Related Experiment Video
Updated: Aug 14, 2026
11:14
Two-way Valorization of Blast Furnace Slag: Synthesis of Precipitated Calcium Carbonate and Zeolitic Heavy Metal Adsorbent
Published on: February 21, 2017
Response Surface Optimization of Fly Ash-Carbide Slag-Bentonite-Based Whole-Tailings Backfill: Multi-Objective Mix
Junhui Yao1,2, Jianyuan Jin1,2, Yin Chen3
1Key Laboratory of Green and Efficient Mining and Ecological Restoration in High-Altitude Arid Regions of Xinjiang, Urumqi 830047, China.
Materials (Basel, Switzerland)
|August 13, 2026
Summary
This study optimized fly ash-carbide slag-bentonite (FCB) for low-carbon mine backfill. Optimal mix design reduces cement use, enhancing solid waste utilization and compressive strength.
Area of Science:
- Materials Science
- Geotechnical Engineering
- Sustainable Construction
Background:
- Reducing cement consumption in mine backfill is crucial for low-carbon systems.
- Synergistic utilization of multi-source solid wastes is key for sustainable backfill materials.
Purpose of the Study:
- Optimize fly ash-carbide slag-bentonite-based whole-tailings backfill (FCB) performance.
- Investigate the effects of key parameters on fluidity, setting time, and strength.
- Analyze microstructural mechanisms for enhanced backfill properties.
Main Methods:
- Box-Behnken response surface design for optimization.
- Experimental investigation of fluidity, setting time, and 28-day uniaxial compressive strength.
- Microstructural analysis using X-ray Diffraction (XRD) and Scanning Electron Microscopy (SEM).
Main Results:
- Statistically significant quadratic models were developed, with strength model showing best fit.
- Replacement ratio and bentonite content were primary factors influencing FCB performance.
- Optimal mix (A=0.58, B=2.71, C=4.99%) achieved validation errors <5%.
Conclusions:
- Optimized FCB formulation significantly reduces cement usage and enhances solid waste utilization.
- Microstructural analysis revealed C-(A)-S-H gel and AFt as primary hydration products.
- Lower replacement ratios and appropriate bentonite content yield higher compressive strength and continuous matrix morphology.
Related Concept Videos
01:14Design Example: Managing Concrete Workability
This example deals with managing the workability of concrete for a raft foundation project under hot weather conditions. Workability is crucial for ensuring the concrete is easy to place, compact, and finish. In this scenario, a slump test — a common method to measure the workability of fresh concrete — initially indicated low workability. This was attributed to the rapid water loss from the concrete mix, exacerbated by the high temperatures causing the course aggregates to heat up.
To address...
To address...
01:24Design Example: Aggregate Gradation
The right type and quality of aggregates are crucial for concrete as they significantly influence its properties, mix proportions, and cost-effectiveness. If different sources are available for sand, the commonly used fine aggregate in concrete, the selection of sand is primarily based on its gradation.
The grading, or particle-size distribution, of sand is determined using sieve analysis, with standard sizes ranging from 150 μm to 10 mm (ASTM No. 100 sieve to 3⁄8 in. sieve). Sand is sampled...
The grading, or particle-size distribution, of sand is determined using sieve analysis, with standard sizes ranging from 150 μm to 10 mm (ASTM No. 100 sieve to 3⁄8 in. sieve). Sand is sampled...
01:21Pozzolans
Pozzolans are siliceous or aluminous materials blended with Portland cement. They interact with the calcium hydroxide produced during the hydration of Portland cement and contribute to improved strength and durability of concrete. The pozzolanic activity, a measure of a pozzolan's effectiveness, is typically assessed using the strength activity index, as defined in ASTM C 618-93, which calculates the ratio of the compressive strength of cement mixtures with and without pozzolan.
Fly ash is a...
Fly ash is a...
01:29Additives and Fillers in Concrete
Additives and fillers are integral to enhancing the properties of concrete. Pozzolans and blast-furnace slag are additives or admixtures due to their reactions with calcium hydroxide released during cement hydration. Fillers, which are finely ground and similar in fineness to Portland cement, improve concrete attributes such as workability density, and reduce capillary bleeding or cracking. Some fillers possess hydraulic properties or participate in benign reactions within the cement paste.
The...
The...
01:24Factors Affecting Workability
The workability of concrete is a critical characteristic that influences the ease of mixing, handling, and finishing the concrete. It is affected by several factors including water content, aggregate properties, and admixtures like air entrainment. Water plays a fundamental role as it lubricates the concrete mix, facilitating easier movement and placement. However, the water requirement varies depending on the texture and shape of aggregates. Finer particles and angular, rough-textured...
01:28Methods of Medium Optimization
Optimizing growth media enhances microbial proliferation and maximizes product yield. Statistical experimental design methodologies provide structured and reproducible approaches, offering progressively higher levels of robustness and efficiency.The One-Factor-at-a-Time (OFAT) MethodThe One-Factor-at-a-Time (OFAT) method involves adjusting a single variable while keeping all others constant. However, it cannot detect interactions between variables, often leading to suboptimal outcomes when...