Effects of Coarse Aggregate Form, Angularity, and Surface Texture on Concrete Mechanical Performance

The resilient modulus measured in the indirect tensile mode according to ASTM D 4123 reflects effectively the elastic properties of asphalt mixtures under repeated load. The coarse aggregate morphology quantified by angularity and surface texture properties affects resilient modulus of asphalt mixes; however, the relationship is not yet well understood because of the lack of quantitative measurement of coarse aggregate morphology. This paper presents findings of a laboratory study aimed at investigating the effects of the material properties of the major component on the resilient modulus of asphalt mixes, with the coarse aggregate morphology considered as the principal factor. With modulus tests performed at a temperature of 25°C, using coarse aggregates with more irregular morphologies substantially improved the resilient modulus of asphalt mixtures. An imaging-based angularity index was found to be more closely related to the resilient modulus than an imaging-based surface texture index, as indicated by a higher value of the correlation coefficient. The stiffness of the asphalt binder also had a strong influence on modulus. When the resilient modulus data were grouped on the basis of binder stiffnesses, the agreement between the coarse aggregate morphology and the resilient modulus was significantly improved in each group. Although the changes in aggregate gradation did not significantly affect the relationship between the coarse aggregate morphology and the resilient modulus, decreasing the nominal maximum aggregate size from 19 mm to 9.5 mm indicated an increasing positive influence of aggregate morphology on the resilient modulus of asphalt mixes.

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High Definition Metrology-Based Quality Improvement of Surface Texture in Face Milling of Workpieces with Discontinuous Surfaces

Journal of Manufacturing Science and Engineering ◽

10.1115/1.4051883 ◽

2021 ◽

pp. 1-38

Author(s):

Guilong Li ◽

Shichang Du ◽

Bo Wang ◽

Jun Lv ◽

Yafei Deng

Keyword(s):

Quality Improvement ◽

Surface Texture ◽

Mechanical Performance ◽

Processing Parameters ◽

Milling Process ◽

Face Milling ◽

Measurement Instruments ◽

High Definition ◽

Tool Marks

Abstract In face milling process, the quality of surface texture is vital for mechanical performance of workpieces. The quality of surface texture, especially for waviness, is directly affected by tool marks, a commonly observed phenomenon in face milling. However, appropriate approaches for evaluation and modeling of tool marks are absent to date. Limited to the resolution as well as the efficiency of conventional measurement instruments, the height data of tool marks is hard to be entirely obtained, leading to valuable information omission. Besides, most existing models of tool marks are established for general workpieces with regular geometry and continuous surfaces. Since the cutter-workpiece engagement mode has a significant impact on the generation of tool marks, current models could be inaccurate or invalid when dealing with workpieces with discontinuous surfaces. To overcome this shortage, a novel approach is proposed in this paper, aimed at quality improvement of surface texture in face milling of workpieces with discontinuous surfaces. Firstly, the evaluation indexes for tool marks are defined based on the recently developed high definition metrology (HDM). Secondly, the physical modeling of tool marks is presented, taking the face milling mechanism into account. Thirdly, the physical-informed optimization model is developed to search for the optimal processing parameters for surface quality improvement. At last, the effectiveness of the proposed approach is verified by a face milling experiment on the engine blocks.

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Influence of coarse aggregate angularity on the mechanical performance of cement-based materials

Construction and Building Materials ◽

10.1016/j.conbuildmat.2019.01.135 ◽

2019 ◽

Vol 204 ◽

pp. 184-192 ◽

Cited By ~ 9

Author(s):

Seung Jae Lee ◽

Chang Hoon Lee ◽

Moochul Shin ◽

Sumana Bhattacharya ◽

Yu Feng Su

Keyword(s):

Coarse Aggregate ◽

Mechanical Performance ◽

Cement Based Materials

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The Effect of Mixing Natural Aggregates with Artificial Aggregates on Marshall Parameters

Jurnal Inotera ◽

10.31572/inotera.vol6.iss1.2021.id135 ◽

2021 ◽

Vol 6 (1) ◽

pp. 10-19

Author(s):

Muhammad Riski ◽

Febrina Dian Kurniasari ◽

Bunyamin

Keyword(s):

Surface Texture ◽

Coarse Aggregate ◽

National Standard ◽

Best Value ◽

City District ◽

Asphalt Content ◽

Natural Aggregates ◽

Excellent Adhesion ◽

The Stability ◽

The Cost

In general, aggregates consist of Natural Aggregates (NA) and Artificial Aggregates (AA). Artificial aggregates, such as Crushed Stone (CS), are aggregates produced through the crusher industry which has a rough and angular surface so that it has excellent adhesion to asphalt. Meanwhile, NA is an aggregate produced from a river which has a smooth and large hollow surface texture. The cost for AA is very expensive when compared to NA, so it is necessary to experiment with mixing NA and AA to minimize the use of AA. NA are obtained from Sungai Jalin, Jantho City District, Aceh Besar District. The method used refers to the specification of Bina Marga 2010 Revision four (2018) and the Indonesian National Standard (SNI). The purpose of this study was to see the effect of the combination of NA and AA as a substitute for coarse aggregate on the AC-WC concrete asphalt layer. The specimens used were 66 specimens with substitution of NA and AA into the asphalt layer were 0% NA: 100% AA, 25% NA: 75% AA, 50% NA: 50% AA, 75% NA: 25% AA, 100% NA : 0% AA. Based on the research results, the best value for the optimum marshall parameter is the substitution of 25% AA: 75% BP at asphalt content of 5.00%, the stability value is 1492.37kg with a VIM value of 3.69%, VMA 16.17%, VFA 77.88% and MQ 573.87kg / mm which have met the requirements of the 2010 Revision four (2018) Bina Marga specification.

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Concrete with Partial Substitution of Waste Glass and Recycled Concrete Aggregate

Materials ◽

10.3390/ma15020430 ◽

2022 ◽

Vol 15 (2) ◽

pp. 430

Author(s):

Jawad Ahmad ◽

Rebeca Martínez-García ◽

Jesús de-Prado-Gil ◽

Kashif Irshad ◽

Mohammed A. El-Shorbagy ◽

...

Keyword(s):

Performance Test ◽

Coarse Aggregate ◽

Mechanical Performance ◽

Negative Impact ◽

Strength Properties ◽

Waste Glass ◽

Recycled Concrete ◽

Partial Substitution ◽

Concrete Aggregate ◽

Recycled Concrete Aggregate

The current practice of concrete is thought to be unsuitable because it consumes large amounts of cement, sand, and aggregate, which causes depletion of natural resources. In this study, a step towards sustainable concrete was made by utilizing recycled concrete aggregate (RCA) as a coarse aggregate. However, researchers show that RCA causes a decrease in the performance of concrete due to porous nature. In this study, waste glass (WG) was used as a filler material that filled the voids between RCA to offset its negative impact on concrete performance. The substitution ratio of WG was 10, 20, or 30% by weight of cement, and RCA was 20, 40, and 60% by weight of coarse aggregate. The slump cone test was used to assess the fresh property, while compressive, split tensile, and punching strength were used to assess the mechanical performance. Test results indicated that the workability of concrete decreased with substitution of WG and RCA while mechanical performance improved up to a certain limit and then decreased due to lack of workability. Furthermore, a statical tool response surface methodology was used to predict various strength properties and optimization of RCA and WG.

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Comparison and Evaluation of Tests for Coarse Aggregate Particle Shape, Angularity, and Surface Texture

Journal of Testing and Evaluation ◽

10.1520/jte12078j ◽

2000 ◽

Vol 28 (2) ◽

pp. 77 ◽

Cited By ~ 11

Author(s):

DR Petersen ◽

RE Link ◽

MS Hossain ◽

F Parker ◽

PS Kandhal

Keyword(s):

Surface Texture ◽

Particle Shape ◽

Coarse Aggregate ◽

Aggregate Particle

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Effects of surface texture and its mineral composition on interfacial behavior between asphalt binder and coarse aggregate

Construction and Building Materials ◽

10.1016/j.conbuildmat.2020.120869 ◽

2020 ◽

Vol 262 ◽

pp. 120869

Author(s):

Ponan Feng ◽

Hainian Wang ◽

Heyang Ding ◽

Jinkun Xiao ◽

Marwa Hassan

Keyword(s):

Mineral Composition ◽

Surface Texture ◽

Coarse Aggregate ◽

Asphalt Binder ◽

Interfacial Behavior

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Feasibility of Developing Sustainable Concrete Using Environmentally Friendly Coarse Aggregate

Applied Sciences ◽

10.3390/app10155207 ◽

2020 ◽

Vol 10 (15) ◽

pp. 5207

Author(s):

Chamila Gunasekara ◽

Charitha Seneviratne ◽

David W. Law ◽

Sujeeva Setunge

Keyword(s):

Mechanical Properties ◽

Compressive Strength ◽

Coarse Aggregate ◽

Mechanical Performance ◽

Drying Shrinkage ◽

Strength Development ◽

Design Strength ◽

Coarse Aggregates ◽

Increasing Demand ◽

Quality Material

Quarry aggregate reserves are depleting rapidly within Australia and the rest of the world due to an increasing demand for aggregates driven by expansion in construction. The annual production of premix concrete in Australia is approximately 30 million cubic meters, while 3–5% of concrete delivered to site remains unused and is disposed of in landfill or crushing plants. The production of coarse aggregates using this waste concrete is potentially a sustainable approach to reduce environmental and economic impact. A testing program has been conducted to investigate mechanical performance and permeation characteristics of concrete produced using a novel manufactured coarse aggregate recycled directly from fresh premix concrete. The recycled coarse aggregate (RCA) concrete satisfied the specified 28-day design strength of 25 MPa and 40 MPa at 28 days and a mean compressive strength of 60 MPa at 90 days. Aggregate grading was observed to determine strength development, while low water absorption, low drying shrinkage, and higher packing density indicate that the RCA concrete is a high-quality material with a dense pore structure. The rough fracture surface of the aggregate increased the bond between C-S-H gel matrix and RCA at the interfacial transition zone. Furthermore, a good correlation was observed between compressive strength and all other mechanical properties displayed by the quarried aggregate concrete. The application of design equations as stated in Australian standards were observed to provide a conservative design for RCA concrete structures based on the mechanical properties.

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Application of Coal Gangue as a Coarse Aggregate in Green Concrete Production: A Review

Materials ◽

10.3390/ma14226803 ◽

2021 ◽

Vol 14 (22) ◽

pp. 6803

Author(s):

Shan Gao ◽

Sumei Zhang ◽

Lanhui Guo

Keyword(s):

Coarse Aggregate ◽

Mechanical Performance ◽

Chemical Properties ◽

Coal Gangue ◽

Replacement Ratio ◽

Green Concrete ◽

Concrete Members ◽

Concrete Production ◽

Absorption Law ◽

Physical And Chemical

Among the techniques for converting stacked coal gangue to reusable material, one of the most effective ways is to use coal gangue as a coarse aggregate in green concrete productions. The physical and chemical properties of rock and spontaneous-combustion coal gangue are generally suitable for being used as a coarse aggregate in green concrete. Coal gangue concrete is not recommended to be used in subsurface structures, as its water absorption law would be changed under a large replacement ratio. The mechanical performance of coal gangue concrete is degraded by raising the replacement ratio. Over-low and -high concrete grades are not suggested to be used as coal gangue aggregate, unless extra admixtures or specific methods are used. The influence of coal gangue on the durability of coal gangue concrete is remarkable, resulting from the porous structure of coal gangue that provides more transmission channels for air and liquid in concrete, but is beneficial for thermal insulation. The usage of coal gangue in structural concrete members is still limited. The mechanical behavior of some structural members using coal gangue concrete has been reported. Among them, concrete filled steel tubes are a preferable configuration for using coal gangue concrete, regarding both the mechanical and durability performance.

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