Subsurface drainage systems

Abstract

Subsurface drainage is a key element in the design of pavement systems. Indiscriminate exclusion of this element will assuredly lead to the premature failure of pavement systems, thereby resulting in high life-cycle costs. Faulting and associated pumping in rigid pavements systems, extensive cracking from loss of subgrade support in flexible pavements, and distress from frost heave are clear signs of inadequate drainage. The two basic design strategies promoted are to (1) prevent water from entering in the first place and (2) quickly remove any water that does infiltrate. After years of unsuccessful sealing attempts, the profession has learned that we cannot prevent water from entering a pavement and that removal of water is essential for the pavement elements to perform as desired (Christopher and McGuffey 1997).