孔洞開挖後軟弱地盤之沉陷行為

• Main Author: 施俊如
• Other Authors: 張惠文
• Format: Others
• Language: zh-TW
• Published: 2000
• Online Access: http://ndltd.ncl.edu.tw/handle/76539297204688375401

碩士 === 國立中央大學 === 土木工程研究所 === 88 === When a cavernous ground was compressed, the settlement of the ground consisted of the immediate settlement, consolidation and vertical displacement due to the deformation of the caves. In this research, the Taipei-Basin silty clay was used to fabricate the remolded soil samples with cavities, and the odometer test was conducted to simulate the displacement behavior of the weak soil layer after excavation. Assuming that the cavity was a new material of the soil sample, the test results could be analyzed. From the results of the tests, it was revealed that the compression index (Cc) tends to increase with the cavity diameter in the soil sample. The variation of the values of the coefficient of volume change (mv) was large in the initial loading stages. With increasing loading stress, this variation decreased to a smaller range. It was also found that the settlement of the soil was affected by the stiffness of the sample and the diameter of the cavity. With larger preconsolidation pressure, the soil was stiffer and the effects of the cavity diameter became less. The deformation of the cavity was obvious when the immediate settlement occurred, but became unapparent during the consolidation progress.