ABSTRACT:

Water content in fine-grained sedimentary rocks is an important consideration in many engineering projects. It has been well establish that water content of these rocks can significantly changes most aspects of physical and mechanical properties. This paper presents the effect of water content on the mechanical behavior of three different types of fine-grained sedimentary rocks, clayshale, mudshale and mudstone from different locations. Many samples were tested at a wide range of water contents varying from oven-dried to saturated condition. A general equation was developed for this type of fine-grained sedimentary rocks that may be used for predicting uniaxial compressive strength from the available information on water content.

INTRODUCTION

Fine-grained sedimentary rock in this study includes mudrock or shale. This type of rock is formed in both marine and nonmarine environments and it is one of the most abundant sedimentary rocks. Tucker (1991) reported that mudrock is the most abundant of all lithologies, constituting some 45–55% of sedimentary rock sequences. Because of its abundance, mudrock is the most frequently encountered rock type in engineering construction. King et al. (1994) reported that shales are found in many large civil engineering structures in United Kingdom and elsewhere. Moreover this rock is one of the most problematic materials for geotechnical and petroleum engineers. The compressive strength of this type of rocks under different water content conditions have been studied by many researchers (Van Eeckhout, 1976; Bauer, 1984; Tandanand, 1985; Steiger & Leung, 1990; Zhiyl & Jinfeng, 1993; Hsu & Nelson, 1993; Ghafoori, 1995; Lashkaripour & Ghafoori, 1999). Analysis of their results has shown that water content of these rocks significantly changes most aspects of physical and mechanical properties. Van Eeckhout (1976) studied the effect of water content on the strength of different rocks.

This content is only available via PDF.
You can access this article if you purchase or spend a download.