Performance of Mortar Based on Phosphogypsum-Based Fine Lightweight Aggregate

doi:10.16552/j.cnki.issn1001-1625.2024.1299

Abstract

Abstract: The preparation of phosphogypsum-based fine lightweight aggregate (PG-LWA) by using activator, slag powder and phosphogypsum (PG) is one of the effective ways to recycle PG. In this paper, the preparation method of PG-LWA was introduced, and the quality of PG-LWA was evaluated from the aspects of physical properties, strength and microstructure. PG-LWA was used to prepare cement mortar, and the expansion, setting time and mechanical properties of mortar samples were tested. The results show that during the preparation of PG-LWA, the raw materials undergo alkali activation reaction to form hydrated calcium silicate (C-S-H) and ettringite (AFt). When the mass fraction of PG is 70%, the fineness modulus of the prepared PG-LWA is 4.4, the cylinder compressive strength at over dry is 4.65 MPa, and the porosity is 37.29%. When the water-binder ratio is 0.5 and the mass fraction of PG is 70%, the expansion degree of cement mortar prepared by replacing sand with PG-LWA is 213 mm, the final setting time is 300 min, and the 28 d compressive strength is 22.1 MPa.

Key words: phosphogypsum, artificial aggregate, mortar, mechanical property, microstructure

CLC Number:

TU528

REN Jun, YU Yongkun, MAO Wenting, ZHANG Yu, WANG Dafu. Performance of Mortar Based on Phosphogypsum-Based Fine Lightweight Aggregate[J]. BULLETIN OF THE CHINESE CERAMIC SOCIETY, 2025, 44(4): 1420-1427.

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