【作者】 高颂东；

【导师】 郑刚；

【作者基本信息】 天津大学 ， 土木工程， 2006， 硕士

【摘要】 静力触探作为一种日臻完善的原位测试技术已经越来越为广大岩土工程技术人员所接受。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。本文首先对静力触探技术的发展、现状及其理论基础进行了分析与介绍。结合在天津地区完成的勘察资料,对静力触探的应用从以下几个方面进行了深入探讨和研究:1.分析天津软土地区不同成因时代的地基土静力触探曲线的特征;2.验证贯入阻力的换算;3.验证利用静力触探参数确定地基土的名称;4.研究静力触探参数与地基土物理力学指标的相关分析,得出经验公式,包括静力触探参数与地基土的重度、压缩模量、标准贯入击数和剪切波速的相关经验公式;5.通过静力触探参数与桩静载荷试验结果的对比,研究利用静力触探参数估算桩基承载力的经验公式。研究方法是:搜集整理天津市区和塘沽地区岩土工程项目勘察、设计、施工、测试等大量资料,进一步搜集有关文献、资料后,结合生产实际进行综合分析与研究;利用计算机程序对数据进行一元和多元回归,回归形式力求全面,具有普遍性和实用性;得出经验公式;勘察回访。通过回访调研,将勘察报告中所提的岩土参数与实际进行对比分析,积累资料,对经验公式进行完善。经过分析研究,归纳总结了天津地区的地基土静力触探曲线的特征,为利用静力触探资料进行土层划分和土性分析等提供了区域经验;得出了关于比贯入阻力与静探端阻的换算关系;得出了qc与土的天然重度γ、压缩模量E_s、标贯击数N_63.5和剪切波速V_s的相关公式;得出了利用静力触探估算钻孔灌注桩和沉管灌注桩极限承载力的经验公式。经实际工程对比验证,这些公式均具有一定的适用性。更多还原

【Abstract】 As an important in-situ soil testing method, CPT (cone penetration test) has been accepted by more and more geotechnical engineers. China has a history of more than 50 years in applying CPT. Compared with the traditonal drilling method, CPT is charaterized by continuous and visible data, reliability and good repetitiveness.This paper first analyzes and introduces the development, status quo and theoretic basis of CPT. Based on the survey data completed in Tianjin, this paper discusses and studies in depth the application of CPT in the following aspects:1. Analyze the characteristics of CPT curves of the subsoils with different origin periods in Tianjin soft soil area.2. Verify the conversion formulas of the specific penetration resistance and cone tip resistance.3. Verify the naming of subsoils by CPT parameters.4. Correlation analysis of CPT parameters and physical and mechanical indexes of subsoils, empirical formulas eduction between CPT parameters and subsoil specific weight, modulus of compressibility, blow numbers of standard penetration test and shear wave velocity.5. Discuss how to use CPT parameters to estimate the ultimate bearing capacity of a single pile and empirical formulas eduction through the comparison of CPT parameters and the results of pile static loading tests.The method employed in this paper includes (1) collection of the data and information of survey, design, construction and testing of the geotechnical engineering projects in Tianjin urban area and TEDA. (2) comprehensive analysis and study; one-variate and multivariate correlation analysis of the collectd data by computer programme; empirical formulas eduction; verification of the empirical formulas, make comparison and analysis of the estimated values and the actual values, perfect the empirical formulas.Based on the above mentioned analysis and study, the paper summarizes the characteristics of CPT curves of the subsoils with different origin periods in Tianjin soft soil area, which can provide regional experiences for CPT soil classification and layer division and suggests a conversion formula for the specific penetration resistance and cone tip resistance; establishes the correlative formulas between the cone tip resistance qc and subsoil specific weightγ, modulus of compressibility Es, blow numbers N63.5 of standard penetration test and shear wave velocity Vs; establishes the empirical formulas for estimation by CPT parameters of the ultimate bearing capacity of cast-in-situ bored pile and vibro-sinking pile. These formulas have been verified in actual engineering projects and have proved rational and applicable.更多还原