Evaluation of a Cold-Mixed High-Performance Polyurethane Mixture

Abstract

The energy consumption and greenhouse gas emission of asphalt pavement have become a very serious global problem. The high-temperature stability and durability of polyurethane (PU) are very good. It is studied as an alternative binder for asphalt recently. However, the strength-forming mechanism and the mixture structure of the PU mixture are different from the asphalt mixture. This work explored the design and performance evaluation of the PU mixture. The PU content of mixtures was determined by the creep slope (K), tensile strength ratios (TSR), immersion Cantabro loss (ICL), and the volume of air voids (VV) to ensure better water stability. The high- and low-temperature stability, water stability, dynamic mechanical property, and sustainability of the PU mixture were evaluated and compared with those of the stone matrix asphalt mixture (SMA). The test results showed that the dynamic stability and bending strain of the PU mixture were about 7.5 and 2.3 times of SMA. The adhesion level of PU and the basalt aggregate was one level greater than the limestone, and basalt aggregates were proposed to use in the PU mixture to improve water stability. Although the initial TSR and ICL of PU mixture were lower, the long-term values were higher; the PUM had better long-term water damage resistance. The dynamic modulus and phase angles (φ) of the PU mixture were much higher. The energy consumption and CO2 emission of the PU mixture were lower than those of SMA. Therefore, the cold-mixed PU mixture is a sustainable material with excellent performance and can be used as a substitute for asphalt mixture.

Interlaminar Shear Characteristics, Energy Consumption, and Carbon Emissions of Polyurethane Mixtures

“…Further, asphalt pavement is prone to rutting, looseness, and other issues [1,2]. To solve the aforementioned problems, high molecular polymers polyurethane (PU) is used as binder, the PU mixture pavement is intended to replace asphalt pavement [3]. The entire construction process of PU mixture production, transportation, and compaction is conducted at room temperature, which greatly reduces the consumption of energy consumption and carbon emissions.…”

Mechanism of Polyurethane Binder Curing Reaction and Evaluation of Polyurethane Mixture Properties

“…To mitigate these problems, scholars have proposed the concept of polyurethane (PU) mixture pavement, where high molecular weight polymer PU is used to replace asphalt as the binder for pavements [5]. Since the end of the 1970s, researchers have begun to use one-or two-component PU to replace asphalt as the binder for functional pavement [6][7][8][9][10][11][12][13][14][15][16][17][18][19][20][21][22][23], pavement structural layers [24][25][26], bridge deck pavement [27], etc.…”