This paper aims to use the waste cooking oil emulsions as shrinkage reducing admixture (SRA) to improve the durability of concrete, thus the recycling of the waste cooking oil is achieved. In order to make oils emulsions SRA (OSRA) capable of reducing shrinkage and enhance its dispersion and stability, oil-in-water emulsion was prepared by dispersing the waste cooking oil in water with the help of high efficiency mixed surfactants. The effects of different contents of OSRA on the autogenous and drying shrinkage and the compressive strength of the concrete were investigated. The addition of OSRA in concrete shows a significant reduction effect on shrinkage, especially in autogenous shrinkage. Moreover, the compressive strength of concrete is enhanced with OSRA incorporated, although a slight decrease is presented with increasing OSRA content. In addition, various characterization techniques such as MIP and SEM were utilized to discuss the effect of OSRA. The results indicate that the addition of OSRA reduced the total porosity and refined the pore size by reducing significantly Ca(OH)₂ crystals, which may relate to the saponification reaction between OSRA and Ca(OH)₂. This study provides new insights into the application of the waste cooking oil in concrete and a new way to alleviate the environmental pollution and health hazard caused by waste cooking oil.

本文旨在通过将废食用油乳液用作减缩剂（SRA）来提高混凝土的耐久性，从而实现废食用油的循环利用。为了使油性乳液SRA（OSRA）能够减少收缩并增强其分散性和稳定性，通过在高效混合表面活性剂的帮助下将废弃的食用油分散在水中来制备水包油型乳液。研究了不同含量的OSRA对混凝土自生和干缩以及抗压强度的影响。在混凝土中添加OSRA显示出对收缩的显着降低作用，尤其是自发收缩。此外，掺入OSRA可以提高混凝土的抗压强度，尽管随着OSRA含量的增加，混凝土的抗压强度会略有下降。此外，利用各种表征技术（例如MIP和SEM）来讨论OSRA的效果。结果表明，OSRA的添加通过显着降低Ca（OH）降低了总孔隙率并细化了孔径_2个晶体，可能与OSRA和Ca（OH）₂之间的皂化反应有关。这项研究为废弃食用油在混凝土中的应用提供了新的见识，并为减轻由废弃食用油引起的环境污染和健康危害提供了新途径。