mainly dominated by 49% of cropland and 38% of forestland (37%); the built up area increased to 10% of the study area. There was no big change on land use during the period from 1980 to 1995, however during the period from 1995 to 2005, there was big change on land use by substantial growth of built-up areas and increase of forestland area resulting in significant decrease in the area of cropland and unutilized land. The annual change rate of overall land use during the period from 1995 to 2005 is 3.5% which is larger than that of Shanghai (2.1%) during the same period. The case study shows the tremendous land use changes during the period of fast developing and urbanization which were mainly caused by national policy and strategy.

Full Text

Nonlinear Hydrologic Modeling Using the Stochastic and Neural Networks Approach

Sungwon Kim

The goal of this research is to develop and apply the integrational operation method (IOM) for modeling the relationship of the pan evaporation (PE) and the alfalfa reference evapotranspiration (ETr). Since the observed data of the alfalfa ETr using lysimeter have not been measured for a long time, the Penman-Monteith (PM) method is used to estimate the observed alfalfa ETr. The IOM consists of the combination/application of the stochastic and neural networks models respectively. The stochastic model of Periodic Auto Regressive Moving Average (PARMA) is applied to generate the training dataset for the monthly PE and the alfalfa ETr and the neural networks models are applied to calculate the observed test dataset reasonably. Among the six training patterns, 1,000/PARMA(1,1) /GRNNM-GA training pattern is used which can evaluate the suggested climatic variables very well and construct the reliable data for the monthly PE and the alfalfa ETr. Uncertainty analysis is also used to eliminate the climatic variables of input nodes from the 1,000/PARMA(1,1)/GRNNM-GA training pattern. The sensitive and insensitive climatic variables are chosen from the uncertainty analysis of the input nodes.

Full Text