【作者】 李兵；

【导师】 阎宗岭；

【作者基本信息】 重庆交通大学 ， 道路与铁道工程， 2011， 硕士

【摘要】 由于传统的路基施工质量检测与评价方法—压实度检测法在巨粒土路基检测中具有很大的局限性,难以适用。论文依托重庆市科技攻关项目“基于不均匀沉降控制的山区巨粒土路基质量评价指标与检测方法研究”,在借鉴国内外相关研究成果的基础上,基于目前国际上的先进方法和技术水平,采用理论分析、室内试验、实体工程应用等方法和手段,对瑞雷波在巨粒土路基中传播的横波波速和动态回弹模量之间的关系进行了较系统、深入地研究。运用动态回弹模量来检测、评价巨粒土路基的施工质量。首先,介绍了瑞雷波检测的理论基础,分析了瑞雷波频散曲线的正反演方法及影响频散曲线的因素。论文利用改进的Knopoff方法,较好地解决了高频有效数字的损失。在瑞雷波反演中采用改进的小生境遗传算法,实现了变参数和定深度遗传反演,缩短了分析时间,提高了分析准确率。其次,基于瑞雷波的频散特性及瑞雷横波波速与巨粒土路基动态回弹模量间的密切相关性,结合附加质量法获取巨粒土路基的密度和纵波波速。并将其作为初始值反演瑞雷横波波速,按照巨粒土路基层厚度加权平均,最终得到巨粒土路基动态回弹模量的表达式。采用由重庆交通科研设计院自主编制开发的多道面波分析系统MASW处理波动检测数据,反演横波波速,由此计算巨粒土路基的动态模量并与FWD(落锤式弯沉仪)结果相互验证。最后,将瑞雷波法应用到实体工程中,结果显示,附加质量法计算巨粒土路基的干密度和水袋法结果比较一致,具备较高的精度,可以由附加质量法获取巨粒土路基的密度作为瑞雷波反演的初始值;瑞雷波法测试的巨粒土路基动态回弹模量和FWD法测试的结果虽然具有一定的误差,但满足一定的误差范围,在工程中是可以接受的。因此,可以用瑞雷波方法检测巨粒土路基的动态回弹模量来评价其施工质量。更多还原

【Abstract】 Because compaction degree used to evaluate the quality of giant grain of soil subgrade has many deficiencies,the paper relying on chongqing torch-plan projects,“research on mountain giant grain of soil subgrade quality evaluation and test methods based on the uneven settlement control”,refering to related research achievements and advanced methods and techniques at home and abroad,the theoretical analysis,laboratory test,engineering application,etc.used to study the relationship between Rayleigh shear wave speed and dynamic resilience modulus in giant grain of soil subgrade.The dynamic resilience modulus is used to detecte and evaluate the subgrade with giant grain of soil.Firstly,this paper introduces the theoretical basis of Rayleigh wave detection,then analyzes in-version methods and influence factors of Rayleigh wave dispersion curves.It solves the problem of the high-frequency effective digital loss to use improved Schwab-Knopoff. The variable parameter and constantly depth niche genetic algorithm used to inverse Rayleigh shear wave speed can shorten the analysis time and improve the analysis accuracy.Secondly,based on the close correlation between Rayleigh shear wave speed and dynamic resilience modulus and disperse characteristics of Rayleigh wave in subgrade with giant grain of soil,additional mass method used to get density and vertical wave in subgrade with giant grain of soil.Then the paper puts the results as the initial value to inverse Rayleigh shear wave speed,on a weighted average of the subgrade layer thickness to gain the calculated mode of dynamic resilience modulus in giant grain of soil subgrade.Using MASW,which developed by Chongqing Traffic Research Institute independently,to deal with data from wave detection and inverse Rayleigh shear wave speed.Thus calculates dynamic modulus and verifies it by the results from FWD (Falling Weight Deflectometer).Finally,the results from Rayleigh wave method used in practical engineering projects show that the additional mass method used to calculate giant grain subgrade dry density can get a high precision compared with the water replacement method,so it can be used as the initial value to inverse shear wave speed;although the dynamic resilience modulus got by Rayleigh wave method has certain error compared with test results from FWD,it can meet certain error range,so it can be acceptable in engineering. Therefore,the dynamic resilience modulus detected by Rayleigh wave method used to evaluate construction quality of the subgrade with giant grain is feasible.更多还原