沿江与沿桥城市发展对比研究     

赵一如  姚建华 《地域研究与开发》2000,19(3):21-25

沿江产业带和沿桥经济带同是横跨我国东、中、西三大地带的经济建设的的级轴线,其城市经济发展状况存在很大差异。文章通过对二者的城市等级规模、空间结构、城市化程度及积能结构等方面进行具体的差异比较,对导致才者差异的主观及客观原因进行深入分析,提出了几点适合陆桥知身特点,结合陆桥现有机遇的具体建议。  相似文献   

遥感技术在亚欧大陆桥(哈密-阿拉山口段)沿线地质灾害调查中的应用研究     

吴健生  周正武 《国土资源遥感》1998,9(4):82-85

利用遥感技术对亚欧大陆桥的新疆哈密—阿拉山口沿线一带的地质灾害类型、特点,发生的地质地貌背景、气候水文环境和激发因素以及分布规律等进行系统的分析,划分了地质灾害类型和组合分区,并提出初步评价和防治建议,为国家和地方防灾、减灾规划提供重要的遥感资料和依据。  相似文献   

新亚欧大陆桥与新疆矿产资源开发的初步研究   总被引：1，自引：0，他引：1  

金海龙 《干旱区地理》1996,19(1):17-20

本文通过对新亚欧大陆桥国内段、中亚段、东欧段及西欧段矿产资源优劣的分析，提出了新亚欧陆桥贯通形热下新疆矿产资源合理开发利用的对策。  相似文献   

亚欧大陆桥与青海旅游业     

张忠孝  朱丽东 《干旱区地理》1996,(1)

在简述亚欧新陆桥在我国境内基本概况及旅游潜力估价的基础上，从青海旅游资源特征出发，探讨了青海旅游业在新陆桥中国旅游业中的特殊地位及青海旅游业发展在青海经济开发中的战略意义．  相似文献   

古丝绸之路与新亚欧大陆桥：河西走廊经济发展思考     

姚建华  郎一环 《干旱区地理》1996,19(1):10-13

河西走廊在古丝绸之路中占有重要的地位和作用。新亚欧大陆桥开通之后，河西能否依桥再现辉煌，必须从古丝路与新陆桥的特点出发，作对比研究。本文分析了沿海和沿桥的历史特点与现状，提出了河西经济发展应采取的积极主动对策，即主动上桥、逼桥赐惠；人车分离与千方引客；西进东出、走出封闭。  相似文献   

珠江黄埔大桥模态频率连续监测中的温度影响Ⅰ:频率识别   总被引：2，自引：2，他引：0  

朱嘉健  王立新  姜慧  赵贤任  李雪艳 《震灾防御技术》2016,11(1):67-75

为研究环境温度对珠江黄埔大桥频率监测的影响,首先要对大桥模态频率进行连续识别。珠江黄埔大桥上架设的监测系统为强震动台阵,相较于其他健康监测系统测点较少,因此,应基于强震动台阵系统的特点,选取合适的方法对大桥频率进行识别。本文通过对比分析平均正则化功率谱法(ANPSD)、频域分解法(FDD)和协方差驱动的随机子空间法(Cov-SSI)的识别结果,择优应用于珠江黄埔大桥的频率自动识别中。采用珠江黄埔大桥强震动台阵记录的2013年4月至11月加速度响应数据进行频率识别,识别结果可用于观测和研究大桥频率在环境影响下的波动情况。  相似文献   

Evaluation of substructuring method for seismic soil-structure interaction analysis of bridges     

《Soil Dynamics and Earthquake Engineering》2016

This paper evaluates the commonly used substructuring method for analysis of bridge systems where the bridge is divided into two sub-systems: the bridge superstructure and the substructure including the pile foundations, abutments, and soil. Modeling of the soil-structure interaction (SSI) in the system is simplified by replacing the pile foundations, abutments, and soil with sets of independent equivalent linear springs and dashpots at the base of the superstructure. The main objective of the paper is to examine how well the substructuring method simulates the seismic response of a bridge system. The baseline data required for the evaluation process is derived from analyzing a fully-coupled continuum bridge model, already validated for the instrumented two-span Meloland Road Overpass. The same bridge system is also simulated using the substructuring method. The results from both approaches are compared, and it is shown that the differences between them can be significant. The substructuring method consistently overestimates the pier base shear forces and bending moments and the pier top deflections. Moreover, the spectral response of the bridge structure is mispredicted. The analyses are repeated for a three-span bridge system subjected to several ground motions, leading to a similar observation as before. Hence, the current state of practice for simulating seismic SSI in bridges using the substructure model is shown to be too simplified to capture the major mechanisms involved in SSI.  相似文献   

长江口沙波分布区桥墩局部冲刷深度计算公式的改进   总被引：1，自引：0，他引：1  

王冬梅  程和琴  李茂田  周丰年  吴敬文  杨忠勇 《海洋工程》2012,30(2):58-65

利用多波束水深仪、浅地层剖面仪和多普勒流速仪对长江口苏通大桥南、北主墩区域现场测量,结果显示主墩周围最大冲刷深度为8.3 m和19.6 m。建墩前后河床形态变化显著,建墩后桥墩所在床面由平床改变为典型不对称沙波发育,平均波长为30.8 m和23.1 m,平均波高为4.2 m和9.4 m,陡坡朝向下游。基于实测水文条件和地形资料,以沙波起动流速和落急最大流速分别取代单向流作用下"平床"假定的桥墩局部冲刷计算公式中单颗粒泥沙的起动流速和墩前流速,获得河口涨落潮双向流作用下沙波底床桥墩局部冲刷计算公式。且该公式计算的苏通大桥南、北主墩局部冲刷深度为9.5 m和22.1 m,非常接近实测值。  相似文献   

近场下桥梁结构的地震响应分析     

王昊  谭平  殷伟希  周福霖 《华南地震》2010,30(2):8-14

提出采用宽频地震Kanai-Tajimi模型与速度脉冲He-Agrawal模型来模拟近场地震动,数值模拟验证了该近场地震模型的有效性。采用该模型定量分析了近场地震作用对桥梁结构地震响应的影响规律。近场地震动的脉冲持时是对结构产生破坏的一个重要因素,近场地震作用对桥梁结构的设计提出了更高的延性要求。  相似文献   

A critical review of methods for pile design in seismically liquefiable soils   总被引：1，自引：0，他引：1  

S. Bhattacharya  S. P. G. Madabhushi 《Bulletin of Earthquake Engineering》2008,6(3):407-446

Collapse and/or severe damage to pile-supported structures are still observed in liquefiable soils after most major earthquakes. Poor performance of pile foundations remains a great concern to the earthquake engineering community. This review paper compares and contrasts the two plausible theories on pile failure in liquefiable soils. The well established theory of pile failure is based on a flexural mechanism; where the lateral loads on the pile (due to inertia and/or lateral spreading) induce bending failure. This theory is well researched in the recent past and assumes that piles are laterally loaded beams. A more recent theory based on buckling instability treats the piles as laterally unsupported slender columns in liquefiable soils and investigates the buckling instability (bifurcation). The objective of this paper is to investigate the implications to practical pile foundation design that flow from both these theories. Provisions for design made by major international codes of practice for pile design including the Japanese Highway Code (JRA) will be considered. The necessity for such codes to consider alternative forms of failure mechanisms such as the buckling instability of piles in liquefied ground will be discussed. S. Bhattacharya–Previously Departmental Lecturer in Engineering Science, University of Oxford, UK and Fellow of Somerville College, Oxford. S. P. G. Madabhushi–Fellow of Girton College, Cambridge.  相似文献