Document Type

Article

Abstract

This paper describes an evaluation of the mechanical performance of fly ash stabilized materials. Soft clay soil, asphaltic recycled pavement material (RPM), and road-surface gravel (RSG) were stabilized using Class C and off-specification fly ashes to create working platforms or stabilized base courses for construction of flexible and rigid pavements at six sites in Wisconsin and Minnesota. California bearing ratio (CBR), resilient modulus (Mr) tests, and unconfined compression (qu) tests were conducted on the subgrade soil, RPM, and RSG alone and on mixtures prepared in the field and the laboratory to evaluate improvements in bearing resistance and stiffness. Fly ash stabilization improved the stiffness and strength of the materials significantly. After 7 d of curing, CBR of the stabilized materials (10 to 150) was two to ten times the CBR of the materials alone (1 to 50). The Mr of the stabilized materials ranged between 20–200 MPa after 14 d of curing, whereas the Mr of the materials alone was 10,120 MPa. The qu of the unstabilized subgrade is in average of 121 kPa and the field-mix fly ash stabilized materials have qu between 254 kPa and 368 kPa (mean 5 311 kPa). Lower CBR, Mr and qu were obtained for stabilized materials mixed in the field relative to the stabilized materials mixed in the laboratory (64% lower for CBR, 25% lower for Mr, and 43% lower for qu).

First Page

43

Last Page

49

DOI

10.4177/CCGP-D-09-00018.1

Volume

1

Publication Date

1-1-2010

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