Dynamic soil arching in piled embankment under train load of high-speed railways.

Autor: Niu, Tingting, Yang, Yule, Ma, Qianli, Zou, Jiuqun, Lin, Bin
Předmět:
Zdroj: Earthquake Engineering & Engineering Vibration; Jul2023, Vol. 22 Issue 3, p719-730, 12p
Abstrakt: Piled embankments have many advantages that have been applied in high-speed railway construction engineering. However, the load transfer mechanism of piled embankments, such as soil arching and tension membranes, is still unclear, especially under dynamic loads. To investigate the soil arching and tension membrane under dynamic train loads on high-speed railways, a large-scale piled embankment model test with X-shaped piles as vertical reinforcement was performed, in which twenty-eight earth pressure cells were installed in the piled embankment and an M-shaped wave was adopted to simulate the high-speed railway train load. The results show that dynamic soil arching only occurs when two bogies of a carriage pass by and disappears at other times. The dynamic soil arching and membrane effect are the most significant under the concrete base. The arching height, stress concentration ratio and pile-soil load sharing ratio have a minimal value at 25 Hz. The dynamic soil arching degrades severely at 25 Hz, whose height at 25 Hz is only 0.35 times that at 5 Hz. The arching height fluctuates over a narrow range with increasing loading amplitude. The stress concentration ratio and the pile-soil load sharing ratio increase monotonically as the loading amplitude increases. [ABSTRACT FROM AUTHOR]
Databáze: Complementary Index