CAJ | 학술논문

近断层地震动场的预测不仅可以为抗震结构设计提供更加丰富的地震动输入，也可以作为土地合理规划的参考依据。在一些地震活动相对较弱的地区，地震往往发生在两个早第四纪断裂相交的位置处。因此对于这种相交早第四纪断裂区的近断层地震动场预测具有实际的意义。本文以枣庄市新城区为例，预测了在设定地震发生时，相交早第四纪断裂近断层地震动场的分布情况。先分别计算了近断层区低频和高频的地震动，然后将低频和高频成分合成宽频带的地震动场。在计算低频地震动场时，建立了枣庄市新城区地下三维传播介质模型和震源模型。计算的过程是模拟震源发生破裂产生地震波后，地震波在地下介质中的传播过程。使用了三维显式有限元、快速拉格朗日有限元法等数值计算方法以及并行计算技术来提高计算的速度。由于地震动的频率成分是连续的，因此对于高频地震动使用了随机震动理论来进行合成。本文研究的预测结果具备断层附近地震动的一些最基本的特征，符合当前对断层附近地震动的基本认识。
근단층지진동장적예측불부가이위항진결구설계제공경가봉부적지진동수입，야가이작위토지합리규화적삼고의거。재일사지진활동상대교약적지구，지진왕왕발생재량개조제사기단렬상교적위치처。인차대우저충상교조제사기단렬구적근단층지진동장예측구유실제적의의。본문이조장시신성구위례，예측료재설정지진발생시，상교조제사기단렬근단층지진동장적분포정황。선분별계산료근단층구저빈화고빈적지진동，연후장저빈화고빈성분합성관빈대적지진동장。재계산저빈지진동장시，건립료조장시신성구지하삼유전파개질모형화진원모형。계산적과정시모의진원발생파렬산생지진파후，지진파재지하개질중적전파과정。사용료삼유현식유한원、쾌속랍격랑일유한원법등수치계산방법이급병행계산기술래제고계산적속도。유우지진동적빈솔성분시련속적，인차대우고빈지진동사용료수궤진동이론래진행합성。본문연구적예측결과구비단층부근지진동적일사최기본적특정，부합당전대단층부근지진동적기본인식。
Near-fault ground motion field distribution not only provides more abundant seismic inputs, but also can be used as reference for the seismic design and land use planning. In some areas of relatively weak seismic activity, earthquakes tend to occur at the location of the intersection of two early Quaternary faults. The prediction of the near-fault ground motion field distribution at the location of the intersection of two early Quaternary faults has practical significance. As an example,the near-fault ground motion distribution at intersection early Quaternary fault zone of Zaozhuang new City was predicted when a setting earthquake occurred.The high-frequency and low-frequency ground motions were calculated respectively, and were composed to broad-frequency ground motion.1-D equivalent linearization method was used to calculate the broad-frequency ground motion time histories of some special local sites according to survey data. The PGA distribution and the corresponding response spectra of the target region are got according to the ground motion time histories when the design earthquake occurs. The forecasting result has the basic characteristics of near-fault ground motion, and matches the current basic understanding of the ground motion near the fault.