Evaluation of RAP Engineering Characteristics in Layered Soil

Document Type : Regular Paper


1 Assistant Professor, Al Musaib Technical College‎,‎ Al-Furat Al-Awsat Technical University, Kufa, Iraq

2 Assistant Lecturer, Al Musaib Technical College‎,‎ Al-Furat Al-Awsat Technical University, Kufa, Iraq


The current investigation used 16 model tests with two alternative foundation shapes, one strip and the other square, for a total of eight model tests for each foundation type. A model test was conducted only on natural soils to evaluate the two types of foundation and both circumstances of improvement utilizing RAP. The model square footing was laid on a layer of (RAP), with the varied widths (1.25B and 1.75B) and different thicknesses (0.25 B, 0.50 B, and 0.75 B in which B=footing width). Six model tests are tested in two widths (1.25B and 2.50B) in model strip footing treated (RAP), and three thicknesses (0.50B, 1B, and 1.5B) in each width are done. ‎The settlement improvement factor was utilized to show the (RAP) layer's influence. The data suggested that the (RAP) layer beneath the foundations influenced settlement significantly.‎ The RAP material in a square footing with a depth of 0.75 B offered the most efficient settlement reduction, with the lowest settlement improvement factor of all model tests. ‎ A model test was run with a RAP width of B and a depth of 0.25 B. It was discovered that RAP soil treatment reduced settlement by 0.34, implying that treated soil settled by 34% less than untreated soil. 


Main Subjects

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  • Receive Date: 12 August 2021
  • Revise Date: 07 September 2021
  • Accept Date: 13 September 2021
  • First Publish Date: 13 September 2021