极端气候条件下膨胀土路基水毁灾害预测研究

项目名称： 极端气候条件下膨胀土路基水毁灾害预测研究

项目编号： No.50808179

项目类型： 青年科学基金项目

立项/批准年度： 2009

项目学科： 天文学、地球科学

项目作者： 丁加明

作者单位： 中南大学

项目金额： 20万元

中文摘要： 作为一种典型的浅表层轻型工程，膨胀土路基在正常的自然气候条件下会对建设在其上的路基和构筑物产生较大的危害。近年来极端气候频发，修筑在膨胀土地区的路基发生水毁灾害的情况也越来越多。本项目采用理论分析、室内试验、模型试验和现场试验相结合的方法，研究了极端气候下膨胀土路基水毁损害特征和规律，建立了膨胀土路基水毁灾害预测模型，系统地将粗糙集理论、概率理论、贝叶斯理论和规则提取理论等引入膨胀土路基水毁灾害预测，并全面解决了新方法应用中的系列关键技术问题。提出采用贝叶斯理论提取信息不相容和不完备的试验数据规则。针对训练好的神经网络在相同输入出现不同输出的情况，提出了用蒙特卡洛方法对膨胀土胀缩等级、降雨量、干旱持时和路基坡度等水毁因素进行模拟，再对输出结果进行数理统计，从而确定膨胀土路基水毁的发生概率。研究为当膨胀土路基的地理分布与极端气候耦合时的水毁预测提供了一种可扩展的算法和模型，并可望应用于极端气候条件下的其他灾害预测。

中文关键词： 极端气候；膨胀土路基；水毁；灾害预测；规则提取

英文摘要： As a typical shallow and light engineering, expansive soil roadbed is damaged easily by rainfall and aridity. The extreme climate events take place frequently recently. Water-destroyed of Roadbed on expansive area was gravely affected under the extreme climate events. Theory analysis, general test, mode test, local test are combined in this item. The character and rule of expansive soil roadbed water-destroyed were studied. The forecast mode of water-destroyed for expansive soil roadbed was presented. The rough sets, probability theory, Bayesian theory and generating rule were introduced perfect into this mode. A series of key techniques were resolved completely in the new means application. The generating rule method was presented for incompatible and incomplete information of test data based on Bayesian theory. Due to different outputs for same input in a trained Neural Net, the Monte-Carlo method was presented to simulate the probability of swelling and shrinkage grades, rainfall, drought continuance and roadbed gradient. The probability was inputted to the trained Neural Net. The statistical result of the output was the water-destroyed probability of the expansive soils roadbed. The forecast mode of water-destroyed disaster for expansive soil roadbed was presented under extreme climate conditions. The research indicates that this arithmetic is an expandable one which can calculate water-destroyed probability of the expansive soils roadbed when its geography distributing coupling with extreme climate, and this arithmetic can be also used to forecast other disaster under extreme climate conditions.

英文关键词： extreme climate; expansive soil roadbed; water-destroyed; disaster forecast; generating rule