Based on experimental data obtained from triaxial tests and a hydrostatic test, a cup model was formulated. Two plastic mechanisms, respectively a deviatoric shearing and a pore collapse, are taken into account. This ...Based on experimental data obtained from triaxial tests and a hydrostatic test, a cup model was formulated. Two plastic mechanisms, respectively a deviatoric shearing and a pore collapse, are taken into account. This model also considers the influence of confining pressure. In this paper, the calibration of the model is detailed and numerical simulations of the main mechanical behavior of cement paste over a large range of stress are described, showing good agreement with experimental results. The ease study shows that this cup model has extensive applicability for cement-based materials and other quasi-brittle and high-porosity materials in a complex stress state.展开更多
Understanding watershed runoff processes is critical for planning effective soil and water management practices and efficiently utilize available water resources. The main objective of this study was to investigate th...Understanding watershed runoff processes is critical for planning effective soil and water management practices and efficiently utilize available water resources. The main objective of this study was to investigate the performance of the Soil and Water Assessment Tool (SWAT) to simulate streamflow from the Bina basin in the Madhya Pradesh state of India. The SWAT model was calibrated and validated on a daily and monthly basis using historical streamflow and weather data from the Bina basin. The Sequential Uncertainty Fitting (SUFI-2) technique in the SWAT? Calibration and Uncertainty Procedures (SWAT-CUP) program was used to assess model uncertainties. The SWAT model performed “satisfactory” and “very good” in simulating streamflow at daily and monthly time steps, respectively. Model calibration results showed that coefficients of determination (R2) values were 0.66 and 0.96;while Nash-Sutcliffe (NSE) values were 0.65 and 0.94 for daily and monthly simulations, respectively. The R2 values of daily and monthly simulations during model validation were 0.65 and 0.72, respectively while the respective NSE values were 0.58 and 0.72. This study demonstrated that the SWAT model could be effectively used to simulate streamflow in the Bina river basin.展开更多
为解决SWAT(soil and water assessment tool)模型在复杂情形下的参数不确定性分析问题,引入参数不确定性分析平台UQ-PyL(Uncertainty Quantification Python Laboratory),开发UQ-PyL与SWAT模型的耦合模块,使得UQ-PyL中的各种算法能够...为解决SWAT(soil and water assessment tool)模型在复杂情形下的参数不确定性分析问题,引入参数不确定性分析平台UQ-PyL(Uncertainty Quantification Python Laboratory),开发UQ-PyL与SWAT模型的耦合模块,使得UQ-PyL中的各种算法能够方便快捷地应用于SWAT模型的参数不确定性分析。为验证UQ-PyL用于SWAT模型参数不确定性分析的效果,在我国不同气候条件下的4个流域构建SWAT模型,综合对比评估UQ-PyL与SWAT-CUP对模型参数的不确定性分析结果。结果表明:UQ-PyL多种敏感性分析方法筛选出的敏感参数比SWAT-CUP单一方法筛选的结果更加合理;使用UQ-PyL率定的参数在4个流域应用中都表现良好,优化后模拟结果的纳什效率系数均在0.55以上,收敛次数在550次以内;在4个流域的模拟中,UQ-PyL能提供计算效率更高的算法ASMO,也能提供模拟结果更准确的算法SCE。综上,与SWAT模型相耦合的UQ-PyL能够支持SWAT模型用户在不同系统下对模型参数进行更高效的不确定性分析研究。展开更多
基金supported by the National Natural Science Foundation of China (Grant No.50808066)the Scientific Research Foundation for Returned Overseas Chinese Scholars
文摘Based on experimental data obtained from triaxial tests and a hydrostatic test, a cup model was formulated. Two plastic mechanisms, respectively a deviatoric shearing and a pore collapse, are taken into account. This model also considers the influence of confining pressure. In this paper, the calibration of the model is detailed and numerical simulations of the main mechanical behavior of cement paste over a large range of stress are described, showing good agreement with experimental results. The ease study shows that this cup model has extensive applicability for cement-based materials and other quasi-brittle and high-porosity materials in a complex stress state.
基金This work was supported by the Projects[NO.20154030 and NO.(2017)5655]from the Science and Technology Department of Guizhou Province and the National Natural Science Foundation of China(No.81873020).
文摘Understanding watershed runoff processes is critical for planning effective soil and water management practices and efficiently utilize available water resources. The main objective of this study was to investigate the performance of the Soil and Water Assessment Tool (SWAT) to simulate streamflow from the Bina basin in the Madhya Pradesh state of India. The SWAT model was calibrated and validated on a daily and monthly basis using historical streamflow and weather data from the Bina basin. The Sequential Uncertainty Fitting (SUFI-2) technique in the SWAT? Calibration and Uncertainty Procedures (SWAT-CUP) program was used to assess model uncertainties. The SWAT model performed “satisfactory” and “very good” in simulating streamflow at daily and monthly time steps, respectively. Model calibration results showed that coefficients of determination (R2) values were 0.66 and 0.96;while Nash-Sutcliffe (NSE) values were 0.65 and 0.94 for daily and monthly simulations, respectively. The R2 values of daily and monthly simulations during model validation were 0.65 and 0.72, respectively while the respective NSE values were 0.58 and 0.72. This study demonstrated that the SWAT model could be effectively used to simulate streamflow in the Bina river basin.
文摘为解决SWAT(soil and water assessment tool)模型在复杂情形下的参数不确定性分析问题,引入参数不确定性分析平台UQ-PyL(Uncertainty Quantification Python Laboratory),开发UQ-PyL与SWAT模型的耦合模块,使得UQ-PyL中的各种算法能够方便快捷地应用于SWAT模型的参数不确定性分析。为验证UQ-PyL用于SWAT模型参数不确定性分析的效果,在我国不同气候条件下的4个流域构建SWAT模型,综合对比评估UQ-PyL与SWAT-CUP对模型参数的不确定性分析结果。结果表明:UQ-PyL多种敏感性分析方法筛选出的敏感参数比SWAT-CUP单一方法筛选的结果更加合理;使用UQ-PyL率定的参数在4个流域应用中都表现良好,优化后模拟结果的纳什效率系数均在0.55以上,收敛次数在550次以内;在4个流域的模拟中,UQ-PyL能提供计算效率更高的算法ASMO,也能提供模拟结果更准确的算法SCE。综上,与SWAT模型相耦合的UQ-PyL能够支持SWAT模型用户在不同系统下对模型参数进行更高效的不确定性分析研究。
