Model on Improved Variable Weight-Matter Element Theory for Risk Assessment of Water Inrush in Karst Tunnels     

Wang  Sheng  Li  Liping  Cheng  Shuai  Liu  Zhenhua  Ding  Ruosong  You  Qiang 《Geotechnical and Geological Engineering》2021,39(5):3533-3548

Geotechnical and Geological Engineering - This paper presents an improved risk assessment model to evaluate the risk of water inrush in karst tunnels based on matter element theory and ideal point...  相似文献   

Harmonic analysis and an empirical model for TEC over Palehua     

《Journal of Atmospheric and Solar》2002,64(17):1833-1840

An empirical model of total electron content (TEC) for a low-latitude station, Palehua, has been developed using harmonic analysis of TEC data measured at this station during the period 1980–1990; the TEC data were obtained from Faraday rotation measurements of linearly polarised signals transmitted by geostationary satellites. The analysis reveals that monthly mean values of the daily mean and the first four harmonics vary in phase with solar activity and exhibit annual, semi-annual variations and equinoctial asymmetries. A set of 81 coefficients of zero and the first four orders were determined which were found to be sufficient to model the TEC. The model strongly depends on the sunspot number. The harmonic components derived from the 81 coefficients are scaled by this property. The modelled monthly mean TEC values agree quantitatively with the measured data, the maximum deviation being limited to ±15%. The model reasonably reproduces the features observed in the diurnal, seasonal and solar cycle variations of the measured data. The annual variation of observed TEC exhibits opposite equinoctial asymmetries at solar minimum and solar maximum. Also, the mean and first four harmonics show a saturation/decreasing effect when the sunspot number exceeds about 170. The observed features are discussed qualitatively.  相似文献   

良庄井田地质构造特征及其对矿井突水的影响     

邱梅  施龙青  王国瑞  高卫富  孙祺 《煤田地质与勘探》2012,40(5):51-55

根据大量地质资料揭示了山东良庄井田地质构造的发育特征,其断裂构造具有分区性、方向性、垂向分层性、成带性等特点,并推断井田内发育有滑动构造。探讨了该井田地质构造发育规律对矿井突水的影响,着重分析了滑动构造对矿井突水的作用。研究表明,断裂构造的分区性、方向性、垂向分层性、成带性及滑动构造对矿井突水有不同程度的影响。   相似文献   

我国北方典型岩溶地下水位对降水及气象指数的响应特征——以鲁中地区为例   总被引：2，自引：1，他引：1  

李传生  祁晓凡  王雨山  安永会  邢立亭 《中国岩溶》2019,38(5):643-652

我国北方岩溶水资源是其经济社会发展的重要资源基础,表征水资源赋存特征的岩溶地下水位动态及其影响因素分析能够为岩溶水资源管理及合理开发利用提供重要支撑。本文选取鲁中地区3个典型水文地质单元,基于2010-2017年月值降水、地下水位及NPI气象指数数据,采用小波分析方法对上述指标的周期性、响应特征及遥相关特征进行了分析。结果表明:（1）各岩溶地下水位动态、降水与NPI的主波动周期均为1 a,其显著周期与分布时段等的异同是受自然条件和人类活动共同作用的结果。（2）各水文地质单元岩溶水位对降水的响应时滞为95.81~146.64 d,其差异主要源于观测站所处的地下水流系统的位置的不同。（3）NPI与降水存在一定的遥相关,与受降水影响的岩溶水位动态也存在遥相关。各岩溶水位对NPI的遥相关时滞为111.75~169.77 d,相比水位对降水时滞有所增加。鲁中岩溶地区地下水位对降水与NPI存在规律性的响应时滞,此种特征可为我国北方岩溶地下水位的预警预报提供帮助。   相似文献   

基于土石坝动力特性的坝料动力参数反演     

刘振平  迟世春  任宪勇 《岩土力学》2014,35(9):2594-2601

采用现行的室内外试验方法确定的土石料动力参数与实际坝料的动力参数有何差异是人们关心的问题之一。提出了基于土石坝动力特性的坝料动力参数反演方法,并使用该方法反演了一个假想混凝土面板堆石坝的坝料动力参数,证明该方法是可行的,计算精度基本满足实际工程要求。利用紫坪铺面板堆石坝在汶川地震中的余震加速度响应信息,反演了坝料的最大动剪切模量系数K和指数n。结果表明,由室内动三轴试验得到的坝料最大动剪切模量系数K值偏小,建议进一步研究予以修正。  相似文献   

泗水南部灰岩地区矿泉水锶源及形成条件分析          下载免费PDF全文

肖为国  冯凤玲  王集宁  冯克印  付娟 《山东国土资源》2013,29(4):29-31

通过对泗水县南部灰岩地区矿泉水储水地层岩矿分析、地质构成、水文地质条件和水动力条件等因素的调查,研究了矿泉水中锶的来源及其形成条件,认为该区域地层中含锶矿物的溶解是矿泉水中锶的天然来源,该区域独特的地质构造为含锶水进入提供了通道,并构造其富集单元,为今后开展矿泉水调查、评价和开发利用工作提供了方向。  相似文献   

基于BDI决策的居住空间宜居性分析——以大连沙河口区为例   总被引：1，自引：0，他引：1  

张延伟  裴颖  葛全胜 《地理研究》2016,35(12):2227-2237

以土地利用、社会经济、高程数据为基础,应用BDI决策多智能体模型研究大连市沙河口区居住空间宜居性。结果表明：① 大连市沙河口区星海湾街道居住空间适宜性评价数值为32.186,居住空间以星海湾街道适宜性为最佳,其次是南沙街道25.288,黑石礁街道22.098。② 绿地影响着居住空间的适宜性,居民的生活离不开优美的生态环境。③ 适宜居住空间有绿化较好,公共设施完善,居住空间所在区地面平缓,交通发达且及居民点聚集不十分密集的特点。总体而言,沙河口区居住空间宜居性差异性大,东南方向居住空间适宜性较强,全区整体呈现?型分布。  相似文献   

多波束测深系统在航道淤积计算中的应用     

许传新 《世界地质》2017,36(1):311-315

潍坊森达美港航道受2015年3月18日黄渤海风暴潮影响导致航道泥沙淤积,为推算泥沙淤积的数量,根据航道的吨级、长度、淤积程度,选取距离海岸线远近不同、淤积程度不同的三段航道采用多波束测深系统进行海下地形测量,与风暴潮到来之前的航道地形数据进行比对,计算出三段航道受风暴潮影响后泥沙的淤积数量,推算整个航道受风暴潮影响淤积量,从而评估风暴潮给航道施工单位带来的损失。  相似文献   

The characteristics of gully erosion over rolling hilly black soil areas of Northeast China     

HU Gang  WU Yongqiu  LIU Baoyuan  ZHANG Yongguang  YOU Zhimin  YU Zhangtao 《地理学报》2009,19(3):309-320

In this study, short-term gully retreat was monitored from the active gullies selected in representative black soil area, using differential global positioning system (GPS). With the support of geographic information system (GIS), multi-temporal digital elevation models (DEM) were constructed from the data collected by GPS and used for further analysis. Based on the analysis of multi-temporal DEM, we discussed the erosion–deposition characteristics within gully and a developing model for black soil gully area of Northeast China was proposed. The results are: (1) The analysis of the monitored gully data in 2004 indicated that the retreat of gully head reached more than 10 m, gully area extended 170–400 m2, net gully eroded volume 220–320 m3,and gully erosion modulus 2200–4800 t?km?2?a?1. (2) Compared with the mature gully the initial gully grows rapidly, and its erosion parameters are relatively large. The erosion parameters have not only to do with flow energy, but also with the growth phase. (3) There are significant seasonal differences in gully erosion parameters. The extension of gully area and width dominates in winter and spring without marked net erosion while changes mainly occur in gully head and net erosion in rainy season. (4) It is remarkable for freeze-thaw erosion in the black soil area of NE China. The gully wall of SG2 extended 0.45 m under freeze-thaw effect in 2004, and the distance of gully head retreated maximally 6.4 m. (5) Due to freeze-thaw action and snowmelt, gully is primarily in the interior adjustment process in winter and early spring. There are much more depositions compared with that during rainy season, which can almost happen throughout the gully, while erosion mostly occurs near head, esp. for gullies having a relatively long history of development. On the other hand, the process of energy exchange with exterior dominates in rainy season. It is considered that this cyclic process is an important mechanism for gully growth in high latitude or/and high attitude regions.  相似文献   

边坡加固中预应力锚索失效机制与失效效应研究   总被引：4，自引：0，他引：4  

李英勇  张顶立  张宏博  宋修广 《岩土力学》2010,31(1):144-150

预应力锚索已广泛应用于边坡加固工程中,由于其承受高拉应力作用,并长期埋置于潮湿的岩土环境中,在综合因素的作用下存在失效的可能性。结合实体工程中的大量监测数据,对预应力锚固系统长期稳定性的影响因素进行了深入分析,提出了预应力锚固系统的失效机制;为了分析锚索失效效应,确定合理的处理时机,分别进行了现场卸载试验及数值模拟,研究了单锚及群锚失效效应,提出了边坡局部失稳的判据,其结果可为类似工程提供借鉴。  相似文献