scholarly journals Experimental Study on the Influence of PVA Content on the Performance of Grouting Material in Deep Stope

Geofluids ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-11
Author(s):  
Bin Liu ◽  
Liming Yin ◽  
Juntao Chen ◽  
Ming Li ◽  
Daozeng Tang ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Setting Time ◽  
Practical Significance ◽  
Peak Period ◽  
Grouting Material ◽  
Coupling Characteristics ◽  
Grouting Materials ◽  
And Control ◽  
Water Hazards

Based on laboratory experiments, the paper researches the effect of polyvinyl alcohol (PVA) content on the performance of fly ash-based cement grouting materials. The test results show that the addition of PVA has limited effect on the initial and final setting time and brings a certain but minor delay on the appearance of the hydration peak period. It enhances cement hydration during the hydration slow down period. The impermeability of PVA to the grouting material is obviously improved, and it increases with the growing amount of PVA content. PVA improves the flexural strength and compressive strength of the sample block to varying degrees, and the improvement on flexural strength is more obvious than that on the compressive strength. It has a significant effect on the mechanical properties of the grouting material and can effectively improve the rock mass’s hydraulic coupling characteristics. It also has great application value and practical significance for the prevention and control of water hazards in deep coal stopes.

scholarly journals Effects of Aluminum Sulfate and Quicklime/Fluorgypsum Ratio on the Properties of Calcium Sulfoaluminate (CSA) Cement-Based Double Liquid Grouting Materials

Materials ◽  
2019 ◽  
Vol 12 (8) ◽  
pp. 1222 ◽  
Author(s):  
Yuli Wang ◽  
Jie Yu ◽  
Junjie Wang ◽  
Xuemao Guan
Keyword(s):  
Compressive Strength ◽  
Aluminum Sulfate ◽  
Setting Time ◽  
Strength Properties ◽  
X Ray Diffraction ◽  
Cement Slurry ◽  
Calcium Sulfoaluminate ◽  
Optimum Content ◽  
Grouting Material ◽  
Grouting Materials

Grouting materials are used frequently in grouting reinforcement projects, such as mining and coastal engineering. Double liquid grouting materials are mostly used because of the fast setting and high early strength properties when the two slurries are mixed together but high fluidity when the two slurries are separated. In our study, double liquid grouting materials were developed from CSA cement (slurry A), quicklime and fluorgypsum (slurry B). Aluminum sulfate was added in slurry B in order to counteract any adverse effects caused by the fluorgypsum, such as the decreased early compressive strength and the prolonged setting time. The effects of aluminum sulfate content and the quicklime/fluorgypsum ratio on the setting time, hydration heat, and compressive strength of the double liquid grouting materials were investigated, and the hydration products were characterized through thermogravimetry-differential thermal analysis (TG-DTA), X-ray Diffraction (XRD), and Scanning Electron Microscope (SEM) tests. The results show that the addition of aluminum sulfate can shorten the setting time and increase compressive strength at both early and later ages. Considering the setting time and compressive strength of double liquid grouting material at the same time, the optimum content of aluminum sulfate was found to be 2%, and the optimum ratio of quicklime/fluorgypsum was found to be 2:8. The values of the optimum content of aluminum sulfate and ratio of quicklime/fluorgypsum were verified from theoretical analysis.

scholarly journals Experimental Study of Cement Alkali-Resistant Glass Fiber (C-ARGF) Grouting Material

Materials ◽  
2020 ◽  
Vol 13 (3) ◽  
pp. 605 ◽  
Author(s):  
Zhenyue Shi ◽  
Qingbiao Wang ◽  
Lei Xu
Keyword(s):  
Tensile Strength ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Glass Fiber ◽  
High Strength ◽  
Strength Ratio ◽  
Karst Tunnel ◽  
Grouting Material ◽  
Early Strength ◽  
Grouting Materials

Mixing alkali-resistant glass fiber (ARGF) into grouting slurry can prevent the development of cracks; thus, understanding the properties of ARGF grouting material is important for applications in engineering. Two types of ARGFs (Cem-FIL®60 and Anti-Crak®HD) were selected as mixing materials, and their performance was tested in four areas, namely, compressive strength, tensile strength, flexural strength, and impervious performance, under four different mixing amounts of fiber (0%, 0.25%, 0.5%, and 1.0%). Results demonstrate that the addition of ARGF increased the compressive strength and tensile strength of the grouting slurry, and the best performance was at 0.5%. The effect on the flexural strength and impervious performance was related to the mixing amount, and the fiber may have induced a counter-effect for certain amounts of added ARGF. Mixing ARGF could increase the early strength ratio of grout; however, a high early strength ratio did not necessarily result in high strength, as the flexural strength did not change synchronously with the early strength ratio; a similar pattern was found for the impermeability. Cem-FIL®60 had a better effect on the properties of grouting materials than Anti-Crak®HD. These results were successfully applied in the water-plugging and reinforcement engineering of a karst tunnel.

Research on Sand Gradation to Ultra Strength Grouting Material Properties

2014 ◽  
Vol 507 ◽  
pp. 300-305
Author(s):  
Chang Zheng Sun ◽  
Xiao Ping Zhang ◽  
Hai Nan Zhao ◽  
Qiang Gao
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Material Properties ◽  
Setting Time ◽  
Fine Sand ◽  
Coarse Sand ◽  
Medium Sand ◽  
Final Setting Time ◽  
Grouting Material ◽  
Early Strength

The gradation of coarse sand, medium sand and fine sand on fluidity initial, final setting time, flexural strength, compressive strength, and other properties and structure, of ultra early strength grouting material, was explored. The quartz sand gradation of cement sand ratio 1.0 was systematically studied. The results showed that, the coarse sand, medium sand and fine sand mixed according to the reasonable distribution, when glue sand ratio was 1.0-1.5, ultra-early-strength grouting material, with final setting time for 50-60(min), the initial fluidity greater than 320(mm), 0.5h fluidity greater than 280(mm), 2h compressive strength of 35.6(MPa), 1d flexural strength greater than 13(MPa), 28d compressive strength over 93(MPa), achieved the free vibration.

Effect of Metakaolin on Geopolymer Industry

2019 ◽  
pp. 49-70
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Flexural Strength ◽  
Reaction Mechanisms ◽  
Ordinary Portland Cement ◽  
Setting Time ◽  
Experimental Studies ◽  
Acid Attack ◽  
Repair Materials ◽  
Hardened State

This chapter discusses the effects of metakaolin (MK) on geopolymer mortar and concrete industries. The research topics of MK-based geopolymer cover reaction mechanisms and kinetics. This chapter aims at augmenting knowledge about enhancing mechanical properties of geopolymer mortars/concrete using MK. Specifically, this chapter presents literature studies as well as current experimental studies which delineate the effect of MK on fresh and hardened-state properties of geopolymer mortars (GPMs). Properties and characteristics of metakaolin are explained followed by properties of fresh MK mortars. Properties of hardened MK concrete and durability aspects of MK mortars are explained. Applications of MK-based geopolymers and metakaolin-based geopolymers as repair materials are also included in this chapter. The results of using MK-based GPMs revealed improved workability, enhanced setting time, increased density, higher compressive strength, flexural strength, and resistance against acid attack than conventional ordinary portland cement mortar/concrete.

scholarly journals Preparation of Portland Cement with Gold Ore Tailings

2019 ◽  
Vol 2019 ◽  
pp. 1-9 ◽  
Author(s):  
Qiang Wang ◽  
Geng Yao ◽  
Xiangnan Zhu ◽  
Junxiang Wang ◽  
Peng Wu ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Portland Cement ◽  
Raw Materials ◽  
Setting Time ◽  
Hydration Product ◽  
Difficult Problem ◽  
Initial Setting Time ◽  
Gold Ore ◽  
Curing Age

The disposal of gold ore tailings (GTs) has been a very difficult problem for a long time. Thus, this study explored a new approach to the management of GTs by preparing Portland cement. Physical properties, reaction mechanisms, and hydration product types of cement prepared with GTs (C-GTs) and ordinary Portland cement (C-SS) were compared. X-ray diffraction (XRD), thermogravimetric (TG), and scanning electron microscope energy-dispersive spectroscopy (SEM-EDS) analysis techniques were used to study the mineralogical phases of the clinker and raw materials, hydration product types, and microtopography. The consistency, setting time, flexural strength and compressive strength values of the cement samples (C-GTs and C-SS), and burnability of the raw materials were also studied. The burnability analysis indicated that GTs provided a higher reactivity. The XRD results showed that the clinker phases of the C-GTs were C3S, C2S, C3A, and C4AF. The XRD, TG, and SEM-EDS results showed that the hydration products were flaky calcium hydroxide, rod-shaped ettringite, and granular C-S-H gels. Its compressive strength and flexural strength were, respectively, 30.4 MPa and 6.1 MPa at the curing age of 3 days and 59.1 MPa and 9.8 MPa at the curing age of 28 days, which were slightly higher than those of the C-SS. Furthermore, the results showed that the consistency, initial setting time, and final setting time for the two kinds of cement were similar, which further suggested that GTs could be used to prepare Portland cement.

Research on Multivariate Composite Super early Strength Grouting Materials

2013 ◽  
Vol 477-478 ◽  
pp. 990-995
Author(s):  
Xiao Ping Zhang ◽  
Chang Zheng Sun ◽  
Tong Feng Zhao
Keyword(s):  
Compressive Strength ◽  
High Performance ◽  
Ordinary Portland Cement ◽  
High Alumina ◽  
Flow Ratio ◽  
Initial Flow ◽  
Growth Structure ◽  
Grouting Material ◽  
Early Strength ◽  
Grouting Materials

Super early strength high performance grouting material was produced using high alumina cement, ordinary portland cement, gypsum and silica fume. The different glue sand ratio and the cement sand ratio 1.0 mix microstructure were studied systematically. The results showed that the system with a variety of admixture using hingh mortar ratio can be prepared for the initial flow ratio greater than 325{mm},, 30min flow greater than 280{mm}, 2h compressive strength 34.80{MPa}, 24h bending over 13.82{MPa}, 28d compressive strength greater than 99.90{MPa}, 28d compressive strength greater than 56d compressive strength. The system of early SEM microstructures showed good crystal growth, structure compact.

scholarly journals Effect of fly ash on physical and mechanical properties of mortar

2019 ◽  
Vol 17 (6) ◽  
pp. 35
Author(s):  
Vu-An Tran
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Fly Ash ◽  
Flexural Strength ◽  
Water Absorption ◽  
Thermal Power ◽  
Setting Time ◽  
Physical And Mechanical Properties ◽  
Flow Density ◽  
Control Specimen

This research investigates the physical and mechanical properties of mortar incorporating fly ash (FA), which is by-product of Duyen Hai thermal power plant. Six mixtures of mortar are produced with FA at level of 0%, 10%, 20%, 30%, 40%, and 50% (by volume) as cement replacement and at water-to-binder (W/B) of 0.5. The flow, density, compressive strength, flexural strength, and water absorption tests are made under relevant standard in this study. The results have shown that the higher FA content increases the flow of mortar but significantly decreases the density of mixtures. The water absorption and setting time increases as the samples incorporating FA. Compressive strength of specimen with 10% FA is approximately equal to control specimen at the 91-day age. The flexural strength of specimen ranges from 7.97 MPa to 8.94 MPa at the 91-day age with the best result for samples containing 10% and 20% FA.

Preparation of Sulfoaluminate Cement Using Industrial Waste Residue

2011 ◽  
Vol 396-398 ◽  
pp. 380-385
Author(s):  
Lei Wang ◽  
Ye Wang ◽  
Tian Hua Yang ◽  
Run Dong Li
Keyword(s):  
Mechanical Properties ◽  
Compressive Strength ◽  
Corrosion Resistance ◽  
Flexural Strength ◽  
Physical Properties ◽  
Industrial Waste ◽  
Sintering Temperature ◽  
Setting Time ◽  
Cement Clinker ◽  
Environmental Technology

Large amount of emissions from industrial waste residue to the environment has caused serious pollutions. Utilization way to using industrial waste residue preparing sulfoaluminate cement (SAC) is got much attention of scholars both at home and abroad. It summarized the present researches for preparation of SAC from industrial waste residue (IWR). Sintering temperature, mineral composition, physical properties (fineness, standard viscosity, setting time), mechanical properties (compressive strength, flexural strength) and corrosion resistance of cement clinker were analyzed. Preparation of SAC clinker using IWR is a very promising environmental technology.

scholarly journals Effect of Additives on the Rheological and Mechanical Properties of Microfine-Cement-Based Grout

2019 ◽  
Vol 2019 ◽  
pp. 1-10
Author(s):  
Shuai Zhang ◽  
Weiguo Qiao ◽  
Yanzhi Li ◽  
Kai Xi ◽  
Pengcheng Chen
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Compressive Strength ◽  
Fly Ash ◽  
Mechanical Performance ◽  
Setting Time ◽  
Effect Of Additives ◽  
Microfine Cement ◽  
The Stability ◽  
Grouting Materials

Enhancement of the fluidity and mechanical performance of grouting materials has proven to be an effective method of seepage prevention in geotechnical engineering. In this research, a microfine-cement-based grout mixed with microfine fly ash (MFA), nano-CaCO3 (NC), and superplasticizer (SP) was designed to improve the rheological and mechanical properties of grouting materials, and the particle size distribution, fluidity, spreading ability, bleed capacity, setting time, and mechanical properties were studied. A water/solid (W/S) ratio of 1.2 was selected, and the contents of MFA, NC, and SP by mass of microfine cement (MC) were 0–40%, 0–2.0%, and 1.5%, respectively. The results showed that MFA and 1.5% SP improved the fluidity and spreading ability of fresh grouts, while prolonging the setting time. The addition of NC can increase the yield stress and plastic viscosity and decrease the fluidity and spreading ability; nevertheless, it obviously enhances the stability and shortens the setting time of grouts. The addition of MFA and 1.5% SP reduced the compressive strength of hardened grouts; however, the addition of NC improved the mechanical properties.

Properties of Cement Mortars Mixed with SiO2 and CaCO3 Nanoparticles

2013 ◽  
Vol 539 ◽  
pp. 244-248
Author(s):  
De Zhi Wang ◽  
Yin Yan Zhang ◽  
Yun Fang Meng
Keyword(s):  
Compressive Strength ◽  
Flexural Strength ◽  
Cement Mortar ◽  
Negative Impact ◽  
Setting Time ◽  
Water Requirement ◽  
Mineral Admixtures ◽  
Cement Pastes ◽  
Optimal Replacement ◽  
Cement Mortars

Water requirement of normal consistency, setting time and soundness of cement pastes mixed with SiO2 and CaCO3 nanoparticle and the flexural strength and compressive strength of cement mortars mixed with SiO2 and CaCO3 nanoparticles were experimentally studied. Results indicated that the added nano-SiO2 and nano-CaCO3 with a mass account of 4.0 wt. % decreased the setting time and increased the water requirement of normal consistency, flexural strength and compressive strength. And these nanoscaled mineral admixtures did not have a negative impact on cement soundness. The optimal replacement levels of cement by SiO2 and CaCO3 nanoparticles for producing cement mortar with improved strength were 2.0 and 4.0 wt.% respectively.

Sign in / Sign up

Export Citation Format

Share Document