ブックタイトル竹中技術研究報告書No70

概要

竹中技術研究報告書No70

TAKENAKA TECHNICAL RESEARCH REPORT No.70 2014竹中技術研究報告No.70 2014Fig. 21Load sharing among piles, deep mixing walls and soilin tributary areaFig. 22 Load sharing of effective load among piles, deep mixingwalls and soil in tributary areaof the effective load carried by the soil decreased very slightly to 0.20, while the ratio of the effective load carried by the DMWincreased significantly to 0.13. Thereafter, the ratio of the load carried by the piles to the effective load increased slightly to0.7 0 and the ratio of the effective load carried by the DMW to the effective load increased only slightly just before E.O.C.,while the ratio of the effective load carried by the soil decreased considerably from 0.21 to 0.17 in that term. This indicates thata small amount of load transfer from the soil to the piles occurred due to consolidation settlement of the soil.After E.O.C., the load sharing among the piles, the DMW and the soil was quite stable. Namely, the ratio of the effectiveload carried by the piles to the effective load varied from 0.69 to 0.72, and the ratio of the effective load carried by the soil tothe effective load varied from 0.14 to 0.16 while that carried by the DMW to the effective load was 0.14.4 LONG-TERM SETTLEMENTS AND LOAD SHARING4.1 Foundation SettlementsFigure 23 shows the foundation settlement versus elapsed time relationship for the seven structures, where line (e) to (k)refer to buildings (e) to (k) shown in Fig. 1. In these structures, the vertical ground displacements just below the rafts weresuccessively measured from the beginning of the construction to 17 to 102 months after E.O.C. While the relationship for thesix structures were originally shown in the previous paper (Yamashita, 2012), the data for the 12-story office building werenewly added and those for the 13-story hospital were updated from those in the previous paper (Yamashita et al., 2011a). Themeasured settlements reached 18 to 27 mm at the end of the observation, while those at E.O.C. were 12 to 23 mm. Themaximum value of 27 mm for the hadron experimental hall included the increase in settlement due to the strong seismic motionduring the 2011 off the Pacific coast of Tohoku Earthquake. It was found that the measured foundation settlements at the end ofthe observation were within a limited range, and around 25 mm (one inch).4.2 Load Sharing between Piles and RaftFigure 24 shows the relationship between the ratio of the load carried by the piles to the effective load in the tributary area ofFig. 23 Measured foundation settlements vs. time38