Statistical Analysis Of Shear Wave Velocity In Construction Sites

Shear wave velocity is an important indicator which influence the ability that mediators propagate waves. Soil shear wave velocity is an important parameter which influence the dynamic properties of soil, and it is widely used in engineering practices. In China's The seismic design of buildings standards(GB50011-2001), two indicators are used to classify different sites, and the equivalent shear wave velocity is just one of them. In China's current Project site seismic safety evaluation(GB17741-2005), shear wave velocity should be used in seismic input interface determination and equivalent linear fluctuation method. China's seismic design of other industries, such as The seismic design of structures(GB50191 -93) ,The seismic design of electrical facilities(GB5060-96) and The seismic design of nuclear power plants(GB50267-97), also require to use soil shear wave velocity in sites classification, Therefore, the study of scientific and technical questions related to shear wave velocity is an important study work in geotechnical engineering seismic field. It has important practical meaning and theoretical value.In earthquake-resistance study field, the soil shear wave velocity is mainly used to confirm the seismic input interfaces, the soil layers seismic response analysis and classify sites. Soil is a complex geological body. Different formation causes, structure, composition and history made shear wave velocity great difference in different soil layers at different conditions. As the testing means and conditions limitation, it is very hard or not precise to get soil layers shear wave velocities in some cases. Therefore, it's meaningful to analyze it's distribution characteristics and it's statistic regularity with the current data. The following work was carried out about soil layers shear wave velocity data' statistical analysis in the paper.1.The soil layers seismic response analysis need various parameters, including the shear wave velocity. This paper introduces the identify methods and research status of these parameters. The determinations of the ground motion, the seismic input interface, the soil layers shear wave velocity and soil nonlinear relationship are analyzed and the existing problems are pointed out in this paper.2.The paper introduce the principles and using methods of many soil layers shear wave velocity testing equipments. The different applicability, testing and data analysis methods are comparative analyzed. The advantages and disadvantages of them are pointed out in this paper.3.356 drill holes' shear wave velocity and standard penetration test data were collected. These drill holes located in 121 engineering sites in the middle of Songnen Plain, which around Harbin and its adjacent areas. In this paper, the collected data were classified and collated. The main features of various soil layers were summed up and the shear wave velocity's numerical distribution of different soils at different depths were classification counted. 4.This paper uses the method of regression analysis to classification statistic relationship between different soil layers' shear wave velocities and depths. The statistic mathematical representation of Harbin and surrounding areas' shear wave velocities, depths and statistics values of various parameters in the formulation are given out for the first time. The checked results prove that the statistic relationship has practical value and important guiding significance to engineering.5.The paper analyzes the relationship between soil layer below count of SPT and shear wave velocity. the relationship of the shear wave velocity, below count of SPT and the depth are figured. The mathematical representation and statistics values of different parameters in the formulation are given out, which have important significance.It should be pointed out that the results of mathematical statistics have a certain representation, but it is restricted by the quantity and quality of samples. In this paper, only limited data and a partial information are preliminary counted. This is a preliminary exploration and has some reference value to estimate the shear wave velocity of this area. With the improvement of samples' quantity and quality, this result will have more and more practical value. After all, scientific research is just exploration, so the mistake is unavoidable. To hope that one could correct if there are some problems in this paper.