Search

The mountainous areas of the Loess Plateau in China are crisscrossed with ravines, fragile ecological environment, and frequent landslide hazards. Landslides often cause building collapses and casualties, seriously affecting the sustainability of economic and social development in the region. In order to study the damage of loess landslides to village and town buildings, the paper takes the Xingwang landslide in Fugu County, Shaanxi Province, China as an example, and uses discrete element method and finite element method to study the dynamic process of landslide and its damage to houses. Firstly, the geological characteristics of the landslide were identified by means of investigation, surveying, engineering exploration and geotechnical testing. Secondly, a threedimensional numerical model of the landslide area was established by using the particle flow code system (PFC[sup 3D]). Finally, the entire movement process of the landslide was simulated, and the impact damage to houses induced from landslide was analyzed and predicted. The results show that the whole movement of the landslide lasted a total of 180 s, with a maximum average velocity of 2.01 m/s and a maximum average displacement of 73.7 m. The first and second rows of houses located at the foot of the landslide will suffer serious damage, with most bricks displacement ranging from 0.1 to 2.5 m and a maximum displacement of 10.3 m, posing a serious safety risk to the houses. Only a portion of the third row houses will be damaged, and the fourth row houses will not be threatened by landslide. By comparing with the prediction results of other methods and the current situation of buildings deformation, the results of this paper have a certain credibility. This study provides a numerical method for quantitative assessment of the risk and building damage for loess landslide, which can be used as a reference. It also provides technical support for formulating hazard prevention and reduction plans for the Xingwang landslide. [ABSTRACT FROM AUTHOR]

The Huangshui River Basin, an important upstream tributary of the upper reaches of the Yellow River, serves as the political, economic, and cultural center of Qinghai Province, and is also a region with a high incidence of geological disasters. Within this basin, various types of disasters occur frequently, resulting in significant economic losses and casualties. These disasters also exhibit distinct regional characteristics. Based on the analysis of landform, geological rock group, geological structure, hydrometeorology and human engineering activities in the Huangshui River Basin, the comprehensive classification standard of geological disaster susceptibility was established, and the susceptibility of landslide disaster in the Huangshui River Basin was categorized into five levels: extremely high, high, medium, low and very low. Using a matlab-based platform for catastrophe theory, the inherent relationships among various assessment factors are fully considered, and the single-point disaster risk evaluation is extended to regional disaster susceptibility evaluation. Validation of the assessment results through ROC analysis demonstrates the high accuracy of this method, providing theoretical support for geological disaster prevention and control. [ABSTRACT FROM AUTHOR]

Objective: To evaluate the surgical techniques of open reduction and internal fixation performed for ankle fracture retrospectively and the corresponding clinical outcomes., Methods: From March 2001 to January 2006, 242 patients with ankle fracture were treated. A total of 85 patients with complete clinical data were analyzed. According to the Lauge-Hansen classification system, the fractures were classified into pronation-external rotation (grade II) in 12 cases and grade IV in 9 cases, supination-external rotation (grade II) in 34 cases and grade IV in 16 cases, supination-adduction (grade II) in 8 cases, and pronation-abduction in 6 cases. The reduction and internal fixation started with lateral malleolus, then medial malleolus and posterior malleolus, and distal tibiofibular syndesmosis in sequence. Among 10 cases, 5 of the distal tibiofibular syndesmosis were fixed with one screw through 3 layers of bone cortexes. All cases were auxiliarily fixed with plaster pad for 4 to 6 weeks after operation., Results: The follow-up period varied from 6 to 36 months, with an average of 10 months. There were no local complications such as malunion or nonunion of the fractures and deformity of the ankle. The inserted screw to distal tibiofibular syndesmosis was not broken. The patients were evaluated with Baird-Jackson scoring system. The numbers of the patients who had excellent, good, fair and poor results were 53, 23, 6, 3, respectively. The excellent and good rate was 89.4%., Conclusion: Operative treatment may provide satisfactory clinnical outcomes for ankle fracture. Proper internal fixation and correct fracture pattern estimation are of importance to achieve and gain better long-term results.