01154600

Component

This paper presents NCDOT’s general guidance and practice of degradable rock use in highway embankment construction and case studies of four highway projects in which degradable rock related embankment and/or pavement failures occurred. Despite potential construction and maintenance problems, degradable rocks have been used in many highway construction projects located in the Deep River Triassic Basin geologic province of North Carolina to reduce earthwork cost, and this practice will continue. It has been noted in recent years that degradable rock related embankment and/or pavement failures have occurred more frequently than previous years. Rainfall pattern change, improper quality control/assurance, more construction activities, and scarcer material resources are possible reasons for this observation, though no definite answer can be given. Even with a substantial amount of failure investigation work, negative effects of degradable rock on the performance of embankment and pavement are sometimes difficult to evaluate or quantify because many other factors could contribute to the failures. NCDOT’s handling of degradable rock in highway projects has been generally successful with some exceptions; however, the current practice needs to be improved to reduce such failures. Suggested improvements in the NCDOT’s current practice are discussed.

01147878

10-2424

English

11p

2010

Transportation Research Board 89th Annual Meeting

DVD

Figures (2) ; References (3)

Case studies; Construction management; Cracking; Embankments; Properties of materials; Sedimentary rocks; Slaking; Testing; Weak rock

North Carolina Department of Transportation

Geotechnology; Highways; I24: Design of Bridges and Retaining Walls

Transportation Research Board Annual Meeting 2010 Paper #10-2424

BTRIS, TRIS, TRB

Jan 25 2010 11:08AM