落錐試驗用於測定細顆粒土壤性質之研究

A Study of Determining Properties of Fine-grained Soil by Fall Cone Test

李欣穎(Shin-Ying Li)

指導教授 ： 馮道偉

中原大學/工學院/土木工程研究所/碩士(2004年)

https://doi.org/10.6840/cycu200400296

摘要

摘要

細顆粒土壤的指數性質需進行多項試驗方可得知，因此本研究發展以落錐試驗所求得之流線斜率m與傳統指數性質之間的關係，來表示土壤的指數性質。此外，土壤中的礦物種類可利用X光繞射分析來判定，本研究探討藉由流線斜率m來研判土壤礦物種類。
本研究進行基本物理性質試驗、落錐試驗、實驗室十字片剪試驗、無圍壓縮試驗和X光繞射試驗，以測定細顆粒土壤之指數性質、強度及礦物種類，並探討其關聯性，進而定義出新的指數關係。
根據試驗結果顯示，以落錐試驗流線斜率m來表示土壤之指數性質時，在液性限度與縮性限度有較佳結果。土壤於塑性限度之不排水剪力強度為於液性限度的22至79倍，利用阿太堡限度試驗所得液性限度及塑性限度，反推出之液性限度與塑性限度的貫入深度為20mm及2mm。以落錐貫入深度來推估不排水剪力強度時，須考慮落錐因子k值隨含水量之變化。此外，落錐流線斜率m值大於0.3時，代表土壤可能含有蒙脫土等活性較大之黏土礦物。

關鍵字

落錐試驗 ； 細顆粒土壤

並列摘要

ABSTRACT

Having to make a lot of experiments to define the index properties of fine-grained soil, relations between the fall cone flow line slope m and traditional index properties are developed in this paper. In addition, X-Ray diffraction can be used to define the type of mineral in soil. This study investigates the use of m value to determine the type of mineral in soil.
Using basic physical property tests, fall cone test, laboratory vane shear test, unconfined compressive test, and X-Ray diffraction test, the index properties, strength and type of mineral are determined in this study. Their interrelations are evaluated.
According to the test results, using fall cone test’s slope of flow line m to define the liquid limit and the shrinkage limit have the best result. The undrained shear strength at the plastic limit of soils is 22 to 79 times the undrained shear strength at the liquid limit. Evaluated from the Atterberg limits test’s liquid limit and plastic limit, liquid limit’s penetration depth is 20 mm and plastic limit’s penetration depth is 2 mm. If the penetration depth is used to estimate su, the influence of cone factor k versus water content relation should be considered. In addition, when the m value is larger than 0.3, it means that the soil may contain high activity clay minerals such as montmorillonite.

並列關鍵字

fall cone test ； fine-grained soil

參考文獻

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