materials-logo

Journal Browser

Journal Browser

Sustainable, Self-Healing, and Functional Building Materials

A special issue of Materials (ISSN 1996-1944). This special issue belongs to the section "Construction and Building Materials".

Deadline for manuscript submissions: closed (20 April 2022) | Viewed by 28376

Special Issue Editors


E-Mail Website
Guest Editor
Key Laboratory of Advanced Civil Engineering Materials of Ministry of Education, School of Materials Science and Engineering, Tongji University, Shanghai 200092, China
Interests: cement-based materials; self-healing cementitious materials; low carbon cementitious materials; materials performance under extreme environment

E-Mail Website
Guest Editor
College of Civil and Transportation Engineering, Shenzhen University, Shenzhen 518060, China
Interests: functional building materials; smart building materials; sustainable building materials; durability of concrete
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

Concrete is the most frequently used building material, which accounts for 5–10% of global CO2 emissions. Due to the brittle nature of concrete, cracking and cracking-related deterioration are among the most important factors threatening the integrity, durability, and safety of concrete structures. Self-healing, a phenomenon originating from biological systems, is a promising concept that can be adopted to treat cracks in cementitious materials. Attaching such new function to cementitious materials can extend the service life of concrete structures and mitigate the depletion of natural resources, energy consumption, and CO2 emissions associated with concrete production and structural maintenance. This could be an important approach towards the sustainability of the modern cement and concrete industry.

The self-healing of cementitious materials can be achieved mainly through the following three strategies: (i) autogenous healing; (ii) the encapsulation of polymeric materials; (iii) the microbial production of minerals (i.e., calcium carbonate).

In autogenous healing, which is considered a natural phenomenon, concrete cracks are filled through the hydration of unhydrated cement particles or the carbonation of dissolved calcium hydroxide in the presence of moisture or water.

The encapsulation of polymeric materials can contribute to filling cracks by the conversion of healing agent to foam in the presence of moisture. The polymeric adhesives are often designed to provide extrinsic sealing through the polymerization and coalescence of the adhesives. Polymeric adhesives can also fill the cracks and harden when in contact with the alkalis or hydroxide ions.

Biological healing processes are based on the production of minerals by living organisms through biomineralization, which is a widespread phenomenon in nature. In this process, biominerals are formed through the reaction of metabolic products generated by microorganisms with the surrounding environment. Among the various pathways of mineral production through biomineralization—such as carbonates, sulfides, silicates, and phosphates—the precipitation of calcium carbonate has attracted widespread interest due to its efficient bonding capacity and compatibility with concrete compositions.

In this Special Issue, modern trends in self-healing concrete preparation, including the healing fundamentals and mechanisms as well as the properties of healed concrete, are highlighted and discussed. Sustainable techniques and new functional materials related to self-healing cementitious materials will also be covered.

It is my pleasure to invite you to submit a manuscript for publication in this Special Issue. Full papers, communications, and reviews are all welcome.

Prof. Dr. Zhengwu Jiang
Prof. Dr. Biqin Dong
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Materials is an international peer-reviewed open access semimonthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • concrete
  • self-healing cementitious materials
  • sustainable cementitious materials
  • functional building materials
  • healing mechanisms
  • crack filling
  • microstructure
  • mechanical properties

Benefits of Publishing in a Special Issue

  • Ease of navigation: Grouping papers by topic helps scholars navigate broad scope journals more efficiently.
  • Greater discoverability: Special Issues support the reach and impact of scientific research. Articles in Special Issues are more discoverable and cited more frequently.
  • Expansion of research network: Special Issues facilitate connections among authors, fostering scientific collaborations.
  • External promotion: Articles in Special Issues are often promoted through the journal's social media, increasing their visibility.
  • e-Book format: Special Issues with more than 10 articles can be published as dedicated e-books, ensuring wide and rapid dissemination.

Further information on MDPI's Special Issue polices can be found here.

Published Papers (12 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Research

12 pages, 3148 KiB  
Article
Study on Autolytic Mechanism and Self-Healing Properties of Autolytic Clinker Microsphere in Alkaline Environment
by Jun Li, Wenting Li and Zhengwu Jiang
Materials 2022, 15(10), 3638; https://doi.org/10.3390/ma15103638 - 19 May 2022
Cited by 3 | Viewed by 1265
Abstract
In this study, the autolytic clinker microsphere with clinker as core and polyvinyl pyrrolidone (PVP) as coating film was prepared. Pretreatment of clinker with silane coupling agent was firstly processed during the preparation. To investigate the autolytic mechanism, the microstructures of the autolytic [...] Read more.
In this study, the autolytic clinker microsphere with clinker as core and polyvinyl pyrrolidone (PVP) as coating film was prepared. Pretreatment of clinker with silane coupling agent was firstly processed during the preparation. To investigate the autolytic mechanism, the microstructures of the autolytic clinker microsphere at different curing ages were observed using environmental scanning electron microscopy (ESEM), equipped with an energy dispersive spectrometer (EDS). The autolytic stages were also identified based on the microstructural evolution. The influence of pretreatment degree on autolytic behavior was also studied by measurements of micro-morphology and isothermal calorimetry. Experimental results indicated that the compressive strength recovery of specimens was increased by 15–19% due to the addition of autolytic clinker microspheres. The recovery of compressive strength was also improved with the increase of pH value. The improvements in compressive strength recovery of specimens with microspheres were in the range of 15–19%, 15–31%, 25–36%, and 29–50% with the pH value of 7, 8, 10, and 12, respectively. It was also found that inner damage of cement-based matrix had greater recovery when pre-cracked specimens were cured in alkaline environments. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

14 pages, 2357 KiB  
Article
Design and Preparation of White High-Strength Concrete with Ground Limestone Powder by Means of Response Surface Methodology
by Jingliang Xia, Changwei Cao, Zhengwu Jiang, Qiang Ren, Ying Zhang, Jing Wang and Faguang Leng
Materials 2022, 15(9), 3359; https://doi.org/10.3390/ma15093359 - 7 May 2022
Cited by 2 | Viewed by 2022
Abstract
This paper investigates the properties of white high-strength concrete (WHSC) prepared with ground limestone powder (GLP). Response surface methodology (RSM) was used to design the proportions of mixes and evaluate the influence of the water–binder ratio (w/b), slurry volume fraction (Vs), and the [...] Read more.
This paper investigates the properties of white high-strength concrete (WHSC) prepared with ground limestone powder (GLP). Response surface methodology (RSM) was used to design the proportions of mixes and evaluate the influence of the water–binder ratio (w/b), slurry volume fraction (Vs), and the content of GLP in a binder (Cg) on the slump, whiteness and compressive strength of WHSC via Box–Behnken equations. Results indicate that quadratic polynomial regression equations can be used to predict the performance of WHSC as influenced by combined factors. Both slump and compressive strength of WHSC are found highly influenced by w/b while GLP significantly improves the whiteness of WHSC. An optimal mix proportion of WHSC is provided by the multi-objective optimization with high-accuracy predictions. This paper demonstrates the feasibility of preparing WHSC with GLP and presents the potential of using RSM in the mix proportioning of concrete. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

14 pages, 9953 KiB  
Article
Effect and Mechanism of Polyethylene Glycol (PEG) Used as a Phase Change Composite on Cement Paste
by Chunpeng Zhang, Chaoming Pang, Yunrui Mao and Zhiyuan Tang
Materials 2022, 15(8), 2749; https://doi.org/10.3390/ma15082749 - 8 Apr 2022
Cited by 14 | Viewed by 3121
Abstract
The use of phase change materials (PCMs) in the construction industry is one of the primary strategies for addressing the building industry’s present excessive energy usage. However, since PCMs must be enclosed before being used in construction, their efficiency is limited and their [...] Read more.
The use of phase change materials (PCMs) in the construction industry is one of the primary strategies for addressing the building industry’s present excessive energy usage. However, since PCMs must be enclosed before being used in construction, their efficiency is limited and their compatibility with concrete is poor. Thus, polyethylene glycol (PEG), a sequence of PCMs that may be put directly into concrete, is the target of this research. The fluidity, mechanical properties, thermal properties, hydration process, and hydration products of PEG-600 cement slurry were examined by TAM, XRD, FTIR, DSC, MALDI, etc., methods in this study. Furthermore, we tested the thermal properties of PEG-800 to confirm that the same depolymerization of PEG occurred in an alkaline environment. When PEG, with a molecular weight of 600 (PEG-600), dose was increased to 10%, both compressive and flexural strength fell by 19% and 18%, respectively. The phase change points of both PEG-600 cement paste and PEG-800 cement paste decreased to 10~15 °C, and the enthalpy of the phase change was about 6 J/g. Additionally, it was discovered that PEG entered the reaction during the hydration step. PEG underwent depolymerization and subsequently formed a complex with Ca2+. However, due to the large dose of PEG used in this investigation, a self-curing effect of PEG in concrete was not seen. The findings of this research suggest a novel use for PCMs: PEG may be directly applied to concrete to fulfill both mechanical and thermal requirements. Additionally, the number of hydration products and phase compositions remained almost constant. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

14 pages, 3273 KiB  
Article
Improving Self-Healing and Shrinkage Reduction of Cementitious Materials Using Water-Absorbing Polymer Microcapsules
by Qianjin Mao, Jiayi Chen, Wenjing Qi, Hui Liu, Ziming Wang and Suping Cui
Materials 2022, 15(3), 847; https://doi.org/10.3390/ma15030847 - 23 Jan 2022
Cited by 11 | Viewed by 2604
Abstract
Self-healing cementitious materials are a promising means for ensuring sustainable concrete infrastructure and promoting long-term service lives. To obtain microcapsules that are versatile in varying environments, in this study, absorbing microcapsules with calcium alginate as the shell and epoxy resin as the core [...] Read more.
Self-healing cementitious materials are a promising means for ensuring sustainable concrete infrastructure and promoting long-term service lives. To obtain microcapsules that are versatile in varying environments, in this study, absorbing microcapsules with calcium alginate as the shell and epoxy resin as the core were prepared. The absorbing microcapsules exhibit self-healing and can reduce the shrinkage of cementitious materials. Volume changes of the microcapsules in the hardened paste with increasing hydration age were observed using three-dimensional X-ray computed tomography. In the hardened cement paste with a water-cement ratio of 0.29, the absorption of the microcapsules lasted for several days, and the release of water lasted for 28 days. The absorption of microcapsules affected the fluidity of cement paste, and it was significantly weakened and delayed due to the lower absorption rate. The addition of absorbing microcapsules significantly reduced the autogenous and drying shrinkage of mortars. For microcapsules with a core content of 55% added at 3.5% of cement weight, autogenous shrinkage was almost eliminated. Most importantly, the addition of absorbing microcapsules could achieve a certain degree of recovery of compressive strength as well as satisfactory recovery of impermeability in dry and wet environments. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

13 pages, 2576 KiB  
Article
The Coupling Effect of Organosilicon Hydrophobic Agent and Cement on the Water Resistance of Phosphogypsum
by Pengfei Ma, Chong Wang, Yuxin Gao, Xiaowei Gu, Baojun Cheng, Zheng Fang, Guangqi Xiong and Jing Wu
Materials 2022, 15(3), 845; https://doi.org/10.3390/ma15030845 - 22 Jan 2022
Cited by 6 | Viewed by 2396
Abstract
The objective of this paper is to investigate the coupling effect of cement and organosilicon hydrophobic agents on the water resistance of phosphogypsum. Different weight ratios of Portland cement were added to adjust the alkalinity of this system and further improve the work [...] Read more.
The objective of this paper is to investigate the coupling effect of cement and organosilicon hydrophobic agents on the water resistance of phosphogypsum. Different weight ratios of Portland cement were added to adjust the alkalinity of this system and further improve the work efficiency of the organosilicon hydrophobic agents. Some macroscopic performances, such as the water absorption, the compressive strength, the flexural strength, and the softening coefficient, were measured to characterize the water-resistance of phosphogypsum. The microscopic characteristics were analyzed via contact angle tests, scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS) to understand the mechanism of organosilicon hydrophobicity. The results indicated that both the compressive and flexural strengths of phosphogypsum first increased and then decreased with the increase of organosilicon hydrophobic agents. Meanwhile, the surface contact angle continued to increase and the softening coefficient exhibited an obvious increase. When the hydrophobic agent was combined with Portland cement, the softening coefficient of phosphogypsum further increased from 0.80 to 0.99, while the water absorption rate was significantly reduced from 16.0% to 0.8%. Microscopic tests proved that the hydrophobic organic molecules can be polymerized under the high alkalinity, and promote the formation of a hydrophobic film, thus significantly improving the water-resistance of phosphogypsum. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

13 pages, 3221 KiB  
Article
Effect of Calcination Temperature on Mechanical Properties of Magnesium Oxychloride Cement
by Chenggong Chang, Lingyun An, Rui Lin, Jing Wen, Jinmei Dong, Weixin Zheng, Fengyun Yan and Xueying Xiao
Materials 2022, 15(2), 607; https://doi.org/10.3390/ma15020607 - 14 Jan 2022
Cited by 10 | Viewed by 2180
Abstract
In order to make full use of magnesium chloride resources, the development and utilisation of magnesium oxychloride cement have become an ecological and economic goal. Thus far, however, investigations into the effects on these cements of high temperatures are lacking. Herein, magnesium oxychloride [...] Read more.
In order to make full use of magnesium chloride resources, the development and utilisation of magnesium oxychloride cement have become an ecological and economic goal. Thus far, however, investigations into the effects on these cements of high temperatures are lacking. Herein, magnesium oxychloride cement was calcinated at various temperatures and the effects of calcination temperature on microstructure, phase composition, flexural strength, and compressive strength were studied by scanning electron microscopy, X-ray diffraction, and compression testing. The mechanical properties varied strongly with calcination temperature. Before calcination, magnesium oxychloride cement has a needle-like micromorphology and includes Mg(OH)2 gel and a trace amount of gel water as well as 5 Mg(OH)2·MgCl2·8H2O, which together provide its mechanical properties (flexural strength, 18.4 MPa; compressive strength, and 113.3 MPa). After calcination at 100 °C, the gel water is volatilised and the flexural strength is decreased by 57.07% but there is no significant change in the compressive strength. Calcination at 400 °C results in the magnesium oxychloride cement becoming fibrous and mainly consisting of Mg(OH)2 gel, which helps to maintain its high compressive strength (65.7 MPa). When the calcination temperature is 450 °C, the microstructure becomes powdery, the cement is mainly composed of MgO, and the flexural and compressive strengths are completely lost. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

16 pages, 11616 KiB  
Article
Research on Damage and Deterioration of Fiber Concrete under Acid Rain Environment Based on GM(1,1)-Markov
by Jianqiao Yu, Hongxia Qiao, Feifei Zhu and Xinke Wang
Materials 2021, 14(21), 6326; https://doi.org/10.3390/ma14216326 - 23 Oct 2021
Cited by 17 | Viewed by 1894
Abstract
With steel fiber and basalt fiber volume dosing serving as variation parameters, a total of 200 d cycles of acid rain corrosion cycle tests were conducted on fiber concrete in this study. We selected three durability evaluation parameters to assess the degree of [...] Read more.
With steel fiber and basalt fiber volume dosing serving as variation parameters, a total of 200 d cycles of acid rain corrosion cycle tests were conducted on fiber concrete in this study. We selected three durability evaluation parameters to assess the degree of damage deterioration on fiber concrete, used scanning electron microscopy, mercury intrusion porosimetry, and a dimensional microhardness meter to analyze the concrete micromorphology, and established a GM(1,1)-Markov model for life prediction of its durability. Results reveal that the acid rain environment is the most sensitive to the influence of the relative dynamic elastic modulus evaluation parameter, and concrete has specimens that show failure damage under this parameter evaluation. Incorporation of fibers can reduce the amount of corrosion products inside the concrete, decrease the proportion of harmful pores, optimize the mean pore-size, and significantly improve the resistance to acid rain attack. Concrete with 2% steel fiber and 0.1% basalt fiber by volume has the least change in durability damage, and the predicted service life by GM(1,1)-Markov model is 322 d. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

19 pages, 5573 KiB  
Article
Time-Dependent Shrinkage Model for Recycled Fine Aggregate Thermal Insulation Concrete
by Xuhang Zang, Pinghua Zhu, Chunhong Chen, Xiancui Yan and Xinjie Wang
Materials 2021, 14(19), 5581; https://doi.org/10.3390/ma14195581 - 26 Sep 2021
Cited by 3 | Viewed by 1775
Abstract
In this study, the shrinkage performance of recycled aggregate thermal insulation concrete (RATIC) with added glazed hollow beads (GHB) was investigated and a time-dependent shrinkage model was proposed. Two types of recycled fine aggregate (RFA) were used to replace natural fine aggregate in [...] Read more.
In this study, the shrinkage performance of recycled aggregate thermal insulation concrete (RATIC) with added glazed hollow beads (GHB) was investigated and a time-dependent shrinkage model was proposed. Two types of recycled fine aggregate (RFA) were used to replace natural fine aggregate in RATIC: RFA from waste concrete (RFA1) and waste clay brick (RFA2). Besides, the mechanical properties and thermal insulation performance of RATIC were also studied. Results showed that the pozzolanic reaction caused by RFA2 effectively improved the mechanical properties of RATIC; 75% was the optimal replacement ratio of RATIC prepared by RFA2. Added RFA decreased the thermal conductivity of thermal insulation concrete (TIC). The total shrinkage strain of RATIC increased with the increase of the replacement ratio of RFA. The 150d total shrinkage of RATIC prepared by RFA1 was 1.46 times that of TIC and the 150d total shrinkage of RATIC prepared by RFA2 was 1.23 times. The addition of GHBs led to the increase of early total shrinkage strain of concrete. Under the combined action of the higher elastic modulus of RFA2 and the pozzolanic components contained in RFA2, the total shrinkage strain of RATIC prepared by RFA2 with the same replacement ratio was smaller than that of RATIC prepared by RFA1. For example, the final total shrinkage strain of RATIC prepared by RFA2 at 100% replacement ratio was about 18.6% less than that of RATIC prepared by RFA1. A time-dependent shrinkage model considering the influence of the elastic modulus of RFA and the addition of GHB on the total shrinkage of RATIC was proposed and validated by the experimental results. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

14 pages, 9443 KiB  
Article
Analysis of Compressive Fatigue Failure of Recycled Aggregate Concrete
by Fan You, Surong Luo, Jianlan Zheng and Kaibin Lin
Materials 2021, 14(16), 4620; https://doi.org/10.3390/ma14164620 - 17 Aug 2021
Cited by 5 | Viewed by 1824
Abstract
Using recycled aggregate in concrete is effective in recycling construction and demolition waste. It is of critical significance to understand the fatigue properties of recycled aggregate concrete (RAC) to implement it safely in structures subjected to repeated or fatigue load. In this study, [...] Read more.
Using recycled aggregate in concrete is effective in recycling construction and demolition waste. It is of critical significance to understand the fatigue properties of recycled aggregate concrete (RAC) to implement it safely in structures subjected to repeated or fatigue load. In this study, a series of fatigue tests was performed to investigate the compressive fatigue behavior of RAC. The performance of interfacial transition zones (ITZs) was analyzed by nanoindentation. Moreover, the influence of ITZs on the fatigue life of RAC was discussed. The results showed that the fatigue life of RAC obeyed the Weibull distribution, and the S-N-p equation could be obtained based on the fitting of Weibull parameters. In the high cycle fatigue zone (N104), the fatigue life of RAC was lower than that of natural aggregate concrete (NAC) under the same stress level. The fatigue deformation of RAC presented a three-stage deformation regularity, and the maximum deformation at the point of fatigue failure closely matched the monotonic stress-strain envelope. The multiple ITZs matched the weak areas of RAC, and the negative effect of ITZs on the fatigue life of RAC in the high cycle fatigue zone was found to be greater than that of NAC. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

16 pages, 5869 KiB  
Article
Preparation of Low-Cost Magnesium Oxychloride Cement Using Magnesium Residue Byproducts from the Production of Lithium Carbonate from Salt Lakes
by Pan Liu, Jinmei Dong, Chenggong Chang, Weixin Zheng, Xiuquan Liu, Xueying Xiao and Jing Wen
Materials 2021, 14(14), 3899; https://doi.org/10.3390/ma14143899 - 13 Jul 2021
Cited by 8 | Viewed by 2821
Abstract
Magnesium oxychloride cement (abbreviated as MOC) was prepared using magnesium residue obtained from Li2CO3 extraction from salt lakes as raw material instead of light magnesium oxide. The properties of magnesium residue calcined at different temperatures were researched by XRD, SEM, [...] Read more.
Magnesium oxychloride cement (abbreviated as MOC) was prepared using magnesium residue obtained from Li2CO3 extraction from salt lakes as raw material instead of light magnesium oxide. The properties of magnesium residue calcined at different temperatures were researched by XRD, SEM, LSPA, and SNAA. The preparation of MOC specimens with magnesium residue at different calcination temperatures (from 500 °C to 800 °C) and magnesium chloride solutions with different Baume degrees (24 Baume and 28 Baume) were studied. Compression strength tests were conducted at different curing ages from 3 d to 28 d. The hydration products, microstructure, and porosity of the specimens were analyzed by XRD, SEM, and MIP, respectively. The experimental results showed that magnesium residue’s properties, the BET surface gradually decreased and the crystal size increased with increasing calcination temperature, resulting in a longer setting time of MOC cement. Additionally, the experiment also indicated that magnesium chloride solution with a high Baume makes the MOC cement have higher strength. The MOC specimens prepared by magnesium residue at 800 °C and magnesium chloride solution Baume 28 exhibited a compressive of 123.3 MPa at 28 d, which met the mechanical property requirement of MOC materials. At the same time, magnesium oxychloride cement can be an effective alternative to Portland cement-based materials. In addition, it can reduce environmental pollution and improve the environmental impact of the construction industry, which is of great significance for sustainable development. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

14 pages, 4240 KiB  
Article
Assessment of Electrical Resistivity and Oxygen Diffusion Coefficient of Cementitious Materials from Microstructure Features
by Renzhan Zhou, Qiang Li, Jiandong Wang, Kewen Zhou, Rui He and Chuanqing Fu
Materials 2021, 14(12), 3141; https://doi.org/10.3390/ma14123141 - 8 Jun 2021
Cited by 5 | Viewed by 2464
Abstract
A newly proposed modified non-contact electrical resistivity measurement was used to test the resistivity of concrete and cement mortar. The oxygen diffusion coefficients of concrete and mortar were determined by a gas diffusion measurement, and the capillary porosity of concrete and cement mortar [...] Read more.
A newly proposed modified non-contact electrical resistivity measurement was used to test the resistivity of concrete and cement mortar. The oxygen diffusion coefficients of concrete and mortar were determined by a gas diffusion measurement, and the capillary porosity of concrete and cement mortar was measured by mercury intrusion porosimetry (MIP) measurement. The obtained electrical resistivity and capillary porosity results were verified with other researchers’ data, the measured electrical resistivity results can be estimated by a simple equation from the capillary porosity results. The obtained oxygen diffusion coefficient results were quantitatively correlated with capillary porosity and electrical resistivity measurement results. The proposed equations can be practically used to assess the electrical resistivity and oxygen diffusion coefficient. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

14 pages, 6429 KiB  
Article
Dynamic Compressive Strength Tests of Corroded SFRC Exposed to Drying–Wetting Cycles with a 37 mm Diameter SHPB
by Hui Chen, Xiangqiang Zhou, Qiang Li, Rui He and Xin Huang
Materials 2021, 14(9), 2267; https://doi.org/10.3390/ma14092267 - 27 Apr 2021
Cited by 6 | Viewed by 1943
Abstract
This study focuses on the dynamic compression performance of corroded steel fiber-reinforced concrete (SFRC) exposed to drying–wetting chloride cycles by a 37 mm diameter split Hopkinson pressure bar (SHPB) system. Three steel fiber contents (0.5%, 1.0%, 2.0%, by volume) were incorporated into concrete, [...] Read more.
This study focuses on the dynamic compression performance of corroded steel fiber-reinforced concrete (SFRC) exposed to drying–wetting chloride cycles by a 37 mm diameter split Hopkinson pressure bar (SHPB) system. Three steel fiber contents (0.5%, 1.0%, 2.0%, by volume) were incorporated into concrete, and samples were subjected to drying–wetting cycles for different corrosion durations (30 days, 60 days, 90 days) after 28 days age. The sample damage mode, stress–strain curve and the dynamic compression performance of corroded SFRC were compared with plain concrete. Through the experimental data, strain-rate effect, fiber reinforcement effect and the corrosion duration influence on the impact compression property of SFRC were identified. The dynamic increase factor results of these samples were compared with the existing models in previous published literature. An empirical dynamic increase factor profile characterization model considering fiber content, corrosion duration and strain-rate is proposed. Full article
(This article belongs to the Special Issue Sustainable, Self-Healing, and Functional Building Materials)
Show Figures

Figure 1

Back to TopTop