Effect of Pre-wetting Lightweight Aggregates on the Mechanical Performances and Microstructure of Cement Pastes

Ding, Qingjun; Xiang, Weiheng; Zhang, Gaozhan; Hu, Cheng

doi:10.1007/s11595-020-2237-1

Cited by 12 publications

(2 citation statements)

References 23 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…For high-strength large-volume marine concrete exceeding C50, a higher binder content and lower water-cement ratio are required. C50 concrete also involves the use of ultrafine mineral admixtures such as silica fume to meet the mechanical performance requirements [20] and achieve a denser pore structure, resulting in excellent resistance to chloride salt erosion. However, the higher binder content and lower water-cement ratio lead to increased hydration heat and significant shrinkage, making the concrete prone to cracking.…”

Section: Research and Applications Of Large-volume Marine Concretementioning

confidence: 99%

The Application of Heat-Shrinkable Fibers and Internal Curing Aggregates in the Field of Crack Resistance of High-Strength Marine Structural Mass Concrete: A Review and Prospects

Li,

Yu,

et al. 2023

Polymers

Self Cite

View full text Add to dashboard Cite

High-strength large-volume marine concrete is a critical material required for the construction of large-span sea-crossing bridges. However, the widespread issue of cracking in this concrete type significantly impacts the durability and load-bearing capacity of concrete structures. Dealing with these cracks not only delays construction schedules but also increases project costs. Addressing these pressing technical issues, this project proposes the use of newly developed high-modulus heat-shrinkable fibers (polyethylene terephthalate fiber, also known as PET fiber) from the textile industry. These fibers utilize the heat generated during the hydration of large-volume concrete to trigger its contraction, applying three-dimensional micro-prestressing stress to enhance its crack resistance, while simultaneously incorporating prewetted aggregates with high-performance micro-porous structures and utilizing their internal curing effect to reduce concrete shrinkage. This helps to minimize the loss of micro-prestressing stress caused by concrete shrinkage and creep. This synergistic approach aims to improve the crack resistance of high-strength large-volume marine concrete. By employing modern testing and simulation analysis techniques, this study aims to uncover the mechanism by which the heat-shrinkable fibers exert micro-prestressing stress on concrete and the water release mechanism of internal curing aggregates during the temperature rise and fall stages of large-volume concrete. It seeks to elucidate the cooperative regulation of the microstructure and performance enhancement mechanisms of high-strength large-volume marine concrete by the heat-shrinkable fibers and internal curing aggregates. This research will lead to the development of novel methods for the design and crack control of high-strength large-volume marine concrete, which will be validated through engineering demonstrations. The outcomes of this study will provide theoretical foundations and technical support for the preparation of the crack-resistant large-volume marine concrete used in large-span bridges.

show abstract

Section: Research and Applications Of Large-volume Marine Concretementioning

confidence: 99%

The Application of Heat-Shrinkable Fibers and Internal Curing Aggregates in the Field of Crack Resistance of High-Strength Marine Structural Mass Concrete: A Review and Prospects

Li,

Yu,

et al. 2023

Polymers

Self Cite

View full text Add to dashboard Cite

show abstract

“…Ultra-High Performance Concrete (UHPC), also known as Reactive Powder Concrete (RPC), is the most innovative cementitious engineering material of the past three decades [5][6][7][8], compatible with the first patent filed by Hans Henrik Bache of Denmark in 1979 and his establishment of the DSP theory [9][10][11][12]. The addition of different aggregates and admixtures will affect the performance of UHPC [13][14][15][16]. Impact-and abrasionresistant UHPC provides new ideas for bridge piers and columns in western mountainous areas.…”

Section: Introductionmentioning

confidence: 99%

The Influence of Curing System on the Macroscopic Performance and Microstructure of Anti-Abrasive UHPC

Li,

Yu,

et al. 2023

Coatings

Self Cite

View full text Add to dashboard Cite

In a previous study, we utilized saturated prewet high titanium heavy slag sand to produce UHPC (ST-UHPC). ST-UHPC has high impact and abrasion resistance. For better ST-UHPC applications, we investigate the mechanism of ST-UHPC under different curing systems from the microstructure and macroscopic perspective in this paper. We prepared ST-UHPC under four maintenance conditions: 20 °C standard curing, 90 °C steam curing, 90 °C dry curing and 210 °C 2 MPa pressure steam curing. Then, we analyzed the hydration product composition, the degree of cement hydration, the C-A-S-H gel microstructure and the substitution of Al3+ for Si4+ in relation to these prepared ST-UHPCs. Compared with standard curing, dry curing at 90 °C accelerated the water evaporation and reduced the hydration degree of ST-UHPC cementite. However, pressure steam curing significantly improved the hydration degree of ST-UHPC cementing material, and increased the MCL and Al[4]/Si of C-A-S-H gel. In addition, pressure steam curing reduced the Ca/Si and promoted the conversion of C-A-S-H cementing to tobermorite. Compared with dry curing at 90 °C, pressure steam curing significantly improved the macroscopic properties of ST-UHPC. The macro-performance difference of ST-UHPC under standard curing and 90 °C steam curing is small. The reason is that steam curing caused the water to be rapidly released in the internal aggregate of ST-UHPC. This resulted in the increase of the interface between the internal aggregate of ST-UHPC and the ST-UHPC cementate. The harmful pores in the ST-UHPC matrix under steam curing were also increased. To sum up, compared with standard curing, dry curing at 90 °C weakened the mechanical properties and microstructure of ST-UHPC, but steam pressure curing increased them. The single steam curing had no significant effect on the mechanical properties and microstructure of the ST-UHPC. Therefore, non-steam and room-temperature moisturizing maintenance should be adopted for anti-abrasive UHPC.

show abstract

Effects of Different Calcining Temperatures on the Properties of Ceramsite Prepared by High-carbon Gasification Slag

et al. 2023

J. Wuhan Univ. Technol.-Mat. Sci. Edit.

View full text Add to dashboard Cite

Effect of Pre-wetting Lightweight Aggregates on the Mechanical Performances and Microstructure of Cement Pastes

Cited by 12 publications

References 23 publications

The Application of Heat-Shrinkable Fibers and Internal Curing Aggregates in the Field of Crack Resistance of High-Strength Marine Structural Mass Concrete: A Review and Prospects

The Application of Heat-Shrinkable Fibers and Internal Curing Aggregates in the Field of Crack Resistance of High-Strength Marine Structural Mass Concrete: A Review and Prospects

The Influence of Curing System on the Macroscopic Performance and Microstructure of Anti-Abrasive UHPC

Effects of Different Calcining Temperatures on the Properties of Ceramsite Prepared by High-carbon Gasification Slag

Contact Info

Product

Resources

About