Dr. Binu SharmaProfessor, Civil Engineering Department, Assam Engineering College, Assam, India
Speech Title: Static Compaction Characteristics of Soils
Abstract: The modified Proctor’s test, the reduced modified Proctor's test, the standard Proctor's test and the reduced standard Proctor’s test are dynamic methods which are often used in the laboratory to ascertain the compaction characteristics of soils at different energy levels. However, these dynamic compaction methods are laborious and time consuming and have some shortcomings for which it has been attempted in recent years to ascertain the compaction characteristics of soil by static compaction method.
A laboratory procedure is devised to determine the relationships between moisture content and dry unit weight by using static compaction method for different static pressures. The static compaction pressure test is performed in the Proctor mould where the soil is statically compacted in the mould at different water contents. For fined grained soils, similar to dynamic compaction, parabolic curves were obtained between moisture content vs. dry unit weight at different static pressures. The static pressures equivalent to the energy inputs of the different Proctors test to obtain the corresponding optimum moisture content and maximum dry unit weight were determined for fine grained soils. The equivalent static pressures so determined can be used to obtain the parabolic static compaction curve which will result in simplification of the compaction procedure and will also result in considerable saving of time, money and effort. However, in case of fined grained soils, an equivalent static pressure could not be determined for the Modified Proctor test. The study is also extended to determine the static compaction characteristics of coarse grained soils also. In case of coarse grained soils, an equivalent static pressure could not be determined as that of fine grained soils. For SP class of soil, an undulatory pattern with maximum dry unit weight near dry and towards saturated condition was observed for both the static and dynamic compaction. The dynamic compaction curve for both SC and SM class of soil is parabolic in nature. For SM class of soil, static compaction curve show a wavy pattern with maximum dry unit weight at dry and near saturated condition whereas for SC class of soil only one-sided compaction part of the curve for the rising portion of the dry of optimum side was generated.
Biography: Binu Sharma is serving as professor in Civil Engineering in Assam Engineering College, Assam since 2005. She held a B.E. from Guwahati University, Assam, India, M.E. from Roorkee University. Roorkee, India and PhD from Guwahati University, Assam India. She joined as lecturer in Assam Engineering College in Assam in 1987. Her main area of research includes analysis and prediction of soil behavior, soil liquefaction, micropiles- soil structure interaction analysis, expansive soils. She has published around 55 research papers in national and international journals and conferences, and has been associated with many consultancy works through Consultancy Services: CAEC – CON, Civil Engineering Department, Assam Engineering College.
She has received the Dinesh Mohan Biannual Award for best paper in ‘Pile Foundation’ for the year 2011 - 2012 awarded by the Indian Geotechnical Society, has also received the IGS- Geotech Biannual Award for best paper in ‘Innovation in Field Exploration’ for the year 2012 - 2013 awarded by the Indian Geotechnical Society.
She has served as the Vice Chairman of Indian Geotechnical Society, Guwahati Chapter N.E., and the Chairman of Indian Geotechnical Society, Guwahati Chapter N.E. for two terms.