详情

原文传递 HOT-MIX ASPHALT LAYER THICKNESS DESIGN FOR LONGER-LIFE BITUMINOUS PAVEMENTS.

题名：	HOT-MIX ASPHALT LAYER THICKNESS DESIGN FOR LONGER-LIFE BITUMINOUS PAVEMENTS.
作者：	Von-Quintus-HL
关键词：	Asphalt-pavements; Deflection-; Durability-; Equivalent-single-axle-loads; Fatigue-Mechanics; Hot-mix-asphalt; Long-Term-Pavement-Performance-Program; Modulus-of-elasticity; Pavement-cracking; Pavement-design; Pavement-layers; Pavement-performance; Properties-of-materials; Roughness-; Rutting-; Seasonal-variations; Service-life; Thickness-
摘要：	The performance of a hot-mix asphalt (HMA) pavement structure is dependent on the interaction between pavement responses and the strength and modulus of the different layers. Wheel loads induce stresses and strains in each layer, which can result in damage of bound and unbound materials. The accumulation of damage within the pavement layers eventually becomes visible at the surface of the pavement in the form of rutting, cracking, and surface roughness. Structural deterioration is normally associated with cracking and rutting. These two distresses, along with the cumulative or incremental damage concept, historically have been used in determining the layer thickness requirements needed to resist structurally related distresses. An overview is presented of a procedure that has been used to design long-life HMA pavement structures for heavily traveled roadways. The design procedure is based on limiting the tensile strain at the bottom of the HMA layer and the vertical compressive strain at the top of the subgrade or embankment soil. Long life is defined in this paper as 40+ years without any major structural failures throughout the HMA layer. The design traffic used in previous design studies has exceeded 40 million equivalent single-axle loads. The methodology applies the cumulative damage concept in the prediction of fatigue (load-related cracking) and subgrade distortion. Seasonal and other variations in material properties, including the modulus of the HMA layer, are considered in the procedure by use of the "equivalent modulus" concept. In other words, the incremental damage computed in the HMA layer for a specific modulus would be equal to the summation of the incremental damage computed allowing the modulus of the HMA layer to change with the season. Two other criteria are used for the mechanistic-empirical thickness design checks. One is based on limiting the maximum surface deflection under the design load and the other is based on limiting the modulus ratio between two adjacent unbound pavement layers. With this methodology, three key issues related to fatigue cracking in HMA layers are addressed. The first issue is the reality of the concept of an "endurance limit" for the layer thickness design of HMA layers. The second issue is the location of where load-related cracks initiate in the HMA layer (at the bottom of the layer versus the top of the layer), and the third issue is confirmation of the fatigue characteristics of HMA layers for use in layer thickness design. Some of the Long-Term Pavement Performance data, both materials and distress data, are used to support the criteria employed in the design procedure and the methodology of that procedure.
总页数：	Transportation Research Circular. 2001/12. (503) pp66-78 (4 Fig., 14 Ref.)
报告类型：	科技报告