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931.
U.?M.?Rao?KaranamEmail author S.?K.?Dasyapu 《Geotechnical and Geological Engineering》2005,23(3):297-308
Rock bolts are widely used for rock reinforcement in hard-rock mining and civil engineering since a long time. However the use of fully grouted rock bolts and cable bolts is limited in coal mines. In order to improve performance of the rock bolts as a supplementary roof support system for any type of roof condition in coal measured formations, it is necessary to have a good understanding of the behavior of the bolt–grout and grout–rock interactions as well as the mechanism of load transfer in rock bolts.As the performance of grouted bolts depends on bond strength, extensive laboratory pullout as well as pushout tests were conducted in the present investigations with the variations in the bolt diameters, length and cement–water mixing ratios of grout. The load–displacement curves were developed and were verified with the numerical results obtained from finite element analysis using ALGOR software.Numerical models were validated for pushout tests and a detailed analysis was carried out to know the displacement, stress, strain distribution along the bolt. 相似文献
932.
933.
岩石的应变组构型式与岩石成分、变形环境和应变过程有着密切关系。北瓦沟地区低角闪岩相条作下的长英质岩石,表现脆性、韧性和韧脆性过渡,因而在剪切作用过程中形成了相应的应变组构型式,即脆性应变组构、韧性应变组构和脆-韧性应变组构。而且随着应变过程的发展,应变组构也表现出一定的演化规律。 相似文献
934.
通过野外对三座庙序列侵入岩的岩体平面与剖面形态、岩体的内部构造、岩石与围岩的构造型式、接触带的度形特征等宏观地质特征的研究,推测岩体侵入位机制为强力挤入方式定位,即气球膨张式。笔者运用岩石的有限应变测量原理和方法,结合岩组分析及流变学、现代变形理论,对三座庙序列的侵入岩岩石做了有限应变测量和岩组分析工作,所得定量资料为确定岩体的浸位机制提供了理论依据。三种岩石有限应变测量,即:算术平均法、长短轴法、Rf/φ曲线法的富林指数k值均在0相似文献
935.
936.
937.
WANG Yuwang WANG Jingbin WANG Lijuan WANG Yong TU Caineng Beijing Institute of Geology for Mineral Resources Beijing Key Laboratory of Mineral Resources Research Institute of Geology Geophysics Chinese Academy of Sciences Beijing Xinjiang Kalatongke Cu-Ni Mine Fuyun Xinjiang 《《地质学报》英文版》2004,78(2):396-403
On the basis of the study on the REE geochemistry of the ore minerals and host rocks of the Kalatongke Cu-Ni deposit, Xinjiang, it is indicated that the major ore minerals, sulfides, were sourced from the host mafic-ultramafic magma. Characterized by low REE content of sulfide, such a Cu-Ni sulfide deposit occurring in the orogen is obviously different from that on the margin of the craton. Because the mafic-ultramafic rocks from the Cu-Ni sulfide deposit occurring in the orogen is water-rich and the REEs of some sulfides show a particular "multiple-bending" pattern, which suggests coexistence of multiple liquid phases (fluid and melt), the sulfide melt possibly contains a great deal of hydrothermal fluids and increasingly developed gases and liquid-rich ore-forming fluids after the main metallogenic epoch (magmatic segregation stage). 相似文献
938.
939.
Detailed studies indicate that Kangxian-Pipasi-Nanping tectonic zone is a complicated mélange zone which includes many tectonic
slabs of different origins. Ophiolite (MORB-type basalt), oceanic island tholeiite and alkaline basalt have been identified.
Moreover, this tectonic mélange zone is eastward connected with the Mianlüe suture zone. The deformation characteristics,
consisting components and volcanic rock geochemical features for the Kangxian-Pipasi-Nanping tectonic mélange zone are much
similar to those of the Mianlüe suture zone and Deerni ophiolite. Therefore, the Kangxian-Pipasi-Nanping tectonic mélange
zone should be the westward extension part of the Mianlüe suture zone. It indicates that the Mianlüe suture zone had extended
to the Nanping area. 相似文献
940.
SARAH M. SPRINGMAN LUKAS U. ARENSON YUKO YAMAMOTO HANSRUEDI MAURER ANDREW KOS THOMAS BUCHLI GUIDO DERUNGS 《Geografiska Annaler: Series A, Physical Geography》2012,94(2):215-243
This paper recognizes the contribution of Professor Wilfried Haeberli for his inspiration and leadership in the field of permafrost science and his generous encouragement, both direct and indirect, to the ETH Researchers who have, through him, endeavoured to contribute to this fascinating research area. The multidisciplinary investigations described in this paper have focused on three rock glaciers, Muragl, Murtèl‐Corvatsch and Furggwanghorn, all of which have been subject to a varying degree of prior study, and which are continuing to attract new generations of researchers to understand and explain the processes and predict future behaviour. This paper marks a stage at which it is possible to summarize some advances in the state of the art and associated innovations that can be attributed to early motivation by Wilfried Haeberli and offers a tribute as well as gratitude for his ongoing feedback and advice. Some thoughts on the development of thermokarst due to water ponding and flow, and a conceptual model of geotechnical mechanisms that aim to explain some aspects of rock glacier kinematics, are also introduced. 相似文献