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991.
Mubarakshina R. R. Lapaeva V. V. Kashcheev R. A. Zagretdinov R. V. Nefedyev Y. A. Andreev A. O. 《Astronomy Reports》2021,65(3):224-232
Astronomy Reports - This study is focused on the analysis of data of the long-term latitude observations and the Global Navigation Satellite System (GNSS). The latitude observations include... 相似文献
992.
Doklady Earth Sciences - This paper analyzes measurement data on the ionic composition of the upper atmosphere at altitudes of 810–830 km in the period from 2009 to 2018; the measurements... 相似文献
993.
Costa Lus R. D. Hugman Rui T. Stigter Tibor Y. Monteiro Jos Paulo 《Hydrogeology Journal》2021,29(7):2501-2516
Hydrogeology Journal - The dynamics related to evolution of nitrate-contaminated groundwater are analyzed with focus on the impact of intrinsic aquifer properties, agricultural activities and... 相似文献
994.
Landslides - Assessment of the spatial probability of future landslide occurrences for disaster risk reduction is done through landslide susceptibility modelling. In this study, we investigated the... 相似文献
995.
Rytsk E. Yu. Tolmacheva E. V. Velikoslavinsky S. D. Kuznetsov A. B. Rodionov N. V. Andreev A. A. Fedoseenko A. M. 《Doklady Earth Sciences》2021,496(2):146-150
Doklady Earth Sciences - The results of U–Pb geochronological (SIMS) study of zircons from granitoids of the Konstantinovskii Stock located 6 km from the Sukhoi Log gold deposit are reported.... 相似文献
996.
Acta Geotechnica - Suffusion is a complex phenomenon characterized by a selective migration of the fine particles under the effect of three coupled processes: detachment, transport and possible... 相似文献
997.
Properly designed precast concrete cladding could potentially provide lateral stiffness, ductility, and energy dissipation for an overall building structure, especially during earthquakes. This paper describes a set of advanced connections that take advantage of the interaction between facade panels and structure (mainly due to horizontal interstorey drift) to dissipate energy, thereby reducing the response of the main structure. The results of an experimental program to characterize the hysteretic behaviour of advanced connections are presented. Design equations for the advanced connections are then calibrated against the test results, and the corresponding design charts are presented. It is anticipated that this research will lead to innovative ways of viewing the entire cladding system of a building. 相似文献
998.
999.
Tension-Only Concentrically Braced Frames (TOCBF) exhibit deteriorating pinched hysteretic behaviour during strong earthquakes. Slender braces transit between an elastic buckling state, a restraightening state, in which they carry almost no load, an elastic tensile loading state as they are suddenly taut and, finally, a tensile yielding state. It has long been suspected that the sudden increase in tensile forces in the braces of TOCBSF creates detrimental impact loading on the connections and other structural elements. No experimental evidence, however, has been provided so far to confirm, or to quantify, this impact phenomenon. This paper addresses this issue through shake table tests of half scale, two-storey, TOCBF models. By normalizing the hysteresis loops of braces obtained from shake table tests to the yield strength of steel obtained from quasi-static tests, the increase in tensile forces in the braces was obtained. Results of dynamic tensile tests on steel coupons under similar strain rates as observed during the shake table tests showed that this increase in tensile forces is not the result of impact, but is rather caused by a yield strength increase of the steel under high strain rate. A procedure is proposed to estimate and account for this increase in tensile forces in the braces at the design stage. 相似文献
1000.
The mathematical base of the double porosity concept, consisting of the continuity and equilibrium equation respectively, is briefly reviewed. A quasi-steady-state transfer function, the so-called leakage term, is used. Important aspects of the developed code, based on the double porosity theory, are presented together with two hypothetical example problems. The resulting trend of the settlements are compared to those from previous work and was found to be significantly different. However, the implications are that the present study exhibits a more realistic prediction for the settlement. 相似文献