四川龙门山地区阳新组灰岩地质特征及用途     

刘亮  韩洪明  杨鹏涛  杨宇东  戴元  陈娜  许涛 《地质与资源》1992,28(5):448-453

二叠系阳新组灰岩厚度240~350 m，走向延伸大于50 km，出露面积15 km²以上，资源储量极为丰富.研究区0.6 km²范围内资源量为5193×10⁴ t.阳新组灰岩CaO含量49.87%~55.74%，MgO含量0.24%~2.80%，SiO₂含量0.38%~5.80%之间，SO₃含量0.01%~0.40%，K₂O+Na₂O含量0.02%~0.12%，均达到Ⅰ级水泥用料要求.饱和抗压强度41.6~82.4 MPa，坚固性1%~3%，压碎指标8.2%~9.6%；所有指标均符合建筑石料用要求.对阳新组灰岩地质特征、物理化学指标的分析评价显示，其可广泛运用于水泥、建筑石料等领域，具有重要的经济价值和意义.  相似文献   

上海地区村镇民房震害预测方法探讨——以宝山区(Ⅵ度)震害预测为例     

陈绍福  何越教 《上海国土资源》1992,(2)

本文通过对上海地区地震危险性分析,论述了上海地区开展村镇民房震害预测的必要性。根据上海地区的建筑特点,并以宝山区Ⅵ度震害预测为例,对上海地区村镇民房震害预测方法的可行性进行了探讨。  相似文献   

On the propagation of an in-plane shear fault with super-S-wave velocity     

Shi-Yu Li  Yun-Tai Chen 《地震学报(英文版)》1993,6(2):335-341

The speedv, especially the problem whether super S-wave velocity in the classical model (linear elasticity fracture mechanics) exists, of spontaneous propagation of a shear fault is investigated theoretically. An in-plane shear crack propagating in the crack plane is taken as the model of the shear fault. The results obtained firstly by Kostrov (1975) is extended from sub-Rayleigh wave velocity to super S-wave velocity, and the analytical expression for the stress intensity factorK ₂ in the case ofα>v>β is derived. It is proved that for Poisson mediumK ₂ is positive and real in the velocity range (β, 1.70β). This demonstrates that (β, 1.70β) is the velocity range which fulfils the conditions for spontaneous crack propagation. The existence, convergence and positiveness or negativeness ofK ₂ forv in individual sections are examined, and it is found that for an in-plane shear crack: 1. There are three sections forv, i.e., [0.v _R], (β, 1.70β), andα, respectively, and 2. There are two physically reasonable sections forv, the first is [v _R, β], and the second is [1.70β, α]. These two forbidden sections behave as barriers to fault propagation. The analytical expressions derived in this paper are not only suitable to classical model, but also to the other derivative models (e. g., the slip-weakening model and the renomalization model etc.). The model considered in this paper is more realistic than the static model employed by previous authors. The Chinese version of this paper appeared in the Chinese edition ofActa Seismologica Sinica, 15, 9–14, 1993.  相似文献   

嘉峪关光化楼残损变形现状及抗震性能分析     

巴振宁  焦鹏  张龙  刘冰松  张翔 《震灾防御技术》2020,15(2):293-304

中国木结构建筑是我国宝贵的物质文化遗产和文化瑰宝，具有悠久的文化历史。以嘉峪关光化楼为依托，对光化楼进行实地调研，分析光化楼主要残损变形。采用ANSYS软件建立考虑光化楼残损变形的三维有限元精细模型，并进行模态分析与时程分析。研究结果表明，光化楼主要残损变形为油饰脱落、墙体剥蚀开裂、柱偏移等，极个别柱产生较大偏移；光化楼刚度相对稳定，前20阶振型自振频率均在10Hz以内；光化楼动力放大系数与层间位移角均较小，仍具有良好的抗震减震性能。  相似文献   

Synthetic Experiments Dealing with Anisotropic Model Building     

Bakker  P. M. 《Studia Geophysica et Geodaetica》2002,46(4):773-792

It has been shown in the past that the interval-NMO velocity and the non-ellipticity parameter largely control the P-wave reflection time moveout of VTI media. To invert for these two parameters, one needs either reasonably large offsets, or some structure in the subsurface in combination with relatively mild lateral velocity variation.This paper deals with a simulation of an inversion approach, building on the assumption that accurately measured V _NMO, as defined by small offset asymptotics for a particular reflector, were available. Instead of such measurements we take synthetically computed data. First, an isotropic model is constructed which explains these V _NMO. Subsequently, residual moveout in common image gathers is modelled by ray tracing (replacing real data), along with its sensitivity for changes in the interval-NMO velocity and the non-ellipticity parameter under the constraint that V _NMO is preserved. This enables iterative updating of the non-ellipticity parameter and the interval-NMO velocity in a layer that can be laterally inhomogeneous.This approach is successfully applied for a mildly dipping reflector at the bottom of a layer with laterally varying medium parameters. With the exact V _NMO assumed to be given, lateral inhomogeneity and anisotropy can be distinguished for such a situation. However, for another example with a homogeneous VTI layer overlying a curved reflector with dip up to 30°, there appears to be an ambiguity which can be understood by theoretical analysis. Consistently with existing theory using the NMO-ellipse, the presented approach is successfully applied to the latter example if V _NMO in the strike direction is combined with residual moveout in dip direction.  相似文献   

地震安全性评价和高层建筑的地震动输入   总被引：4，自引：1，他引：3  

杨柏坡  窦立军 《地震工程与工程振动》2000,20(1):35-41

本文根据现行的中国地震烈度区划图中烈度的含义,指出在使用现行“建筑抗震设计规范”时存在的一些问题和与《中华人民共和国防震减灾法》的不协调之处。根据多年参加工程场地地震安全性评价的经验,总结了目前进行地震安全性评价过程中存在的一些问题。文中建议：针对高层建筑进行新的场地分类方法的研究;对高层建筑工程场地作地震安全性评价时,可根据高度的不同,适当简化安全性评价过程。  相似文献   

Pre‐ and post‐test mathematical modelling of a plan‐asymmetric reinforced concrete frame building     

Peter Fajfar  Matja Dol&#x;ek  Damjan Maru&#x;i&#x;  Aurel Stratan 《地震工程与结构动力学》2006,35(11):1359-1379

Pre‐ and post‐test analyses of the structural response of a three‐storey asymmetric reinforced concrete frame building were performed, aimed at supporting test preparation and performance as well as studying mathematical modelling. The building was designed for gravity loads only. Full‐scale pseudo‐dynamic tests were performed in the ELSA laboratory in Ispra. In the paper the results of initial parametric studies, of the blind pre‐test predictions, and of the post‐test analysis are summarized. In all studies a simple mathematical model, with one‐component member models with concentrated plasticity was employed. The pre‐test analyses were performed using the CANNY program. After the test results became available, the mathematical model was improved using an approach based on a displacement‐controlled analysis. Basically, the same mathematical model was used as in pre‐test analyses, except that the values of some of the parameters were changed. The OpenSees program was employed. Fair agreement between the test and numerical results was obtained. The results prove that relatively simple mathematical models are able to adequately simulate the detailed seismic response of reinforced concrete frame structures to a known ground motion, provided that the input parameters are properly determined. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

基于Hough变换的建筑物半自动提取   总被引：1，自引：0，他引：1  

周俊  吉小刚  郑战辉 《测绘科学技术学报》2006,23(5):345-347

提出了一种基于Hough变换的建筑物半自动提取方法.该方法针对由人工给定建筑物的初始角点并通过统计屋顶主方向对Hough变换的搜索范围和搜索角度进行限制,从而稳定快速地提取出屋顶的边缘.然后利用最小二乘的方法对提取出的屋顶边缘进行精确对中,实现了对平顶直角建筑物以及人字形建筑物的有效提取.  相似文献   

高层隔震结构模型双向振动台试验研究   总被引：2，自引：0，他引：2  

付伟庆  丁琳  陈菲  张立鑫 《世界地震工程》2006,22(3):125-130

对一缩尺1∶16比例高宽比为5的橡胶垫隔震结构模型进行了双向地震动输入振动台试验研究。通过输入不同大小和类型的地震波,分析隔震上部结构和隔震支座的地震反应。试验结果表明:隔震上部结构减震效果较好;隔震支座在某些工况下,竖向可进入非线性受拉变形状态,此时的结构存在倾覆危险。试验相关数据的分析可为高层隔震结构设计理论和规范的编制提供试验依据。  相似文献   

应用基础隔震技术的建筑工程造价分析     

郭起剑  姜莹  战松梅 《世界地震工程》2006,22(4):116-120

应用叠层橡胶支座进行基础隔震是目前国内外大力推广的一门建筑抗震新技术。但由于对采用隔震技术后建筑物的工程造价是否会增加缺乏具体的经济技术指标,使得建筑开发商对其推广应用一直持保守态度。选择了位于VIII度区的两个典型工程实例(一例为乙类建筑,另一例为丙类建筑),简要分析了同一建筑物采取不同设计方案(不隔震但抗震设防、隔震使实际设防水平提高、隔震后与未隔震建筑保持相同设防水平等三种不同设计方案)对工程造价的影响及差异。分析数据表明,在同等设防烈度下,基础隔震技术的合理应用可以使被隔震建筑的工程造价与同条件只采用抗震设防的建筑工程造价适当降低。  相似文献