Recycling of a Concrete Pavement after over 80 Years in Service

This article presents the results of fatigue testing and assessment of the mechanical and physical properties of the concrete pavement of the A6 motorway, which was put in service in 1938. After 82 years of operation under heavy traffic loading conditions, the pavement was fully recycled by crushing of the existing concrete and reuse of the reclaimed material in the new courses of pavement placed as part of the motorway renewal project. The main objective of this research was to determine the properties of the tested concrete, including compressive strength, water absorption and freeze-thaw resistance after 150 cycles of alternate freezing and thawing. The resistance of the concrete to the action of de-icing products was also checked. The article also presents the results of petrographic analysis of the aggregates. Additionally, concrete sampled from the pavement was evaluated for freeze-thaw resistance in relation to the determined porosity characteristics. The tested concrete, which was subjected to over 80 years of traffic loading on the A6 motorway, was found to meet the highest requirements as currently applied for the extra heavy-duty pavements. With a compressive strength value in excess of 50 MPa, the tested concrete can be rated at least CC40, according to EN 13877-2:2013-08. The samples were found to satisfy the freeze-thaw resistance requirements of an F150 rating. The air void analysis showed that the analyzed concrete contained 1.6% of micropores, i.e., air voids smaller than 300 μm (A300). The spacing factor, in turn, was below 0.200 mm (L = 0.185 mm). The example of the A6 motorway renewal project served to demonstrate that reclaimed concrete aggregate, obtained by crushing the entire pavement, can be used for production of the new pavement courses.

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Effects of Cyclic Freeze–Thaw on the Steel Bar Reinforced New-To-Old Concrete Interface

Molecules ◽

10.3390/molecules25051251 ◽

2020 ◽

Vol 25 (5) ◽

pp. 1251

Author(s):

Tao Luo ◽

Chi Zhang ◽

Xiangtian Xu ◽

Yanjun Shen ◽

Hailiang Jia ◽

...

Keyword(s):

Compressive Strength ◽

Shear Strength ◽

Concrete Structures ◽

Freezing Temperature ◽

Frost Damage ◽

Freezing And Thawing ◽

Shear Properties ◽

Freeze Thaw ◽

Steel Bar ◽

Concrete Interface

Frost damage of concrete has significant effects on the safety and durability of concrete structures in cold regions, and the concrete structures after repair and reinforcement are still threatened by cyclic freezing and thawing. In this study, the new-to-old concrete interface was reinforced by steel bar. The shear strength of the new-to-old concrete interface was tested after the new-to-old combination was subjected to cyclic freeze–thaw. The effects of the diameter of the steel bar, the compressive strength of new concrete, the number of freeze–thaw cycles and the freezing temperatures on the shear properties of new-to-old concrete interface were studied. The results showed that, in a certain range, the shear strength of the interface was proportional to the diameter of the steel bar and the strength of the new concrete. Meanwhile, the shear strength of the reinforced interface decreased with the decreasing of the freezing temperature and the increasing of the number of freeze–thaw cycles.

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Effect of freeze–thaw cycles on the resilient moduli and unconfined compressive strength of rubberized recycled concrete aggregate as pavement base/subbase

Transportation Geotechnics ◽

10.1016/j.trgeo.2020.100477 ◽

2021 ◽

Vol 27 ◽

pp. 100477

Author(s):

Mohammad Saberian ◽

Jie Li

Keyword(s):

Compressive Strength ◽

Unconfined Compressive Strength ◽

Recycled Concrete ◽

Concrete Aggregate ◽

Recycled Concrete Aggregate ◽

Freeze Thaw ◽

Pavement Base

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Performance Evaluation of the Polyurethane-Based Composites Prepared with Recycled Polymer Concrete Aggregate

Materials ◽

10.3390/ma13030616 ◽

2020 ◽

Vol 13 (3) ◽

pp. 616

Author(s):

Wenbo Ma ◽

Zenggang Zhao ◽

Shuaicheng Guo ◽

Yanbing Zhao ◽

Zhiren Wu ◽

...

Keyword(s):

Compressive Strength ◽

Mechanical Performance ◽

Strength Loss ◽

Polymer Concrete ◽

Concrete Aggregate ◽

Test Results ◽

Freeze Thaw ◽

Polyurethane Composites ◽

Durability Performance ◽

Recycled Polymer

Currently the investigation on recycled cement concrete aggregate has been widely conducted, while the understanding of the recycled polymer concrete aggregate is still limited. This study aims to fill this knowledge gap through the experimental investigation on mechanical and durability performance. Specifically, the remolded polyurethane stabilized Pisha sandstone was collected as the recycled polymer concrete aggregate. The remolded Pisha sandstone was then applied to re-prepare the polyurethane-based composites. After that, the mechanical performance of the prepared composites was first examined with unconfined and triaxial compressive tests. The results indicated that the Pisha sandstone reduces the composite’s compressive strength. The reduction is caused by the remained polyurethane material on the surface of the remolded aggregate, which reduces its bond strength with the new polyurethane material. Aiming at this issue, this study applied the ethylene-vinyl acetate (EVA) to enhance the bond performance between the polyurethane and remolded sandstone. The test results indicated both the unconfined and triaxle compressive strength of the polyurethane composites were enhanced with the added EVA content. Furthermore, the durability performance of the EVA-modified composites were examined through freeze-thaw and wet-dry cycle tests. The test results indicated the EVA could enhance the polyurethane composites’ resistance to both wet-dry and freeze-thaw cycles. Overall, the modification with EVA can compensate for the strength loss of polyurethane composites because of the applied remolded aggregate and enhance its sustainability.

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Structural Performance of Permeable Interlocking Concrete Pavement under Heavy Traffic Loading

New Frontiers in Road and Airport Engineering ◽

10.1061/9780784414255.017 ◽

2015 ◽

Cited By ~ 1

Author(s):

H. Li ◽

R. Wu ◽

D. Jones ◽

J. Harvey ◽

D. R. Smith

Keyword(s):

Heavy Traffic ◽

Concrete Pavement ◽

Structural Performance ◽

Traffic Loading ◽

Permeable Interlocking Concrete Pavement

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Functional Properties of a Pitch-Based Carbon Fiber–Mortar Composite as a Thin Overlay for Concrete Pavement

Materials ◽

10.3390/ma12172753 ◽

2019 ◽

Vol 12 (17) ◽

pp. 2753

Author(s):

Jun Seok Lee ◽

Inkyu Rhee

Keyword(s):

Thermal Conductivity ◽

Compressive Strength ◽

Carbon Fiber ◽

Fiber Strength ◽

Low Cost ◽

Cementitious Materials ◽

Concrete Pavement ◽

Control Specimen ◽

Freezing And Thawing ◽

Adhesion Performance

This experimental study investigated the utility of a pitch-based carbon fiber–mortar composite, which could replace polyacrylonitrile carbon fiber, as a thin overlay for concrete pavement. The objective was to explore the utility of the low-cost carbon fiber, which was produced via a melt-blown method, i.e., blowing at high pressure after melting the pitch residue following crude oil purification. The mechanical properties, durability, and thermal properties of the pitch-based carbon fiber were explored to maximize strength, durability, functionality, and economy by using micro-sized fibers that are closer in size to the constituents of cementitious materials. Melt-blown pitch-based carbon fiber has low individual fiber strength but generally excellent thermal conductivity. Thermal conductivity tests were conducted on mortar panels (560 mm × 560 mm; thickness = 25, 40 or 60 mm) containing 0, 0.4, 0.5 or 0.6 wt % pitch-based carbon fiber. The absolute thermal conductivity tended to improve with higher wt % of pitch-based carbon fiber, in the range of 9~11 W/°C. However, thermal conductivity tended to be lower under the 0.6 wt % condition, possibly due to the effect of dispersion. Compressive strength degradation was tested over 350 cycles of freezing and thawing: the strength of the 0.4, 0.5 or 0.6 wt % samples was 91, 89, and 82%, respectively, relative to the control specimen (0 wt %). Thus, all specimens had a compressive strength of 80% or more after 350 cycles compared to the control specimen. To test the adhesion performance for new thin overlays and old concrete surfaces, concrete cylinders (100 × 200 mm; thickness = 10 mm) were cut at an angle of 46 degrees, and the pitch-based carbon fiber-mortar composite was used to bond the various sections. The bond strength of the test specimens was more than twice that of the reference specimen.

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Effect of Freeze-Thaw Cycles on Mechanical Behaviors of Ceramsite Concrete under Impact Loading

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.784.508 ◽

2015 ◽

Vol 784 ◽

pp. 508-513 ◽

Cited By ~ 2

Author(s):

Jiang Ying Chen ◽

Xin Qiu ◽

Guan Yin Shi ◽

Bo Fei Chen ◽

Xu Sheng Huang

Keyword(s):

Compressive Strength ◽

Impact Loading ◽

Damage Evolution ◽

Volume Fraction ◽

Mechanical Behaviors ◽

Hopkinson Pressure Bar ◽

Freezing And Thawing ◽

Freeze Thaw ◽

Dynamic Compressive Strength ◽

Pressure Bar

In order to study the influence of freezing and thawing on the dynamic behavior of ceramsite concrete, specimens with four kinds of ceramsite volume fraction including 0%, 15%, 30% and 45% which subjected to 0, 10, 20, 30 and 40 cycles of freezing and thawing respectively, are tested by means of the Spilt Hopkinson Pressure Bar technique. The experimental results showed that under dynamic loading the ceramisite concrete was weakened with increasing of the number of freeze-thaw cycles. Changes of dynamic compressive strength and damage evolution affected by freeze-thaw cycling and volume fraction of ceramsite are discussed in the paper.

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Estimating uniaxial compressive strength of carbonate building stones based on some intact stone properties after deterioration by freeze–thaw

Environmental Earth Sciences ◽

10.1007/s12665-021-09658-8 ◽

2021 ◽

Vol 80 (9) ◽

Author(s):

Vahid Amirkiyaei ◽

Ebrahim Ghasemi ◽

Lohrasb Faramarzi

Keyword(s):

Compressive Strength ◽

Uniaxial Compressive Strength ◽

Building Stones ◽

Freeze Thaw

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Strength and Microscopic Damage Mechanism of Yellow Sandstone with Holes under Freezing and Thawing

Advances in Civil Engineering ◽

10.1155/2020/5921901 ◽

2020 ◽

Vol 2020 ◽

pp. 1-13 ◽

Cited By ~ 1

Author(s):

Huren Rong ◽

Jingyu Gu ◽

Miren Rong ◽

Hong Liu ◽

Jiayao Zhang ◽

...

Keyword(s):

Mechanical Properties ◽

Pore Size ◽

Power Function ◽

Damage Mechanism ◽

Uniaxial Compression Test ◽

Freezing And Thawing ◽

Freeze Thaw ◽

Thaw Cycle ◽

Freeze Thaw Cycle ◽

Microscopic Damage

In order to study the damage characteristics of the yellow sandstone containing pores under the freeze-thaw cycle, the uniaxial compression test of saturated water-stained yellow sandstones with different freeze-thaw cycles was carried out by rock servo press, the microstructure was qualitatively analyzed by Zeiss 508 stereo microscope, and the microdamage mechanism was quantitatively studied by using specific surface area and pore size analyzer. The mechanism of weakening mechanical properties of single-hole yellow sandstone was expounded from the perspective of microstructure. The results show the following. (1) The number of freeze-thaw cycles and single-pore diameter have significant effects on the strength and elastic modulus of the yellow sandstone; the more the freeze-thaw cycles and the larger the pore size, the lower the strength of the yellow sandstone. (2) The damage modes of the yellow sandstone containing pores under the freeze-thaw cycle are divided into five types, and the yellow sandstone with pores is divided into two areas: the periphery of the hole and the distance from the hole; as the number of freeze-thaw cycles increases, different regions show different microscopic damage patterns. (3) The damage degree of yellow sandstone is different with freeze-thaw cycle and pore size. Freeze-thaw not only affects the mechanical properties of yellow sandstone but also accelerates the damage process of pores. (4) The damage of the yellow sandstone by freeze-thaw is logarithmic function, and the damage of the yellow sandstone is a power function. The damage equation of the yellow sandstone with pores under the freezing and thawing is a log-power function nonlinear change law and presents a good correlation.

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Review of Strength and Failure Criteria for Concrete After Freeze-Thaw Damage

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.253-255.456 ◽

2012 ◽

Vol 253-255 ◽

pp. 456-461

Author(s):

Yan Fu Qin ◽

Bin Tian ◽

Gang Xu ◽

Xiao Chun Lu

Keyword(s):

Normal State ◽

Concrete Strength ◽

Failure Criteria ◽

Concrete Durability ◽

Freezing And Thawing ◽

Normal Concrete ◽

Strength Criteria ◽

Freeze Thaw ◽

Ordinary Concrete ◽

Concrete Failure

Frost resistance research is one of the important subject of concrete durability, however strength criteria is an important part of the study of mechanical behavior of concrete. So far, about concrete failure criteria are almost for normal concrete, which the domestic and overseas scholars have comparative detailed research in every respect to it, and to freeze-thaw damage of concrete but few research. Based on the summary of the existing ordinary concrete strength and failure criteria in normal state and after freeze-thaw damage，this paper have a brief comment of failure criteria on concrete after freeze-thaw damage. For later research about concrete strength and failure criteria under freezing and thawing cycle provide the reference.

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