Book Description

Segregation of hot mix asphalt is a recurring problem in the paving industry. There is little documented research that quantifies the effect of segregation on mix properties and pavement performance. Many state highway agencies are embracing performance based quality control/quality assurance (QC/QA) programs but only a few states have performed studies to quantify the effect of segregation on pavement performance. This study was conducted on four newly constructed pavements which had noticeable spots of segregation. Cores were obtained from both segregated and non-segregated sections of the four pavements. The unit weights of the pavements were determined using a thin-lift nuclear gauge. The change in gradation on the 4.75 mm sieve was compared with asphalt content, nuclear gauge unit weight, core unit weight, and macro texture to determine if an indicator test could quantify segregation. The cores were tested for moisture sensitivity, fatigue life, and indirect tensile strength to determine the effect of segregation on performance.