Semi firm long lasting. Application to the Spanish case

David HERNANDO ARROBA
Department of Civil Engineering. Transport and Territory
Polytechnic University of Madrid (28040 Madrid)

Miguel Angel DEL VAL Melus
Department of Civil Engineering. Transport and Territory
Polytechnic University of Madrid (28040 Madrid) 

ABSTRACT:

The appearance of deterioration requires undertake periodic renovations that increase the overall cost of the sections firm, so a good understanding of the mechanisms of deterioration is essential to prolong shelf life and reduce costs. In the case of the firm semirigid they have been identified as major mechanisms of deterioration in the short and medium term structural fatigue of cement treated layers, plastic deformations of the asphalt pavement, the downward cracking, shrinkage cracking, reflection crack and thermal fatigue. The analysis of the semi-rigid sections contained in the Spanish standard 6.1 IC (2003) shows that only four of the proposed sections meet the structural conditions necessary to be regarded as long-term firm, although two of them are clearly overstated. However, it is possible to optimize the design of these sections by reducing the thickness of the asphalt pavement and incorporating antireflection fissure system. Thus this paper proposes, for the Spanish case, the characteristics that should have the layers that make up a semi-firm to avoid the appearance of significant deterioration in its structural elements over a period of 30 years clearly superior to life.

KEYWORDS: 

Pavement, semi-rigid Firm, Life, Long-term impairment, behavior.