本研究針對各種黏性土壤進行一系列室內壓密試驗，探討不同應 力延時、不同擾動程度，以及不同應力增量比下，土壤壓縮與壓密行 為與標準單向度壓密試驗結果之差異。由實驗結果可知，短應力延時 試驗所得之壓縮與壓密參數值，皆與標準單向度試驗相差甚小，唯一 較為離散之參數為二次壓縮指數，此乃短應力延時試驗之二次壓縮行 為發展尚未穩定所致，但若利用Mesri 之c C Ca 為常數之觀念，則可 避免此一問題。因此短應力延時壓密試驗實值得吾人進一步運用，並 能有效地改善標準壓密試驗耗時過長之缺點。 根據不同性質黏土之壓密試驗結果及相關文獻資料進行整理分 析，提出適用範圍極廣之黏土壓縮及壓密參數迴歸方程式，並將這些 迴歸式與其他學者提出之統計結果進行比較。統計結果顯示壓縮指數 及再壓指數與土樣之初始孔隙比、自然含水量及液性限度具有良好之 線性關係，而c C Ca 及壓密係數則隨塑性指數變化， k C 與初始孔隙比 亦呈正相關。另一方面，本研究亦比較各種參數取決法於求取結果之 差異，並探討其對沉陷分析之影響。上述研究成果可供爾後進行黏土 壓密及沉陷分析選擇試驗與壓縮及壓密參數之參考。 This research conducted a series of consolidation tests on clays with different plasticity index. Its purpose is to investigate the compression and consolidation behavior under different loading duration, loading increment and sample disturbance and the differences with that from standard consolidation test. Test results show that the compression and consolidation parameters of short loading duration test are close to those from standard test except for the secondary consolidation coefficient. It was found that short loading duration test can replace the standard test in reducing long testing time for low plasticity clay. Statistical correlations of the compression and consolidation parameters with physical index of clay are established for alluvial clays based on the test results and data from paper reviews. The compression and consolidation parameters have good linear correlation with initial void ratio, natural water content, and liquid limit of clay. Furthermore, variations of Cá/Cc and cv with plasticity, and Ck with initial void ratio are presented. The differences of the methods in determining parameters are also compared and discussed. The research results provide a helpful guide to select test procedure and parameters for consolidation and settlementanalysis of clay.
