Multivariate Statistical Analysis of the Wfarddc North American Fly Ash Database

1991 ◽  
Vol 245 ◽  
Author(s):  
Hans S. Pietersen ◽  
Simon P. Vriend ◽  
Gregory J. Mccarthy
Keyword(s):  
Compressive Strength ◽  
Statistical Analysis ◽  
Specific Gravity ◽  
North American ◽  
Activity Index ◽  
Pozzolanic Activity ◽  
Mineral Admixtures ◽  
Fly Ashes ◽  
Glass Chemistry ◽  
Bulk Chemistry

ABSTRACTThe database of chemical, mineralogical and physical characteristics of North American Fly ashes, assembled by the WFARDDC in North Dakota, was analyzed using multivariate statistics. Prior to the multivariate analysis, the data were rearranged in subgroups containing information on bulk-chemistry, glass chemistry, mineralogy and ASTM physical test results. These groups were analyzed individually. The multivariate technique used was Fuzzy C-Means Cluster Analysis, combined with Non-Linear Mapping. Analysis of the data-set indicates a relation between glass network former and network modifier content. The database shows that a subdivision on the basis of bulk CaO (< 11%; 11–20%; >20%) correlates well with the ASTM C618 Σ(SiO2 +Al2O3 +Fe2O3) and/or specific gravity. Mineralogical data indicate a subdivision into clusters containing varying amounts of mullite, quartz and/or ferrite spinel and a variety of Ca-containing minerals; high CaO ashes usually have high Ca-mineral contents. Of the CaO containing minerals, only portlandite contributed slightly to the compressive strength as defined by ASTM C618. Analysis of glass chemistry reveals smaller differences in absolute amounts of major oxides than would be expected on the basis of bulk chemistry alone. Surprisingly, the total glass content does not contribute significantly to 28 day compressive strength; multiple regression analysis only indicates a significant relation of particle size and specific gravity with the ASTM Pozzolanic Activity Index (portland cement). The Pozzolanic Activity Index with lime seems to be of limited importance in evaluating the performance of fly ashes as mineral admixtures in concrete. On the basis of the statistical analysis, suggestions for selection of important classifying variables are made.

The Effect of Substituting Rdf on the Physical and Environmental Properties of Coal Fly Ash

1988 ◽  
Vol 136 ◽  
Author(s):  
Ashaari B. Mohamad ◽  
David L. Gress
Keyword(s):  
Compressive Strength ◽  
Fly Ash ◽  
Physical Properties ◽  
Activity Index ◽  
Coal Fly Ash ◽  
Pozzolanic Activity ◽  
Portland Cement Concrete ◽  
Fly Ash Concrete ◽  
Refuse Derived Fuel ◽  
Cadmium And Lead

ABSTRACTRefuse-derived-fuel (RDF) consisting mainly of waste paper and plastics is a viable fuel source for the production of power. An experimental test burn partially substituting coal with RDF was undertaken by the Public Service of New Hampshire at the Merrimack Power Station.Five percent and ten percent RDF were substituted, on a BTU basis, for coal in the test bums. The chemical and physical properties of the resulting fly ash were determined. Twelve test burn days were run with 4 days of 5% RDF and 8 days of 10% RDF. Emphasis was placed on investigating the effect of the RDF fly ash on Portland cement concrete.Most of the chemical and physical properties of the coal-RDF fly ash were found to be comparable with ordinary coal fly ash except for the amount of cadmium and lead, the pozzolanic activity index and the compressive strength of fly ash concrete. Cadmium and lead were at average levels of 5.1 ppm and 102.6 ppm for the 5% RDF, and 7.8 ppm and 198.3 ppm for the 10% RDF, respectively. Although the pozzolanic activity index of coal-RDF fly ash increases over normal coal fly ash, preliminary results show that the 28-day compressive strength of concrete with direct replacement of cement and sand decreases by up to 30%. Leaching tests on crushed concrete were conducted to evaluate the environmental effect of acid rain.

scholarly journals Complex Characterization and Behavior of Waste Fired Brick Powder-Portland Cement System

Materials ◽  
2019 ◽  
Vol 12 (10) ◽  
pp. 1650 ◽  
Author(s):  
Viviana Fátima Rahhal ◽  
Mónica Adriana Trezza ◽  
Alejandra Tironi ◽  
Claudia Cristina Castellano ◽  
Milena Pavlíková ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Portland Cement ◽  
Dilution Effect ◽  
Pozzolanic Activity ◽  
Mineral Admixtures ◽  
Blended Cements ◽  
Ceramic Waste ◽  
Brick Powder ◽  
Cement System ◽  
And Performance

Two waste fired brick powders coming from brick factories located in Argentine and Czech Republic were examined as alternative mineral admixtures for the production of blended cements. In pastes composition, local Portland cements (Argentine and Czech) were substituted with 8–40%, by mass, with powdered ceramic waste. For the ceramic waste-Portland cement system, workability, the heat released, pozzolanity, specific density, compressive strength, hydrated phases, porosity, and pore size distribution were tested. The relevance of the dilution effect, filler effect, and pozzolanic activity was analyzed to describe the general behavior of the pozzolan/cement system. The properties and performance of cement blends made with finely ground brick powder depended on the composition of ceramic waste and its reactivity, the plain cement used, and the replacement level. Results showed that the initial mini-slump was not affected by a low ceramic waste replacement (8% and 16%), and then it was decreased with an increase in the ceramic waste content. Brick powder behaved as a filler at early ages, but when the hydration proceeded, its pozzolanic activity consumed partially the calcium hydroxide and promoted the formation of hydrated calcium aluminates depending on the age and present carbonates. Finally, blended cements with fired brick powder had low compressive strength at early ages but comparable strength-class at later age.

scholarly journals Pozzolanic activity of argentine vitreous breccia containing mordenite

2020 ◽  
Vol 70 (337) ◽  
pp. 208
Author(s):  
V. L. Bonavetti ◽  
V. F. Rahhal ◽  
F. Locati ◽  
E. F. Irassar ◽  
S. Marfil ◽  
...  
Keyword(s):  
Compressive Strength ◽  
Activity Index ◽  
Staining Technique ◽  
Pozzolanic Reaction ◽  
Exchange Capacity ◽  
Pozzolanic Activity ◽  
Raw Material ◽  
Blue Staining ◽  
Early Hydration ◽  
Blended Cements

A vitreous breccia with variable amount of mordenite was studied for its use as pozzolan. The raw material was characterized by optical and scanning electron microscopy (SEM), X-ray diffraction (XRD), and the zeolite content was estimated by the methylene blue staining technique. After being ground, physical characteristics, cation exchange capacity (CEC), pozzolanicity, and the compressive strength activity index (SAI) were determined. The staining technique and the CEC measurement were used to evaluate the average content of zeolite. The vitreous breccia has pozzolanic activity after 7 days, the water demand increases slightly, and its addition stimulates the early hydration of portland cement. At later ages, the pozzolanic reaction around the grains, as revealed by SEM studies, improves the compressive strength of blended cements having a SAI > 0.85 at 28 days.

Activity Evaluation of a Tailing in a Cementitious System

2017 ◽  
Vol 726 ◽  
pp. 515-520 ◽  
Author(s):  
Bing Hao Li ◽  
Lian Zhen Xiao ◽  
Ya Qing Fu
Keyword(s):  
Compressive Strength ◽  
Electrical Resistivity ◽  
Fly Ash ◽  
Activity Index ◽  
Resistivity Measurement ◽  
Mineral Admixture ◽  
Mineral Admixtures ◽  
Electrical Resistivity Measurement ◽  
Activity Evaluation ◽  
Two Peaks

Hydration activity of a tailing is evaluated by the hydration rate obtained from the electrical resistivity measurement and compressive strength in a cementitious hydration system as a mineral admixture. A plain paste and the pastes with tailing or fly ash by replacement of cement at water-binder ratio of 0.4 are prepared. The electrical resistivity of the paste samples was measured in 168h(7d) by a non-contact resistivity technique. Hydration activity of the tailing was also evaluated by measuring the compressive strength at the curing ages of 3d~90d to confirm the results from the electrical resistivity. It is found that the addition of a mineral admixture delays the occurrence of two peaks on the electrical resistivity differential curve and the delayed times are 3.32h and 6.10h for the sample with tailing, and 0.78h, 3.49h for the sample with fly ash. The rate values on the two peaks are decreased with incorporation of the tailing or fly ash. The activity evaluation results on the mineral admixtures from the resistivity measurement are consistent with the strength results before 7d. The resistivity as an activity index can provide a simple and fast way to evaluate mineral material activity at early ages. The effect of tailing and fly ash on compressive strength for a long term was also analyzed and the micro-structure of the pastes at 7d and 28d were observed by SEM.

scholarly journals Effects of the incorporation of residue of masonry on the properties of cementitious mortars

2020 ◽  
Vol 19 (3) ◽  
pp. 407-421
Author(s):  
Yimmy Fernando Silva ◽  
◽  
David A. Lange ◽  
Silvio Delvasto ◽  
◽  
...  
Keyword(s):  
Compressive Strength ◽  
Activity Index ◽  
Setting Time ◽  
Drying Shrinkage ◽  
Heat Of Hydration ◽  
Cementitious Material ◽  
Pozzolanic Activity ◽  
Construction And Demolition Waste ◽  
Demolition Waste ◽  
Supplementary Cementitious Material

This paper presents results of an experimental study of a residue of masonry (RM), sampled from a construction and demolition waste (CDW), added as a supplementary cementitious material (SCM) to partially replace up to 50% of Portland cement in the preparation of mortars. The pozzolanic activity (fixed lime and strength activity index), setting time, heat of hydration, the (autogenous and drying) shrinkage and compressive strength tests were carried out. The results show how the RM has a positive activity because the increase of RM replacement level in the mortars generates a lower heat of hydration and autogenous and drying shrinkage. The fixed lime at 28 and 180 days, indicating that the RM exhibits in some degree pozzolanic activity and the Strength Activity Index (SAI) was 77.13% and 84.36% of the compressive strength of 100% OPC mortar at the 7 and 28 days respectively, which conformed to ASTM C311. These results indicate that RM should be considered appropriated for using as a supplementary cementitious material.

The Pozzolanic Activity of the Coal Gauge and its Evaluation

2013 ◽  
Vol 683 ◽  
pp. 509-513
Author(s):  
Jie Yu Chen ◽  
Tao Sun ◽  
Xiao Yan Zhu ◽  
Xin Rong Lei
Keyword(s):  
Compressive Strength ◽  
Thermal Treatment ◽  
Specific Gravity ◽  
Great Influence ◽  
Pozzolanic Activity ◽  
X Ray Diffraction ◽  
X Ray ◽  
Temperature Range ◽  
Active Alumina ◽  
Activity Temperature

The pozzolanic activity of the coal gauge obtained by thermal treatment is evaluated. X-ray diffraction and the compressive strength of the geopolymer prepared by the heated coal gauge are seen as the pozzolanic activity evaluation basis. The active alumina, degrees of dehydroxylation and the specific gravity of coal gauge at different temperature are measured. The results show that the pozzolanic activity of the coal gauge heated at 600°C for 4h is highest in the pozzolanic activity temperature range of 550-850°C and bad at lower 500°Cand higher 900°C. The degree of dehydroxylation, the active alumina and the specific gravity have great influence on the pozzolanic activity of calcined coal gauge. In the temperature range of the pozzolanic activity, the higher is the degree of dehydroxylation and the active alumina, the greater the pozzolanic activity is. The minimum is the specific gravity, the greater the pozzolanic activity is. So, the pozzolanic activity of the coal gauge can be evaluated approximatively by them.

scholarly journals Basic Properties of Calcined Underground Ant Nest Materials and Its Influence on the Compressive Strength of Concrete

Materials ◽  
2019 ◽  
Vol 12 (7) ◽  
pp. 1191 ◽  
Author(s):  
Zhou ◽  
Zhu ◽  
Qu
Keyword(s):  
Compressive Strength ◽  
Activity Index ◽  
Clay Content ◽  
Particle Morphology ◽  
Pozzolanic Activity ◽  
Ant Nest ◽  
Compressive Strength Of Concrete ◽  
Dead Plant ◽  
Nest Materials ◽  
Curing Age

Underground ant nests are typically made of soil and rubble mixed with dead plant bodies, ant secretions, and other organic substances. The clay content is high, and the natural clay materials show pozzolanic activity after calcination. In this study, the underground ant nest materials of Iridomyrmex anceps, which is a common ant in the Shanghai area, are calcined and ground, and the material properties of calcined ant nest clay powder (CANCP) are characterized from six aspects: chemical composition, particle morphology, specific gravity, specific surface area, particle size distribution and pozzolanic activity index. The pozzolanic activity of CANCP is evaluated by the strength contribution rate of pozzolanic activity, revealing that CANCP is beneficial to the strength of the mortar system from an early age. The influence of CANCP on the compressive strength of concrete is analyzed using three aspects, namely, content, curing age and calcination temperature, and it is found that the three aspects of CANCP have a strong influence on the compressive strength of concrete.

scholarly journals Feasibility of using pozzolanicity tests to assess reactivity of wood biomass fly ashes

2021 ◽  
Vol 72 (12) ◽  
pp. 1145-1153
Keyword(s):  
Electrical Conductivity ◽  
Activity Index ◽  
Pozzolanic Activity ◽  
Material Strength ◽  
Wood Biomass ◽  
Fly Ashes ◽  
Pozzolanic Reactivity ◽  
Pozzolanic Material

Pozzolanic activity of materials can initially be assumed from the quantity of the pozzolanic oxides SiO2, Al2O3 and Fe2O3. Some of the methods for assessing pozzolanic reactivity of materials include measurement of CaO consumption (Frattini test), decrease in electrical conductivity and pH of a solution containing pozzolanic material, or measurement of an increase in strength of mortar with replacement of cement by pozzolanic material (strength activity index, SAI). The above-mentioned pozzolanicity tests are used in this study to evaluate reactivity of wood biomass fly ashes (WBA-F). The results presented in the paper show that only the SAI method can fully reveal the hydraulic and pozzolanic activity of WBA-F.

Selected Properties of Parallel Strand Lumber Made from Southern Pine and Yellow-Poplar

Holzforschung ◽  
2003 ◽  
Vol 57 (2) ◽  
pp. 207-212 ◽  
Author(s):  
Y. Liu ◽  
A.W.C. Lee
Keyword(s):  
Compressive Strength ◽  
Shear Strength ◽  
Specific Gravity ◽  
Moisture Content ◽  
Dimensional Stability ◽  
Modulus Of Rupture ◽  
Southern Pine ◽  
Yellow Poplar ◽  
Average Modulus ◽  
Parallel Strand Lumber

Summary This study was conducted to explore basic physical and mechanical properties of parallel strand lumber (PSL) made exclusively from southern pine and yellow-poplar, respectively, and to examine their relationships using statistical analysis. Small specimens were prepared from commercial southern pine PSL and yellow-poplar PSL billets and tested for specific gravity, moisture content, dimensional stability, bending properties, shear strength and compressive strength. Results indicate average specific gravity of southern pine PSL is higher than that of yellow-poplar PSL, while their average moisture content and dimensional stability are very similar. Southern pine PSL has higher average modulus of elasticity but lower average modulus of rupture than yellow-poplar PSL. While average longitudinal shear strength does not exhibit differences between southern pine PSL and yellow-poplar PSL, average compressive strength of southern pine PSL is higher than that of yellow-poplar PSL. There are positive correlations among modulus of elasticity, modulus of rupture and specific gravity. PSL improves some properties of solid wood from which PSL is made.

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