【作者】 罗士梅；

【导师】 刘奉银；

【作者基本信息】 西安理工大学 ， 岩土工程， 2008， 硕士

【摘要】 我国应用静力触探技术已经有50多年的历史,与传统的钻探相比,静力触探具有资料连续、直观、可靠和重复性好的特点。作为目前原位测试方法中常用的一种测试手段,静力触探已经广泛应用于岩土工程,在工程勘察中占有很重要的位置。但是由于目前静力触探设备受到触探能力的限制,使其难以在坚硬黄土及软岩等硬质地层中获得准确的测试成果。本文对西安理工大学研制的新型旋转触探仪进行了合理性和准确性的试验验证,结果表明该试验仪器完成了可以单独控制触探力、触探速度或旋转速度,可以控制和施加试样所受的围压和轴向压力,用来模拟试样所处的不同深度处受到的地层压力,达到了仪器开发研制的目的。本文应用新型旋转触探仪对陕西西安黄土进行了室内试验研究,通过与国内常用的传统静力触探试验方法进行对比,结果显示旋转能够有效提高触探设备的触探能力。根据已有的触探阻力计算理论,分析了旋转触探阻力的影响因素,这些因素主要包括探头直径、锥尖角度、触探速度,本文的试验结果还揭示旋转速度对触探阻力也有一定影响。通过对比各种不同的参数对旋转触探锥尖阻力的影响结果,进行了详细的分析研究,为更有效地提高触探能力提供了有力的证据。旋转触探试验中的锥尖阻力还与土样自身的性质有着密切的关系,本文在验证新仪器准确、合理性的基础上,定量地研究了旋转触探试验中的关键参数:探头锥尖阻力和旋转扭矩与黄土的干密度、含水量和强度指标之间的关系,得出了各自的经验拟合关系。为进一步扩展旋转触探在实际硬质地层中的应用,进而为室内旋转触探试验最终走向现场迈出了坚实的一步。更多还原

【Abstract】 Cone penetration test (CPT) has been gradually used more than 50 years in China in a wide area of engineering, and now is accepted by geotechnical engineers as an in-situ testing measure. Compared with traditional drilling testing, CPT has many advantages, such as its continuum of data obtain, intuitive, reliability and repeatability. CPT, as a common by used in-situ testing measure, has a very important status in engineering reconnaissance, and has been applied widely into the actual projects. However, the limitation of penetration capability of cone penetration apparatus sets an obstacle on accurate determination in hardpans, such as hard loess and soft rock layers.In this paper, the accuracy and rationality of the newly developed rotary penetration apparatus have been verified, and the conclusion is that this apparatus can control the penetration force, the velocity of penetration or rotary velocity respectively. In addition, it is concluded that the apparatus can simulate the sample compressed by layers in different depth by controlling and imposing the lateral pressure and vertical pressure on the sample.The research focuses mainly on the rotary penetration in Xi’an Loess in laboratory. Through the comparison of the domestically common-used testing approach and the rotary penetration approach, it is proved that the rotary penetration apparatus can improve the penetration capability. The analysis shows that, the main penetration ability is influenced by the effect factors as follows: the diameter of cone probe, the velocity of penetration, and velocity of rotary. With the comparison of Probe resistance results calculated with different parameters, the analysiss, has given strong evidences to support that the apparatus can improve the capacity of penetration.The probe resistance in the rotary penetration has a closed relationship with the sample property, and another important outcome in this paper is about the quantitative analysis on the relationship between loess shear strength strength and key testing parameters, such as probe resistance and rotating torque, which is on the foundation of the new apparatus’s veracity and rationality. This work significantly extends the application of rotary penetration from laboratory test to actual applications.更多还原