THE LOW TEMPERATURE INFLUENCE ON THE DEEP EXCAVATION SUPPORTING SYSTEM
| Autor: | A. V Boyarintsev, M. B Zavodchikova, I. N Zuev, A. V Zhurko, I. S Kamaev |
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| Rok vydání: | 2021 |
| Předmět: | |
| Zdroj: | Construction and Geotechnics. 12:37-53 |
| ISSN: | 2687-0908 2687-0894 |
| DOI: | 10.15593/2224-9826/2021.4.03 |
| Popis: | The practical experience to dig an excavation shows that this process is extended in time and can last for several months engulfing different seasons. An additional accounting of processes occurring in excavation shoring and surrounding soil body during wintertime, when the air temperature drops below zero, is important in such circumstances. This paper describes the results of a field survey of shoring of a deep excavation, soil body and buildings of a surrounding development as the air temperature was changing during the 2020-2021 winter. The survey was performed by monitoring the horizontal and vertical positions of structures using inclinometers and tacheometers. The heaving properties of the clay soil positioned at the excavation digging level were determined in laboratory conditions. The soil frost depth was determined by a numerical simulation of temperature distributions in the "atmosphere-excavation-soil body" system. All this helped understand the nature of the processes observed. The observation results showed that, as the temperature was decreasing, the excavation shoring structures moved into the excavation to a distance of up to 8 mm, and the surrounding development buildings shrank by up to 5 mm. The laboratory study results showed in this context that soils bordering on the shoring structures and foundations of surrounding buildings were not heaving. Thereupon, the strains, which were registered in this actual situation, can not be explained by the frost-heaving phenomenon. The observed strain can be explained by shrinkage of the sprung structure material resulting from a decreasing mean daily air temperature. This effect was confirmed by test results and several surveys presented in the paper. Based on the study conclusions practical guidelines were formulated for excavation digging with consideration to seasonal air temperature fluctuations causing shrinkage and expansion of sprung structures in the shoring structures of excavation of any depth. |
| Databáze: | OpenAIRE |
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