柳州红黏土是一种特殊土,具有较多的团粒结构,依据土工试验规范及对试验方法所作相应改进,开展了不同浓度的六偏磷酸钠颗粒分析试验(密度计法)。试验结果表明:柳州红黏土适宜采用0.06%~0.07%的六偏磷酸钠进行分散(相对于1 000 m L),在...柳州红黏土是一种特殊土,具有较多的团粒结构,依据土工试验规范及对试验方法所作相应改进,开展了不同浓度的六偏磷酸钠颗粒分析试验(密度计法)。试验结果表明:柳州红黏土适宜采用0.06%~0.07%的六偏磷酸钠进行分散(相对于1 000 m L),在此浓度区间六偏磷酸钠的分散效果最佳,有较好的稳定性。此结论明确了土试样差异性对颗分试验结果的影响,使得出的结果更精确。根据试验结果,对六偏磷酸钠的作用机理进行了分析和讨论。展开更多
An approach of limit state equation for surrounding rock was put forward based on deformation criterion. A method of symmetrical sampling of basic random variables adopted by classical response surface method was mend...An approach of limit state equation for surrounding rock was put forward based on deformation criterion. A method of symmetrical sampling of basic random variables adopted by classical response surface method was mended, and peak value and deflection degree of basic random variables distribution curve were took into account in the mended sampling method. A calculation way of probability moment, based on mended Rosenbluth method, suitable for non-explicit performance function was put forward. The first, second, third and fourth order moments of functional function value were calculated by mended Rosenbluth method through the first, second, third and fourth order moments of basic random variable. A probability density the function（PDF） of functional function was deduced through its first, second, third and fourth moments, the PDF in the new method took the place of the method of quadratic polynomial to approximate real functional function and reliability probability was calculated through integral by the PDF for random variable of functional function value in the new method. The result shows that the improved response surface method can adapt to various statistic distribution types of basic random variables, its calculation process is legible and need not itemtive circulation. In addition, a stability probability of surrounding rock for a tunnel was calculated by the improved method, whose workload is only 30% of classical method and its accuracy is comparative.展开更多
文摘柳州红黏土是一种特殊土,具有较多的团粒结构,依据土工试验规范及对试验方法所作相应改进,开展了不同浓度的六偏磷酸钠颗粒分析试验(密度计法)。试验结果表明:柳州红黏土适宜采用0.06%~0.07%的六偏磷酸钠进行分散(相对于1 000 m L),在此浓度区间六偏磷酸钠的分散效果最佳,有较好的稳定性。此结论明确了土试样差异性对颗分试验结果的影响,使得出的结果更精确。根据试验结果,对六偏磷酸钠的作用机理进行了分析和讨论。
基金Project(50378036) supported by the National Natural Science Foundation of China Project (200503) supported by the Foundation ofCommunications Department of Hunan Province, China
文摘An approach of limit state equation for surrounding rock was put forward based on deformation criterion. A method of symmetrical sampling of basic random variables adopted by classical response surface method was mended, and peak value and deflection degree of basic random variables distribution curve were took into account in the mended sampling method. A calculation way of probability moment, based on mended Rosenbluth method, suitable for non-explicit performance function was put forward. The first, second, third and fourth order moments of functional function value were calculated by mended Rosenbluth method through the first, second, third and fourth order moments of basic random variable. A probability density the function（PDF） of functional function was deduced through its first, second, third and fourth moments, the PDF in the new method took the place of the method of quadratic polynomial to approximate real functional function and reliability probability was calculated through integral by the PDF for random variable of functional function value in the new method. The result shows that the improved response surface method can adapt to various statistic distribution types of basic random variables, its calculation process is legible and need not itemtive circulation. In addition, a stability probability of surrounding rock for a tunnel was calculated by the improved method, whose workload is only 30% of classical method and its accuracy is comparative.
