Bonding behavior of concrete matrix and alkali-activated mortar incorporating nano-SiO2 and polyvinyl alcohol fiber: Theoretical analysis and prediction model

The prerequisite to synthesize PCE was to prepare new macromonomers with controlled molecular mass, adjustable hydrophilic-lipophilic groups, long-chain alkyl groups, and large terminal hydroxyl groups as well. Structural modifications in the molecular scale of polycarboxylate superplasticizer (PCE) would lead to changes in properties of dispersion and water retention as well as enhancement in the compatibility of Portland cement and so on. This paper reviewed recent developments from synthetic methods of macromonomers as the initial step of production of PCE, PCE at room and elevated temperatures, and relationships between structure and properties of PCE. Through the analysis of references, it was found that PCE synthesized at room temperature had the same performance with PCE synthesized at elevated temperature in terms of conversion rate and initial dispersion in cement but broader molecular weight distribution. Conclusively, the dispersion of PCE in cement might be explained by multiple theories rather than a single one based on development trends as discussed in this paper.

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Progresses in Synthesis of Polycarboxylate Superplasticizer

Study on UV aging resistance of nano-TiO2/montmorillonite/styrene-butadiene rubber composite modified asphalt based on rheological and microscopic properties

Improvements in setting behavior and strengths of cement paste/mortar with EVA redispersible powder using C-S-Hs-PCE

Research on the fatigue performance of self-compacting concrete structure in CRTSIII slab ballastless track under the action of heavy haul train

Preparation and flexural fatigue resistance of self-compacting road concrete incorporating nano-silica particles

Comparison of performances of early aged pre-vibrated cement-stabilized macadam formed by different compactions

This research presents a method to solve the problem of poor durability of cement pavement caused by long-term use of deicing salt as well as improve the salt-frost resistance of self-developed sup...

Salt-frost resistance and mechanism analysis of super-hydrophobic pavement cement concrete for different deicing salts

As a kind of granular waste with complex composition and alkali corrosiveness, concrete slurry waste (CSW) has severe recycling limitations in the Ordinary Portland cement (OPC). Considering this, a new type of geopolymer, prepared by granulated blast furnace slag/fly ash, concrete slurry waste, and powdered activators (sodium carbonate and different silicon sources including sodium metasilicate pentahydrate and silica fume), was adopted to conduct a comparative study with the OPC counterpart. In this study, the homogenized CSW was mixed in the OPC and geopolymer with a constant ratio of 50 wt%, respectively. Then the properties were studied in terms of the flowability, setting times, mechanical strengths, and microstructures. The results showed that better flowability (200mm) could be achieved in the obtained geopolymer than in the OPC reference group (95mm) by increasing the powdered activators. The setting time of the OPC was significantly shortened due to the addition of CSW. The strengths of geopolymer were supported by the produced C-A-S-H and carbonates, with less chemically bonded water than the hydration products in the reference group. The dominant size of pores in the hardened geopolymer was much smaller than that in the OPC group which was 80nm. Silica fume could be the alternate of the sodium metasilicate pentahydrate and had an insignificant negative impact on the fresh and hardened properties and microstructures of the geopolymer when the incorporation rate was within 5%.

Wei Zeng

Papers

Preparation and flexural fatigue resistance of self-compacting road concrete incorporating nano-silica particles

Comparison of performances of early aged pre-vibrated cement-stabilized macadam formed by different compactions

Salt-frost resistance and mechanism analysis of super-hydrophobic pavement cement concrete for different deicing salts

Basic Properties of fly Ash/Slag -Concrete Slurry Waste Geopolymer Activated by Sodium Carbonate and Different Silicon Sources