天津港填海造陆区地震场地效应分析

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关键词场地效应；填海造陆区；H/V方法

中图分类号：P315.9 文献标识码：A 文章编号：2096-7780（2025）09-0507-07

doi：10.19987/j.dzkxjz.2024-073

Analysis of seismic site effects in the Tianjin port sea reclamation region

Cao Fuyang1，Bi Jinmeng1，，Tan Yipeil， Guo Wei

Tianjin Earthquake Agency， Tianjin ， China

Institute of Geophysics， China Earthquake Administration，Beijing 1ooo81， China

AbstractTo beter analyze the seismic site efects in land reclamation areas and provide a scientific basis for earthquake-resistant engineringdesign，thisstudyinvestigates theDongjiangportlandreclamationarea inTianjin. Integrated short-period flow seismometers wereused tocollct ground motion noise atthe site，andtheconsistencyof horizontal-to-vertical （H/V）spectral ratio peaks was analyzed using noise level and H/Vratio methods.Based on longterm observations at fixed points for 26 days，ground motion noise wasrecorded，and a normalized profile map was generated by converting the H/V curve data using a formula based on dominant frequency and depth.The analysis revealed unstable H/V peak values in the low-frequency range below depths of 50～200m ， suggesting that weak wave impedace interfaces caused by backfillsoil exist inthe shallowsubsurface，with relatively distinctsoft sediment interfaces near depths of 50～200m . The dominant frequencies at the site range of 0.6～1.6Hz ，with amplification factors of 1.96～3.99 . This study provides a useful reference for estimating site efects in the Dongjiang port land reclamation area.

Keywordssite effect; sea reclamation region; H/V method

0 引言

场地效应是指场地的地下介质对地震波的放大或衰减影响[1，由于地下土层、岩体以及复杂的地质构造体具有不均匀性和不连续性，场地可以看成一个滤波器，它能够对不同大小和周期的波进行影响，造成不同程度的放大或缩小甚至是滤除[2]。（剩余10062字）