Uncompacted Void Content of Fine Aggregate as Quality Indicator of Materials Used in Superpave Mixtures

2000 ◽  
Vol 1723 (1) ◽  
pp. 37-44 ◽  
Author(s):  
Jose Leomar Fernandes ◽  
Reynaldo Roque ◽  
Mang Tia ◽  
Lorenzo Casanova
Keyword(s):  
Shear Strength ◽  
Microscopic Analysis ◽  
Test Methods ◽  
Standard Test ◽  
Design System ◽  
Void Content ◽  
Fine Aggregate ◽  
Direct Shear ◽  
Lower Shear ◽  
Fine Aggregates

The uncompacted void content of fine aggregate, or fine aggregate angularity (FAA), was introduced in the Superpave mixture design system to screen smooth or rounded fine aggregates that may result in mixtures with low rutting resistance. The assumption is that fine aggregates with lower FAA values have lower shear strength (internal friction) and lower resistance to rutting. Continued implementation and evaluation of the Superpave system has led to numerous questions regarding the validity of this assumption and of the use of the FAA test in general. Nine fine aggregates were used to evaluate the FAA test and to determine whether it was a reliable indicator of fine aggregate shear strength. FAA tests were performed using three gradations and the three standard test methods (A, B, and C). Microscopic analysis was conducted to obtain independent visual measures of angularity and texture. Direct shear tests were performed at four confining stresses to determine shear strength parameters. Results indicated that FAA values were related to visual measures of texture and angularity. However, although FAA value contributed to shear strength, it appeared that other factors such as toughness, gradation, and packing characteristics of the fine aggregate overshadow its effect. For the fine aggregates tested, the FAA test rejected aggregates with high shear strength and accepted aggregates with low shear strength. It was concluded that FAA values alone may not be adequate to assess shear resistance of fine aggregate. Direct shear strength may be a better parameter, but additional work is required to evaluate its validity and feasibility.

scholarly journals Experimental Study on Strength of Pervious Concrete by Using Fine Aggregate

2021 ◽  
Vol 9 (12) ◽  
pp. 895-897
Author(s):  
Atif Jawed
Keyword(s):  
Compressive Strength ◽  
Void Ratio ◽  
Rice Husk Ash ◽  
Pervious Concrete ◽  
Void Content ◽  
Fine Aggregate ◽  
Coarse Aggregates ◽  
Fine Aggregates ◽  
Flow Through ◽  
Concrete Matrix

Abstract: Pervious concrete is a special type of concrete, which consists of cement, coarse aggregates, water and if required and other cementations materials. As there are no fine aggregates used in the concrete matrix, the void content is more which allows the water to flow through its bodyThe main aim of this project was to improve the compressive strength characteristics of pervious concrete. But it can be noted that with increase in compressive strength the void ratio decreases. Hence, the improvement of strength should not affect the porosity property because it is the property which serves its purpose. In this investigation work the compressive strength of pervious concrete is increased by a maximum of 18.26% for 28 days when 8% fine aggregates were added to standard pervious concrete Keywords: W/C ratio, pervious Concrete, sugarcane bagasse’s ash, rice husk ash compressive strength, fine aggregates

Influence of Aggregate Properties on Performance of Heavy-Duty Hot-Mix Asphalt Pavements

1996 ◽  
Vol 1547 (1) ◽  
pp. 7-14 ◽  
Author(s):  
Randy C. Ahlrich
Keyword(s):  
Creep Test ◽  
Hot Mix Asphalt ◽  
Test Methods ◽  
Unit Weight ◽  
Void Content ◽  
Fine Aggregate ◽  
Heavy Duty ◽  
Coarse Aggregates ◽  
Aggregate Properties ◽  
Aggregate Particles

Because approximately 85 percent of the total volume of hot-mix asphalt (HMA) mixtures consists of aggregates, the performance of HMA mixtures is greatly affected and influenced by properties of the aggregate blend. The angularity, shape, and texture of the aggregate particles have a significant effect on the performance of HMA mixtures by controlling the mixture's strength and rutting resistance. Rough, angular aggregates have been proved to produce higher-quality HMA pavements than smooth, round aggregates. Current aggregate tests are primarily based on experience and empirical characterization tests. A study was conducted to evaluate test methods that could be used to characterize aggregate properties that are related to HMA rutting potential of heavy-duty pavements. Specifically, FAA aggregate properties and aircraft loading conditions were addressed. The aggregate particles were characterized with the particle index (ASTM D3398), uncompacted void content for fine aggregate (ASTM C1252), modified ASTM C1252 for coarse aggregate, and unit weight and voids in aggregate (ASTM C29). The HMA mixtures were evaluated for rutting potential using the confined repeated load deformation (dynamic creep) test. The laboratory investigation indicated that the tests for particle index, uncom-pacted void content for fine and coarse aggregates, and unit weight and voids in aggregate could be used to characterize the shape and texture of aggregate particles. The study also indicated that the confined creep test could differentiate between HMA mixtures with different aggregate properties in terms of their rutting potential.

Influence of Waste Glass on the Physical Properties of Portland Cement Concrete

2014 ◽  
Vol 798-799 ◽  
pp. 576-581 ◽  
Author(s):  
Edson Jansen Pedrosa Miranda Jr. ◽  
A.E.M. Paiva ◽  
Ermerson Ney Leite Rodrigues
Keyword(s):  
Specific Gravity ◽  
Portland Cement ◽  
Flat Glass ◽  
Waste Glass ◽  
Void Content ◽  
Fine Aggregate ◽  
Portland Cement Concrete ◽  
Cement Concrete ◽  
Fine Aggregates ◽  
Glass Heat

A differential feature of this work was the use of a type of glass that is little used as fine aggregate in concrete – flat glass powder. This study involved an analysis of the influence of the incorporation of waste glass from the grinding and polishing operations of the glass heat treatment process on the void content, water absorption (W/A) and specific gravity of Portland cement concrete. The coarse and fine aggregates used here were crushed stone and sand, respectively. The concrete was produced using 5%, 10% and 20% of waste glass in place of sand, and water-to-cement (w/c) ratios of 0.50, 0.55 and 0.58. The test specimens were cured for 28 days. The results indicated a reduction in the void content when the percentage of waste glass increased to w/c ratios of 0.55 and 0.58. The reduction of the void content reduced the concrete’s W/A and increased its specific gravity. The waste glass used in this study shows a promising potential for use as fine aggregate in Portland cement concrete. However, other variables must be taken into consideration in the subsequent publications.

scholarly journals Microscopic analysis of the alkali-silica reactivity of various origin fine aggregate

2020 ◽  
Vol 322 ◽  
pp. 01025
Author(s):  
Aneta Antolik ◽  
Daria Jóźwiak-Niedźwiedzka ◽  
Kinga Dziedzic ◽  
Karolina Bogusz ◽  
Michał A. Glinicki
Keyword(s):  
Microscopic Analysis ◽  
Mineralogical Composition ◽  
Standard Test ◽  
Test Method ◽  
Alkali Silica Reaction ◽  
Petrographic Analysis ◽  
Fine Aggregate ◽  
Thin Sections ◽  
Alkali Silica Reactivity ◽  
Selection Of

Alkali silica reaction (ASR) is a harmful phenomenon occurring as a result of chemical interactions between sodium and potassium hydroxides in the pore solution and reactive minerals contained in the aggregate. Reactive minerals like microcrystalline, cryptocrystalline or strained quartz dissolve in the alkaline solution and form an expansive gel product. Proper selection of concrete constituents is necessary to ensure the durability of concrete structures. The proper recognition of the aggregate mineralogical composition is a very important element in the process of selection of concrete components due to the risk of ASR occurrence. This paper presents the results of detailed microscopic analysis of alkali-silica reactivity of domestic fine aggregates of various origins. Six siliceous sands from different locations in Poland and one limestone sand were tested. Detailed petrographic analysis was performed on thin sections. In all siliceous sands micro- and cryptocrystalline quartz was recognized as a reactive mineral. Digital image analysis was performed for quantitative assessment of the potential of reactivity of sands. It revealed, that siliceous river sands were the most susceptible to an alkali-silica reaction, which was confirmed by mortar bar expansion test performed according to the standard test method.

scholarly journals Effect of Chemical Composition of Fine Aggregate on the Frictional Behavior of Concrete–Soil Interface under Sulfuric Acid Environment

2021 ◽  
Vol 6 (1) ◽  
pp. 22
Author(s):  
Jie Xiao ◽  
Zhenming Xu ◽  
Yikang Murong ◽  
Lei Wang ◽  
Bin Lei ◽  
...  
Keyword(s):  
Shear Strength ◽  
Fractal Dimension ◽  
Sulfuric Acid ◽  
Rough Surfaces ◽  
Fractal Dimensions ◽  
Friction Angle ◽  
Fine Aggregate ◽  
Direct Shear ◽  
Concrete Plate ◽  
Concrete Plates

Through direct shear tests, this paper aimed to research the effect of fine marble aggregate on the shear strength and fractal dimension of the interface between soil and concrete corroded by sulfuric acid. More realistic concrete rough surfaces than the artificially roughened surfaces were formed by immersing four concrete plates in plastic buckets filled with sulfuric acid for different periods of time. The sand was adopted to imitate the soil. 3D laser scanner was employed to obtain the digital shapes of concrete plates subjected to sulfuric acid, and the rough surfaces were evaluated by fractal dimension. Large direct shear experiments were performed to obtain the curves of the interface shear stress and shear displacement between sand and corroded concrete plate. The method of data fitting was adopted to calculate the parameters of shear strength (i.e., friction angle and the cohesive) and the parameters of the Clough–Duncan hyperbolic model. The results indicated that as the corrosion days increased, the surface of the concrete plate became rougher, the surface fractal dimensions of the concrete corroded by sulfuric acid became bigger, and the interface friction angle became greater. The friction angle of the interface and the fractal dimensions of the surface of the concrete plate containing crushed gravel and marble sand were smaller than that of the concrete plate containing crushed gravel and river sand.

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