PORE PRESSURE & SETTLEMENT BEHAVIOUR OF SOFT CLAY OF INDONESIA AND MALAYSIA UNDER EMBANKMENT LOADING

• Main Author: Padmantazil, Adyawati
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/7049
• Institution: Institut Teknologi Bandung

ABSTRACT: <br /> <br /> <br /> The pore pressure dissipation and consolidation settlement characteristics of an Indonesian and a Malaysian marine soft clay have been examined. Field values were compared with those analysed using KON-2D-JR, a specially devised computer program to calculate two-dimensionally, using classical consolidation theory, the pore pressure dissipation behaviour and all aspects of settlement of soft compressible deposits. The program has been discussed in earlier studies. Comparison was also made with the behaviour of Bandung soft freshwater clay, which has been analysed in some detail previously. <br /> <br /> <br /> It was confirmed that both the Indonesian deposits exhibit very fast rates of drainage, several order of magnitude larger than indicated from conventional site investigation and laboratory practice. Once the correct layer consolidation parameters were used, reasonable back-analysed dissipation and settlement characteristics in line with field behaviour were found. In addition, there was reasonable compatibility between values of <br /> <br /> <br /> coefficients of consolidation to satisfy both requirements. <br /> <br /> <br /> Very careful site investigation and laboratory testing had been carried out on the Malaysian deposit. The parameters derived therefrom were found to provide fairly reasonable pore pressure dissipation characteristics in computer analysis compared with field observations, greater differences being found at locations remote from the centreline of embankment loading. However, a significantly higher value of coefficient of consolidation was required when matching analysed and field settlement behaviour. This has been attributed to destructuration. <br /> <br /> <br /> While earlier studies had indicated that a value of unity could be taken for Skemptons parameter A for soft soils, and this was found reasonable for the Indonesian clays, lower values were found to be required for the Malaysian clay, particularly during the loading phase. The parameter, which reflects past stress behaviour, requires further examination, beyond the scope of this study.