Influence of Maximum Particle Size, Fines Content, and Dust Ratio on the Behavior of Base and Subbase Coarse Aggregates

2017 ◽  
Vol 2655 (1) ◽  
pp. 20-26 ◽  
Author(s):  
Rabindra Chaulagai ◽  
Abdolreza Osouli ◽  
Sajjad Salam ◽  
Erol Tutumluer ◽  
Sheila Beshears ◽  
...  
Keyword(s):  
Particle Size ◽  
High Strength ◽  
Maximum Size ◽  
Fines Content ◽  
Coarse Aggregates ◽  
Maximum Particle Size ◽  
Maximum Particle ◽  
Improved Performance ◽  
Aggregate Base

Unbound aggregate base and subbase layers are the main load-bearing layers in a pavement structure. Size and shape properties of these aggregate materials should be controlled to ensure proper workability during construction and improved performance for pavement longevity. The effects of gradation, maximum particle size, fines content (percentage passing the No. 200 sieve), and dust ratio on the quality of aggregates were investigated by performing many soaked California bearing ratio tests on a crushed limestone material. The dust ratio represents the amount of fines content divided by the amount of minus No. 40 sieve material. The dust ratios studied were 0.4, 0.6, and 1.0. Two gradations commonly used in Illinois, with maximum particle sizes of 1 in. and 2 in., were studied to analyze the effect of fines content with respect to maximum particle size in the gradation. A typical range of fines contents (i.e., 5%, 8%, and 12%) was also considered. The results show that the gradation, dust ratio, and fines content should be taken into account in the selection of aggregate properties for stability requirements. Aggregates with larger maximum size particles provide high strength, and they are not affected as much as aggregates with smaller maximum size particles by an increase in fines content. The aggregates with smaller maximum size particles provide lower strength. It was also concluded that samples with a dust ratio of 1.0 do not necessarily result in an aggregate material with low strength.

Effects of maximum particle size of coarse aggregates and steel fiber contents on the mechanical properties and impact resistance of recycled aggregate concrete

2021 ◽  
pp. 136943322110179
Author(s):  
DongTao Xia ◽  
ShaoJun Xie ◽  
Min Fu ◽  
Feng Zhu
Keyword(s):  
Mechanical Properties ◽  
Particle Size ◽  
Steel Fiber ◽  
Impact Resistance ◽  
Recycled Aggregate Concrete ◽  
Recycled Aggregate ◽  
Aggregate Concrete ◽  
Coarse Aggregates ◽  
Maximum Particle Size ◽  
Maximum Particle

Fiber reinforced recycled aggregate concrete has become a new type of green concrete material. The maximum particle size of coarse aggregates and steel fiber contents affect the mechanical properties and impact resistance of recycled aggregate concrete. However, such studies are rare in literature. The present paper shortens the gap through experimental study. A total of 144 specimens of 12 kinds of concrete mixtures were tested, which adopted different steel fiber volume admixtures (0%, 0.8%, 1.0%, 1.2%) and recycled coarse aggregates in different maximum particle sizes (9.5, 19, 31.5 mm) replacing 30% natural coarse aggregate. The compressive strength, splitting tensile strength, and impact resistance of the 12 concrete mixtures were tested. The results showed that the compressive strength, splitting tensile strength, and impact resistance of recycled aggregate concrete increased first and then decreased with the increase of the maximum particle size. The recycled aggregate concrete with the maximum particle size of 19 mm had the highest mechanical properties and impact resistance. Besides, with the increase of steel fiber content, the compressive strength, splitting tensile strength, and impact resistance of recycled aggregate concrete showed an increasing trend. Considering a large amount of experimental data and the coupling effect of steel fiber contents and the maximum particle size of coarse aggregates, the Weibull distribution function was introduced to analyze the impact test results and predict the number of resistance to impact under different failure probabilities. The results showed that the number of blows of the recycled aggregate concrete followed a two-parameter Weibull distribution, and the estimated value of the number of resistance to impact for failure increased with the increase of the failure probability.

scholarly journals Effect of matrix particle size on EPS lightweight concrete properties

2018 ◽  
Vol 251 ◽  
pp. 01027
Author(s):  
Duc Hoang Minh ◽  
Ly Le Phuong
Keyword(s):  
Particle Size ◽  
Compressive Strength ◽  
Lightweight Concrete ◽  
Aggregate Size ◽  
Expanded Polystyrene ◽  
Coarse Aggregates ◽  
Concrete Mixtures ◽  
Maximum Particle Size ◽  
The Matrix ◽  
Maximum Particle

Expanded polystyrene lightweight concrete is a composite which can be made by adding expanded polystyrene aggregate in normalweight concrete (as matrix). The research was focused on the effect of properties and volume of the matrix on the properties of lightweight concrete. The results show that properties of structural polystyrene concrete, such as workability and compressive strength, depend on the aggregate size of the matrix. It also shows that decreasing aggregate size of the matrix is the effective way to increase workability and compressive strength of lightweight concrete. When the density of concretes decrease by 200 kg/m³, slump values decrease by about 20 to 30 mm with lightweight concrete mixtures using maximum particle size of 0.63 mm, while slump values decrease by about 40 mm with the mixtures using maximum particle size of 20 mm. At the same density, the compressive strength of the structural polystyrenre concrete significantly decreased when the coarse aggregate diameter greater than 10 mm. Therefore, coarse aggregates with diameter size are smaller than 10 mm was recommended to use for matrix. In the result, expanded polystyrene concrete with density from 1,400 kg/m³ to 2,000 kg/m³ and compressive strength more than 20 MPa for structural application was made.

A study on the behaviour of soil–geotextile systems in filtration tests

1996 ◽  
Vol 33 (6) ◽  
pp. 899-912 ◽  
Author(s):  
E M Palmeira ◽  
R J Fannin ◽  
Y P Vaid
Keyword(s):  
Particle Size ◽  
Soil Characteristics ◽  
Retention Capacity ◽  
Unidirectional Flow ◽  
Maximum Particle Size ◽  
Theoretical Predictions ◽  
New Apparatus ◽  
Maximum Particle ◽  
Gradient Ratio ◽  
Different Soils

The behaviour of soil–geotextile systems in filtration tests is reported for nonwoven geotextiles under unidirectional flow. A new apparatus was developed to preform filtration tests under an applied vertical stress, and tests were then conducted with different soils and nonwoven geotextiles in order to evaluate the clogging potential and retention capacity of these materials under rather severe combinations of geotextile and soil characteristics. Results show that the geotextiles perfomed well and that observed permeability losses were acceptable even for gradient ratios close to 3. No progressive piping was observed, and it is believed that the retention capacity of the geotextiles may be influenced by their manufacturing process. In general, theoretical predictions for the maximum particle size passing through the geotextile compared well with measurements. Key words: geotextiles, filtration, gradient ratio, permeability, soil retention, clogging.

Performance Evaluation of Al2O3 Powder Dispersion by Bead and Ball Mills

2014 ◽  
Vol 682 ◽  
pp. 32-34 ◽  
Author(s):  
N.S. Belousova ◽  
O.A. Goryaynova ◽  
E.V. Melnikova
Keyword(s):  
Particle Size ◽  
Performance Evaluation ◽  
Ball Mill ◽  
Aqueous Suspension ◽  
Ball Mills ◽  
Powder Dispersion ◽  
Maximum Particle Size ◽  
Bead Mill ◽  
Maximum Particle

In this paper the results of alumina aqueous suspension disaggregation with the help of bead and ball mills are shown. The changing of maximum particle size for50 wt. % and 90 wt. % of powder (from lowest to highest size) in suspension dispersed by a bead mill for one hour and ball mill for 48 hours was fixed. In order to achieve powder parameters given by the manufacturer disaggregating process sets was defined.

Determination of maximum particle size in magnetic fluids

2016 ◽  
Vol 78 (2) ◽  
pp. 269-272 ◽  
Author(s):  
I. M. Aref’ev ◽  
A. V. Lebedev
Keyword(s):  
Particle Size ◽  
Magnetic Fluids ◽  
Maximum Particle Size ◽  
Maximum Particle

Influence of Aggregate on Workability of Self-Compacting Concrete

2012 ◽  
Vol 482-484 ◽  
pp. 1101-1104
Author(s):  
Huan Qiang Liu ◽  
Xi Chen
Keyword(s):  
Particle Size ◽  
Compressive Strength ◽  
Particle Shape ◽  
Shape Index ◽  
Self Compacting Concrete ◽  
Aggregate Gradation ◽  
Self Consolidating Concrete ◽  
Maximum Particle Size ◽  
Maximum Particle

The workability of self-compacting concrete is influenced greatly by aggregate. In this study, the effects of aggregate gradation, maximum particle size, sand percentage and particle shape on the workability of self-consolidating concrete were investigated. The results showed that the compressive strength and workability of self-compacting concrete were increased by increasing the particle size of aggregate, optimizing gradation, choosing proper sand percentage and increasing shape index in a certain range.

scholarly journals Experimental Studies of Scale Effect on the Shear Strength of Coarse-Grained Soil

2022 ◽  
Vol 12 (1) ◽  
pp. 447
Author(s):  
Shuya Li ◽  
Tiancheng Wang ◽  
Hao Wang ◽  
Mingjie Jiang ◽  
Jungao Zhu
Keyword(s):  
Particle Size ◽  
Shear Strength ◽  
Internal Friction ◽  
Scale Effect ◽  
Friction Angle ◽  
Coarse Grained ◽  
Test Results ◽  
Maximum Particle Size ◽  
Maximum Particle ◽  
Coarse Grained Soil

Shear strength is an essential index for the evaluation of soil stability. Test results of the shear strength of scaled coarse-grained soil (CGS for short) are usually not able to accurately reflect the actual properties and behaviors of in situ CGS due to the scale effect. Therefore, this study focuses on the influence of the scale effect on the shear strength of scaled CGS, which has an important theoretical significance and application for the strength estimation of CGS in high earth-rock dam engineering. According to previous studies, the main cause of the scale effect for scaled CGS is the variation of the gradation structure as well as the maximum particle size (dmax), in which the gradation structure as a characteristic parameter can be expressed by the gradation area (S). A total of 24 groups of test soil samples with different gradations were designed by changing the maximum particle size dmax and gradation area S. Direct shear tests were conducted in this study to quantitatively explore the effect of the gradation structure and the maximum particle size on the shear strength of CGS. Test results suggest that the shear strength indexes (i.e., the cohesion and internal friction angle) of CGS present an increasing trend with the improvement of the maximum particle size dmax, and thus a logarithmic function relationship among c, φ, and dmax is presented. Both cohesion (c) and internal friction angle (φ) are negatively related to the gradation area (S) in most cases. As a result, an empirical relationship between c, φ, and S is established based on the test results. Furthermore, a new prediction model of shear strength of CGS considering the scale effect is proposed, and the accuracy of this model is verified through the test results provided by relevant literature. Finally, the applicability of this model to different types of CGS is discussed.

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