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Stick of the deep-sea sediment on the surface of the mining machine can deteriorate its working efficiency. To resolve this issue, this study aims to reduce the adhesion force along the soil-metal interface by adjusting the roughness of the metal surface. During the experimental study, six types of Titanium samples with different surface roughness were first prepared through surface polishing. Then the adhesion force between the marine clay agglomerate and the Titanium surface was measured with Atomic Force Microscopy (AFM). The measured results indicated the adhesion force would first decrease and then increase with the surface roughness. The contact analysis based on Finite Element Analysis was then conducted to investigate the related mechanism. The simulation results indicated changed contact area with the surface roughness can partially explain the existence of the critical roughness with minimum adhesion force. This study can provide a substitutional protocol to reduce the adhesion force between the metal surface of the engineering machine and the surrounding adhesive clay.
Wenbo Ma; Jiaping Li; Qing Cai; Wei Zhu; Caiqian Yang; Shuaicheng Guo. Influence of surface roughness on the adhesion force between the titanium plate and deep-sea sediment. Marine Georesources & Geotechnology 2020, 1 -9.
AMA StyleWenbo Ma, Jiaping Li, Qing Cai, Wei Zhu, Caiqian Yang, Shuaicheng Guo. Influence of surface roughness on the adhesion force between the titanium plate and deep-sea sediment. Marine Georesources & Geotechnology. 2020; ():1-9.
Chicago/Turabian StyleWenbo Ma; Jiaping Li; Qing Cai; Wei Zhu; Caiqian Yang; Shuaicheng Guo. 2020. "Influence of surface roughness on the adhesion force between the titanium plate and deep-sea sediment." Marine Georesources & Geotechnology , no. : 1-9.
This study intends to evaluate the feasibility of the use of recycled cathode ray tube (CRT) glass in water-foamed asphalt mixtures used in low volume roads. In the asphalt mixture samples, 21.5% (wt.) aggregates were replaced by the recycled CRT glass to evaluate the mechanical performance and leaching potential. First, the leaching test was used to characterize the leaching potential of the CRT mixes since there is high lead content in CRT glass, which may be harmful to the groundwater if the hazardous lead leaches from the CRT mixes. Second, the high-temperature rutting and the low-temperature cracking performance of the asphalt mixtures were measured via the Hamburg Wheel Tracking Test (HWTT) and the Disk-Shape Compact Tension (DCT) test, respectively. In addition, the Moisture-Induced Stress Tester (MIST) was used to simulate the pore pressure generated in a wet pavement under moving traffic loading. The experimental results showed that, although the measured lead leaching of the pure CRT glass particles was higher than the regulatory level of 5 mg/L, the coated asphalt could effectively insulate the contact between CRT glass and the external environment, resolving the leaching issues. In summary, from the view of the mechanical performance of the water-foamed asphalt mixtures containing recycled CRT glass, the performance is acceptable in various temperatures when used in low volume roads. Recycling CRT glass in asphalt mixture should be carried out with extreme caution because if not done correctly, the potential leaching may eliminate the benefits of recycling unwanted waste materials.
Lingyun You; Dongzhao Jin; Shuaicheng Guo; Jiaqing Wang; Qingli Dai; Zhanping You. Leaching evaluation and performance assessments of asphalt mixtures with recycled cathode ray tube glass: A preliminary study. Journal of Cleaner Production 2020, 279, 123716 .
AMA StyleLingyun You, Dongzhao Jin, Shuaicheng Guo, Jiaqing Wang, Qingli Dai, Zhanping You. Leaching evaluation and performance assessments of asphalt mixtures with recycled cathode ray tube glass: A preliminary study. Journal of Cleaner Production. 2020; 279 ():123716.
Chicago/Turabian StyleLingyun You; Dongzhao Jin; Shuaicheng Guo; Jiaqing Wang; Qingli Dai; Zhanping You. 2020. "Leaching evaluation and performance assessments of asphalt mixtures with recycled cathode ray tube glass: A preliminary study." Journal of Cleaner Production 279, no. : 123716.
The self-compacting concrete (SCC) with the replacement of recycled rubber aggregates is limited for the field application due to high-performance requirements. The steel fiber was introduced to the rubberized SCC (RSCC) to enhance its performance and promote its application. The fresh and mechanical properties and durability performance of steel fiber-reinforced rubber self-compacting concrete (SRSCC) were evaluated. The SRSCC samples were prepared with replaced rubber aggregate based on fine aggregate volume percentages of 10%, 15%, and 25% and a consistent steel fiber ratio of 0.2%. The plain SCC and rubberized SCC samples were also produced for comparison. The fresh performance was evaluated with slump flow, J-ring flow, V-funnel, and U-box tests. The results showed that both filling and passing ability could be affected by the added steel fiber and rubber aggregate. However, the SRSCC could still meet most of the recommended criteria for passing and filling abilities when the rubber content is lower than 25%. Regarding the hardened properties, the compressive strength was reduced in rubber SCC samples with increased rubber contents by comparing with the control SCC samples. Nevertheless, SRSCC samples with 10% rubbers have higher splitting tensile strength than RSCC and plain SCC. Also, the SRSCC specimens showed excellent freeze-thaw resistance after 600 F-T cycles. The relative dynamic modulus of elasticity slightly increased without any dimensional expansion in SRSCC samples. In summary, the proposed SRSCC can meet required flowability, filling and passing abilities along with good mechanical and freeze-thaw performance. This study will provide lab test data for the applications of recycling waste tire aggregates in steel fiber-reinforced SCC.
Jiaqing Wang; Qingli Dai; Ruizhe Si; Yunxiang Ma; Shuaicheng Guo. Fresh and mechanical performance and freeze-thaw durability of steel fiber-reinforced rubber self-compacting concrete (SRSCC). Journal of Cleaner Production 2020, 277, 123180 .
AMA StyleJiaqing Wang, Qingli Dai, Ruizhe Si, Yunxiang Ma, Shuaicheng Guo. Fresh and mechanical performance and freeze-thaw durability of steel fiber-reinforced rubber self-compacting concrete (SRSCC). Journal of Cleaner Production. 2020; 277 ():123180.
Chicago/Turabian StyleJiaqing Wang; Qingli Dai; Ruizhe Si; Yunxiang Ma; Shuaicheng Guo. 2020. "Fresh and mechanical performance and freeze-thaw durability of steel fiber-reinforced rubber self-compacting concrete (SRSCC)." Journal of Cleaner Production 277, no. : 123180.
This objective of this study is to utilize recycled glass powder as a partial replacement precursor of the metakaolin-based geopolymer to develop a sustainable geopolymer material. Four glass powder replacement ratios were selected for the metakaolin-based geopolymer preparation (0%, 5%, 10%, and 20% by the total precursor weight). The pair distribution function (PDF) analysis indicated that a higher amount of the four-membered ring structures in the formed gel with the added glass powder. Both PDF and EDX analysis showed that the Si/Al ratio of the binder phase increased with glass powder content in the mixtures. The added glass powder can improve the workability of the geopolymer binder and prolong the setting time of the synthesized geopolymer samples. The nanoindentation test results showed that the elastic modulus of the formed gel increased with replaced 10% and 20% glass powder. In addition, the samples with 5% of glass powder achieved the highest compressive strength among tested samples. The test results indicated that the appropriate glass powder replacement can affect the geopolymerization process and modify the formed gels in the metakaolin-based geopolymer to improve the mechanical properties of the mixture. The information obtained in this study can promote the utilization of waste glass powder as a partial replacement of the precursor for the production of sustainable alkali-activated materials.
Ruizhe Si; Shuaicheng Guo; Qingli Dai; Jiaqing Wang. Atomic-structure, microstructure and mechanical properties of glass powder modified metakaolin-based geopolymer. Construction and Building Materials 2020, 254, 119303 .
AMA StyleRuizhe Si, Shuaicheng Guo, Qingli Dai, Jiaqing Wang. Atomic-structure, microstructure and mechanical properties of glass powder modified metakaolin-based geopolymer. Construction and Building Materials. 2020; 254 ():119303.
Chicago/Turabian StyleRuizhe Si; Shuaicheng Guo; Qingli Dai; Jiaqing Wang. 2020. "Atomic-structure, microstructure and mechanical properties of glass powder modified metakaolin-based geopolymer." Construction and Building Materials 254, no. : 119303.
This paper investigates the mechanical properties, nanopore structure and drying shrinkage behavior of the metakaolin-based geopolymer mixtures containing 0%–20% waste glass powder. The prepared samples were cured under ambient temperature and high temperature (60 °C), respectively. The mechanical properties of the samples can be improved by introducing the low content of glass powder (5%–10%). Microstructure and nanopore structure analysis indicated that a denser gel phase was formed in the glass powder modified geopolymer samples. The added glass powder reduced the water loss rate of the samples under drying condition, leading to a reduction of drying shrinkage at early ages. The capillary stress in the prepared geopolymer samples was analyzed based on the pore size distribution of the mixtures. The magnitude of capillary stress generated in glass powder containing samples was similar to that of geopolymers without glass powder. The improved creep modulus with added glass powder facilitated the reduction of the shrinkage of the samples at later ages. This study can facilitate the recycling of waste glass into geopolymer for sustainable construction applications.
Ruizhe Si; Qingli Dai; Shuaicheng Guo; Jiaqing Wang. Mechanical property, nanopore structure and drying shrinkage of metakaolin-based geopolymer with waste glass powder. Journal of Cleaner Production 2019, 242, 118502 .
AMA StyleRuizhe Si, Qingli Dai, Shuaicheng Guo, Jiaqing Wang. Mechanical property, nanopore structure and drying shrinkage of metakaolin-based geopolymer with waste glass powder. Journal of Cleaner Production. 2019; 242 ():118502.
Chicago/Turabian StyleRuizhe Si; Qingli Dai; Shuaicheng Guo; Jiaqing Wang. 2019. "Mechanical property, nanopore structure and drying shrinkage of metakaolin-based geopolymer with waste glass powder." Journal of Cleaner Production 242, no. : 118502.
In this study, the synergistic effect of combining macro polypropylene (PP) fiber and rubberized concrete was evaluated based on mechanical and durability performance, as well as microstructure. The specimens were prepared with two different rubber volume contents at 10% and 15%, incorporating with a consistent fiber volume fraction of 0.5%. The plain concrete specimens and specimens with only PP fiber were also produced for comparison. The mechanical test results indicated that the fracture energy of plain concrete could be enhanced with both macro PP fiber and rubber aggregates. Besides, all specimens achieved compressive strength higher than 40 Mpa, and the ultrasonic pulse velocity demonstrated the good quality of concrete specimens. The fracture morphology and ESEM imaging showed the positive function of rubber aggregates and PP fibers on the post-crack propagation. The durability performance, including drying shrinkage, ASR expansion, and frost resistance were also strengthened in macro PP fiber-reinforced rubber concrete compared with plain concrete. The macro PP fiber-reinforced rubber concrete will enlarge the post-failure flexural residual load capacity and deformation and distribute stress for multiple crack propagation, thus increasing overall fracture toughness and reducing brittleness. The sustainable applications can be further explored with the combination of macro PP fiber and recycled rubber aggregate.
Jiaqing Wang; Qingli Dai; Ruizhe Si; Shuaicheng Guo. Mechanical, durability, and microstructural properties of macro synthetic polypropylene (PP) fiber-reinforced rubber concrete. Journal of Cleaner Production 2019, 234, 1351 -1364.
AMA StyleJiaqing Wang, Qingli Dai, Ruizhe Si, Shuaicheng Guo. Mechanical, durability, and microstructural properties of macro synthetic polypropylene (PP) fiber-reinforced rubber concrete. Journal of Cleaner Production. 2019; 234 ():1351-1364.
Chicago/Turabian StyleJiaqing Wang; Qingli Dai; Ruizhe Si; Shuaicheng Guo. 2019. "Mechanical, durability, and microstructural properties of macro synthetic polypropylene (PP) fiber-reinforced rubber concrete." Journal of Cleaner Production 234, no. : 1351-1364.
Corrosion is one of the most severe threats to the stability of steel bridges and regular rust removal techniques is needed for the maintenance of steel bridges. Currently the correlation between rust development/removal process and the structural/environmental performance of the steel bridges has not been fully understood. This study intends to fill this knowledge gap through critically reviewing. The characteristic analysis of the rust on the corroded steel bridges was first introduced, which provided information that was needed to understand the corrosion mechanisms and classify the rust type. Then the related rust removal techniques (chemical and physical methods) are analyzed by considering the environmental impact and cleaning efficiency. Based on the discussion, the laser cleaning method is proposed due to its cleaning efficiency and environmentally friendliness. After that, the influence of developed rust (uniform and pitting) on the structural performance (static and dynamic) of steel members were summarized. Through the discussion, the potential environmental impact of the corroded steel bridges was identified, including runoff of heavy metal and bacteria growth caused by iron rust. Besides that, an improved kinetic model was proposed by considering the influence of rust removal on the corrosion rate. Furthermore, the structural impact of laser cleaning was simulated with the finite element analysis. This study will serve as solid base for the future studies of corrosion development and rust removal on steel bridges, and the proposed technical routes can be proceeded during future studies to better understand the environmental and structural performance of the steel bridges.
Shuaicheng Guo; Ruizhe Si; Qingli Dai; Zhanping You; Yunxiang Ma; Jiaqing Wang. A critical review of corrosion development and rust removal techniques on the structural/environmental performance of corroded steel bridges. Journal of Cleaner Production 2019, 233, 126 -146.
AMA StyleShuaicheng Guo, Ruizhe Si, Qingli Dai, Zhanping You, Yunxiang Ma, Jiaqing Wang. A critical review of corrosion development and rust removal techniques on the structural/environmental performance of corroded steel bridges. Journal of Cleaner Production. 2019; 233 ():126-146.
Chicago/Turabian StyleShuaicheng Guo; Ruizhe Si; Qingli Dai; Zhanping You; Yunxiang Ma; Jiaqing Wang. 2019. "A critical review of corrosion development and rust removal techniques on the structural/environmental performance of corroded steel bridges." Journal of Cleaner Production 233, no. : 126-146.
Application of rubber particle from the scrap tire through dry-process is a practical and economical efficient way to resolve the recycling problem and environmental concern of the disposed tires. However, the added rubber aggregate reduces both the strength and durability of the rubberized asphalt mixture. This study aims to improve the strength and durability of dry-processed asphalt mixture by using the cement (Portland Type Ⅰ) coating methods and gap-gradation system (Stone Matrix Asphalt (SMA)). The cement coating was applied to enhance the bonding performance between rubber aggregate and asphalt binder, and limits its expansion due to swelling in hot asphalt binder. The SMA mixtures were prepared with different sizes and proportions of mineral aggregates. The samples with conventional aggregate and untreated rubber aggregate both serve as control samples for the sample evaluation. Finally, tests on tensile strength, moisture susceptibility, rutting resistance, anti-stripping resistance, fatigue cracking resistance, and bonding between rubber particles and asphalt binder of SMA mixtures were conducted. The results showed that SMA mixture with pre-coated rubber aggregate owns similar performance comparing to the samples prepared with conventional aggregate and also has higher strength and better performance than that of the mixture with untreated rubber aggregate. Results also clearly indicated that the asphalt mixtures with 50% of No.16 mineral aggregates replaced by pre-coated rubber aggregates performed the best-satisfied performances; while, with a further increase in replaced size or proportion, the satisfied performances of SMA mixtures would be degenerated.
Fangyuan Gong; Shuaicheng Guo; Siyu Chen; Zhanping You; Yu Liu; Qingli Dai. Strength and durability of dry-processed stone matrix asphalt containing cement pre-coated scrap tire rubber particles. Construction and Building Materials 2019, 214, 475 -483.
AMA StyleFangyuan Gong, Shuaicheng Guo, Siyu Chen, Zhanping You, Yu Liu, Qingli Dai. Strength and durability of dry-processed stone matrix asphalt containing cement pre-coated scrap tire rubber particles. Construction and Building Materials. 2019; 214 ():475-483.
Chicago/Turabian StyleFangyuan Gong; Shuaicheng Guo; Siyu Chen; Zhanping You; Yu Liu; Qingli Dai. 2019. "Strength and durability of dry-processed stone matrix asphalt containing cement pre-coated scrap tire rubber particles." Construction and Building Materials 214, no. : 475-483.
Using the crushed waste Cathode Ray Tube (CRT) glass as fine aggregate to produce concrete can be an efficient method to resolve the recycling issue. However, the mediocre mechanical properties of CRT concrete obstructed its wide application. This study aims to resolve this issue based on the study on concrete/mortar specimen incorporating with an innovated surface treatment method. Specifically, a two-step surface treatment method was proposed to improve the performance of CRT concrete by modifying the surface layer of CRT glass sands with NaOH solution and Al(NO3)3 solution. About 30% of the portland cement was replaced with class-F fly ash to mitigate possible ASR damage by the reactive CRT aggregate. The mechanical performance (Compressive/flexural strength, dynamic modulus of elasticity, and flexural fracture energy) and the durability performance (Drying shrinkage and ASR expansion) was examined and compared among different specimens. In addition, the leaching levels of lead in different concrete specimens was evaluated by toxicity characteristic leaching procedure (TCLP). The results showed that the surface treatment method of CRT glass sands could obviously improve both the mechanical properties and durability performance. Particularly, the leaching of lead (Pb) level in all concrete specimens was much lower than the TCLP heavy metals limit of 5mg/L. This experimental study will facilitate the production of CRT glass concrete for the secondary structural applications.
Jiaqing Wang; Shuaicheng Guo; Qingli Dai; Ruizhe Si; Yunxiang Ma. Evaluation of cathode ray tube (CRT) glass concrete with/without surface treatment. Journal of Cleaner Production 2019, 226, 85 -95.
AMA StyleJiaqing Wang, Shuaicheng Guo, Qingli Dai, Ruizhe Si, Yunxiang Ma. Evaluation of cathode ray tube (CRT) glass concrete with/without surface treatment. Journal of Cleaner Production. 2019; 226 ():85-95.
Chicago/Turabian StyleJiaqing Wang; Shuaicheng Guo; Qingli Dai; Ruizhe Si; Yunxiang Ma. 2019. "Evaluation of cathode ray tube (CRT) glass concrete with/without surface treatment." Journal of Cleaner Production 226, no. : 85-95.
Asphalt aging is one of the most severe threats to the asphalt pavement durability and rejuvenation with cooking oil can help to resolve this issue. Currently, the influence of aging/rejuvenation on the bonding performance of asphalt binder has not been fully understood. This study aims to unveil the influence of aging/rejuvenation on the adhesion performance under both micro and macro scale tests. Three type asphalt binders were examined in this study, including the original, aged and rejuvenated samples. The atomic force microscope (AFM) was first applied to examine the surface morphology and adhesion performance of the three type asphalt samples. It is found that the aging effect can increase the adhesion between asphalt binder and silica particles and the adhesion force can be further enhanced through rejuvenation. Then the three-point bending was further conducted to examine adhesion performance at the macroscale, and the obtained results are in accordance with those obtained at the microscale. However, the slant shear test indicated the shear bond strength can be reduced due to the rejuvenation with vegetable oil, which can be generated due to the lubrication effect of the oil. The results in this study can help to better understand the influence of aging and rejuvenation on the bond performance between asphalt binder and mineral aggregate.
Wenbo Ma; Tianbao Huang; Shuaicheng Guo; Caiqian Yang; Yanhuai Ding; Cong Hu. Atomic force microscope study of the aging/rejuvenating effect on asphalt morphology and adhesion performance. Construction and Building Materials 2019, 205, 642 -655.
AMA StyleWenbo Ma, Tianbao Huang, Shuaicheng Guo, Caiqian Yang, Yanhuai Ding, Cong Hu. Atomic force microscope study of the aging/rejuvenating effect on asphalt morphology and adhesion performance. Construction and Building Materials. 2019; 205 ():642-655.
Chicago/Turabian StyleWenbo Ma; Tianbao Huang; Shuaicheng Guo; Caiqian Yang; Yanhuai Ding; Cong Hu. 2019. "Atomic force microscope study of the aging/rejuvenating effect on asphalt morphology and adhesion performance." Construction and Building Materials 205, no. : 642-655.
The epoxy-based polymer concrete has been widely used for concrete repairing and overlays due to good mechanical properties and durability. To reduce environmental landfill problems with the accumulation of tire rubbers, scrap tire rubbers were added to epoxy polymer concrete in this investigation. The crumb rubber (with mesh size #50, 0.279 mm) were introduced into epoxy concrete with two different contents of 5% and 10% based on the epoxy monomer weight. The mechanical properties including direct tensile strength, compressive strength, splitting tensile strength and interface bond strength. Thermal- and moisture-related durability performance of rubberized epoxy concrete were measured and compared with the control samples. The compressive strength and splitting tensile strength were improved with the added 5% solid rubbers, and slightly reduced with 10% content. With a specially-designed testing method, the interface tensile bonding strength between the epoxy concrete overlay and concrete slab were measured as higher than 250 psi for both control and rubberized samples. The thermal conductivity of polymer concrete was reduced with the increase of rubber contents. In addition, very low water absorption rates (<0.5%) were measured with all types of epoxy concrete samples. The interface microstructure with SEM also indicated the good bonds between rubber particles and epoxy resins. The overall test results showed the enhanced performance of rubber-modified epoxy concrete which can facilitate the tire rubber recycling into epoxy polymer concrete for protecting the exist concrete pavement structures.
Jiaqing Wang; Qingli Dai; Shuaicheng Guo; Ruizhe Si. Mechanical and durability performance evaluation of crumb rubber-modified epoxy polymer concrete overlays. Construction and Building Materials 2019, 203, 469 -480.
AMA StyleJiaqing Wang, Qingli Dai, Shuaicheng Guo, Ruizhe Si. Mechanical and durability performance evaluation of crumb rubber-modified epoxy polymer concrete overlays. Construction and Building Materials. 2019; 203 ():469-480.
Chicago/Turabian StyleJiaqing Wang; Qingli Dai; Shuaicheng Guo; Ruizhe Si. 2019. "Mechanical and durability performance evaluation of crumb rubber-modified epoxy polymer concrete overlays." Construction and Building Materials 203, no. : 469-480.
In this study, the Polyvinyl Alcohol (PVA) fiber was introduced to improve the performance of the rubberized concrete. This study experimentally investigated the mechanical performance and durability of Polyvinyl Alcohol (PVA) fiber-reinforced rubber concrete. The waste rubber particles (mesh size #10–#30) were selected to partially replace fine aggregates in the plain concrete. In addition, the rubber particles were pre-treated with an alkali solution to enhance the interface bond with cement paste. The fiber-reinforced rubber concrete samples were prepared with different fine aggregate replacement ratios based on the volume of fine aggregate (15%, 20%, and 25%) and a selected fiber content (0.5% based on the total volume of the mixture). For those samples, the mechanical properties, including compressive strength, flexural behavior, and fracture energy were evaluated to compare with control samples. The results showed that fiber-reinforced samples can largely improve the post-cracking extension and fracture energy. The results of electrical resistivity test indicated the reduced permeability in the fiber-reinforced rubber concrete. The durability performance including Alkali-Silica reaction (ASR) expansion, drying shrinkage and freeze-thaw resistance were also investigated and compared with the control samples. All the durability performances were enhanced through rubber stress release and fiber crack bridging. Therefore, the PVA-fiber reinforced rubber concrete can improve durability and ductility of cementitious materials for structure construction and also can facilitate the recycling of waste rubber into cementitious materials.
Jiaqing Wang; Qingli Dai; Ruizhe Si; Shuaicheng Guo. Investigation of properties and performances of Polyvinyl Alcohol (PVA) fiber-reinforced rubber concrete. Construction and Building Materials 2018, 193, 631 -642.
AMA StyleJiaqing Wang, Qingli Dai, Ruizhe Si, Shuaicheng Guo. Investigation of properties and performances of Polyvinyl Alcohol (PVA) fiber-reinforced rubber concrete. Construction and Building Materials. 2018; 193 ():631-642.
Chicago/Turabian StyleJiaqing Wang; Qingli Dai; Ruizhe Si; Shuaicheng Guo. 2018. "Investigation of properties and performances of Polyvinyl Alcohol (PVA) fiber-reinforced rubber concrete." Construction and Building Materials 193, no. : 631-642.
A major concern with the application of water-foamed asphalt mixtures is the possible performance degradation caused by the presence of inclusion water during production. Inclusion water left in the asphalt mixture after compaction affects the performance of the asphalt mixture. The objectives of this study are to investigate the impact of different foaming conditions on the performance of water-foamed asphalt mixtures prepared using oven-dried aggregates, examine the freeze-thaw resistance of water-foamed asphalt mixtures, and assess the water-foamed asphalt mixture damage level after multiple freeze-thaw cycles through an ultrasonic direct test. The samples for this study were prepared in the laboratory based on the method of Superpave mix design. The control groups were mixed and compacted at 135°C and 148°C, respectively. The water-foamed asphalt binders were prepared at different foaming temperatures, i.e., 120°C and 135°C, and the amount of water agent used in this process was 0.0%–2.0% by mass of asphalt binder. The water-foamed asphalt samples were mixed at various foaming temperatures but compacted at 135°C. Based on the laboratory test results, the foaming temperature and the inclusion water from the foaming process significantly affected the air void and the tensile strength of the asphalt mixture and the void in the mineral aggregate. The freeze-thaw cycle accelerated the destruction of the internal structure of the asphalt mixture and resulted in an increase in porosity and decrease in cohesive strength between the asphalt binder and aggregate. The ultrasonic direct test method was found to be a feasible approach to assessing the potential damage in water-foamed asphalt mixtures.
Lingyun You; Zhanping You; Qingli Dai; Shuaicheng Guo; Jiaqing Wang; Meghan Schultz. Characteristics of Water-Foamed Asphalt Mixture under Multiple Freeze-Thaw Cycles: Laboratory Evaluation. Journal of Materials in Civil Engineering 2018, 30, 04018270 .
AMA StyleLingyun You, Zhanping You, Qingli Dai, Shuaicheng Guo, Jiaqing Wang, Meghan Schultz. Characteristics of Water-Foamed Asphalt Mixture under Multiple Freeze-Thaw Cycles: Laboratory Evaluation. Journal of Materials in Civil Engineering. 2018; 30 (11):04018270.
Chicago/Turabian StyleLingyun You; Zhanping You; Qingli Dai; Shuaicheng Guo; Jiaqing Wang; Meghan Schultz. 2018. "Characteristics of Water-Foamed Asphalt Mixture under Multiple Freeze-Thaw Cycles: Laboratory Evaluation." Journal of Materials in Civil Engineering 30, no. 11: 04018270.
This study aims to investigate the influence of lithium and calcium content on the alkali-silica reaction kinetics and phase formation processes at atomic scales. The atomic structure of the reacted ASR gels was analyzed with the Pair Distribution Function (PDF) measurement. The analysis results can explain the expansion potential difference of gels with different chemical composition. The in situ PDF characterizations of the samples containing lithium compounds identified the formation of the LiSi phase, and thus both the alkali-silica reaction and the reaction between dissolved silica and Ca(OH)2 were suppressed. The alkali-silica reaction kinetics was further indicated with the changes of SiO peak intensity. The amorphous structure of the generated LiSi phase was confirmed with in situ XRD tests. The results strongly support the formed amorphous LiSi phase can act as a surface barrier for silica dissolution, and thus prohibit both the alkali-silica reaction and pozzolanic reaction in hardened concrete.
Shuaicheng Guo; Qingli Dai; Ruizhe Si. Effect of calcium and lithium on alkali-silica reaction kinetics and phase development. Cement and Concrete Research 2018, 115, 220 -229.
AMA StyleShuaicheng Guo, Qingli Dai, Ruizhe Si. Effect of calcium and lithium on alkali-silica reaction kinetics and phase development. Cement and Concrete Research. 2018; 115 ():220-229.
Chicago/Turabian StyleShuaicheng Guo; Qingli Dai; Ruizhe Si. 2018. "Effect of calcium and lithium on alkali-silica reaction kinetics and phase development." Cement and Concrete Research 115, no. : 220-229.
This paper computationally and experimentally investigated the microwave healing performance of graphite (flake graphite and exfoliated graphite nanoplatelet (xGNP)) modified asphalt mixture. The original fracture energy and strength were first measured for the modified asphalt mixture through the disk-shaped compact tension test. Then the micro-wave healing performance (recovered fracture energy and strength) were further examined. All these were enhanced with the added carbon materials. The recovered fracture strengths were also compared with FE cohesive zone model (CZM) simulation with digital image correlation (DIC) calibrated parameters. The predicted recovered fracture strength had good agreement with the experimental measurement.
Zigeng Wang; Qingli Dai; Shuaicheng Guo. Microwave-healing performance of modified asphalt mixtures with flake graphite and exfoliated graphite nanoplatelet. Construction and Building Materials 2018, 187, 865 -875.
AMA StyleZigeng Wang, Qingli Dai, Shuaicheng Guo. Microwave-healing performance of modified asphalt mixtures with flake graphite and exfoliated graphite nanoplatelet. Construction and Building Materials. 2018; 187 ():865-875.
Chicago/Turabian StyleZigeng Wang; Qingli Dai; Shuaicheng Guo. 2018. "Microwave-healing performance of modified asphalt mixtures with flake graphite and exfoliated graphite nanoplatelet." Construction and Building Materials 187, no. : 865-875.
The effects of calcium on the atomic structure of alkali‐activated binder materials were investigated. The alkali‐activated binder samples with varied Ca/Si ratios were first statically examined with both the X‐ray diffraction (XRD) and total scattering function analysis. The added calcium can re‐order the atomic structure of the alkali‐activated materials and enhance its crystallization based on the X‐ray pair distribution function (PDF) and XRD analysis. In situ PDF experiments were undertaken to examine the evolution of the atomic structure of calcium‐contained geopolymer. The increase of calcium content accelerated the dissolution of precursor and the formation of the binder. It was shown that the additional Ca(OH)2 could serve as nucleation sites for the precipitation of NASH gel to accelerate the reaction. PDF analysis and XRD characterization enable the examination of the phase development of alkali‐activated materials at the atomic scale.
Ruizhe Si; Shuaicheng Guo; Qingli Dai. Influence of calcium content on the atomic structure and phase formation of alkali‐activated cement binder. Journal of the American Ceramic Society 2018, 102, 1479 -1494.
AMA StyleRuizhe Si, Shuaicheng Guo, Qingli Dai. Influence of calcium content on the atomic structure and phase formation of alkali‐activated cement binder. Journal of the American Ceramic Society. 2018; 102 (3):1479-1494.
Chicago/Turabian StyleRuizhe Si; Shuaicheng Guo; Qingli Dai. 2018. "Influence of calcium content on the atomic structure and phase formation of alkali‐activated cement binder." Journal of the American Ceramic Society 102, no. 3: 1479-1494.
This study aims to study the alkali‐silica reaction (ASR) with incorporated kinetic‐thermodynamic analysis. The model reactant tests were first conducted to study the silica dissolution in the simulated pore solution under different temperatures. Then, the kinetic model for silica dissolution was further improved by considering the influence of effective surface area. The improved kinetic model was also incorporated into the GEMS thermodynamic simulation. The model analysis demonstrated the silica dissolution rate is decreased mainly caused by reduced hydroxyl activity with increased saturation degree. The dissolved silica first reacted with the portlandite phase and formed the Calcium‐Silicate‐Hydrate (CSH) gel. The ASR gel can only be generated under high silicate ion concentration after the consumption of portlandite. This article is protected by copyright. All rights reserved.
Shuaicheng Guo; Qingli Dai; Liang Chang; Yunhang Hu; Xinfeng Xie; Ruizhe Si; Jiaqing Wang. Kinetic analysis and thermodynamic simulation of alkali-silica reaction in cementitious materials. Journal of the American Ceramic Society 2018, 102, 1463 -1478.
AMA StyleShuaicheng Guo, Qingli Dai, Liang Chang, Yunhang Hu, Xinfeng Xie, Ruizhe Si, Jiaqing Wang. Kinetic analysis and thermodynamic simulation of alkali-silica reaction in cementitious materials. Journal of the American Ceramic Society. 2018; 102 (3):1463-1478.
Chicago/Turabian StyleShuaicheng Guo; Qingli Dai; Liang Chang; Yunhang Hu; Xinfeng Xie; Ruizhe Si; Jiaqing Wang. 2018. "Kinetic analysis and thermodynamic simulation of alkali-silica reaction in cementitious materials." Journal of the American Ceramic Society 102, no. 3: 1463-1478.
Grouting reinforcement is an important part of modern engineering and has grown in popularity due to the benefits of grouting enhancement on cyclic loading. Understanding the fatigue mechanism of grouting-enhanced structures is vital to the design and the long-term stability analysis of such structures. In this study, the fatigue mechanical properties of cracked cement paste after epoxy resin grouting enhancement under different cyclic conditions were investigated in the laboratory and an inverted S-shaped curve was proposed to describe the damage accumulation. The test results indicated that the fatigue axial deformation can be divided into three stages: the initial stage, constant velocity stage and accelerating stage. The irreversible deformation can be used to describe the damage accumulation. The fatigue process is significantly affected by the upper limit stress level and the stress amplitude. In addition, the exponential relationship between stress amplitude and fatigue life was obtained. The proposed S-shaped curve was validated by an experimental fatigue strain test. The tests result upon various load conditions and crack types represented a good agreement with the predicted data.
Zhi Wang; Long Li; Shuaicheng Guo; Qingli Dai. Nonlinear Fatigue Damage of Cracked Cement Paste after Grouting Enhancement. Applied Sciences 2018, 8, 1105 .
AMA StyleZhi Wang, Long Li, Shuaicheng Guo, Qingli Dai. Nonlinear Fatigue Damage of Cracked Cement Paste after Grouting Enhancement. Applied Sciences. 2018; 8 (7):1105.
Chicago/Turabian StyleZhi Wang; Long Li; Shuaicheng Guo; Qingli Dai. 2018. "Nonlinear Fatigue Damage of Cracked Cement Paste after Grouting Enhancement." Applied Sciences 8, no. 7: 1105.
The quick accumulation of recycled organic components with the modern society development has caused serious environment issues, and the utilization of these recycled organic components in concrete production can effectively mitigate recycling pressure. Portland cement concrete mixes containing recycled organic components behave differently in both fresh and hardened stages compared to conventional concrete, which need to be thoroughly studied before a large-scale field application. This paper aims to critically review the currently-reported performance of concrete with recycled organic components and to identify the knowledge gap for future studies. This paper first conducted the characteristic investigation of recycled organic components, which provided the needed information for the classification of recycled organic components. Then the property performance, including workability, mechanical properties, and durability of concrete containing recycled organic component was evaluated. It has been concluded that both the workability and concrete strength will decrease with the added recycled organic components. However the durability performance, including freeze-thaw, impact resistance, and the resistance to alkali-silica reaction can be enhanced with the added recycled organic components. Aiming at the decreased strength, surface treatment methods have been reviewed. The current finding demonstrated the NaOH surface treatment for rubber particles and oxidation method for reclaimed asphalt mixture aggregates can enhance the concrete performance, respectively. Finally, the practice of applying recycled organic components in high strength and self-consolidating concrete was summarized, which demonstrated the potential of high performance concrete production with recycled organic component. Current knowledge gaps were identified to point out the challenges for the further study, including the difficulties to produce high strength and self-consolidating concrete with replacement ratio of recycled organic components higher than 50%. This study will provide the firm base for the application and future study on concrete containing recycled organic components, including reclaimed asphalt pavement (RAP), recycled asphalt shingles (RAS) and recycled crumb rubber (RCR).
Shuaicheng Guo; Jiong Hu; Qingli Dai. A critical review on the performance of portland cement concrete with recycled organic components. Journal of Cleaner Production 2018, 188, 92 -112.
AMA StyleShuaicheng Guo, Jiong Hu, Qingli Dai. A critical review on the performance of portland cement concrete with recycled organic components. Journal of Cleaner Production. 2018; 188 ():92-112.
Chicago/Turabian StyleShuaicheng Guo; Jiong Hu; Qingli Dai. 2018. "A critical review on the performance of portland cement concrete with recycled organic components." Journal of Cleaner Production 188, no. : 92-112.
Ruizhe Si; Jiaqing Wang; Shuaicheng Guo; Qingli Dai; Song Han. Evaluation of laboratory performance of self-consolidating concrete with recycled tire rubber. Journal of Cleaner Production 2018, 180, 823 -831.
AMA StyleRuizhe Si, Jiaqing Wang, Shuaicheng Guo, Qingli Dai, Song Han. Evaluation of laboratory performance of self-consolidating concrete with recycled tire rubber. Journal of Cleaner Production. 2018; 180 ():823-831.
Chicago/Turabian StyleRuizhe Si; Jiaqing Wang; Shuaicheng Guo; Qingli Dai; Song Han. 2018. "Evaluation of laboratory performance of self-consolidating concrete with recycled tire rubber." Journal of Cleaner Production 180, no. : 823-831.