Print Email Facebook Twitter The effect of sulfate-rich sewage sludge ash on the volume deformation and micorstructure of cement paste Part of: 4th International Rilem Conference on Microstructure Related Durability of Cementitious Composites· list the conference papers Title The effect of sulfate-rich sewage sludge ash on the volume deformation and micorstructure of cement paste Author Gu, Chunping (Zhejiang University of Technology, China) Ji, Yongjie (Zhejiang University of Technology, China) Yang, Yang (Zhejiang University of Technology, China) Liu, Jintao (Zhejiang University of Technology, China) Ni, Tongyuan (Zhejiang University of Technology, China) Date 2021-04-29 Abstract Sewage sludge ash (SSA) is the combustion residue of the sewage sludge obtained from wastewater treatment plants. In China, SSA normally contains high content of SO3, which may cause detrimental effect on the volume stability of cement-based materials. This study investigated the effect of sulfate-rich SSA (SR-SSA) on the volume deformation and the microstructure of cement paste. The autogenous shrinkage and drying shrinkage of cement pastes incorporating SR-SSA were tested. The microstructure of cement pastes incorporating SR-SSA was studied with mercury intrusion porosimetry (MIP) and scanning electron microscopy (SEM). The results show that the addition of SR-SSA reduced the autogenous shrinkage of cement paste, but increased the drying shrinkage of cement paste. Hence the addition of SSA may cause more serious cracking problem of cement-based materials under drying conditions, but could inhibit the cracking under sealed condition. The SEM and MIP investigations showed that, when SR-SSA was presented, more ettringite was generated in the cement paste and the porosity of the cement paste became higher. Subject microstructurecement pastesulfatesewage sludge ashshrinkage To reference this document use: http://resolver.tudelft.nl/uuid:4b10ddb7-9ad0-49c5-a4cb-df098cdebcb9 Part of collection Conference proceedings Document type conference paper Rights (c) 2021 the authors Files PDF The effect of sulfate-ric ... paste.pdf 1.42 MB Close viewer /islandora/object/uuid:4b10ddb7-9ad0-49c5-a4cb-df098cdebcb9/datastream/OBJ/view