^{Wang Weize， Zhang Chong， Jiang Chengshuai， Xu Yi， Zhang Xiuzhi}

School of Materials Science and Engineering， University of Jinan， Jinan 250022， China

Abstract

Objective This study investigates the effects of fundamental mix proportion parameters， including the mass ratio of binder to standard sand （binder-sand ratio）， the mass ratio of water to binder （water-binder ratio）， and the mass fraction of Portland cement Type Ⅰ （P·Ⅰ） replaced by sulphoaluminate cement （SAC） （dosage of SAC）， on the workability and mechanical properties of cement mortar with low water-binder ratio. The effects of mineral admixtures silica fume （SF） and slag （SL）， as well as admixtures nano-silica （nano-SiO₂， NS） and magnesium aluminum spinel powder （MAS） on the workability， mechanical properties， and durability of cement mortar with low water-binder ratio are analyzed. On this basis， cement mortar with low water-binder ratio that shows excellent comprehensive performance is prepared.

Methods Three influencing factors， namely the binder-sand ratio， water-binder ratio， and dosage of SAC， were selected. A three-factor， three-level orthogonal experimental method was adopted to determine the optimal combination of binder-sand ratio， water-binder ratio， and dosage of SAC. The effects of the mineral admixtures SF and SL on the workability， mechanical properties， and phase composition of cement mortar with low water-binder ratio were investigated. The effects of the dosages of admixtures NS and MAS on the workability， mechanical properties， and durability of cement mortar were analyzed.

Results and Discussion Under the condition that the total mass of four types of cementitious materials and standard sand was 2 kg， the mass fraction of PCE was 1%， and the curing age was 28 d， the cement mortar exhibited a flexural strength of 18.2 MPa， a compressive strength of 96.6 MPa， and an initial fluidity of 322 mm at a binder-sand ratio of 1.0， a water-binder ratio of 0.18， and an SAC c of 5%. When the mass fractions of incorporated SF and SL were 5% and 15%， respectively， the initial setting time and final setting time of the cement mortar specimens were 75.2 min and 108.9 min， the initial fluidity and time-dependent fluidity were 312 mm and 298 mm， and the compressive strength and flexural strength were 101.5 MPa and 22.1 MPa. When the mass fraction of NS was 0.3%， the corresponding fluidity values were 295 mm and 272 mm， the initial and final setting times were 62 min and 99 min， showing favorable workability， and the specimens achieved the optimal mechanical properties with compressive strengths of 13.7 MPa， 19.7 MPa， and 23.5 MPa， and flexural strengths of 62.6 MPa， 85.8 MPa， and 108.1 MPa at the curing ages of 1 d， 3 d， and 28 d， respectively，while the electric flux was 384 C， which satisfied the durability requirement and endowed the mortar with the best comprehensive performance.

Conclusion The water-binder ratio exerts the most significant effect on fluidity and flexural strength， while the binder-sand ratio has the greatest influence on compressive strength. Appropriate incorporation of SF and SL can improve the mechanical properties of cement mortar， and reasonable addition of NS can enhance its durability.

Keywords： cement mortar； water-binder ratio； binder-sand ratio；sulphoaluminate cement； mineral admixture； admixture

Get Citation:Wang Weize， Zhang Chong， Jiang Chengshuai， et al. Mix proportion optimization and performance regulation of cement mortar with low water-binder ratio［J］. China Powder Science and Technology， 2026， 32（5）： 1-12.

Received： 2026-03-19， Revised： 2026-05-06， Online： 2026-06-16。

Funding： The research was supported by the National Natural Science Foundation of China (Grant No. 52178211)

DOI：10.13732/j.issn.1008-5548.2026.05.008

CLC No.：TU528.2； TB44

Type Code：A

Serial No.：1008-5548（2026）05-0001-12