標題: Quantitative Interpretation of Surface Wave Testing for Assessment of Ground Improvement by Jet Grouting
作者: Lin, Chih-Ping
Lin, Chun-Hung
Chang, Yu-Cheng
Chien, Chih-Jung
防災與水環境研究中心
Disaster Prevention and Water Environment Research Center
公開日期: 1-Jan-2017
摘要: Jet grouting technique is special in that the ground becomes highly heterogeneous after installing the improvement columns. The surface wave method was recently shown to hold good promise to assess the average property of the improved ground and evaluate the area replacement ratio. Even though the improved ground was highly heterogeneous along the seismic survey line, the surface wave method worked well and yielded a homogenized shear wave velocity profile. The increase of shear wave velocity after ground improvement was found to be correlated with the area replacement ratio. This study further examined the quantitative relation between the percentage increase of shear wave velocity and the area replacement ratio. The effect of offline sampling (perpendicular to survey direction) was also investigated. 3D spectral element method was utilized for the numerical investigation. Numerical results show that the offline sampling range is about 75%-85% of the wavelength. Hence, it should be noted when planning survey lines. Furthermore, a positive correlation between replacement ratio and velocity increase exist and the difference caused by the velocity contrast between soils and improved columns could be neglected as the velocity contrast becomes greater than about 5. An empirical predictive model between the velocity increase percentage and area replacement ratio was established based on the numerical simulations.
URI: http://hdl.handle.net/11536/146736
ISSN: 0895-0563
期刊: GROUTING 2017: JET GROUTING, DIAPHRAGM WALLS, AND DEEP MIXING
起始頁: 73
結束頁: 81
Appears in Collections:Conferences Paper