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101.
The research area that is in the north of Istanbul (Turkey) and it is a land of open pit coal mining residuals reclaimed and turned to forest in 1988–1989. The materials that are open pit mine spoils are formed by sandy loam, sandy clay loam, heavy loam and clay (noncalcareous Pliocene I sediments). Pseudoacacia (Robinia pseudoacacia), Maritima Pine (Pinus pinaster) and Stone Pine (Pinus pinea) are planted on these materials. The aims of this research were to determine the strength of the material provided by tree roots and evaluate the performance of the forestation practices at lands especially where open pit coal mining spoil (residual) materials piled up. The research has been performed at two stages. The first one was hydro-mechanical effect concerned about material moisture depletion as a result of transpiration and the second one was bio-mechanical effects due to strength parameters of the roots and their growth pattern within the material. All results were evaluated in relation to tensile strength and displacement curves due to pre and post failure behaviors of materials and root systems. The results showed the increase of the displacement of the material was the significant indicator of the bio-mechanics tensile strength of the material provided by the tree roots. The fast growing type of tree roots have stabilized the material up to a depth for 80–100 cm by covering the coal residual materials within 12 years. 相似文献
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本文着重讨论了重力勘探教材中关于倾斜脉的△g、V_(xz)、V_(zz)理论公式及二次微商理论曲线的正误问题。文中给出了无限延深倾斜脉的准确的 V_(xz)及 V_(zz)理论曲线,并且指出应该充分地利用 V_(xz)V_(zz)异常特征解释推断脉的倾向. 相似文献
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The seasonal range of sea temperature on the New Zealand shelf 总被引:1,自引:1,他引:0
D. M. Garner 《新西兰海洋与淡水研究杂志》2013,47(2):201-208
Sea water temperatures measured over the New Zealand continental shelf in summer and winter 1967 are compared and discussed. 相似文献
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Seismic performance of an unreinforced masonry building: An experimental investigation 总被引:1,自引:0,他引:1
This paper presents the results of an experimental investigation carried out to investigate the seismic performance of a two storey brick masonry house with one room in each floor. A half‐scale building constructed using single wythe clay brick masonry laid in cement sand mortar and a conventional timber floor and timber roof clad with clay tiles was tested under earthquake ground motions on a shaking table, first in the longitudinal direction and then in the transverse direction. In each direction, the building was subjected to different ground motions with gradually increasing intensity. Dynamic properties of the system were assessed through white‐noise tests after each ground motion. The building suffered increasing levels of damage as the excitations became more severe. The damage ranged from cracking to global/local rocking of different piers and partial out‐of‐plane failure of the walls. Nevertheless, the building did not collapse under base excitations with peak ground acceleration up to 0.8g. General behaviour of the tested building model during the tests is discussed, and fragility curves are developed for unreinforced masonry buildings based on the experimental results. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
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