预测较强矿震的地震学方法探讨

用地震学和数理统计方法分析了抚顺老虎台矿28a完整连续的矿震资料，证实了存在两种不同机制的矿震，探讨了可用于较强矿震事件预测的地震学判别方法。     

用CAP方法研究久治-玛曲MS4．1级地震震源机制

选用区域数字地震台网的波形资料,利用CAP方法反演了2011年3月3日久治-玛曲4．1级地震震源机制解。反演结果显示,本次地震的最佳双力偶解为节面Ⅰ走向3060倾角82°、滑动角-5°,节面Ⅱ走向37°、倾角85°、滑动角-172°,地震类型为走滑型,震源深度为5．5km,属于汶川地震后区域应力场调整引发的一次地震事件。     

天然气水合物钻探取样技术现状与研究

通过资料调研与研究,综合分析了国外深海天然气水合物钻探取样工具的结构原理、技术参数、作业过程、主要特点以及对设备的要求等。同时简要介绍了我国“十一五”期间取样装置的研制进展情况。     

新型深孔立轴式回转器的研制

介绍了新型立轴式钻机的回转器与给进装置的结构特点与技术参数,以及产品在项目工地的实际应用情况。产品汲取了国内外全液压动力头的优点,具有给进行程长,维修方便等特点。     

时域激电法单极-偶极装置在广西某金银矿勘查中的应用

文章简述了勘查区广西河池市某金银矿区的地质特征、矿化类型和时域激电单极-偶极布极方式及特点,结合实例说明该装置在确定矿体的形态、产状等空间位置方面有较好的应用效果。     

利用重力资料检测日本9.0级地震激发的地球自由振荡

利用格尔木基准地震台重力观测资料,检测到2011年3月11日日本东海岸9.0级特大地震激发0S0 ～0S40之间的球型自由振荡,其中有0S0、0S13、0S22、0S26、0S30共5个振型的观测频率值与理论频率值偏差近似为0.同时发现0S2、0S3振型有明显的谱线分裂现象,但是0S32、0S37振型未与周围噪音区分开,观测效果不明显.整体平均偏差约为0.10％,观测频率值与理论频率值有很好的相符,这不但说明了PREM模型理论的正确性,也说明了格尔木基准地震台重力资料质量的优良,研究结果对了解地球内部结构有一定的帮助.     

河南洛阳地震台适应数字化时代发展的探索与思考

文章介绍洛阳地震台应对数字化发展,在监测预报、科普宣传、地震应急、科学研究等几方面取得的实践成果,提出台站未来发展的目标。     

哈尔滨延寿地震台竖直摆倾斜观测异常特征初探

哈尔滨延寿地震台属单点观测,能记录到丰富的前兆信息。文章通过对几次地震前台站CZB-1型竖直摆倾斜仪记录数据的异常特征进行分析,探寻倾斜前兆异常与地震的关系。研究发现．在观测点周边350km范围内,延寿台竖直摆倾斜在震前有较好的短期异常显示。     

Seismic performance of cable-sliding friction bearing system for isolated bridges

During past strong earthquakes, highway bridges have sustained severe damage or even collapse due to excessive displacements and/or very large lateral forces. For commonly used isolation bearings with a pure friction sliding surface, seismic forces may be reduced but displacements are often unconstrained. In this paper, an alternative seismic bearing system, called the cable-sliding friction bearing system, is developed by integrating seismic isolation devices with displacement restrainers consisting of cables attached to the upper and lower plates of the bearing. Restoring forces are provided to limit the displacements of the sliding component. Design parameters including the length and stiffness of the cables, friction coefficient, strength of the shear bolt in a fixed-type bearing, and movements under earthquake excitations are discussed. Laboratory testing of a prototype bearing subjected to vertical loads and quasi-static cyclic lateral loads, and corresponding numerical finite element simulation analysis, were carried out. It is shown that the numerical simulation shows good agreement with the experimental force-displacement hysteretic response, indicating the viability of the new bearing system. In addition, practical application of this bearing system to a multi-span bridge in China and its design advantages are discussed.     

Mooring tension and motion characteristics of a submerged fish reef with net in waves and currents using numerical analysis

A numerical model was used to analyze the motion response and mooring tension of a submerged fish reef system. The system included a net attached to a rigid structure suspended up from the bottom with a single, high tension mooring by fixed flotation. The analysis was performed by using a Morison equation type finite element model configured with truss elements. Input forcing parameters into the model consisted of both regular and irregular waves, with and without a steady current. Heave, surge and pitch dynamic calculations of the reef structure were made. Tension response results of the attached mooring line were also computed. Results were analyzed in both the time and frequency domain in which appropriate, linear transfer functions were calculated. The influence of the current was more evident in the tension and heave motion response data. This is most likely the result of the large buoyancy characteristics of the reef structure and the length of the mooring cable. Maximum mooring component tension was found to be 13.9 kN and occurred when the reef was subjected to irregular waves with a co-linear current of 1.0 m/s velocity. The results also showed that the system had little damping (in heave) with damped natural periods of 2.8 s. This combination of system characteristics promotes a possible resonating situation in typical open sea conditions with similar wave periods.