STORURDI: A LATE HOLOCENE ROCK-SLOPE FAILURE (STURZSTROM) IN THE JOTUNHEIMEN, SOUTHERN NORWAY     

BY PETER WILSON 《Geografiska Annaler: Series A, Physical Geography》2009,91(1):47-58

An extensive accumulation of rock debris at the mouth of Urdadalen in the Jotunheimen, southern Norway, is interpreted as the deposit of a rock-slope failure (sturzstrom). This is the first large-scale rock-slope failure to be recognised in the Jotunheimen but is unlikely to be the only one. The debris descended to the valley floor, passed across the valley axis and moved 40 m up the opposite side of the valley. Some debris passed over the lip of Urdadalen and now forms a boulder tongue that extends for c. 800 m into Utledalen. A maximum velocity of 80 m s⁻¹ for debris movement from crest of hillside to toe of boulder tongue has been estimated, and a minimum velocity of 28 m s⁻¹ was required for the debris to run up the opposite side of Urdadalen. The degree of boulder hardness/weathering as determined by Schmidt hammer suggests the sturzstrom occurred in the Late Holocene (1.825 ± 0.76 cal. ka bp ), during a period of climatic deterioration. The localised geomorphological impact of the failure event has been to dam the valley and create a small lake, to cause valley widening, to produce a north-facing hillside embayment at 1200–1400 m above sea level with the potential to collect and retain snow that might, in future, lead to niche glacier development and cirque initiation, and to provide a large volume of rock debris for entrainment and onward transport in future glacial cycles.  相似文献   

套管、潜孔锤复合性钻进工艺在河床卵砾石层中的应用     

许厚材 《吉林地质》2000,19(3):83-86

在卵砾石层中钻进,采用常规钻进方法效果欠佳。本文介绍的采用套管钻进和潜孔锤钻进相结合的复合性钻进工艺,有效地解决了在卵砾石层中钻进的难题。  相似文献   

多工艺冲击回转钻进技术的新拓展   总被引：1，自引：0，他引：1  

张勇  蒋荣庆 《世界地质》2000,19(3):291-294

多工艺冲击回转钻进技术具有钻进效率高、孔内事故少、钻头寿命长、设备质量轻等一系列优点,近年来愈来愈受到国内外钻探界的关注。全面介绍了该项工程技术在我国工程地质勘察、锚固工程、大直径基岩桩孔工程、水文水井钻凿以及非开挖铺设管线中的应用现状。由于紧密地与生产实际结合,使得冲击回转钻进的新工艺、新方法日臻完善。我国钻探界已将该项技术应用于石油天气气钻井、大陆科学钻探、水下钻孔、干旱岩深地区水井钻凿等工程  相似文献   

爆破技术在冲孔灌注桩中的应用   总被引：2，自引：0，他引：2  

胡文年 《水文地质工程地质》2000,27(4):49-50,54

本文介绍爆破技术在处理冲孔灌注桩卡锤事故中应用以及利用松动爆破加快冲孔灌注桩施工的工程实践。  相似文献   

Numerical modelling of large deformations associated with driving of open‐ended piles     

D. S. Liyanapathirana  A. J. Deeks  M.F. Randolph 《国际地质力学数值与分析法杂志》2000,24(14):1079-1101

This paper presents a ‘Eulerian‐like’ finite element technique to simulate the large accumulated displacements of piles subjected to multiple hammer blows. For each hammer blow, results are obtained using a standard small strain finite element model and, at the end of each hammer blow, material flow is taken into account with reference to a fixed finite element mesh. Residual stresses calculated at the Gauss integration points of the deformed finite element mesh are mapped on to the fixed finite element mesh, and these stresses are used as initial stresses for the next hammer blow. At the end of each hammer blow, stiffness and mass matrices are recalculated for the volume of material remaining inside the fixed finite element mesh. Results obtained with and without allowing material to flow through the fixed mesh are compared for several hammer blows. Build up of residual stresses, soil flow and yielded points around the pile are presented for plugged, partially‐plugged and unplugged piles. Using the new finite element technique, the driving of a pile from the soil surface is studied. The ability to analyse this and other large deformation problems is the main advantage of the new finite element technique. Copyright © 2000 John Wiley & Sons, Ltd.  相似文献   

增大液动射流式冲击器单次冲击功的试验研究   总被引：3，自引：0，他引：3  

菅志军  殷琨  蒋荣庆 《吉林大学学报(地球科学版)》2000,30(3):303-306

:试验结果发现 ,当行程加大时 ,获得较高的冲锤末速度 (5 .43m/s) ,单次冲击功 34 6 .45J。当活塞运动所需瞬时流量已大大超过了水泵供水的供给量时 ,冲击器仍能稳定地工作 ,这体现了射流冲击器作为一开放的系统所特有的流量可自动补偿的优点。射流冲击器对负载的适应能力较高 ,且在大行程条件下 ,增加锤重可较大幅度地提高单次冲击功。  相似文献   

Field estimate of paleoseismic slip on a normal fault using the Schmidt hammer and terrestrial LiDAR: Methods and application to the Hebgen fault (Montana,USA)          下载免费PDF全文

Alexander Tye  Timothy Stahl 《地球表面变化过程与地形》2018,43(11):2397-2408

The weathering characteristics of bedrock fault scarps provide relative age constraints that can be used to determine fault displacements. Here, we report Schmidt hammer rebound values (R‐values) for a limestone fault scarp that was last exposed in the 1959 Mw 7.3 Hebgen Lake, Montana earthquake. Results show that some R‐value indices, related to the difference between minimum and maximum R‐values in repeated impacts at a point, increase upward along the scarp, which we propose is due to progressive exposure of the scarp in earthquakes. An objective method is developed for fitting slip histories to the Schmidt hammer data and produces the best model fit (using the Bayesian Information Criterion) of three earthquakes with single event displacements of ≥ 1.20 m, 3.75 m, and c. 4.80 m. The same fitting method is also applied to new terrestrial LiDAR data of the scarp, though the LiDAR results may be more influenced by macro‐scale structure of the outcrop than by differential weathering. We suggest the use of this fitting procedure to define single event displacements on other bedrock fault scarps using other dating techniques. Our preliminary findings demonstrate that the Schmidt hammer, combined with other methods, may provide useful constraints on single event displacements on exposed bedrock fault scarps. Copyright © 2018 John Wiley & Sons, Ltd.  相似文献   

风动冲击器活塞冲击末速度的有限元研究   总被引：5，自引：1，他引：4  

詹军  殷琨  于清杨  曾建华 《煤田地质与勘探》2003,31(6):58-60

风动冲击器活塞的冲击末速度决定了冲击器的工作性能。本文运用有限元分析软件ANSYS建立了活塞分析的有限元模型,对不同冲击末速度下活塞的应力应变进行了分析研究,得出活塞最大应力随冲击末速度增大而增大,但变化为非线性,设计和使用中应严格控制冲击末速度的结论。   相似文献   

液动射流式冲击器性能参数影响规律的研究   总被引：1，自引：0，他引：1  

菅志军  桑路  王保丰  王清 《煤田地质与勘探》2002,30(5):58-60

本文根据计算与模拟实验资料,分析了液动射流式冲击器的泵量、泵压、冲锤质量、冲击行程等,对冲击器性能参数的影响规律、电算模拟数据绘制了相应的影响规律曲线,其结果与室内模拟实验的结果吻合,为冲击器的设计与使用提供了依据。   相似文献   

跟管钻进在大口径页岩气井浅部复杂地层中的应用 ——以黔水地1井导管段为例          下载免费PDF全文

郭军  王超技  李岩  苑坤  王文彬 《探矿工程》2020,47(5):22-26

桂中-南盘江地区的浅部地层裂隙、溶洞发育,破碎带多,井漏、井垮严重,泥浆护壁钻进成孔难度较大。针对该类地层,首次将跟管钻进技术引入大口径页岩气井钻探——黔水地1井导管段钻探,有效地解决了该井导管段的成孔难等问题。并通过系统总结该技术在黔水地1井工程施工中的实际应用情况,为今后类似工程提供了宝贵经验和建议。  相似文献