以分離式單向度壓密儀研究主壓密過程中之壓縮性參數

Taylor 和Merchant 於1940年提出了一個壓密組合方程式，在此方程式中，包含了二項壓縮性參數，即和。其後，有學者開始以不同的試驗方式來驗証壓密組合方程式的正確性，並且對這兩項參數在主壓密過程中的行為作初步的研究與探討。本研究的主要目的是希望藉由分離式單向度壓密儀得到主壓密過程中的壓縮性參數和，並進一步探討其相互之間可能存在的關係。國外文獻中已有少數利用分離式壓密儀進行土壤壓密行為的研究，其最大的特點在於利用串聯排水的原理來模擬較厚土層的壓密行為，並且可同時測得各個壓密儀試樣單元的軸向變位和孔隙水壓的變化。根據研究的結果顯示，以分離式單向度壓密儀對試體進行不同厚度的壓密試驗，不僅可以獲得土壤壓密組合方程式內所包含各項參數之值，並可驗證壓密組合方程式的正碓性；然而，在分析壓縮性參數於主壓密過程中的行為及其相互之間的關係部分，以本研究試驗所得的數據看來，目前尚無法找出一規律的關係。

關鍵字

壓縮性參數；壓密；壓密組合方程式；分離式單向度壓密儀

並列摘要

Since 1940, Taylor and Merchant proposed a constitutive equation of one-dimentional compression, which contains two compressibility parameters with respect to effective stress, , and with respect to time, . Several researchers have confirmed the validity of the constitutive equation using different forms of experiment. The interrelationships of compressibility parameters during primary consolidation have also been studied. The purpose of this study is to obtain the compressibility parameters and during primary consolidation by using the separated-type consolidometer. The characteristic feature of the separated-type consolidometer is to simulate the dissipation of pore pressure of the thicker layers by draining in series. The vertical displacement at the top and the pore pressure at the bottom can be measured for each consolidometer. According to the test results in this study, it is possible both to evaluate the compressibility parameters during primary consolidation and to confirm the validity of the constitutive equation by using the separated-type consolidometer with different heights of specimens. However, it is still unable to establish a general rule that describes the behavior and interrelationship of and during primary consolidation.

並列關鍵字

consolidation ； compressibility parameters ； constitutive equation of one-dimentional compres ； separated-type consolidometer

參考文獻

2. Taylor, D. W. and Merchant, W. (1940) "A theory of clay consolidation accounting for secondary compression," Jour. of Mathematics and Physics, 19 (3), pp. 167-185.

4. Vaid, Y. P., Robertson, P. K. and Campanella, R. G. (1979) " Strain rate behavior of Saint-Jean-Vianney clay," Canadian Geotechnical Jour.,16, pp. 34-42.

5. Mesri, G. and Choi, Y. K. (1979) " Strain rate behavior of Saint-Jean-Vianney clay：Discussion," Canadian Ceotechnique, Jour., 16 (4), pp. 831-834.

8. Berre, T. and Iversen, K. (1972) " Oedometer tests with different specimen heights on a clay exhibiting large secondary compression," Geotechnique, No. 22, pp. 53-70.

1. 馮道偉，民國八十一年，"天然軟弱粘土壓縮性之研究"，中興工程，第36期，第1-7頁。