锚杆在客土喷播技术中的受力状况分析

分析了适用于深层稳定岩石边坡的客土喷播植被护坡技术中的锚杆受力时的稳定情况,并以花岗岩岩体边坡中锚杆设计为例,计算出锚杆的最佳间距和最佳锚固深度.     

公路高边坡整治中的支架式岩体锚固施工

在高边坡锚固施工过程中,一般采用边削坡边对边坡进行锚固的方法进行施工,避免完全削坡后造成无锚固施工操作面的困难,但在二次高边坡锚固整治或高边坡坍塌整治中该方法有较大的局限性.现以缅甸瑞丽江电站进场公路K48+600～K48+800段高边坡大塌方整治工程为例子,论述了支架式岩体锚杆锚固施工方法.     

金沙江乌东德水电站导流洞进口层状结构边坡分区与失稳模式分析

以金沙江乌东德水电站导流洞进口边坡为例,提出了边坡结构与岩体质量双因素结合的层状结构边坡分区法,各区不同的主控因素对应不同失稳模式,可较为全面地把握边坡稳定性的根本。以该方法将该边坡分为Ⅳ1级顺向坡、Ⅳ1级斜向坡、Ⅳ2级横向坡三个区,Ⅳ1级顺向坡以边坡结构为失稳模式主控因素,Ⅳ2级横向坡以岩体质量为失稳模式主控因素。     

锚杆锚固质量声波检测在两河口水电站中的应用

锚杆锚固质量是否合格作为判定锚杆是否达到设计要求和被锚固的岩体是否安全的手段,其检测方法决定了被检锚杆锚固质量的准确性。文章通过介绍声波无损检测技术的工作原理及工程应用,简单说明了无损声波检测在锚杆锚固质量检测中的优越性。     

厚层基材喷附技术在半干旱山区高速公路边坡防护中的应用

对呼集高速公路工程建设过程中边坡防护绿化采用厚层基材喷附技术进行经验总结,阐述了厚层基材喷附技术的基本原理、适用条件、材料组成、技术特点、应用前景以及厚层基材喷附的施工方法、施工工艺等,对我国山区高速公路边坡防护方案提供有益的参考。     

不同降雨强度下植被护坡对边坡位移的影响

为研究不同降雨强度下植物根系对边坡土体位移的控制效果,采用PLAXIS 3D有限元软件对3种降雨强度下植物根系固土边坡进行数值模拟计算,结果表明:边坡未采用植物根系护坡时,降雨会导致边坡表层土体发生较大位移,土体位移增大范围包含整个坡面。边坡采用植物根系护坡时,能有效减少边坡表层土体位移,边坡土体位移增大范围比无根系防护边坡明显减小,主要分布在边坡坡面中上部。降雨强度为5,10和20 mm/h时,植物根系固土边坡土体最大位移相比无根系防护边坡减小幅度分别为89.8%,80.3%和71.8%,可见降雨条件下植物根系能够有效控制边坡土体位移,但随着降雨强度增大,植物根系对边坡表层土体位移的控制效果会有所减弱。对边坡进行稳定性分析可知,植物根系的存在能有效提高边坡浅层范围内土体的抗剪强度,从而使边坡表层土体塑性点数量减少;还能显著减小发生滑坡时的偏应变增量,并且缩小潜在滑动面的发生区域,提升边坡的稳定性。为了保证强降雨条件下边坡稳定性,提出了植物根系结合锚杆支护的综合护坡方式,该支护方式能够有效降低强降雨条件下边坡土体的位移,增强边坡稳定性。     

玻纤格栅抵抗不同宽度裂缝反射性能的研究

以加铺玻纤格栅提高沥青面层抗反射能力为研究背景,在室内进行静载有侧限、静载无侧限和动载三种情况,模拟不同宽度的裂缝进行抗反射裂缝试验,并为保证格栅与结构层的粘结性能进行最佳沥青用量试验,结果表明,格栅可以抵抗一定宽度内裂缝发展,但对裂缝的初裂性能上影响较小,对于裂缝在沥青加铺层中的扩展具有良好的改善作用,裂缝的发展形态与路面结构、材料和原始裂缝相关,格栅的有效能力为15%～40%,基层的侧限强度对裂缝扩展影响很大。     

宝天高速公路边坡植被防护应用

在宝天高速公路路基、路堑边坡绿化工程项目上,分别采用三维网植被防护,厚层基材喷射植被防护的形式进行防护种植.较为系统的阐述了三维网植被防护,厚层基材喷射植被防护的施工工艺与方法,为今后在同类地面开展边坡绿化提供参数依据.     

乌海市平沟煤矸石山小地形土壤养分分析

文章以乌海市平沟煤矸石山上平台和边坡两种不同小地形上的土壤为研究对象,通过野外调查取样和室内分析化验,研究煤矸石山两种小地形对土壤养分的恢复情况。结果表明,土壤有机质、全N、碱解N含量在两种不同小地形上表现为边坡>平台,土壤P素、K素含量表现为平台>边坡,总体而言,边坡上土壤养分恢复效果比平台好。平台和边坡上土壤养分含量在不同土层深度中均表现为:0~20 cm层>20~40 cm层。通过参考土壤养分分级与丰缺度标准,目前土壤养分丰缺度主要呈现出缺或极缺状态。     

利用土钉支护技术处理深基坑的护壁问题

深基坑逐层开挖,逐层在边坡以较密排列打入土钉钢筋,强化坑边坡土体的受力,并在坡面上设钢筋网,分层喷射混凝土,这就是深基坑支护中的土钉支护方法。这种方法与锚杆支护、加筋比较,具有独特的优点。     

CFRP体外预应力筋锚固装置受力性能的试验研究

锚固装置是既有桥梁结构体外预应力加固体系中的重要组成部分,安全性及可靠度要求高,具有受力性能复杂及非线性程度高等特点,理论分析难度大.为研究CFRP体外预应力筋加固梁中锚固装置的实际受力性能,掌握锚固装置的可靠程度,本文通过试验分析手段,在CFRP体外预应力筋张拉阶段及试验梁加载破坏过程中,对直线型锚固装置锚固齿板应变和高强螺栓螺杆应变进行了测试,并对应变及变形参数等试验结果进行了详尽的理论分析.试验结果表明采用的锚固装置是安全可靠的,可以满足要求.通过试验分析,掌握了锚固齿板及高强螺栓螺杆的受力特点及提高锚固装置安全性的方法,为CFRP体外预应力筋锚固装置的设计及施工提供参考.     

明洞局部应力计算浅析

坝陵河大桥是沪瑞国道主干线贵州省镇宁至胜境关高速公路主跨1088m的单跨吊悬索桥。西锚碇为隧道锚,该隧道锚为目前国内最大的隧道式锚碇。由于锚碇上端的明洞一侧有汽车荷载的作用,而另外一侧只有土压力的作用,为了验算结构的受力状况,建立三维模型,进行三维有限元分析。本次分析根据结构的空间尺寸建立计算模型,考虑明洞在最不利荷载工况组合作用下承受的最大内力,进行结构应力分析,并据此进行结构强度分析。     

谈锚杆框架梁＋浆砌片石在边坡防护中的应用

锚杆框架梁＋浆砌片石作为一种路堑高边坡防护加固技术，主要适用于高陡岩石、地质条件复杂地段边坡，特别是针对岩石极易风化、崩解、滑动的特征边坡，能有效地保证边坡的稳定性，且结构布置合理。     

客土喷播的护坡机理及基材和施工等控制要点

针对许多的岩质边坡,工程防护与周围环境极不协调;而植被护坡既缺少植物生长的土壤基础,又忽略边坡防护效果。客土喷播在一定程度上解决这一矛盾,本文对比分析客土喷播的护坡机理,详细地介绍基材及其要求,对其施工工艺等方面也做了全面阐述,对目前研究过程中存在的几个问题提出针对性的建议。期望推动客土喷播的研究不断深入和发展,促进客土喷播理论和技术上都更加成熟。     

A comparison of root distribution of three hardwood species grown on a hillside in the Caspian forest,Iran

Slope is a complex environmental factor that can subject plants to a number of mechanical stresses. The anchorage of roots and improvement of slope stability mainly depend on specific properties of root systems, such as root distribution. In the present study, 24 trees (from three species) growing on gentle slopes (10–20°) were randomly chosen for root distribution analysis. The profile trenching method was used to obtain root characteristics. The findings indicated that root area ratio (RAR) decreased with depth and that maximum RAR values were observed in the upper layers; RAR values were between 0.0004% and 6.6444%. Average RAR values were not statistically different in upslope and downslope layers except in one case. The dot grid method (100 × 150 mm) usually overestimated the RAR values. The amount of roots decreased with depth following a power law. About 50% and 90% of roots were located in the first 30 and 60 cm depths, respectively. Results of analysis of covariance (ANCOVA) showed a significant effect of diameter at breast height (DBH) on total RAR but not on the total number of roots. About 70% of roots had diameter of less than 10 mm. Spearman’s correlation showed significant negative correlation between the total number of roots and the amount of N, P, and K elements, and a positive correlation between DBH and RAR. The results serve to develop understanding of the biotechnical characteristics of root systems of Caspian species.     

锚管桩+锚索+框架梁复合支护在高边坡防护中的应用

以吉林敦化至延吉一级公路12合同段锚管桩、锚索、框架梁工程为例，介绍锚管桩＋锚索＋框架梁复合支护体系的应用情况及施工方法，进行了预应力锚索生产性试验过程与分析，以及生产性试验验证和调整设计参数。     

不同坡向杉木3代种子园土壤有效养分差异比较分析

以杉木3代种子园为研究对象,分析不同坡向杉木3代种子园土壤有效养分含量差异,从而为实现杉木种子园的合理施肥奠定理论基础。研究结果表明,同一坡向随着坡位上升以及同一坡位随着土层深度的增加,杉木3代种子园土壤有效养分含量呈逐渐下降趋势;同一坡位同一土层深度不同坡向对土壤有效养分含量的影响体现出较为复杂的规律。     

Root anchorage of hinoki <Emphasis Type="Italic">(Chamaecyparis obtuse</Emphasis> (Sieb. Et Zucc.) Endl.) under the combined loading of wind and rapidly supplied water on soil: analyses based on tree-pulling experiments

Wind damage in Japan is mainly caused by typhoons (i.e., tropical cyclones), which are characterized by intensive heavy rainfall and strong winds. In this study, we conducted tree-pulling experiments on two sites to find out whether rapidly supplied water on the soil would affect stability of root anchorage of hinoki (Chamaecyparis obtuse (Sieb. Et Zucc.) Endl.), as expected. For the experiments, we first supplied several quantities of water around the target trees, and then they were pulled down using a wire winch. On study site 1 (Kamiatago experimental forest), we applied general tree-pulling experiments (no water supply) in 2008 and six different irrigation treatments around the target trees in 2009. On study site 2 (Chiyoda experimental forest), we applied one irrigation treatment in 2009. As a result, five trees were uprooted and two were broken in 2008, and all nine trees were uprooted in 2009 on study site 1, regardless of irrigation treatment. On study site 2, two trees pulled down after 4 h of water supply were ruptured at the stem base, opposite to two trees pulled down immediately after supplying water. The water content below the root plate significantly affected root anchorage and more specifically, the maximum turning moment, stem angle at the maximum force, and stiffness index. Moreover, water inside the root plate increased root anchorage at the beginning of a tree failure process. However, it also reduced the root plate area of the hinge side. Conversely, high water content below the root plate decreased root anchorage.     

高边坡整治工程中预应力锚索应用

在水利、道路及城市建设过程中,因人工开挖往往形成人工高陡岩质边坡,如不加以支护加固处理,在降雨及其他因素作用或影响下易形成崩塌或滑坡灾害,造成人员或财产损失。以巫师附小治理工程为例,对高陡的边坡采取加固处理,加固措施采用1000 kN级预应力锚索,共42束,进尺1010 m,施工后对边坡进行了变形监测,监测数据表明:加固后的边坡满足设计要求。     

机械运输对伊朗北部山林陡峭集材道土壤的干扰

A study was conducted to investigate the effects of skid trail slope and traffic levels on soil disturbances at two soil depths (0–10 and 10–20 cm). The treatments were set at four traffic levels (2, 7, 12 and 20), two slope classes (<20% and >20%) and two soil depths (0–10 and 10–20 cm). Results show that skidder traffic, longitudinal slope and soil depth have significant effect on soil bulk density in skid trail. Comparison of average soil bulk density in different traffic levels shows that there are significant differences in average bulk density between different traffic levels and control (p<0.05). The average bulk densities in different slopes and soil depths are significantly increased with increase in traffic levels, maximized at 12 passes (p<0.05), but there are no significant differences between 12 and 20 passes. The interaction effects between traffic and soil depth are significant (F _0.05,3=0.109, p<0.001). For all traffic treatments, there are significant differences in soil moisture content between the two slope classes and the two depths (p<0.001). However, the interaction effects between traffic levels and slope classes are not significant (p >0.05), although skidder traffic and slope affected soil moisture content.