Application And Research Of CPT In Typical Strata In Hefei Area

Cone penetration test?CPT?,as a common in-situ test method,has the advantages of no sampling,continuous test,good reproducibility and high test accuracy,and is widely used in various geotechnical engineering surveys.CPT is widely used,which can be used to divide soil layer,determine foundation bearing capacity,distinguish sandy soil liquefaction and estimate pile bearing capacity.Quaternary soil layer in Hefei area is widely distributed and thick,and CPT has been widely used in this area for many years,and a large amount of data and experience have been accumulated.This paper collects a large number of engineering survey data in Hefei area,conducts statistical analysis on the CPT data of typical strata in Hefei area,and explores the method to determine the physical and mechanical properties of main soil layers,foundation bearing capacity and single pile bearing capacity by using CPT.Through comparison and selection,this paper adopts Grubbs method to screen the static touch detection test data,eliminate the extreme value,and sort out and analyze the filtered data.In this paper,fractal geometry and statistical methods are used to analyze the CPT curves of typical strata in Hefei area,and the basic characteristics of the CPT curves of different strata are obtained.It is found that the curve of the CPT curve of Hefei old clay is smoother,with smaller span and higher mean line than that of Q₄ clay.Paper will the static detection test results and the Hefei typical stratigraphic correlation analysis of physical and mechanical indexes,P_s,g,jand c of main physical and mechanical properties such as soil index of raw data preprocessing,and then to carry on the fitting,CPT the summary is about the Hefei area than penetration resistance and soil physical and mechanical parameters of empirical formulae.In this paper,the static contact data and bearing capacity data of main soil layers in Hefei area are analyzed,single parameter and double parameter fitting are adopted respectively,and the empirical relationship of the natural foundation bearing capacity of typical strata in Hefei area is obtained by using the static contact data.At the same time,according to the collected data and data,the formula for estimating the bearing capacity of precast concrete piles in the code is simplified appropriately,and the formula for estimating the bearing capacity of precast concrete piles using CPT is obtained in Hefei area.The research results have important guiding significance for engineering geological investigation of all kinds of projects in Hefei area and positive significance for engineering application research of CPT.