Strength mechanism and improvement methods of cement bitumen emulsion mixture

Author(s): Jian Ouyang, Wen Xu, and Lijun Hu
Paper category: Proceedings
Book title: Proceedings of the International Conference on Sustainable Materials, Systems and Structures (SMSS2019) New Generation of Construction Materials
Editor(s): Marijana Serdar, Nina Štirmer, John Provis
ISBN: 978-2-35158-217-6,
Vol 1. ISBN: 978-2-35158-223-7
e-ISBN: 978-2-35158-218-3
Publisher: RILEM Publications SARL
Publication year: 2019
Pages: 100-107
Total Pages: 8
Language : English

Abstract: To increase the strength of CBEM, the voids content, strength and microstructure of CBEM were firstly studied to find the deficiency of CBEM, and then methods were proposed to overcome the deficiency of CBEM. Results indicates that CBEM at the maximum strength has much lower water content than that at the minimum voids content. This is because the strength of CBEM is not only dependent on the voids content of CBEM, but also it is related to the microstructure of cement bitumen emulsion (CBE) paste and the interface between CBE paste and aggregate. Low water content can help to form a dense microstructure of CBE paste, which is beneficial to the strength of CBEM. However, CBE paste has a poor bonding interface with aggregate at low water content. The addition of superplasticizer and wetting agent (JFC, a fatty alcohol–polyoxyethylene ether) can efficiently improve the bonding interface between CBE paste and aggregate and greatly increase the strength of CBEM. The failure face of CBEM can be changed from “adhesive failure” to “cohesive failure” and “fine aggregate fracture” when superplasticizer and JFC are added. The maximum indirect tensile strength can increase by 21.5% and 29.1% for CBEM with superplasticizer and CBEM with superplasticizer and JFC, respectively.

Online publication : 2019
Publication type : full_text
Public price (Euros) : 0.00