Weathered Characteristics of Silty Mudstone in Hunan Province, China

Abstract:

To study the weathered characteristics of silty mudstone in Hunan province, china, mineral analysis, softening test, disintegrability test, and weathering rate test are used. The test results show that with the increasing of weathering degree, the content of clay minerals increase from 34.1% to 57.2%, the content of quartz decrease from 58.6% to 38.7%. The content increasing ratio of Fe₂O₃ and Al₂O₃ are 52% and 44% respectively, the content decreasing ratio of K₂O is 52%. From lightly weathered rock to completely weathered rock, the decreasing ratio of dry density is 20%, the increasing ratio of water absorption is 40%, the increasing ratio of porosity is 190% nearly and the decreasing ratio of natural compressive strength is 84%. For strongly weathered silty mudstone, the softening coefficients of the first dry-wet cycle, the second cycle and the third cycle are 30%, 54% and 72% respectively. So when silty mudstone weathered further, the content of primary minerals decrease and the content of secondary minerals increase. The weak activity chemical composition increase and the strong activity chemical composition decrease. Weathering cause the mechanical properties of rock become worse. Repeated dry-wet cycle can accelerate the softening of rock. The larger the exposure area of rock is, the quicker the rock weathered.

• Periodical: Advanced Materials Research (Volumes 1065-1069)
• Pages: 264-268
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.1065-1069.264
• Online since: December 2014
• Authors: Ji Hua Wang, Chen An*, Zhou Yi
• Keywords: Silty Mudstone, Weathered Characteristics, Weathering

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