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1.
《岩石力学与工程学报》2006,25(6):1225-1225
No.论文题目作者名页码1边坡柔性加固系统设计计算原理与方法阳友奎217–2252峡谷地区水电工程高边坡的稳定性研究宋胜武巩满福雷承第226–1343 SNS主动防护条件下边坡绿化及稳定性探讨罗阳明雷承弟周德培等235–2404考虑σ2作用的加筋土挡墙筋材设计计算陈秋南张永兴刘新荣等241–2455柔性防护条件下露天矿山边坡稳定性模拟分析李文秀郭玉贵戴兰芳246–2496红层泥岩边坡生态防护机制研究张俊云周德培250–2567秸秆纤维、聚丙烯酰胺及高吸水树脂在岩石边坡植被护坡中的效应李绍才孙海龙杨志荣等257–2678公路隧道洞口滑坡的机制分析及监控…  相似文献   

2.
通过试验定量研究了岩石边坡植被护坡喷射施工过程中,喷射压力、供水量及所用土壤质地对植被萌发生长及基质混合物稳定性的影响。研究结果表明:(1)植被出苗率、后期生长高度及最大收缩率随喷射压力的增加而降低,随供水量的增加而提高;(2)基质混合物抗剪强度与回弹率表现为随喷射压力的增加而提高,随供水量的增加而降低;(3)喷射压力、供水量及土壤质地对基质混合物的侵蚀影响不显著。试验条件下,各处理类型的基质混合物的产砂量变幅均为超过5%;在相同的工艺控制条件下,基质混合物所用土壤质地不同,植被出苗率、后期生长高度及基质混合物最大收缩率、抗剪强度、回弹率均有较大差异,且受工艺控制条件改变的影响程度不同。以植被出苗率、后期生长高度及基质混合物的最大收缩率、抗剪强度、回弹率为综合评价指标,对试验结果进行逐步回归分析,建立了喷射施工的效应模型,该模型中包括了喷射压力、供水量及基质混合物所用土壤的质地指标。以上研究可为岩石边坡植被护坡工程的喷射施工提供理论依据。  相似文献   

3.
研究了聚丙烯纤维、钢纤维、聚乙烯醇纤维对高性能混凝土的力学性能、抗冻性和疲劳耐久性的影响,并通过SEM进行了微观分析。结果表明,纤维掺量越高,高性能混凝土的工作性越差;掺加适量纤维能够提高高性能混凝土的抗压强度和弯拉强度,显著改善其抗盐冻侵蚀性能和抗疲劳耐久性能。聚丙烯纤维、钢纤维、聚乙烯醇纤维对高性能混凝土力学强度、抗冻性能和疲劳性能的影响存在界面增强效应、加筋阻裂效应的双重作用,从而有效延缓微裂纹的扩展和阻滞宏观裂缝的发生。适宜的聚丙烯纤维、钢纤维、聚乙烯醇纤维掺量应分别控制在0.6~0.9 kg/m^3、1.2~1.5 kg/m^3、0.9~1.2 kg/m^3。  相似文献   

4.
高吸水树脂改性混凝土研究   总被引:8,自引:0,他引:8  
叙述了锆盐交联的部分磷酸化的聚乙烯醇高吸水树脂对混凝土性能的影响,在混凝土中添加具有合适的交联密度和可解离磷酸根含量的此类树脂,用量在2.4%~3.0%时,可大大改善混凝土的耐蚀性,抗压强度可提高25%以上,收缩率明显降低  相似文献   

5.
在传统桥梁现浇混凝土配合比的基础上,通过增加羟丙基甲基纤维素(HPMC)、高吸水饱和树脂(SAP)和聚丙烯纤维(PP)的方法,分析了其对混凝土泌水及抗裂性能的影响。结果表明:HPMC在0.01%~0.02%范围内可提高混凝土的抗裂与保水性能;SAP在混凝土中的最佳掺量为0.1%,HPMC,SAP,PP三者复配效果最佳。  相似文献   

6.
掺有机硅防水剂混凝土抗Cl-侵蚀的研究   总被引:1,自引:0,他引:1  
很多混凝土结构由于氯离子的侵蚀而破坏,增强混凝土抵抗氯离子侵蚀的能力有助于提高混凝土耐久性.在结构建造时把内掺型防水剂作为混凝土的一种组分加入,使混凝土整体是斥水的,即使出现裂缝,裂缝表面也是防水的,可有效抵抗氯离子侵蚀.本文试验中所用的防水剂为内掺型有机硅防水剂.结果表明,在裂缝宽度不大于0.4mm时,内掺法防水处理...  相似文献   

7.
文中研究了芦苇秸秆纤维长度、纤维掺量、水泥土龄期等因素,及其对芦苇秸秆水泥土的无侧限抗压强度的影响.试验结果表明:芦苇秸秆纤维的掺入可提高水泥土的无侧限抗压强度,在水泥掺入比为15%的情况下,芦苇秸秆水泥土的最优加筋条件为纤维长度5mm、纤维掺量0.1%;当纤维长度大于5mm或纤维掺量大于0.1%时,芦苇秸秆水泥土的无...  相似文献   

8.
《Planning》2019,(2)
在收集、研究前人研究成果的基础上,应用土壤水蚀模型和流域泥沙输移比初步建立了泥石流坡面侵蚀物源量计算模型,同时列举了降雨侵蚀力因子、土壤可蚀性因子、地形因子及植被覆盖因子等水蚀因子的标准算法和经验算法,具有较强的理论依据,对泥石流坡面侵蚀物源量计算具有借鉴意义。  相似文献   

9.
在闽东南地区,因花岗岩球状风化诱发的边坡滚石灾害问题十分突出,通过研究滚石运动轨迹来确定合理的坡形坡率是防范边坡滚石灾害的基本对策。对边坡坡率、平台宽度和坡面特征三个基本参数变化条件下典型边坡滚石运动轨迹进行定量计算和对比分析,得到了以下结论:1植被覆盖的土质坡面较光滑坚硬的岩质坡面具有明显的"消能"效应;2加宽平台及增加平台植被可有效阻碍滚石运动;3放缓坡率能延缓滚石启动变形,并能明显控制滚石运动距离;4宽平台结合上缓下陡的坡形坡率设计是控制滚石灾害的优选方案。  相似文献   

10.
本文通过对4种不同配比混凝土试件进行圆环试验,研究粉煤灰和聚丙烯纤维对混凝土收缩和抗裂性能的影响。结果表明,粉煤灰的掺入可延缓混凝土收缩裂缝的形成,但后期一旦形成较大裂缝,则发展较快;聚丙烯纤维在混凝土开裂时能够承担一部分拉应力,使内钢环应变曲线呈缓慢下降趋势;掺加纤维后,混凝土的各项抗裂指标显著提高,最大和平均裂缝宽度、裂缝总面积等均大幅降低,裂缝控制率达97.6%。  相似文献   

11.
 通过对植被护坡系统水分动态平衡的分析,提出岩石边坡植被护坡系统根层土壤贮水量的基本要求。采用现场降雨试验等方法研究岩石边坡植被护坡系统水分运移的规律,对影响植被护坡系统水分平衡的根层土壤初始贮水量、植被截留量、坡表径流量、边坡坡角、坡表蒸散量及根层土壤萎蔫贮水量等因子进行分析。试验结果表明:若客土配比合理,其渗透性能良好,客土能在较短的时间内获得较大的贮水量,客土中添加适量保水剂、泥炭可明显减缓客土层水分的蒸散,此外,客土中添加保水剂还可降低客土的萎蔫持水量,使客土层中更多的水分成为可供植物利用的有效水;覆盖良好的坡面植被对降雨的截留量不可忽视;为提高降雨的入渗量,须选择适宜的边坡坡角。研究成果可为岩石边坡植被护坡系统的水分平衡及控制提供依据。  相似文献   

12.
植被增加边坡降雨入渗对边坡稳定性影响研究   总被引:2,自引:0,他引:2  
植被根系提高土壤渗透性和抗侵蚀性,植被盖度越大径流起始时间越长,植被提高边坡的入渗率和减少土壤流失相互促进,共同作用的结果是保持水土,所以植被增加边坡降雨入渗的作用是十分显著的.大多数植物的根系分布在浅层,根际区土壤储水能力强,由于植被对根际区下层土壤的渗透性影响不大,而且认为植被对降雨入渗对根际区土壤水分的影响明显,而对边坡根际区下层土壤水分影响不明显,植被增加边坡降雨入渗不影响边坡深层稳定性.  相似文献   

13.
《Soils and Foundations》2007,47(2):207-217
It is generally thought that vegetation has a stabilization effect on a slope; however, very limited quantitative field data are available for verifying this perception. In order to improve our understanding on the vegetation effect on rainfall infiltration and hence on slope stability, a well-instrumented field study was carried out on an unsaturated expansive soil slope in China. The field program consisted of two neighboring monitoring areas (both 16 m wide by about 30 m long): namely a bare area and a naturally grassed area (real slope). Artificial rainfall events were produced in succession in the two areas with a specially-designed sprinkler system. In this paper, the relevant monitored results from the two areas are directly compared and discussed. Prior to the artificial rainfall, the measured higher initial soil suction in the grassed area than that in the bare areas was attributed to the evapo-transpiration effect of the grass. During the rainfall, the presence of the grass greatly increased the infiltrability of the upper soil layer and delayed the onset of surface runoff. The observed delayed responses (i.e., about 3 days) of surface runoff, soil suction and water content to the rainfall in the grassed area was about twice the duration of the delayed response in the bare area (i.e., about 1.5 days). The influence of the simulated rainfall on the changes of soil suction and water content in the grassed area was found to be more significant and about 1.5 m deeper than that in the bare area. The greater depth of influence observed in the grassed area may be attributable to the greater depth of open cracks due to the evapo-transpiration effect of grass.  相似文献   

14.
通过对同尺寸的单块素土坯及掺和麦秸秆的单块土坯的各向抗压试验获得了素土坯和掺和麦秸秆土坯的抗压强度及受力破坏形态,总结了单块土坯抗压试验的试验过程及试验现象。得到荷载—位移曲线后,评估掺和麦秸秆对土坯抗压承载能力的影响及得出了麦秸秆的最优掺量。掺和适量的麦秸秆能提高土坯的抗压强度及应变能力。从本试验研究得出的结果,为土坯砌体试验和土坯墙片试验提供基本力学性能数据。  相似文献   

15.
介绍在高陡边坡上充分利用"防护网+防水纤维层+(种子、肥料、土壤、改良剂、保水剂)+无纺布"来保护植被及其生长条件,为高陡岩质边坡实施人工绿化提供了可能,以充分利用植被根系的护坡加固作用和绿色植物的环境绿化美化功能,将工程治理与环境保护和改造融为一体。  相似文献   

16.
《Soils and Foundations》2023,63(1):101248
Runoff generated by heavy rainfall in natural catchment area and caused by ditch clogging in artificial structure increases the instability of the slope. The effects of runoff are usually neglected in traditional rainfall-induced slope failure analysis. In order to consider the effects of runoff on the slope instability, this study attempts to simulate the runoff, infiltration and slope instabilities simultaneously on both wide/narrow area. For this purpose, this study firstly proposes a coupled model of surface flow, subsurface flow, and soil mechanics based on Diffusion wave equations, Richards’s equation, Green-Ampt infiltration capacity model, and local factor of safety approach in wide area simulation. Next, snowmelt and surface grass layer are additionally considered in narrow area simulation. Finally, the proposed coupled model is applied to two slopes at Nissho Pass and Kuromatsunai in Hokkaido, Japan. The slope instabilities assessment approach provides an effective method for simulating runoff and slope instabilities. In wide area, the distribution map of the factor of safety has significant implications for precisely determining the dangerous spots and accurately releasing the warning information. In narrow area, the slope disaster points caused by the ditch clogging are extracted and effect of grass layer on slope stability assessment is demonstrated. The construction and maintenance of the drainage system can be re-designed to ensure all the surface flow caused by the precipitation drain out smoothly.  相似文献   

17.
Storm water management issues facing the Texas Department of Transportation in the late 1980s led to the development of a coordinated research program with the Texas Transportation Institute. Researchers developed methodologies for evaluating the field performance of various erosion control technologies of the most widely used products within the Department's construction and maintenance operations. From these methodologies, the Hydraulics and Erosion Control Laboratory was designed and constructed. Currently, participants include private industry (manufacturers of erosion control products), transportation researchers (TTI), and the public sector (TxDOT).The results reported in this paper reflect 2 years of erosion-control blanket research. The study objectives were to determine the effectiveness of erosion-control blankets on the growth of warm-season perennial grasses and their ability to prevent sediment loss in a sloped condition.The laboratory simulates the highway environment with the sloped plots (6 m in width) located on an earthen embankment that is 300 m in length and 6.75 m in height (94 ft. by 22 ft., vertically). A randomized experimental design was replicated on two soil types (sand and clay) for each slope condition (3:1 or 2:1) with a control.In general, the results indicate better combined results relating to sediment retention and vegetation establishment performance for erosion-control blankets on sandy soils (noncohesive) regardless of slope condition (3:1 or 2:1) or material type. A minimum of 50% more sediment was retained on the sandy treatment plots and a 45% more vegetation coverage was achieved compared with the control plots. When analyzed by material type related to performance, excelsior, synthetic blends, and straw/coconut blends performed the best. For clay soils (cohesive), regardless of slope condition (3:1 or 2:1), the combined results indicate a minimum of 75% more sediment was retained and a minimum of 5% more vegetation establishment was achieved compared with the control plots. When analyzed by material type related to performance, excelsior, straw, and straw/coconut blends performed the best.  相似文献   

18.
《Soils and Foundations》2014,54(3):417-425
Green technology, an integrated design approach that combines vegetation and engineering design methods, can be applied to improve slope stability. Orange Jasmine is a small tropical evergreen shrub which has deep root systems and is considered to be a drought-tolerant plant that adapts well to a wide range of climatic and soil conditions. It can also grow in infertile soils, limestone soils or loam. Vetiver grass has been widely cultivated in many tropical and subtropical regions of the world for soil and water conservation, land rehabilitation, and embankment stabilization. Vetiver grass has deep roots (2–4 m) and adapts well under extreme conditions of temperature, soil, moisture, soil acidity, and alkalinity. The role of Orange Jasmine and Vetiver grass in minimizing rainwater infiltration, for improving the stability of slopes, was investigated on a soil slope in Singapore with its tropical climate. Two slope sections, covered with Orange Jasmine and Vetiver grass, were instrumented with tensiometers, installed at different depths within the slope, and a rainfall gauge. The instruments were connected to a real-time monitoring system to study the pore-water pressure, the rainfall, and the groundwater level in the slope throughout a one-year period. The pore-water pressure characteristics within the slope sections covered with Orange Jasmine and Vetiver grass are analyzed and presented in this paper. The analyses indicate that both Orange Jasmine and Vetiver grass played a significant role in reducing rainwater infiltration into the slope, minimizing the loss of matric suction, and hence, the shear strength of the soil during rainfall and, as a result, maintained the stability of the slope. Vetiver grass and Orange Jasmine appeared to be similar in effectiveness in terms of reducing the rainwater infiltration into the slope.  相似文献   

19.
Infiltration of runoff at the plot-scale is increasingly considered as an effective tool to improve urban water management. As a consequence, authorities in different countries adopt regulations prescribing the infiltration of stormwater in new developments. Here we apply a simple sizing procedure for plot-scale infiltration facilities to examine the consequences, in terms of implementation, of typical regulation standards. Considering the relevance of different parameters in the sizing of infiltration facilities, local hydraulic conductivity emerges as the most relevant factor. Because of the importance of local infiltration capacity, current regulation standards based on a single constraint applied everywhere can require from developers highly different compliance efforts and can prove ineffective for stormwater management. We argue that regulations fixing constraints according to plot-scale soil characteristics are feasible and more effective.  相似文献   

20.
生态绿地控制初期雨水径流污染的研究   总被引:2,自引:0,他引:2  
研究了生态绿地对初期雨水径流污染物的控制效果。生态绿地通过滤层过滤、植物吸收和生物降解的多重作用,实现了对SS、TN和TP的高效去除,而过滤介质和植物根系的缓冲作用,使得对CODMn保持了比较稳定的去除效果。生态绿地通过对初期高污染的雨水径流进行收集及后期洁净雨水的溢流实现了对雨水径流污染物的高效控制,对每场降雨中CODMn、TP、TN和SS的平均控制量分别为41.0、0.697、24.5和239mg/m2。生态绿地收集的雨水通过毛细作用到达表层土壤,提高了土壤的含水率,供给植物生长需求,对降雨量的利用率可达20%。生态绿地在有效控制雨水径流污染物的同时,还实现了对雨水的高效利用,可广泛应用于雨水径流面源污染的控制。  相似文献   

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