Laboratory performance evaluation of a cold patching asphalt material containing cooking waste oil

Every day, large amounts of cooking waste oil (CWO) are produced globally from cooking. As heavy metals and other hazardous substances are found in CWO, improper treatment of CWO could cause environmental pollution and endanger food safety. Recycling CWO as a pavement pothole repair material is an innovative, environmentally friendly and resource saving method of pavement road maintenance. In this study, cold patching asphalt (CPA), which is used to repair pavement potholes, is prepared from a simple mixture of CWO and diesel as the diluent, and the performance of this CPA is evaluated in the laboratory. To improve the adhesion of the CPA, a self-developed auxiliary additive is also used. CPA samples are prepared, and two sets of formulas are determined based on the Brookfield viscosity test results. Then, cold patching asphalt mixtures (CPAMs) containing CWO are designed and evaluated. The results show that CPA has good adhesion to aggregates (>95%) at CWO contents from 15 wt% to 35 wt% in the diluent, diluent contents from 21 wt% to 23 wt% and auxiliary additive contents of 3 wt% or 4 wt% in the asphalt. In addition, the introduction of CWO in CPAM has no discernible effect on its strength, and the cost of CPAM containing CWO is lower than or similar to that without CWO. (C) 2019 Published by Elsevier Ltd.