Slope Protection with Vegetation of Baoji(Shaanxi)-Hanzhong(Shaanxi) Expressway

With expressway development and environment protection consciousness improving, slope protection technology with vegetation has drawn much more attention. From the perspective of ecology, Baoji-Hanzhong Expressway maximized slope protection technology with vegetation and formed attracting landscapes on basis of eco-protection. This research introduced the technology of Baoji-Hanzhong Expressway, and explored a low-cost and effective biological slopeprotection way, suitable for Baoji-Hanzhong Expressway, according to slope protection technologies, at home and abroad, with botany, water and soil conservation engineering, and architecture, which fixed and stabilized slopes, prevented rainfall scouring, and advanced slope protection development in China.

Root structure of slope protection plants in a high-grade highway

Root length and root length density of Lespedeza bicolor,Amorpha fruticosa,and Sea buckthorn were investigated in a country highway-TongSan highway（Tongjiang to Sanya） in Heilongjiang Province,China.The root lengths were divided into five root orders according to Pregizter sequence classification method.Results show that sea buckthorn roots are dominated by coarse roots in the horizontal growth,while L.bicolor has a large proportion of fine roots in vertical conical growth and A.fruticosa is in depth growth.Root length density of L.bicolor in all the root sequences is higher than that of sea buckthorn and A.fruticosa.On the basis of the root structure,it is inferred that L.bicolor roots mainly absorb the surface soil moisture for its normal growth;in contrast,A.fruticosa has good uptake ability to deep soil water.The root structure of sea buckthorn implies that it has a strong drought resistance.

Study on Mechanism and Control Effect of Highway Slope Ecological Protection

At present,with the rapid development of social economy,people's awareness of environmental protection continues to increase,and environmental construction and environmental protection work are put on the agenda.Highway slope greening protection is an important means to achieve social sustainable development.Developed countries carried out research earlier in this area,and China's research in this area started later.In engineering construction,ecological protection is to realize slope reinforcement and slope protection depending on the water storage and soil fixation effects of vegetation.Its slope protection can be summarized as the mechanical effect of root system and the hydrological effect of vegetation.As a basic form of slope greening protection,it is necessary for us to understand the mechanism of ecological protection and to enhance the design of ecological protection accordingly.Based on this,the article analyzed the development of slope greening protection technology and ecological protection mechanism from different angles,so as to establish a theoretical framework for future research.

Study on the Bioengineering Protection Technique for Rock Slopes in Railway

Ecological protection technique of rock slope is a new slope protection technique,and it is used widely in some supporting engineering of rock slope at railway and highway.But it is always an important research in the field of geotechnical engineering, because the study is related to many subjects and is not systemic and idiographic enough.The paper takes the rock slope of Luozhan(from Luoyang to Zhanjiang)

Stability evaluation and protection of slope for Laosongling-Yanji Highway

The authors analyzed the engineering geological characteristics of the slope of the study area (K75+840-K76+340). Two typical cross-sections have been chosen to analyze the failure modes after the excavation of the highway. Different types of the failure modes have been calculated and analyzed. The results show that some dealing methods have been advised to ensure the stability of the slopes.

Large-scale model testing of high-pressure grouting reinforcement for bedding slope with rapid-setting polyurethane

Bedding slope is a typical heterogeneous slope consisting of different soil/rock layers and is likely to slide along the weakest interface.Conventional slope protection methods for bedding slopes,such as retaining walls,stabilizing piles,and anchors,are time-consuming and labor-and energy-intensive.This study proposes an innovative polymer grout method to improve the bearing capacity and reduce the displacement of bedding slopes.A series of large-scale model tests were carried out to verify the effectiveness of polymer grout in protecting bedding slopes.Specifically,load-displacement relationships and failure patterns were analyzed for different testing slopes with various dosages of polymer.Results show the great potential of polymer grout in improving bearing capacity,reducing settlement,and protecting slopes from being crushed under shearing.The polymer-treated slopes remained structurally intact,while the untreated slope exhibited considerable damage when subjected to loads surpassing the bearing capacity.It is also found that polymer-cemented soils concentrate around the injection pipe,forming a fan-shaped sheet-like structure.This study proves the improvement of polymer grouting for bedding slope treatment and will contribute to the development of a fast method to protect bedding slopes from landslides.

Thermal features of Qinghai-Tibet Railway Embankment with Crushed-stone Slope Protection in Permafrost Regions

The Embankment with Crushed-Stone Slope Protection(ECSSP) in permafrost regions is an effective measure to cool subgrade and protect permafrost.It can mitigate the engineering hazards of the Qinghai-Tibet railway in the permafrost regions. Considering the influence of the noctumal cold air during summer months in Qinghai-Tibet Plateau。

黄土边坡微生物矿化加固及植被恢复试验

[目的]研究黄土边坡微生物矿化加固及植被恢复,为黄土边坡的加固及坡面土壤侵蚀防治提供新方法和新技术。[方法]采用微生物诱导碳酸钙沉淀(Microbially Induced Calcite Precipitation,MICP)技术对黄土边坡进行矿化加固处理,并在固化黄土边坡上进行植被恢复,利用扫描电子显微镜(SEM)和光学显微镜,从微观角度探究MICP技术对黄土边坡矿化加固的作用机制,并统计分析了固化黄土边坡的植被恢复效果。[结果]采用MICP技术对黄土边坡进行固化处理后,在坡面上生成的固化层将松散且相邻的土壤颗粒胶结在一起,使黄土坡面形成一个整体,固化层最大厚度为0.23 cm,平均厚度为0.21 cm;固化黄土边坡恢复植被后第60天,A1,A2,B1,B2,A1B1,A2B2各区域内植被成活率比A0,B0,A0B0各区域分别显著提高26.66%,20%,37.5%,25%,33.33%,25%(p<0.05),第60天后,各区域内植被的成活率均差异显著,而且固化后加保水剂的A1,B1,A1B1各区域内植被的成活率最高;固化后加保水剂的B1和A1B1区域内紫穗槐高度和地径的生长变化量最大,且固化后加保水剂的A1,B1,A1B1各区域内麦冬草和紫穗槐的生长状况最好。[结论]采用MIC技术可以有效固化黄土坡面,与植被恢复技术相结合,既能防治土壤侵蚀,又能恢复生态环境。这种综合防治措施为黄土边坡水土流失防治与生态修复提供了良好的技术支持。

生态治理模式对公路边坡植物多样性与土壤特性的影响

为探讨公路边坡不同生态治理模式的植被恢复效果,以福建福州已建设完成1.5、8.0 a的2条公路的3种不同生态治理模式边坡[液压喷播植草护坡(Ⅰ)、锚索框架地梁内植草护坡(Ⅱ)、人字形骨架植草护坡(Ⅲ)]为研究对象,比较不同生态治理模式下的植物多样性与土壤特性,分析公路边坡植物多样性与土壤特性之间的关系。结果表明:(1)不同生态治理模式的边坡植被群落主要由豆科、菊科和禾本科植物组成。不同恢复时间下,Shannon-Wiener指数、Simpson指数、Pielou指数均表现为生态治理模式Ⅱ>Ⅲ>Ⅰ,而Margalef指数则表现为生态治理模式Ⅲ>Ⅱ>Ⅰ。3种不同生态治理模式公路边坡的植被覆盖度均为恢复8.0 a大于恢复1.5 a。(2)恢复1.5 a的3种生态治理模式公路边坡的土壤理化性质之间差异较小且不显著,而恢复8.0 a的土壤理化性质之间差异较大,尤其土壤pH值、有机质和速效钾含量呈显著差异(P<0.05)。生态治理模式Ⅲ的土壤团聚体水稳性、土壤抗冲性最佳。3种生态治理模式下,公路边坡土壤团聚体水稳性及土壤抗冲性均表现为恢复1.5 a大于恢复8.0 a。(3)Margalef指数、Shannon-Wiener指数、Simpson指数、Pielou指数、植被覆盖度均与全钾含量呈极显著正相关(P<0.01);除Pielou指数外,其余3个植物多样性指数均与土壤全氮、全磷含量呈显著负相关(P<0.05),与土壤抗冲指数呈显著正相关(P<0.05);边坡坡长与植物多样性指数呈显著负相关(P<0.05),坡度与土壤抗冲性、土壤团聚体水稳性呈显著负相关(P<0.05)。综合比较,生态治理模式Ⅲ为公路边坡生态治理效果较佳的模式。

寒区土质边坡蜂格网护坡技术应用

蜂格网作为一种新型的护坡材料,由于其独特的结构和优良的性能从而在边坡防护工程中备受关注。以铁科高速公路建设工程延寿段为依托,提出“蜂格网填充原边坡土+紫穗槐”的土质边坡加固方案。在实际应用中,利用蜂格网防护系统对土体进行锚固,能够减少因雨水冲刷而导致的土体流失现象,通过这种方式,极大地增强了边坡的稳定性,有效降低了滑塌发生的机率。此方案将主要聚焦于蜂格网防护系统在土质边坡防护中的技术研究,其中涵盖了施工材料的选择、施工工艺等多个重要方面。

植被护坡对河岸坡体稳定性影响及机理研究

香根草是一种极好的护坡植物,其平均抗拉强度为75 MPa(即约为软钢强度的1/6),被称为边坡表层的“活土钉”。因此研究香根草的护坡效果具有重要工程意义。文章以广东某河岸边坡治理工程为例,采用有限元程序PLAXIS和强度折减法,探讨了香根草的间距、种植角度和根系深度对边坡稳定性的影响,探讨了其加固机理。研究结果表明,由于植物根系间的锚固作用,能够增强植物根系与土壤间的凝聚力,能够较好地提高边坡稳定性,值得推广应用。

高速公路路基高边坡稳定性及加固方案

针对太原西北二环高速公路K18+620右侧高边坡出现的滑移现象及地质不稳定问题,通过现场勘查和地质调查,分析了高边坡岩体结构特征和边坡变形的主要诱发因素,利用简化Bishop法,进行了边坡稳定性计算和评估,计算结果表明,在天然、地震及有水工况下,边坡均存在不同程度的滑移风险,采用“锚杆+坡面格构”相结合的防护设计方案,结合排水系统设置和植被修复等综合防护措施,以提高边坡的抗滑能力及稳定性。

公路路基边坡锚杆格梁防护技术研究

文章以山东省某公路工程为例,通过边坡节理赤平投影分析了边坡稳定性,计算了三种工况下的边坡稳定性系数,并确定了锚杆格梁护坡的技术参数,最后应用有限元软件计算了增设锚杆格梁前后边坡的位移和剪应力分布。研究结果表明:边坡节理投影交点处于边坡投影弧的另外一侧,且位于软弱结构面的坡体内部,边坡部分岩体在极端气候或地震作用下会处于欠稳定状态;增设锚杆格梁护坡后,边坡受力得到较大改善,边坡下部位移和剪应力集中明显变小,边坡稳定性提高。

路基防护工程施工技术在公路工程中的应用

结合广连高速公路高边坡防护工程,从测量放线、地基开挖、钢筋制作、模板安装、混凝土浇筑等几个方面,对基坑高边坡锚杆框架梁的防护设计、施工前的准备工作、施工中应注意的问题和施工注意事项进行研究。结果显示:挖方高边坡的防护设计满足边坡的安全、稳定性能,保障了项目的整体质量,在社会效益、经济效益上取得了一定的成就。

台阶布置在变电站竖向设计中的应用

变电站竖向设计需根据地形特点,因地制宜采取不同设计方案。文章对厄瓜多尔某500kV变电站工程采取台阶式布置,将变电站站区划分为5级台地,取得显著的经济效益。对台阶布置需重点关注的工艺布置、交通组织、场地排水、边坡支护等设计要点进行总结分析,供类似工程参考。

河道防洪治理的工程措施探析

针对诸多河道治理工程措施尚无系统比较分析,易造成经费浪费或治理效果不达标的情况发生,本文简要介绍了河道防洪治理各工程措施的特点,并以徒骇河防洪治理工程为例,详细介绍了一种“防洪墙护岸+河道清理+排水涵闸”的综合治理措施,其思路和经验可供类似工程治理项目参考借鉴。

隧道洞门区水土流失机理分析与水土保持技术

本文以某隧道工程为例,探究了隧道洞门区的水土流失机理,并提出了水土保持措施。结合现场调查情况,分析认为隧道洞门区水土流失主要与水力侵蚀和重力侵蚀有关。在此基础上基于永临结合、重点治理与全局治理结合原则提出了水土保持方案。该方案共包含三部分,工程措施方面采取了设置坡顶截水沟、表土剥离和覆土整理措施;植物措施方面采取了客土喷播植草技术;临时措施方面设置了临时排水沟、临时沉砂池和临时挡土墙。通过综合采取水土保持技术,切实提高了隧道洞门区的蓄水保土能力。

Mechanical analysis of interaction between plant roots and rock and soil mass in slope vegetation

With the help of plant roots, slope vegetation makes the slope soil mass become a composite material of soil and roots, and thus enhances shear strength of the slope soil mass and stability of the slope. However, the related studies at present are still qualitative. In this paper, quantitative analysis of the interaction between roots and soil mass are made. By the analysis of the interaction between herbaceous plant roots including lateral roots of woody plants and rock and soil mass, a mechanical model of the interaction between frictional roots and soil is established, and its correctness is shown. A mechanical model of the interaction between anchorage root, namely, woody plant taproot, and soil is also established. The establishment of the models provides a useful means in quantitative analysis of the interaction between plant roots and soil, and has practical values.

DESIGN SLOPE牺牲阳极阴极保护设计方法

海洋工程领域常用的牺牲阳极阴极保护设计法可能存在过度设计的问题。针对此问题,文章介绍了适用于无涂层结构物的DESIGN SLOPE牺牲阳极阴极保护设计法。首先,简述了阴极保护下结构物表面生成钙镁沉积层的机理,分析了结构物表面极化特性在设计寿命期内的变化情况;然后,结合牺牲阳极阴极保护系统等效电路,引出DESIGN SLOPE的概念,说明该设计方法的基本理论;最后,应用DESIGN SLOPE设计法完成某平台牺牲阳极阴极保护设计工作。该法能够避免牺牲阳极阴极保护过度设计,从而提高设计方案的经济性。

高速公路边坡生态防护技术及发展趋势分析

该文详细阐述生态防护在高速公路工程建设中的重要性,主要通过植被的蓄水、保肥和固土功能来加固和保护边坡。这种防护作用主要体现在根系的力学效应和植被的水文效应2个方面。同时,深入探讨公路路基边坡生态防护技术及其机理,并试图将这些知识应用于提升生态防护技术手段。为实现此目标,结合多年野外工作实践经验,以公路边坡植物防护技术为研究对象,从多角度对边坡植树种草防护技术的发展和生态防护机理进行深入分析。