大理岩卸载力学特性的研究   总被引：2，自引：0，他引：2  

吴玉山  李纪鼎 《岩土力学》1984,5(1):29-36

本文针对洞室,矿山边坡等一些工程的岩体应力变化状况,研究三轴卸载试验的应力路径,并提出以储备强度的概念进行资料整理,从而得出了轴、侧应力同时卸载下的岩石变形特性的特殊性.结果表明,用符合于岩体工程应力变化的加载路径来求取岩体的力学特性是十分必要的.  相似文献   

土高压三轴仪及数据自动处理   总被引：1，自引：1，他引：0  

陈尤雯  赵凌  吴玉山 《岩土力学》1988,9(4):75-84

本文较详细地介绍了适于研究深层基础持力层力学特性的大型试验设备——土高压三轴仪。并结合三轴固结不排水试验实例,介绍了系统的自动化全过程(包括数据实时采集、自动处理、结果输出和图表绘制),以及系统的软、硬件等。  相似文献   

钻孔灌注混凝土摩擦桩的荷载传递和测试   总被引：3，自引：1，他引：2  

吴玉山  吕绍兴 《岩土力学》1988,9(2):71-78

在软弱地基和城市高层建筑物地基的工程处理中,钻孔灌注摩擦桩的应用有日益增多的趋势。本文结合其施工特征在理论上分析了灌注摩擦桩的承载机制和荷载传递性能,并以现场工程实例加以说明。同时,本文指出用实测法确定荷载传递规律时还存在着弹性模量、桩径变化等取值问题,须有待进一步研究。尽管如此,笔者认为用现场实测法确定荷载传递规律还是要比其它方法更接近于实际  相似文献   

Research on Regional Crustal Deformation Characteristics Using Displacement Time Series Data of GNSS Reference Stations in Xinjiang     

Li Guirong  Wang Xiaoqiang  Li Jie  Liu Daiqin  Ailixiati Yushan  Chen Li  Li Rui 《中国地震研究》2018,32(3):388-399

Using GNSS data from the Crustal Movement Observation Network of China( CMONOC),and PODAP software which was developed by the Satellite Navigation Institute of Wuhan University,the authors calculated data from 31 GNSS stations from July 1,2011 to December 31,2014,sampling at 30 seconds,and studied regional crustal deformation characteristics. Analysis results showed that in southwestern Xinjiang,the NS movement rate was influenced by Indian plate pushing. Under the blocking effect of the Tarim Basin,the EW movement rate was slightly smaller. In the north Tianshan area,the vertical dimension movement rate was quite different,which shows as a high gradient zone in the combination area between the basin and the mountain. With regards to regional overall characteristics,the authors considered that the intersection region from south Tianshan and Kunlun Mountains was prone to strong earthquakes, especially moderate-strong earthquakes,even more than M ≥ 7. 0 earthquakes. Middle of North Tianshan was the turning point of the vertical movement rate around Bayanbulak,and was also the high gradient zone of vertical movement. The area is also prone to strong earthquakes in the future.  相似文献   

基于GPS的精河M_S6.6地震前地壳变形动态特征研究     

朱治国  秦姗兰  艾力夏提&#;玉山  刘代芹  李杰  陈丽  苏力坦&#;玉散  方伟 《中国地震》2018,34(3):428-434

利用2013~2017年3期GPS观测资料,获得精河6.6级地震前震中附近区域水平运动速率、主应变率、面膨胀率及最大剪应变率,并结合区域构造背景分析该区域变形动态特征。结果表明:震前震中附近区域速度场速率逐渐增大,发震断裂两盘构造运动速率不均,震中附近区域GPS测点的速率和运动方向存在差异,反应了地壳应变能量积累。震中区域主压应变率变化反映出应力调整过程,沿断层走向的张压转换的形变高梯度带、最大剪应变梯度带可为地震预测提供参考。  相似文献   

上部结构与基础隔震层偏心对结构地震响应的影响          下载免费PDF全文

周力强  王玉山  王迪 《地震工程学报》2020,42(3):624-628,664

随着基础隔震技术的发展,我国在高烈度地区广泛开展基础隔震技术的工程应用必将成为一种趋势,但由于建筑功能和建筑造型的丰富多彩,结构的质量中心和刚度中心也趋于分布不均匀,以三层的钢框架结构为分析模型,利用结构分析软件Sap2000对上部结构质量中心和隔震层质量中心、刚度中心分布不均匀的三种方案进行单向水平地震作用下的非线性时程分析,分析结果表明:上部结构质量中心与隔震层质量中心存在偏心距对结构的扭转效应以及地震响应有较大的影响,减小上部结构的偏心距对调整结构的水平地震响应的影响成效最为显著;对于隔震层而言,隔震层的刚度中心偏心距较质量中心偏心距对上部结构的影响更大,有效控制隔震层刚度中心的偏心距在隔震设计中会更加有效。  相似文献   

Interactive 3D forward modeling of total field surface and three-component borehole magnetic data for the Daye iron-ore deposit (Central China)   总被引：1，自引：0，他引：1  

Yushan Yang  Yuanyuan Li  Tianyou Liu  Yinglin Zhan  Jie Feng 《Journal of Applied Geophysics》2011,75(2):254-263

The ground magnetic response of deep ore bodies in the Daye iron-ore deposit is relatively weak, and sometimes concealed by the strong magnetic background of shallower sources. Apart from the low-quality ground magnetic data, another critical problem for reconstructing the deep skarn-type ore bodies is developing a versatile inversion scheme that can simultaneously resolve 3D sources with arbitrary shapes. In this case, we resort to interactive 3D forward modeling solution with the joint use of two data sets-total field surface and three-component borehole magnetic data. Joint inversion of the two data sets is expected to help resolve the ambiguity associated with either data set and greatly reduces the nonuniqueness of the magnetic inversion. Such nonuniqueness is especially severe when a 3-D distribution of magnetic susceptibility, instead of a simple body, is sought from the inversion.In this paper, we calculate the magnetic field on the surface and in the borehole caused by 3D arbitrarily-shaped bodies with the triple integral method. The complex 3D magnetic sources having arbitrary shapes are constructed with cross-sections, termination points and facets in our visualization technology. We specify, interactively and in a user-friendly environment, the outline of the sources in terms of geometric elements and their magnetic parameters. The method automatically fits the observations within a prescribed precision. If dissatisfied, the user can redefine the model parameters and proceed to a new inversion. The method's ability to interpret a complicated 3D geologic environment is demonstrated on synthetic models and real data profiles in the Daye iron-ore deposit in central China. The interactive forward modeling results in all tests demonstrate a good correlation of estimated magnetic sources with corresponding known geologic features.  相似文献   

Lithospheric Structure in the North China Craton Constrained from Gravity Field Model(EGM 2008)     

李媛媛  杨宇山  Timothy M Kusky 《中国地质大学学报(英文版)》2011,(2)

A detailed knowledge of the thickness of the lithosphere in the North China craton(NCC) is important for understanding the significant tectonic reactivation of the craton in Mesozoic and Ce-nozoic.We achieve this goal by applying the newly proposed continuous wavelet transform theory to the Gravity Field Model(EGM 2008) data in the region.Distinct structural variations are identified in the scalogram image of profile Alxa-Datong(大同)-Qingdao(青岛)-Yellow Sea(profile ABC),trans-versing the main units of NCC,whi...  相似文献   

长条带卫星线阵影像区域网平差研究   总被引：2，自引：0，他引：2  

程春泉  邓喀中  孙钰珊  李小涛 《测绘学报》2010,39(2)

首先比较基于轨道参数和基于卫星状态矢量的航天影像定位轨道模型,提出一种针对非精密星历数据的轨道拟合与状态矢量插值方法,并在飞行坐标系中建立适合长条带卫星影像定位的轨道修正模型。其次,分析地球自转对卫星线阵影像严密定位建模的影响,通过对姿态航偏角的适应性处理,直接在地固地心直角坐标系中建立了基于卫星状态矢量的航天线阵影像构像方程和区域网联合平差模型。论文以中国西部测图工程的塔里木盆地4对(8景)SPOT5/HRS长条带立体影像为数据源,针对不同控制点数目与分布,进行了不同方案的组合定位试验。结果表明:稀少控制点条件下检查点统计精度达到了8.09m。  相似文献   

资源三号卫星影像无控制区域网平差   总被引：3，自引：1，他引：2  

孙钰珊  张力  许彪  张勇 《遥感学报》2019,23(2):205-214

国产高分辨率光学卫星影像的无地面控制精准定位是实现境外大范围区域或大规模遥感应用和中小比例尺测图的前提。针对资源三号卫星(ZY-3)影像的几何特点,以航空摄影测量中约束问题最优化方法"交替趋近法"和基于RFM的最小二乘平差为基础,提出了一种易于并行化、高效的高分辨率光学卫星影像无控制联合区域网平差方法GISIBA(GCP-Independent Satellite Imagery Block Adjustment),通过构建"平均值"虚拟控制点来解决无控制区域网平差中的"秩亏"问题,便于分析无控制区域网平差结果与影像数据的覆盖次数及时相之间的关系。首先,交替趋近法被用来实现并行处理平台基础上的待平差未知数初值的解算、中等尺度以上粗差的自动检测与剔除,并根据计算结果赋予所有未知数一定的先验权值;然后,通过最小二乘法实现大型法方程矩阵的解算,获得满足高精度影像产品生产制作需求的高精度定向参数;最后,利用多组典型区域的ZY-3影像数据试验验证了该方法的精度和实际性能。结果表明,无控制区域网平差达到了优于6.0 m/5.0 m的平面/高程精度,所提方法为全球地理信息资源建设工程、国产光学卫星影像高精度影像产品生产提供了技术保障。  相似文献