Central Artery/Tunnel Project Excavation Induced Ground Deformations

Sequential Measurement and Analysis of Large Underground Retaining Structures by Diaphragm Wall Anchor for the Spring Area

“…Advances in Civil Engineering in Jinan and those reported in literature show that these study data are consistent with the stiff clay and silty sand and the stiff to hard clay [25,46]. e data also fall within O'Rourke [29] profile for middle-dense to dense sand and Hashash et al [21] profile for medium stiff clay, but far away from Zone III of Peck [10] for very soft to soft clay. e Chicago glacial clay falls mainly within Zone I of Peck [10], while the Oslo clay and the sand [25] fall within Zone II of…”

“…From the data points of δ h,max (L1, L2, L3, L4), the results show that the maximum lateral wall deflections in this project are between 0.07 percent and 0.18 percent of the excavation depth. By comparing excavations case histories, it is observed that the maximum lateral wall deflection in this study is similar to that in Dublin-Jervis, London, and Boston due to the similar favorable soil conditions [21,39]. In addition, it was observed that most of the measured δ h,max values in Oslo, Singapore, San Francisco, and Chicago were between 0.67 percent and 2.2 percent of the excavation depth, which were above the range of 0.19 percent and 0.95 percent of the excavation depth measured in Shanghai, Taipei, Iran, and Boston [7,26,40,41].…”

“…e ground settlement decreases rapidly with distance from the excavation pits and the ground settlements in the south segment are greater than the settlements in the west segment. To better understand excavation behaviors in Jinan clay, published case histories [10,21,25,46] are also included for comparison. e comparison of the excavation…”

“…erefore, field monitoring of structure deformations and ground movements plays a vital role in excavation process [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18]. Based on the reported field monitoring data, empirical and semiempirical methods have been identified as an appropriate approaches for the prediction of the excavation deformations [19][20][21][22][23][24][25][26][27][28][29][30][31][32][33][34][35][36][37][38]. ese studies not only have put forward the cognitions of excavations deformations, but also are available to designers who would verify the numerical analysis for complex excavations.…”

“…Figure 14(b) plots the relationships between the normalized ground settlements, δ v /δ v,max , and the distance ratio, d/H e , where δ v � ground settlement along the typical section; δ v,max � maximum ground settlement at the same section behind the diaphragm wall; d � distance away from the diaphragm wall; H e � final excavation depth. In this figure, these case history documents in the literature [3,21,32,34,46] are applied for comparison. From Figure 14(b), it can be concluded that the settlement distribution is bounded by a trapezoidal envelope.…”