Studies of sediment hazards and associated countermeasures in Venezuela

本联合研究旨在从泥沙动力学的角度分析1999年泥沙灾害，为泥沙灾害防治提供可靠的工具，并对四个子课题进行了研究。1. 委内瑞拉北部加勒比海沿岸地区强降水特征。1999年泥沙径流模拟及灾后泥沙径流特征。3. 3 .泥沙灾害的历史方面。泥沙灾害对策。结果总结如下：1。分析了与暴雨有关的时空尺度气象相互作用。在此基础上，提出了一种从众多事件中区分异常降水的方法。通过将1-D和2-D预测泥沙径流的数学方法应用于1999年的灾害，并使用自灾害以来收集的泥沙径流数据进行了测试。这些肯定是绘制危险地图的有力工具。从泥沙灾害历史方面的研究结果表明，除了适当的结构性对策外，通常的教育绩效、灾害图和相关的土地利用对减少泥沙灾害也很重要。提出了确定碎片控制结构位置、类型和尺寸的数学工具。

This joint research was conducted to analyze 1999-sediment disaster from a viewpoint sediment dynamics as well as to propose reliable tools for countermeasures against sediment hazards, and four sub-topics were studied. 1. Characteristics of heavy rainfall in Caribbean Sea coastal region of north Venezuela. 2. Simulation of 1999-sediment runoffs and sediment runoff characteristics after the disaster. 3. Historical aspects of sediment disasters and 4. Countermeasures of sediment hazards. The results are summarized as follows.1. Meteorological interactions between temporal and spatial scales associated with the heavy rainfall are analyzed. Based on the results, a method is proposed to distinguish an abnormal rainfall from numerous events.2. 1-D and 2-D mathematical methods for predicting sediment runoff are refined by applying them to 1999-disasters and tested using sediment runoff data which have been collected since the disaster. These are assured to be powerful tools in delineating hazard maps.3. The results obtained from the study on historical aspects of sediment disaster suggest that usual education performances, hazard maps and associated land uses are of importance to reduce sediment hazards in addition to proper structural countermeasures.4. Mathematical tools are proposed to specify the location, type and size of debris control structure.