|
|||||
|
|
The contribution of the built environment to the ‘free-field’ ground motion in Mexico City |
|
| Authors: | Francisco J Chvez-García Martín Crdenas |
| Institution: | a Instituto de Ingeniería, UNAM, Ciudad Universitaria, Apdo. Postal 70-472, Coyoacán, 04510, México City, Mexico b Facultad de Ingeniería, DICT-Geofísica, UNAM, Ciudad Universitaria, Apdo. Postal 70-472, Coyoacán, 04510, México City, Mexico |
| Abstract: | Soil–structure interaction (SSI) effects on building dynamic behaviour have been studied extensively. In comparison, the radiation of waves away from the soil–foundation interface has received little attention. Recent studies point out that SSI in an urban environment can modify the ground motion recorded in the free-field. These modifications will be important when two conditions are met: structures founded on soft soils and coincidence between the vibration periods of the structure and those of the superficial layers. Both conditions are met in Mexico City lake zone. In this study, we investigate SSI effects on ‘free-field’ motion. The data we use consist of microtremors recorded on soft soils in Mexico City, a densely built environment. Our objective was to identify the modifications to free-field ground motion caused by neighbouring structures. Data were analysed using H/V spectral ratios. Large variations in the level of amplification and resonant frequency were determined from microtremors in very closely spaced stations. Our results suggest consistently that free-field ground motion is significantly affected by the presence of neighbouring structures. |
| Keywords: | Soil–structure interaction Microtremors Site effects H/V spectral ratios Radiated wavefield |
| 本文献已被 ScienceDirect 等数据库收录！ | |