山东临沂地区砂土剪切波速与标准贯入击数关系统计分析

Statistical analysis of relationship between sand soil shear wave velocity and standard penetration test blow count in Linyi region of Shandong province

剪切波速(V S)与标贯击数(N)之间存在相关关系,受地区土壤条件影响很大。对临沂地区场地实测得到的砂土的剪切波速和标贯击数之间的关系进行了统计分析,得到了砾砂、粗砂、中砂和细砂相应的关系曲线。结果发现受沉积环境的影响,砂土层粒径与埋深呈正相关,砂土粒径越大其密实段样本点数量越多。为消除不同密实程度段之间的相互影响,以密实度为划分标准进一步进行分区段统计分析,得到了不同密实程度的四类砂土的相关关系方程,通过实际钻孔数据对比了分段与不分段的统计分析结果,分段模拟能更好地反映两者之间的相关关系。将砂土根据密实度进行划分再给出剪切波速和标贯击数的回归关系可以提高分析结果的准确性,同时可以考虑土体特性的影响,更为科学。此研究为临沂地区提供了一种简便预估剪切波速的方法,对相关地区的工程建设和科学研究也具有参考价值。

There is a correlation between the shear wave velocity(V S)and standard penetration test blow count(N),which is greatly affected by the soil conditions in the region.The relationship between the shear wave velocity and standard penetration test blow count measured in the site in Linyi area was statistically analyzed,and the corresponding relationship curves of gravel,coarse sand,medium sand and fine sand were obtained.The results show that due to the influence of the sedimentary environment,the particle size of the sandy soil layer is positively correlated with the burial depth,and the larger the particle size of the sandy soil,the greater the number of sample points in the dense section.In order to eliminate the interaction between different density sections,the statistical analysis of the partition segments was further carried out with the compactness as the partitioning criterion,and the correlation equations of the four types of sand with different compactness degrees were obtained,and the accuracy of the two statistical methods was compared through the actual drilling data.Segmented simulations better reflect the relationship between the two.The regression relationship between the shear wave velocity and the standard penetration test blow coun can be divided according to the compactness of the sand,which can improve the accuracy of the analysis results,and consider the influence of soil characteristics,which is more scientific.This study provides a simple method for estimating shear wave velocity in Linyi area,and also has reference value for engineering construction and scientific research in related areas.