刘先珊　张同乐　牛万保

摘要：

采用在线监测系统监测进行随钻参数的采样与分析，建立了派生参数与直测参数的理论表达式，提出了多因素组合的地层比功模型，实现了地层地质条件与随钻参数的有机结合。以重庆市某高压变电站施工场地为依托，建立了不同地层如素填土层、粉质粘土层、砂岩层及泥岩层的地层比功演化曲线，对比地勘信息可知，不同地层的比功值存在显著差异。可见，合理的地层比功阈值是辨识地层类型的重要参量。运用统计学原理对勘测孔附近不同地层的比功值阈值进行保值优化，通过地勘获得的地层信息来验证阈值区间的可靠性。进一步采用如上地层比功阈值对该区域的其他桩位所在地层进行分析验证，说明了地层比功阈值优化的统计方法可行，其阈值区间合理，可用于其他赋存环境的地层比功阈值确定及地层识别。

关键词：

旋挖钻机；随钻参数；比功模型；统计分析；阈值优化

中图分类号：TU473.1

文献标志码：A文章编号：16744764（2017）02005807

Abstract：

The drilling parameters in the rotary drilling process were sampled and analyzed using online monitoring system. The theoretical expressions between the derived parameters and direct sampling parameters were constructed， and the model of formation work ratio considering multifactor combinations was also proposed to realize the perfect integration of geological conditions and drilling parameters. With the case study of a construction field of the high voltage substation in Chongqing， the curves of different formations such as backfilled soil， silty clay sandstone and mudstone formations were described and compared with the geological survey， the comparison presented obvious difference of different formations. The above results indicated that rational work ratio thresholds were significant to identify the strata characteristics. And then， the work ratio threshold of different formations was optimized near the surveying piles based on the statistical analysis theory to prove the reliability of the threshold range of different formations according to the geological information. In addition， the threshold value were used to verify the formations far away from the surveying piles， the results deeply calibrated the proposed method and verified the rationality of the threshold values. Therefore， the proposed method to determine the threshold range based on formation work ratio model can be used to another different formations and strata identification.

Keywords：

rotary drilling rig；drilling parameters；work ratio model；statistical analysis；threshold optimization

旋挖鉆机作为嵌岩桩成孔的一种重要施工方式，其钻进过程中的随钻参数与地层物性特征关联性研究不仅可以作为施工操作时的依据，还可为嵌岩持力层的判定提供基础数据。将旋挖钻机工作过程中的随钻参数进行采样分析，并建立基于相关直测参数与派生参数的理论表达式，提出多因素组合控制的地层比功数学模型，以实现随钻参数判定地层物性特征的目的 [13]。……