Synergistic Improvement of Strength Characteristics in Recycled Aggregates Using Nano-Clay and Polypropylene Fiber

In order to study the improvement effect of nano-clay and polypropylene fiber on the mechanical properties of recycled aggregates, unconfined compression tests and triaxial shear tests were conducted. The experimental results show that adding polypropylene fibers to recycled aggregates increases the...

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Main Authors: Tieyong Zhao, Chenjun Wang, De Zhang, Yanfei Yu, Jiale Luo, Cuihong Li
Format: Article
Language:English
Published: MDPI AG 2024-01-01
Series:Polymers
Subjects:
Online Access:https://www.mdpi.com/2073-4360/16/3/374
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author Tieyong Zhao
Chenjun Wang
De Zhang
Yanfei Yu
Jiale Luo
Cuihong Li
author_facet Tieyong Zhao
Chenjun Wang
De Zhang
Yanfei Yu
Jiale Luo
Cuihong Li
author_sort Tieyong Zhao
collection DOAJ
description In order to study the improvement effect of nano-clay and polypropylene fiber on the mechanical properties of recycled aggregates, unconfined compression tests and triaxial shear tests were conducted. The experimental results show that adding polypropylene fibers to recycled aggregates increases the unconfined compressive strength by 27% and significantly improves ductility. We added 6% nano-clay to fiber-reinforced recycled aggregates, which increased the unconfined compressive strength of the recycled aggregates by 49% and the residual stress by 146%. However, the ductility decreased. Under low confining pressures, with the addition of nano-clay, the peak deviatoric stress strength of the fiber-reinforced recycled aggregates first decreased and then increased. When the nano-clay content was 8%, this reached a maximum value. However, under high confining pressures, the recycled aggregate particles were tightly interlocked, so that the improvement effect of the fiber and nano-clay was not obvious. As more nano-clay was added, the friction angle of the fiber-reinforced recycled aggregates decreased, while the cohesion increased. When the content of nano-clay was 8%, the cohesive force increased by 110%. The results of this research indicate that adding both polypropylene fibers and nano-clay to recycled aggregates has a better improvement effect on their strength characteristics than adding only polypropylene fibers. This study can provide a reference for improving the mechanical properties of recycled aggregates and the use of roadbeds.
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spelling doaj.art-0a1c3b97ac074b8f810ec20b6a29dd2b2024-02-09T15:20:52ZengMDPI AGPolymers2073-43602024-01-0116337410.3390/polym16030374Synergistic Improvement of Strength Characteristics in Recycled Aggregates Using Nano-Clay and Polypropylene FiberTieyong Zhao0Chenjun Wang1De Zhang2Yanfei Yu3Jiale Luo4Cuihong Li5School of Civil Engineering, Shaoxing University, Shaoxing 312000, ChinaSchool of Civil Engineering, Shaoxing University, Shaoxing 312000, ChinaShanghai Road and Bridge Group Co., Ltd., Shanghai 200000, ChinaSchool of Civil Engineering, Shaoxing University, Shaoxing 312000, ChinaSchool of Civil Engineering, Shaoxing University, Shaoxing 312000, ChinaSchool of Civil Engineering, Shaoxing University, Shaoxing 312000, ChinaIn order to study the improvement effect of nano-clay and polypropylene fiber on the mechanical properties of recycled aggregates, unconfined compression tests and triaxial shear tests were conducted. The experimental results show that adding polypropylene fibers to recycled aggregates increases the unconfined compressive strength by 27% and significantly improves ductility. We added 6% nano-clay to fiber-reinforced recycled aggregates, which increased the unconfined compressive strength of the recycled aggregates by 49% and the residual stress by 146%. However, the ductility decreased. Under low confining pressures, with the addition of nano-clay, the peak deviatoric stress strength of the fiber-reinforced recycled aggregates first decreased and then increased. When the nano-clay content was 8%, this reached a maximum value. However, under high confining pressures, the recycled aggregate particles were tightly interlocked, so that the improvement effect of the fiber and nano-clay was not obvious. As more nano-clay was added, the friction angle of the fiber-reinforced recycled aggregates decreased, while the cohesion increased. When the content of nano-clay was 8%, the cohesive force increased by 110%. The results of this research indicate that adding both polypropylene fibers and nano-clay to recycled aggregates has a better improvement effect on their strength characteristics than adding only polypropylene fibers. This study can provide a reference for improving the mechanical properties of recycled aggregates and the use of roadbeds.https://www.mdpi.com/2073-4360/16/3/374recycled aggregatenano-claypolypropylene fiberunconfined compression strengthdeviatoric stress
spellingShingle Tieyong Zhao
Chenjun Wang
De Zhang
Yanfei Yu
Jiale Luo
Cuihong Li
Synergistic Improvement of Strength Characteristics in Recycled Aggregates Using Nano-Clay and Polypropylene Fiber
Polymers
recycled aggregate
nano-clay
polypropylene fiber
unconfined compression strength
deviatoric stress
title Synergistic Improvement of Strength Characteristics in Recycled Aggregates Using Nano-Clay and Polypropylene Fiber
title_full Synergistic Improvement of Strength Characteristics in Recycled Aggregates Using Nano-Clay and Polypropylene Fiber
title_fullStr Synergistic Improvement of Strength Characteristics in Recycled Aggregates Using Nano-Clay and Polypropylene Fiber
title_full_unstemmed Synergistic Improvement of Strength Characteristics in Recycled Aggregates Using Nano-Clay and Polypropylene Fiber
title_short Synergistic Improvement of Strength Characteristics in Recycled Aggregates Using Nano-Clay and Polypropylene Fiber
title_sort synergistic improvement of strength characteristics in recycled aggregates using nano clay and polypropylene fiber
topic recycled aggregate
nano-clay
polypropylene fiber
unconfined compression strength
deviatoric stress
url https://www.mdpi.com/2073-4360/16/3/374
work_keys_str_mv AT tieyongzhao synergisticimprovementofstrengthcharacteristicsinrecycledaggregatesusingnanoclayandpolypropylenefiber
AT chenjunwang synergisticimprovementofstrengthcharacteristicsinrecycledaggregatesusingnanoclayandpolypropylenefiber
AT dezhang synergisticimprovementofstrengthcharacteristicsinrecycledaggregatesusingnanoclayandpolypropylenefiber
AT yanfeiyu synergisticimprovementofstrengthcharacteristicsinrecycledaggregatesusingnanoclayandpolypropylenefiber
AT jialeluo synergisticimprovementofstrengthcharacteristicsinrecycledaggregatesusingnanoclayandpolypropylenefiber
AT cuihongli synergisticimprovementofstrengthcharacteristicsinrecycledaggregatesusingnanoclayandpolypropylenefiber