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1.
植被护坡及其在重庆地区的应用 总被引：3，自引：0，他引：3
边坡工程中的植被不仅能美化环境，还具有控制雨水冲蚀、稳定边坡的作用。文章详细论述了植被护坡的边坡滑移面上的边坡稳定系数的评定方法，并与无植被边坡稳定性进行比较，讨论了植被护坡的力学效应和水文作用、植被对雨水冲蚀的控制作用，提出了植被护坡的种植和布置方法的建议。结合重庆地区的边坡特点和气候条件，介绍和分析了该地区的几项典型植被护坡工程及施工方法和施工效果，为植被护坡技术的推广和应用提供借鉴和参考。 相似文献
2.
月河是汉江左岸较大的一级支流,安康汉滨区处月河下游段,径流量大,防洪压力大,故在城区沿河段采用了多种护坡形式,选择合理护坡形式是保障河段行洪安全的重要措施。通过对汉滨区城区堤防工程建设中多种护坡形式进行比选分析,总结各种护坡的优缺点,最终优先适宜护坡形式。比选结果可知：在防洪工程建设中共采用浆砌石挡墙、浆砌石护坡、干砌石护坡三种传统护坡和新型的生态砼护坡和铰接式护坡;从一个汛期检验效果看,生态砼护坡生态效果最佳,铰接式护坡次之。浆砌石挡墙节约土地效果最佳,干砌石护坡造价最经济。分析结论为远期河道治理提供借鉴和参考。 相似文献
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4.
河道护坡在农村河道护理中发挥重要作用,生态护坡的应用不仅改善了农村河道护坡治理,同时对河道周边植被起到重要保护作用,是河道护坡模式的具体应用。本文将传统护坡模式与生态护坡模式进行对比分析,并结合相关文献资料的研究,提出传统护坡模式对生态环境的影响,同时给出生态护坡模式下的护坡功效和生态保护作用。在社会经济迅速发展的背景下,生态护坡会逐渐普及到农村河道护坡治理当中,为生态环境的可持续发展提供重要依据。 相似文献
5.
散粒体斜坡多发育于我国西部山区,由块度不一、黏粒含量较少的碎砾石土组成,由于胶结性差,遇雨水冲刷、风吹或人畜踩踏易失稳。传统坡面防护技术包括拦挡锚固和土工材料与植被构筑,新型护坡技术是结合了岩土材料加固和生态环境两方面所提出的新方法。本文中该新技术是指将浓度1.3%的改性钠羧甲基纤维素与边坡表层土拌合,后掺入植物纤维,喷洒到坡表形成加固层;加固层表面喷洒草籽,以达到边坡防护的目的。文章选择传统的护坡方法（格构和三维网）和新型土壤改良方法结合植草绿化技术对室外某散粒体斜坡进行加固处理,以天然斜坡为参照,统计降雨冲刷和径流冲刷后边坡表面侵蚀破坏、入渗和植被破坏特征,对比不同护坡方式的应用效果。试验结果表明:每个斜坡辅之相同的植草条件下,对比降雨和放水冲刷试验后各边坡的侵蚀破坏特征可以发现,材料改良植草边坡侵蚀弱,产沙量小,作用层能减缓雨水下渗,提高植被存活率和降低植被倒伏率,其效果优于三维网植草护坡和格构植草护坡。 相似文献
6.
由北京市地质工程设计研究院承担的《北京市怀柔区崎峰茶金矿区环境治理》项目于今日顺利通过专家验收。技术人员结合当地地质条件,缜密研究,大胆采用了生物植被袋新型护坡工艺,经实践,效果良好。专家组对生物植被袋护坡工艺给予高度评价,一致认为应在今后矿山环境治理中大力推广使用该工艺。 相似文献
7.
三维土工网垫植草护坡防坡面径流冲刷的机制分析 总被引：2，自引：0，他引：2
基于水力学和河流动力学的基本原理,利用坡面糙率和拦污栅模型分别模拟三维土工网垫和坡面植被作用,建立了三维土工网垫和坡面植被引起的坡面沿程水头损失和径流局部水头损失计算式,并建立三维土工网垫植草护坡时坡面径流速度计算表达式,将颗粒启动速度引入分析坡面土颗粒流失初始的启动流速,进而通过坡脚流速和坡面土颗粒启动流速的对比分析和通过分析坡角、植株密度、网垫和植被类型对坡脚流速的影响来研究三维土工网垫植草护坡的防径流冲刷特性。结果表明,坡脚流速随坡角增大而增大;网垫类型对坡脚流速影响不明显,但同无护坡时相比网垫能显著降低坡脚流速;坡脚流速随植株和叶部倾角增加而变小,且随植株密度增大而减少,并在考虑不同边坡土质的颗粒启动速度与坡脚流速相等时计算得到护坡所需的植株最小密度。 相似文献
8.
本文介绍了国内外城市垃圾的处置方法,阐明了垃圾埋场对地质环境的影响以及对垃圾堆埋场场址的选择要求。 相似文献
9.
对植被蒸腾作用以及阻滞地表径流作用进行了研究,提出生态护坡对边坡岩土体基质吸力的影响主要有3个方面：(1) 植被的蒸腾作用消耗边坡岩土体中的水分,使边坡体基质吸力升高,对边坡稳定有利;(2) 植被阻滞地表径流,增加降雨入渗量,使边坡体含水率增高,基质吸力降低,对边坡稳定不利;(3) 植被的存在究竟使边坡体基质吸力如何变化以及对边坡稳定是否有利,最终决定于降雨量和雨型。在此基础上,更进一步提出在降雨丰沛、暴雨较多的地区进行生态护坡时,应对边坡体采取防排水处理措施。 相似文献
10.
遮阳板碎石复合护坡是一种集碎石护坡和遮阳板护坡双重效用于一体的新型复合护坡结构,是一种很好的治理高温冻土区块碎石护坡路基病害的补强措施。基于遮阳板和块碎石单个工程措施降温机制的研究,通过对这种新型复合护坡路基的温度场和速度场特征以及降温过程的研究,提出新型复合护坡路基的降温机制。研究发现,封闭新型复合护坡的主要降温机制是：复合护坡中遮阳板有遮阳和挡风雪作用,碎石层有“热半导体”效应和“热屏蔽效应”（屏蔽遮阳板的二次辐射）;开放新型复合护坡的主要降温机制是：遮阳板有遮阳、挡风雪作用,碎石护坡有 “热屏蔽效应”（屏蔽热风和二次辐射）和“烟囱效应”,遮阳板和碎石护坡组合的通道有“虹吸效应”、“狭管效应”和 “烟囱效应”。研究成果完善和深化了新型复合护坡路基研究基础,而且对遮阳板和块碎石结构在青藏铁路或青藏公路中的应用提供科学依据和技术支撑。 相似文献
11.
The aim of the present study is to prepare a landslide susceptibility map of a region of about 120 km2, between Gökcesu and Pazarköy (around Mengen, NW Turkey) at approximately 10 km north of the North Anatolian Fault Zone, where frequent landslides occur. For this purpose, mechanisms of the landslides were studied by two-dimensional stability analyses together with field observations, and the parameters controlling the development of such slides were identified. Field observations indicated that the failures generally developed within the unconsolidated and/or semiconsolidated soil units in forms of rotational, successive shallow landslides within the weathered zone in Mengen, Cukurca and Sazlar formations. Although consisting of residual soils, Capak and Gökdag formations do not exhibit landslides as the natural slopes formed on these, do not exceed the critical slope angles. Statistical evaluations and distribution of the landslides on the topographical map showed that such parameters as cohesion, angle of internal friction, slope, relative height, orientation of slopes, proximity to drainage pattern, vegetation cover and proximity to major faults were the common features on the landslides. Digital images were obtained to represent all these parameters on gray scale on the SPOT image and on the digital elevation model (DEM) of the area using image processing techniques. Soil mechanics tests were carried out on 36 representative samples collected from different units, and parameters were determined for two-dimensional stability analyses basing on “sensitivity approach” and for the preparation of digital shear strength map. In order to determine the critical slope angle values for the residual soils, a series of sensitivity analyses were realized by using two-dimensional deterministic slope stability analyses techniques for varying values of cohesion, angle of internal friction and slope height along with varying saturation conditions. According to the results of the sensitivity analyses, the Mengen formation was found to be most susceptible unit to landslides, covering about 33.5% of the region studied in terms of surface area. The distribution of the critical slopes were determined by superimposing the critical slope values from sensitivity analyses on slope map of the study area. On the other hand, iso-cohesion and iso-friction maps were produced by locating the values of cohesion and internal friction angles in a geographic coordinate system such that they coincide with sample locations on the DEM and by further interpolation of the values concerned. The pixel values were evaluated in gray scale from 0 to 255, 0 representing the lowest pixel value and 255 representing the highest. Sensitivity analyses on cohesion and angle of internal friction to investigate the effects of these parameters only on stability, revealed that cohesion was effective at a rate of 70% by itself, while angle of internal friction alone controlled the stability by a rate of 30%. The iso-cohesion and iso-friction maps previously obtained were digitally combined in these rates and a “shear strength map” was prepared. The geographic setting of the study area is such that northern slopes usually receive dense precipitation. In relation to this fact, about 42% of the landslides are due north. Thus, a slope orientation map was prepared using the DEM, and slopes facing north were evaluated as being more susceptible to sliding. Proximity to the drainage pattern was another important factor in the evaluation, as streams could adversely affect the stability by either eroding the toe or saturating the slope, or both. When considered together, in conjunction with the field observations, faults and landslides showed a close association. In the area, about 88% of the landslides were detected within an area closer than 250 m to major faults, therefore, a main discontinuity map was produced using the SPOT image of the region, and “proximity to major faults” was evaluated as a parameter as most of the landslides developed in areas where the vegetation was rather sparse. A vegetation cover map was therefore obtained from the SPOT image, and the areas with denser vegetation were considered to be less susceptible to sliding with respect to the areas with less or no vegetation. Having prepared the maps accounting for the distribution of critical slopes, shear strength properties, relative height, slope angle, orientation of the slopes, vegetation cover, proximity to the drainage pattern, geographic corrections were carried on each of these, and a potential failure map was obtained for the residual soils by superimposing all these maps. Next, a classification was performed on the final map and five relative zones of susceptibility were defined. When compared with this map, all of the landslides identified in the field were found to be located in the most susceptible zone. The performance of the method used in processing the images appears to be quite high, the zones determined on the map being the zones of relative susceptibility. 相似文献
12.
植物固土护坡效应的研究现状及发展趋势 总被引：7，自引：0，他引：7
近年来由于自然环境变化和人类工程实践活动的影响,水土流失、滑坡等地质灾害发生的概率逐年提高,这些灾害的发生为当地人们的生产、生活带来了一定程度的危害。利用植物固土护坡方法可有效防治上述地质灾害的发生。植物固土护坡效应主要表现在水文效应和力学效应两方面。水文效应包括植物茎叶的降雨截留作用,植物茎叶削弱雨滴溅蚀作用,植物茎叶及其腐殖质抑制地表径流作用; 力学效应包括须状根系的加筋作用、主直根系的锚固作用和水平根系的牵拉作用等。本文着重探讨了植物护坡表现在水文效应和力学效应两方面的研究现状及其发展趋势。其中,在水文效应方面,对植物茎叶降雨截留及削弱溅蚀等进行了着重探讨; 对于力学效应着重探讨了根系增强土体抗剪强度理论模型、根-土相互作用、植物固土护坡力学效应数值模拟等。在上述基础上,指出了植物固土护坡效应发展趋势,即体现在水文效应方面,需开展大气-土体-植物水分迁移对边坡稳定性影响研究; 根-土复合体强度理论模型方面,进一步探讨Wu-Waldron-Model模型和Fiber-Bundle-Model模型所适用的工况条件; 数值模拟方面,需进一步探讨在建立计算模型时应系统考虑植物根型特征、根系强度等诸因素以及这些因素对计算结果的影响; 在工程实践方面,进一步开展植物护坡方法在边坡工程中的应用,探索植物护坡在不同地质、气候和区域环境条件下的应用与维护,使植物固土护坡效应体现出水文效应、力学效应、景观效应的有机结合。 相似文献
13.
《Physics and Chemistry of the Earth, Part A: Solid Earth and Geodesy》1999,24(10):925-934
Detailed geomorphological mapping carried out in 5 sample areas in the North of Lisbon Region allowed us to collect a set of geological and geomorphological data and to correlate them with the spatial occurrence of landslide. A total of 597 slope movements were identified in a total area of 61.7 km2, which represents about 10 landslides per km2.The main landslide conditioning factors are: lithology and geological structure, slope angle and slope morphology, land use, presence of old landslides, and human activity.The highest landslide density occurs in Cretaceous marls and marly limestones, but the largest movements are in Jurassic clays, marls and limestones.The landslide density is higher on slopes with gradients above 20 °, but the largest unstable area is found on slopes of 10 ° to 15 °, thus reflecting the presence of the biggest slope movements. There is a correlation between landslides and topographical concavities, a fact that can be interpreted as reflecting the significance of the hydrological regime in slope instability.Concerning land use, the highest density of landslides is found on slopes covered with shrub and undergrowth vegetation.About 26% of the total number of landslides are reactivation events. The presence of old landslides is particularly important in the occurrence of translational slides and complex and composite slope movements.20% of the landslide events were conditioned by anthropomorphic activity. Human's intervention manifests itself in ill-consolidated fills, cuts in potentially unstable slopes and, in a few cases, in the changing of river channels.Most slope movements in the study area exhibit a clear climatic signal. The analysis of rainfall distribution in periods of recognised slope instability allows the distinction of three situations: 1) moderate intensity rainfall episodes, responsible for minor slope movements on the bank of rivers and shallow translational slides, particularly in artificial trenches; 2) high intensity rainfall episodes, originating flash floods and most landslides triggered by bank erosion; 3) long-lasting rainfall periods, responsible for the rise of the groundwater table and triggering of landslides with deeper slip surfaces. 相似文献
14.
赣南地区滑坡灾害点多、面广、规模小,具有群发性和突发性的特点,90%以上的滑坡是因人工切坡导致的。为研究赣南地区小型削方滑坡对易发性评价模型的适用性,以赣州市于都县银坑镇为例,基于野外地质调查成果,并利用地理探测器,选取坡度、坡体结构、岩组、断层、道路、植被等6个评价指标,分别选用信息量模型、人工神经网络模型、决策树模型和逻辑回归模型开展易发性评价。结果表明：信息量、人工神经网络、决策树和逻辑回归等模型得到的AUC值分别为0.800、0.708、0.672和0.586,信息量模型所得的易发性结果与研究区滑坡实际分布情况较吻合,高易发区和中易发区滑坡占比近80%。信息量模型较其他三个模型,更适合于赣南地区小型削方滑坡易发性评价,评价结果对该地区地质灾害易发性评价模型选取提供了参考与借鉴。 相似文献
15.
A catastrophic earthquake with a Richter magnitude of 7.3 occurred in the Chi-Chi area of Nantou County on 21 September 1999.
Large-scale landslides were generated in the Chiufenershan area of Nantou County in central Taiwan. This study used a neural
network-based classifier and the proposed NDVI-based quantitative index coupled with multitemporal SPOT images and digital
elevation models (DEMs) for the assessment of long-term landscape changes and vegetation recovery conditions at the sites
of these landslides. The analyzed results indicate that high accuracy of landslide mapping can be extracted using a neural
network-based classifier, and the areas affected by these landslides have gradually been restored from 211.52 ha on 27 September
1999 to 113.71 ha on 11 March 2006, a reduction of 46.24%, after six and a half years of assessment. In accordance with topographic
analysis at the sites of the landslides, the collapsed and deposited areas of the landslide were 100.54 and 110.98 ha, with
corresponding debris volumes of 31,983,800 and 39,339,500 m3. Under natural vegetation succession, average vegetation recovery rate at the sites of the landslides reached 36.68% on 11
March 2006. The vegetation recovery conditions at the collapsed area (29.17%) are shown to be worse than at the deposited
area (57.13%) due to topsoil removal and the steep slope, which can be verified based on the field survey. From 1999 to 2006,
even though the landslide areas frequently suffered from the interference of typhoon strikes, the vegetation succession process
at the sites of the landslides was still ongoing, which indicates that nature, itself, has the capability for strong vegetation
recovery for the denudation sites. The analyzed results provide very useful information for decision-making and policy-planning
in the landslide area. 相似文献
16.
2010年4月14日07时49分(北京时间),青海省玉树县发生了Ms7.1级大地震。作者基于高分辨率遥感影像解译与现场调查验证的方法,圈定了2036处本次地震诱发滑坡。这些滑坡受地震地表破裂控制强烈,规模相对较小,常常密集成片分布。滑坡类型多样,以崩塌型滑坡为主,还包括滑动型、流滑型、碎屑流型、复合型等类型的滑坡。本文基于地理信息系统(GIS)与遥感(RS)技术,应用逻辑回归模型开展玉树地震滑坡危险性评价,并对结果合理性进行检验。应用GIS技术建立玉树地震滑坡灾害及相关滑坡影响因子空间数据库,选择高程、斜坡坡度、斜坡坡向、斜坡曲率、与水系距离、坡位、断裂、地层岩性、归一化植被指数(NDVI)、公路、同震地表破裂、地震动峰值加速度(PGA)共12个因子作为玉树地震滑坡影响因子,在GIS平台下将这些因子专题图层栅格化。应用逻辑回归模型得到每个因子分级的回归系数,然后建立滑坡危险性指数分布图。利用玉树地震滑坡空间分布图对滑坡危险性指数图进行检验,正确率达到83.21%。滑坡危险性分级结果表明,在占研究区总面积4.97%的"很高危险度"的较小范围内,实际发育滑坡数量为766个,占总滑坡面积的比例高达37.62%,表明地震滑坡危险性评价结果良好。不同危险性级别的滑坡点密度统计结果表明,滑坡点密度随着危险性级别的升高而非常迅速的升高。 相似文献
17.
植被在世界各地被广泛用于防止滑坡,但在我国东南沿海的台风季节,植被覆盖较好的地区受台风暴雨诱发常有大量滑坡发生。为了研究台风暴雨条件下植被对滑坡发育的促进作用,通过风洞物理模拟实验研究了风荷载和植被摇曳对滑坡稳定性的影响。结果表明: 台风通过植被对边坡施加的荷载不容忽视,在超强台风条件下(风速≥17 m/s),风荷载可使潜在滑坡体的下滑力增加10%以上; 由于台风的风荷载,植被会通过根部对土壤施加强大的扭矩,导致土壤出现裂缝,这些裂缝为雨水渗透提供了快速通道,土壤的渗透系数会增加10倍以上。因此在东南沿海地区的台风季节,应注意植被、特别是高大乔木对滑坡稳定性的不利影响。 相似文献
18.
Assessment of landslide susceptibility on the natural terrain of Lantau Island, Hong Kong 总被引：33，自引：1，他引：33
Steep terrain and the high frequency of tropical rainstorms make landslide occurrence on natural terrain a common phenomenon
in Hong Kong. For example, more than 800 slope failures were triggered by a rainstorm in November 1993 on Lantau Island, Hong
Kong. Maps of recent landslides interpreted from aerial photographs, in combination with a geographical information system,
were used to evaluate the frequency and distribution of landslides, with particular reference to such physical parameters
as lithology, slope gradient, slope aspect, elevation, vegetation cover, and proximity to drainage line, all of which are
considered to be influential in the occurrence of landslides. A stepwise logistic regression model was obtained between landslide
susceptibility and the above mentioned physical parameters. The study area has been classified into five classes of relative
landslide susceptibility, namely, very low, low, moderate, high, and very high, based on this methodology.
Received: 17 December 1999 · Accepted: 21 March 2000 相似文献
19.
边坡治理中的植物固坡法 总被引：11，自引：2，他引：11
植物固坡法是近年来国际上越来越流行的一种边坡治理方法。本文阐述了植物固坡法的基本原理和作用机理，介绍了当前国内外植物固坡工程的一般施工流程，对镇江市的边坡治理提出了建议，最后对植物固坡法的应用前景作了分析。 相似文献
20.
INTRODUCTIONLandslides annually cause a great amount of cas-ualties withinthe Chinese population and great lossesin the Chinese economy . The number of casualtiesreached 232 killed and 2 missing people in 2003 and283 killed and 69 missing people in 2004 . The eco-nomic losses amount to a total of 730 billion US $in2003 and 475 billion US $in 2004 (Zanetti ,2005 ,2004) .The DAAD (German Academic Exchange Serv-ice) is financing a project to investigate landslides .The project is a coo… 相似文献