Influencing factors and long-term mechanical property test of ultra-high performance concrete (UHPC) with microvoids optimization
Year: 2023
Type: preprint
Abstract: UHPC is the most potential matirals in deep underground constructions due to its remarkable strength and durability. This paper investigated the effects of different water-cement ratios, active material dosages, polymer admixtures, curing conditions and polymer fiber materials on the physical and mechanical properties of ultra-high performance concrete (UHPC). It was found that the optimal binder-aggregate ratio of UHPC was 45:55. UHPC mixed with silica fume exhibited higher strength and volume shrinkage rate than that mixed with blast furnace slag and fly ash with polycarboxylate superplasticizer adding. The addition of superabsorbent polymers shrinkage reducing agent(CS) could improve UHPC fluidity to a certain extent, but when the dosage exceeded 3\%, the surface displayed certain spalling, with strength reduced from 170.1 to 134.1MPa. Hence, CS dosage is recommended to be controlled within 3\%. Curing at 90$^\circ$C can not only shorten the curing time, but also improve the strength. Two types of fibers was investigated in this paper. The result showed that addition of polyvinyl alcohol fiber (PVA) was optimal for the performance optimization of UHPC than alkali resistant glass fibre(AR-GF). Additionally, the creep performance test showed that the long-term creep strength under multistage loading was about 212MPa, and the long-term creep deformation greatly affected the stability of UHPC structure.
Source: Research Square
Authors: Wei Yin, Kun Zhang, Peng Huang, Xi Chen, Lei Zhou
Institutions: Huai'an University, China University of Mining and Technology
Language: English
Subfield: Civil and Structural Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W4386615441