Appraisal of soil-cement columns load displacement behavior through full-scale tests database

Abstract

Soil-cement columns are implemented in coastal areas to improve the capacity of loose, soft, and dredged soils, reduce settlement, and mitigate liquefaction effects. Static load testing is used for quality control and the verification of design assumptions. Given the greater reliability of full-scale testing results compared to physical and numerical modeling results and the lack of a database for soil-cement columns, 42 full-scale loading records on these columns were compiled to assess the behavior of these columns and identify the most influential factor in their behavior. The database contains columns ranging in length from 5 to 19 meters with diameters ranging from 40 to 120 cm, as well as soil profiles ranging from clay to sand and mixed soil. Their behavior was evaluated using a hyperbolic relationship. The results indicate that component materials, influenced by implementation technique, in-situ soil properties, and reinforcing, more significantly influence the behavior of columns than the columns’ length. The columns are categorized into three separate groups, which are separated due to their different equivalent unconfined compressive strengths and shapes. These categories allow for the prediction of the load-displacement ratio diagram range of the column based on initial information such as the column diameter, length, and properties of in-situ soil. The upper and lower bounds of categories were validated by the loading results of five soil-cement columns implemented in Iran coastal line.