Landslide hazard assessment of the 2008 Wenchuan earthquake: a case study in Beichuan area

2011 ◽  
Vol 48 (1) ◽  
pp. 128-145 ◽  
Author(s):  
Chuan Tang ◽  
Jing Zhu ◽  
Xin Qi
Keyword(s):  
Wenchuan Earthquake ◽  
Large Scale ◽  
Landslide Hazard ◽  
Landslide Risk ◽  
Reconstruction Process ◽  
2008 Wenchuan Earthquake ◽  
Landslide Occurrence ◽  
The Wenchuan Earthquake ◽  
Very High ◽  
Earthquake Area

The Wenchuan earthquake (magnitude Ms = 8.0) of 12 May 2008 triggered widespread and large-scale landslides over an area of about 50 000 km2. A study was undertaken to determine the primary factors associated with seismic landslide occurrence. An index-based approach used to assess earthquake-triggered landslide hazard in the central part of the Wenchuan earthquake area affected is described. Slope gradient, relief amplitude, lithology, bedding–slope relations, fault proximity, stream proximity, and antecedent rainfall are recognized as factors that may have had an important influence on landslide occurrence. The assessment of the influence of each of these factors is presented through use of a series of maps showing areas of low, moderate, high, and very high landslide hazard. Areas identified as having “very high and high landslide hazard” were located along the earthquake-source fault and along both banks of the Jian River. The role of rainfall is very significant for future landslide occurrence in the earthquake area. The results of this study will assist decision makers in the selection of safe sites during the reconstruction process. The maps can also be used for landslide risk management in the study area.

scholarly journals Valuable Clues for DCNN-Based Landslide Detection from a Comparative Assessment in the Wenchuan Earthquake Area

Sensors ◽  
2021 ◽  
Vol 21 (15) ◽  
pp. 5191
Author(s):  
Chang Li ◽  
Bangjin Yi ◽  
Peng Gao ◽  
Hui Li ◽  
Jixing Sun ◽  
...  
Keyword(s):  
Wenchuan Earthquake ◽  
Remote Sensing Images ◽  
Machine Learning Methods ◽  
The Wenchuan Earthquake ◽  
Causative Factors ◽  
Multiple Structures ◽  
Sample Set ◽  
Larger Sample ◽  
Structure Layer ◽  
Earthquake Area

Landslide inventories could provide fundamental data for analyzing the causative factors and deformation mechanisms of landslide events. Considering that it is still hard to detect landslides automatically from remote sensing images, endeavors have been carried out to explore the potential of DCNNs on landslide detection, and obtained better performance than shallow machine learning methods. However, there is often confusion as to which structure, layer number, and sample size are better for a project. To fill this gap, this study conducted a comparative test on typical models for landside detection in the Wenchuan earthquake area, where about 200,000 secondary landslides were available. Multiple structures and layer numbers, including VGG16, VGG19, ResNet50, ResNet101, DenseNet120, DenseNet201, UNet−, UNet+, and ResUNet were investigated with different sample numbers (100, 1000, and 10,000). Results indicate that VGG models have the highest precision (about 0.9) but the lowest recall (below 0.76); ResNet models display the lowest precision (below 0.86) and a high recall (about 0.85); DenseNet models obtain moderate precision (below 0.88) and recall (about 0.8); while UNet+ also achieves moderate precision (0.8) and recall (0.84). Generally, a larger sample set can lead to better performance for VGG, ResNet, and DenseNet, and deeper layers could improve the detection results for ResNet and DenseNet. This study provides valuable clues for designing models’ type, layers, and sample set, based on tests with a large number of samples.

The Practical Research of Engineering Materials for the Temporary House after Earthquake

2014 ◽  
Vol 978 ◽  
pp. 27-30
Author(s):  
Si Ru Qian
Keyword(s):  
Wenchuan Earthquake ◽  
Large Scale ◽  
Earthquake Disaster ◽  
The Wenchuan Earthquake ◽  
Disaster Area ◽  
Practical Research ◽  
Engineering Materials ◽  
First Time ◽  
Large Scale Project

After the WenChuan earthquake in may 12,2008,Many province government built the temporary houses for earthquake disaster area.For the first time, they initiate such large scale project, there are many problems emerged during the process of construction such problem like economy ,environment, engineering materials and technology. In this article, we collect problems and analysis them ,seek for the possible measures of construct the temporary house and the effective way to rebuilt the disaster area.

Initiation processes for run-off generated debris flows in the Wenchuan earthquake area of China

Geomorphology ◽  
2016 ◽  
Vol 253 ◽  
pp. 468-477 ◽  
Author(s):  
W. Hu ◽  
X.J. Dong ◽  
Q. Xu ◽  
G.H. Wang ◽  
T.W.J. van Asch ◽  
...  
Keyword(s):  
Wenchuan Earthquake ◽  
Debris Flows ◽  
The Wenchuan Earthquake ◽  
Run Off ◽  
Earthquake Area

scholarly journals Monitoring of the reconstruction process in a high mountainous area affected by a major earthquake and subsequent hazards

2020 ◽  
Vol 20 (4) ◽  
pp. 1163-1186 ◽  
Author(s):  
Chenxiao Tang ◽  
Xinlei Liu ◽  
Yinghua Cai ◽  
Cees Van Westen ◽  
Yu Yang ◽  
...  
Keyword(s):  
Wenchuan Earthquake ◽  
Economic Value ◽  
Image Interpretation ◽  
Economic Loss ◽  
Field Investigation ◽  
Mitigation Measures ◽  
Mountainous Area ◽  
Reconstruction Process ◽  
2008 Wenchuan Earthquake ◽  
Recovery Planning

Abstract. Recovering from major earthquakes is a challenge, especially in mountainous environments where postearthquake hazards may cause substantial impacts for prolonged periods of time. Although such impacts were reported in the 1923 Great Kantō earthquake and the 1999 Chi-Chi earthquake, careless reconstruction in hazard-prone areas and consequently huge losses were witnessed following the 2008 Wenchuan earthquake in the Sichuan province of China, as several reconstructed settlements were severely damaged by mass movements and floods. In order to summarize experiences and identify problems in the reconstruction planning, a monitoring of one of the settlements, the town of Longchi, was carried out by image interpretation and field investigation. Seven inventories containing buildings, farmlands, roads and mitigation measures were made to study the dynamics of elements at risk and exposure over a period of 11 years. It was found that the total economic value of the newly reconstructed buildings was several times more than in the preearthquake situation in 2007, because of enormous governmental investment. Postseismic hazards were not sufficiently taken into consideration in the recovery planning before the catastrophic debris flow disaster in 2010. As a result, the direct economic loss from postseismic disasters was slightly more than the loss caused by the Wenchuan earthquake itself. The society showed an impact-adapt pattern, experiencing losses from disasters and then gaining resistance by abandoning buildings in hazard-prone areas and installing mitigation measures. The locations potentially exposed to postearthquake hazards were summarized, and a possible timetable for reconstruction was proposed. Problems might be encountered in hazard assessment, and possible solutions were discussed.

Recent Advances in Gravelly Soils Liquefaction Evaluation

2011 ◽  
Vol 90-93 ◽  
pp. 1443-1446
Author(s):  
Long Qing Hou ◽  
Ai Fei Li ◽  
Hong Mei Xu ◽  
Chun Feng He ◽  
Peng Hu
Keyword(s):  
Wenchuan Earthquake ◽  
Evaluation Method ◽  
Large Diameter ◽  
Penetration Test ◽  
2008 Wenchuan Earthquake ◽  
Moderate Density ◽  
Grain Sizes ◽  
Triaxial Apparatus ◽  
The Wenchuan Earthquake ◽  
Gravelly Soils

Many gravelly soils liquefied cases history especially in the 2008 Wenchuan earthquake warn that loose to moderate density of gravels have much potential to liquefy under a given earthquake shaking. The large diameter triaxial apparatus is a relative feasible means to explore the liquefaction mechanism of gravelly soils to some extent. Becker penetration test (BPT) could be droved hrough gravelly soils layer, but BPT was not directly correlated with field behavior. Because of a wider range of grain sizes than those reported from previous earthquakes, gravels characteristics liquefied in the Wenchuan earthquake are representative and universal. The gravels liquefaction evaluation method developed from the Wenchuan earthquake should be feasible for worldwide use. The recent and ongoing developments in gravels liquefaction was highlighted

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