Identification of the Hualien soil-structure interaction system

This article demonstrates how system identification techniques can be successfully applied to a soil-structure interaction system in conjunction with the results of the forced vibration tests on the Hualien large-scale seismic test structure which was recently built in Taiwan for an international joint research. The parameters identified are the shear moduli of several near-field soil regions as well as Young's moduli of the shell sections of the structure. The soil-structure interaction system is represented by the finite element method combined with infinite element formulation for the unbounded layered soil medium. Preliminary investigations are carried out on the results of the static stress analysis for the soil medium and the results of the in-situ tests to divide the soil-structure system into several regions with homogeneous properties and to determine the lower and upper bounds of the parameters for the purpose of identification. Then two sets of parameters are identified for two principal directions based on the forced vibration test data by minimizing the estimation error using the constrained steepest descent method. The simulated responses for the forced vibration tests using the identified parameters show excellent agreement with the test data. The present estimated parameters are also found to be well compared with the average value of those by other researchers in the joint project.     

厄尔尼诺海区海温季节预测比较

利用奇异值分解方法建立多项线性统计气候预测模型,对厄尔尼诺海区各季节海温进行了短期气候预测试验,并采用历史资料独立样本检验的方法,评定不同预报时效的预报技巧。结果表明,不同海区各季节的预报效果相差很大。赤道西太平洋（ Ｎｉｎｏ ４区）有最高的可预报性,在夏季末做冬季海温预报的技巧最高,多数条件下,这个区域的预报性能比较稳定。以海温和南方涛动指数作因子场的预报效果最好,大部分预报以单季的海温和南方涛动指数为预报因子效果较好,但有些预报以连续２季或３季的海温和南方涛动指数作预报因子的预报效果更好。     

金成矿作用过程中金钯的浸滤实验研究

研究表明,Ａｕ、Ｐｄ在含矿热液体系中地球化学性质明显不同。Ａｕ活性显著,Ｐｄ惰性特征明显;二者都偏向溶于碱性介质（Ｐ＝１００×１０５Ｐａ、Ｔ＝２００℃）;在温度为１００℃或压力为１００×１０５Ｐａ时有利于金的溶解、活化迁移;而金成矿的最佳物化环境是温度２５０℃、压力２０×１０５～３０×１０５Ｐａ、ｐＨ＝７．５６左右。     

钢屈服—摩擦复合耗能器的性能研究

本文提出了“综合利用不同耗能原理和机制来设计新型耗能器”的思想,研究开发了钢屈服－摩擦复合耗能器,并对其进行了性能试验和对比试验,考察了耗能器的工作性能和耗能性能。给出了耗能器的恢复力模型,研究结果表明,钢屈服－摩擦复合耗能器利用钢屈服滞回和摩擦两种机制耗能,具有稳定的工作性能,耗能能力强且可调节,构造简单,形状紧凑,体积小,造价低,制作与安装方便,是一种有广阔应用前景的新型耗能减震装置。     

川—20地下水综合观测井井下仪器探头相互干扰的现场实验研究

给出了川- 20 地下水综合观测井井下仪器探头可能存在机械部分相互干扰的现场研究结果。所得结果对于正确区分各种手段今后的异常与干扰具有参考意义。     

岩石多次全过程压入硬度的测试试验

介绍了在ＭＴＳ８１５型岩石力学试验机上配置专用夹具和平底圆柱压模后成功地进行岩石表面多次全过程压入破碎试验的情况,分析了这种试验方法与传统的单次压入硬度测试法相比在反映岩石破碎过程特征、表征岩石压入硬度方面所具有的优点。最后邮进一步研究应解决的几个问题。     

实验室声发射三维定位及标本波速场各向异性研究

根据慢度离差法的基本原理,给出由遗传算法确定AE空间位置、发生时刻及慢度离差5个参量的具体方法。结合实验条件,通过数值试验对定位误差等问题进行探讨,并对真实AE定位的误差分布给出统计上的圈定。数值试验结果表明,算法具有较高的精度和较好的收敛性及稳健性;探头数量及布设方式对定位结果的优劣有影响, 4个以上探头有记录时,即可得到理想的结果;大的定位误差主要来源于台阵外部少数“ AE”的结果。到时测量的随机误差小于最小测量时间单位的50%时,平均有97%的“AE”定位误差分布在3 mm 范围内,小于物理不可分辨精度(探头直径)。     

Regional seismicity triggered by the Hyogo-Ken Nanbu, Japan, M =7.2 earthquake on January 17, 1995

The time and spatial feature of the regional seismicity triggered by the Hyogo-Ken Nanbu, Japan, M=7.2 earthquake on January 17,1995, was studied. The concerned region is about several hundred kilometers in length and breadth surrounding the epicenter (33°～37°N, 133°～138°E). It is divided into 16 subregions. The seismicity of these subregions from January of 1976 to June of 1996 has been analyzed. It is showed that,① there were significant seismicity changes in 10 subregions triggered by the Hyogo-Ken Nanbu, Japan, M=7.2 earthquake on January 17, 1995. These changes passed a Z statistic test exceeding 0.95 confidence level and the greatest epicenter distance of these subregions was 280 km;②seismicity changes were triggered within 1～5 days in three subregions near the main shock while in other subregions the seismicity changes were triggered within several ten days after the main shock;③ the greatest triggered event is 5.4, which is about the same size as the greatest aftershock;④the regional stress change resulted from the main shock may be the triggered mechanism of the regional seismicity.     

桶形基础沉贯室内模型试验研究

桶形基础采用负压沉贯法施工,其贯入阻力与压桩,打桩等施工方法显著不同。本文介绍了在粉土和粉质粘土地层中的一组模型试验情况,认为负压法施工可显著降低粉土的抗贯阻力,但在粉质粘土中减阻效果不明显。     

玻璃钢渔船总纵弯曲的实船试验研究

本文通过实船试验研究玻璃钢渔船的总纵弯曲,以求得玻璃钢渔船应变和挠度随载荷的变化特性,从而了解玻璃钢渔船的总纵强度。