期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
高速铁路CPII控制网复测稳定性分析指标合理性深入研究 被引量:1
1
作者 曹体涛 刘成龙 王不悔 《测绘》 2021年第6期243-246,279,共5页
根据现行高速铁路工程测量规范要求,CPII控制点的稳定性主要是从原测与复测坐标分量较差和相邻点间坐标差之差的相对精度两项指标判断。在实际应用过程中发现,现行规范中CPII控制点原测与复测坐标分量较差的限差阈值15mm和相邻CPII点间... 根据现行高速铁路工程测量规范要求,CPII控制点的稳定性主要是从原测与复测坐标分量较差和相邻点间坐标差之差的相对精度两项指标判断。在实际应用过程中发现,现行规范中CPII控制点原测与复测坐标分量较差的限差阈值15mm和相邻CPII点间坐标差之差相对精度的限差阈值1/80000对小于600m的短边而言均存在缺陷,这会影响评价CPII控制点复测稳定性的准确度。因此,本文分别推导了基于GNSS测量CPII点的两项稳定性分析指标的合理限差,研究结果对指导实际工作和完善高速铁路工程测量规范有一定参考价值。 展开更多
关键词 CPII控制点 坐标 相对精度 限差阈值
下载PDF
One-dimensional consolidation of double-layered soil with non-Darcian flow described by exponent and threshold gradient 被引量:10
2
作者 李传勋 谢康和 +1 位作者 胡安峰 胡白香 《Journal of Central South University》 SCIE EI CAS 2012年第2期562-571,共10页
Based on non-Darcian flow law described by exponent and threshold gradient within a double-layered soil, the classic theory of one-dimensional consolidation of double-layered soil was modified to consider the change o... Based on non-Darcian flow law described by exponent and threshold gradient within a double-layered soil, the classic theory of one-dimensional consolidation of double-layered soil was modified to consider the change of vertical total stress with depth and time together. Because of the complexity of governing equations, the numerical solutions were obtained in detail by finite difference method. Then, the numerical solutions were compared with the analytical solutions in condition that non-Darcian flow law was degenerated to Dary's law, and the comparison results show that numerical solutions are reliable. Finally, consolidation behavior of double-layered soil with different parameters was analyzed, and the results show that the consolidation rate of double-layered soil decreases with increasing the value of exponent and threshold of non-Darcian flow, and the exponent and threshold gradient of the first soil layer greatly influence the consolidation rate of double-layered soil. The larger the ratio of the equivalent water head of external load to the total thickness of double-layered soil, the larger the rate of the consolidation, and the similitude relationship in classical consolidation theory of double-layered soil is not satisfied. The other consolidation behavior of double-layered soil with non-Darcian flow is the same as that with Darcy's law. 展开更多
关键词 one-dimensional consolidation double-layered soil non-Darcian flow depth dependent vertical total stress timedependent loading
下载PDF
上一页 1 下一页 到第
使用帮助 返回顶部