City Research Online

Remoulding of the Mercia Mudstone Group around CFA pile shafts

Seward, L. J., Stallebrass, S. E. and Skipper, J. (2013). Remoulding of the Mercia Mudstone Group around CFA pile shafts. Quarterly Journal of Engineering Geology and Hydrogeology, 46(1), pp. 41-51. doi: 10.1144/qjegh2011-053


A field test has been undertaken to investigate changes to in situ Mercia Mudstone at the pile soil interface after installation of four 5.5 m long 350 mm diameter CFA piles. The test investigated whether a remoulded zone exists, the extent of the zone, changes caused by remoulding and the effect of the installation method. The piles and surrounding soil were excavated after installation to a depth of just under 2 m. The sections of pile and surrounding soil were returned to the laboratory where a variety of detailed observations at both micro and macroscopic scales were undertaken, together with chemical and mineralogical analysis. It was found that a remoulded zone existed in all piles but that this varied in thickness both laterally and vertically around a pile. Across all piles the maximum thickness observed was 55 mm. The average thickness, fabric and texture were all affected by installation method. A distinctive vertically orientated fabric was observed in which up to four vertically orientated layers could be distinguished. There was evidence of changes in texture/fabric, structure, colour, mineralogy and chemistry.

Publication Type: Article
Subjects: T Technology > TA Engineering (General). Civil engineering (General)
Departments: School of Mathematics, Computer Science & Engineering > Engineering
Download (1MB) | Preview



Downloads per month over past year

View more statistics

Actions (login required)

Admin Login Admin Login