Shake table testing of a multi-tower connected hybrid structure

Many single-tower reinforced concrete core wall-steel frame (RCC-SF) buildings have been built in China, but there are no buildings of different-height multi-tower hybrid system. A multi-tower RCC-SF tall building was thus studied because of its structural complexity and irregularity. First, a 1/15 scaled model structure was designed and tested on the shake table under minor, moderate, and major earthquake levels. Then, the dynamic responses of the model structure were interpreted to those of the prototype structure according to the similitude theory. Experimental results demonstrate that, despite the complexity of the structure, the lateral deformation bends as the "bending type" and the RC core walls contribute more than the steel frames to resist seismic loads. The maximum inter-story drift of the complex building under minor earthquakes is slightly beyond the elastic limitation specified in the Chinese code, and meets code requirements under major earthquakes. From the test results some suggestions are provided that could contribute favorable effect on the seismic behavior and the displacement of the building.     

汶川8.0级地震前后全国倾斜场变化初步分析

由于岩石介质的不均匀型,在易破区域会出现应力积累,伴随着倾斜会出现较大的变化。由岩石破裂实验可以看出破裂区在破裂前出现了体积变大（鼓包）或变小（凹坑）现象,如果在岩石表面放置倾斜仪器,我们不难得出各仪器的倾斜方向指向或背向破裂点。本文采用全国前兆台网地倾斜（水管）数据,使用5次曲面函数区域插值的方法,拟合出地倾斜场（图1）。     

Organic Acid Derivatization Techniques Applied to Petroleum Hydrocarbon Transformations in Subsurface Environments

Evidence for the natural microbial remediation of subsurface fuel contamination situations should include identification and analysis of transformation or degradation products. In this way. u mass balance between fuel constituents and end products may be approached to monitor cleanup progress. Application of advanced organic acid metabolite derivatization techniques to several known sites of organic compounds and fuel mixture contamination provide valuable information on the pathways and progress of microbial transformation. Good correlation between observed metabolites and transformation pathways of aromatic fuel constituents were observed at the sites.     

台湾琉球地区Lg波的震相特征

根据浙闽台站记录的台湾琉球近震资料，研究了该区Ｌｇ波的组成及各震相的基本特征。研究表明，该区Ｌｇ波由多个速度不同的波群组成，在Ｌｇ１和Ｌｇ２两种波中可以分出Ｌｇ′１、Ｌｇ″１；和Ｌｇ′２、Ｌｇ″２四种震相，不同震区各震相的记录特征明显不同，鲜明地反映出地壳结构由大陆型向海洋型过渡的特点。此外，还对波列中的未知震相、影响震相记录特征的其它因素，以及震相标注和Ｌｇ波走时表等问题进行了讨论。     

Determination of the degree 120 time-variable gravity field in the Sichuan-Yunnan region using Slepian functions and terrestrial measurements

The terrestrial time-variable gravity measurements are characterized by a high signal-to-noise ratio and sensitivity to the sources of mass change in the Earth's crust. These gravity data have many applications, such as surface deformation, groundwater storage changes, and mass migration before and after earthquakes. Based on repeated terrestrial gravity measurements at 198 gravity stations in the Sichuan-Yunnan region (SYR) from 2015 to 2017, we determine a time series of degree 120 gravity fields using the localized spherical harmonic (Slepian) basis functions. Our results show that adopting the first 6 Slepian basis functions is sufficient for effective localized Slepian modeling in the SYR. The differences between two gravity campaigns at the same time of year show an obvious correlation with tectonic features. The degree 120 timevariable gravity models presented in this paper will benefit the study of the regional mass migration inside the crust of the SYR and supplement the existing geophysical models for the China Seismic Experimental Site.     

单一地震事件与多个地震事件的定位方法及应用

主要介绍各种地震定位方法,概述各种地震定位方法的基本原理,重点介绍Geiger的经典方法以及在此基础上建立的各种线性方法:单一地震事件定位法与多个地震事件定位法以及对每一种地震定位方法的应用情况,尤其是国内的应用情况做了总结;同时指出各种方法的特点,并进行相应的比较.     

广东沿海地区现代地壳垂直运动研究

对３０多年来１万多ｋｍ精密水准复测数百个重合点资料进行了综合研究，结果表明，广东沿海岸段的地壳平均以－０．５ｍｍ／ａ幅度沉降，表现出粤西抬升，粤东沉降，珠江三角洲大面积下沉的格局。粤西岸段平均以＋０．６ｍｍ／ａ速率上升，粤东沿海岸段平均以－０．７ｍｍ／ａ速率下降；珠江三角洲以－１．８ｍｍ／ａ速率下沉，桂东南岸段则以＋３．４ｍｍ／ａ的速上升。     

新疆南天山环境应力场特征

基于新疆强震固定台和流动观测记录的主要和余震加速度资料，选用了三个分向记录都完整的３７次地震。震级范围为１．８－６．８级，震中距为几至几十公里。根据用位错理论二维断裂力学模式推导的震源峰值、加速度与环境剪应力场关系式计算了新疆南天山环境剪应力值。计算结果表明，新疆南天山环境应力平均值偏高，这与新疆处于特殊构造环境条件有关。     

变刚度钢管混凝土短柱隔震装置的性能研究

本文对变刚度钢管混土短柱震的滞回收性进行了理论分析和试验验证。对装置的隔震作用以及耗能特性进行了讨论通过低周反复荷载试验,证了分析的正确性。同时,试验还证明,变刚度钢管混凝土短柱震装置能很好的地耗散能量,从而减小地震反应,作者认为,该是一种价格性能比较优越的隔震装置,在工程实践中将有广阔的应用与推广前景。     

北天山重点监视区地下流体临震前兆标志探讨

在“八五”短临预报和“九五”中短期（１年尺度）前兆研究的基础上,运用整点值、日测值、原始曲线法、一阶差分法和日工法,系统地分析了北天山１９８５年以来的地下流体前兆观测资料,研究了在此期间控制区范围内发生的７次Ｍs５.０级以上中强地震前临丑异常显示特征,探索了中强地震发生前地下流体临震前兆标志,表明只要正确地识别地震前兆的中长期向中短期、短期、临震前兆过渡的标志,并进行短临跟踪,是可以实现临震预报的。