HowNet Based Chinese Question Classification

PACLIC 20 / Wuhan, China / 1-3 November, 200

<i>V</i>_s30 Prediction Models Based on Measured Shear-Wave Velocities in Tangshan, China

Vs30 (equivalent shear-wave velocity of soil layers within a depth of 30 m underground) is widely used in the field of seismic engineering; however, due to the limitation of funds, time, measuring devices, and other factors, the depth for testing shear-wave velocity in an engineering site rarely reaches 30 m underground. Therefore, it is necessary to predict Vs30 effectively. We analyzed the existing models using 343 boreholes with depths greater than 30 m in Tangshan, China. It shows that the topographic slope method is not suitable for predicting Vs30 in Tangshan. The Boore (2011) model overestimates, while Boore (2004) underestimates Vs30 in Tangshan, while Junju Xie’s (2016) model has ideal prediction results. We propose three new models in this paper, including the bottom constant velocity (BCV) model, linear model, and conditional independent model. We find that the BCV model has limited prediction ability, and the linear model is more suitable when z ≤ 18 m, while the conditional independent model shows good performance under conditions where z > 18 m. We propose that the model can be accurately and effectively applied in Tangshan and other regions with low shear-wave velocity

Effect of Different Groundwater Levels on Seismic Dynamic Response and Failure Mode of Sandy Slope

<div><p>Heavy seismic damage tends to occur in slopes when groundwater is present. The main objectives of this paper are to determine the dynamic response and failure mode of sandy slope subjected simultaneously to seismic forces and variable groundwater conditions. This paper applies the finite element method, which is a fast and efficient design tool in modern engineering analysis, to evaluate dynamic response of the slope subjected simultaneously to seismic forces and variable groundwater conditions. Shaking table test is conducted to analyze the failure mode and verify the accuracy of the finite element method results. The research results show that dynamic response values of the slope have different variation rules under near and far field earthquakes. And the damage location and pattern of the slope are different in varying groundwater conditions. The destruction starts at the top of the slope when the slope is in no groundwater, which shows that the slope appears obvious whipping effect under the earthquake. The destruction starts at the toe of the slope when the slope is in the high groundwater levels. Meanwhile, the top of the slope shows obvious seismic subsidence phenomenon after earthquake. Furthermore, the existence of the groundwater has a certain effect of damping.</p></div

Characteristics of seismic waves.

<p>Characteristics of seismic waves.</p

Physical parameters of slope.

<p>Physical parameters of slope.</p

Basic earthquake acceleration value.

<p>Basic earthquake acceleration value.</p

Test results of the frequencies.

<p>Test results of the frequencies.</p