Development and field application of static cone penetrometer combined with dynamic penetration

New type static cone penetration equipment called combination cone was developed for more appropriate evaluation of housing land bearing capacity. The combination cone penetration equipment installs dynamic penetration mechanism to increase cone penetration power, but does not attach the pore water pressure measurement function to promote the efficiency of the work. To establish the bearing capacity evaluation method with high reliability from the combination cone penetration test result, the in-situ experiment of combination cone penetration test, plate loading test, three-component cone penetration test and Swedish weight sounding test was executed on a lot of sites in Kanto and Kansai district in Japan. An empirical formula of the bearing capacity was proposed based on this correlation. On the other hand, a good correlation was not obtained between number of half turn Nswof Swedish weight sounding test result and cone resistance qc. Some problems when the bearing capacity was calculated from Swedish weight sounding test result were confirmed. To be obtained higher additional values, the surface wave exploration can be combined with the combination cone penetration test. The surface wave exploration can be obtained the cross section of S-wave velocity corresponding to soil stiffness. The surface wave exploration combined with the combination cone penetration test is very useful in-situ investigation approach for the estimation of the bearing capacity of housing land.