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The proposed study is to investigate the soil dynamic
propertiesof Peitou region in Taipei Basin have been performed
by in-situ testsand Laboratory tests. In-situ tests include
Standard Penetration Test(SPT),Crosshole Seismic Test and
Seismic Cone Penetration Test(SCPT).Laboratory tests have been
performed by using cyclictriaxial test devices. These devices
can accurately measure soil dynamic properties within a wide
strain range of the order 0.0000056to 0.05.The test samples
retrieved by piston tube sampler to produce a lesser degree of
disturbance. Testing results indicate the effects of void
ratio, effective confining stress and over consolidation ratio
on maximum shear modulus are important. The clay of Peitou
region can be expressed as the formula. The laboratory-
obtained maximum shear modulus to coincide with the maximum
shear modulus which has been calculated from Crosshole Seismic
Test .It shows low degree of disturbance. The shear wave
velocity meassured in situ in Peitou region is more lower than
the shear wave velocity calculated from the past empirical
formulas . The shear wave velocity can be expressed as the
formulas.Effects of void ratio, the number of cycles and over
consolidationratio on the strain-dependent shear modulus and
strain-dependent damping ratio are least, but effective
confining stress and plasticity index are significant. An
attempt is made to model the behavior of this soils based on the
test results by five types of models,that accord to Masing-Rule.
It shows that Hyperbolic-secant model and Ramberg-Osgood model
are the best simulate models.
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