1. Introduction

2. The marine environment and concrete deterioration

2.2. Microbiological corrosion (biodeterioration)

The study of microbial deterioration of concrete involves materials science, mineralogy and microbial ecology. Many authors have considered the corrosion of concrete in sewer pipes, and biodeterioration in these structures has been thoroughly investigated (see, for example, reviews by [34]; [35]; [36]), but there is relatively scarce information on marine biocorrosion of concrete. Seawater composition and environmental parameters such as temperature, pH and pollution influence not only chemical corrosion of concrete, but also adhering microorganisms. Alternating conditions of wetting and drying have been shown to increase chemical deterioration of poor quality concrete in seawater [37]; whether microbially induced deterioration is also affected is unknown. The microbial species attaching to concrete structures that are permanently or intermittently submerged in seawater might be expected to differ, with intermittently submerged biofilms drying out periodically, favoring the more dehydration resistant organisms. Conversely, the presence of a biofilm could maintain a degree of humidity on the concrete surface, reducing the drying effects of the exposed time period.  Controlled experiments to determine the effects of biofilm on the physicochemical corrosion of concrete have never been performed. Indeed, there is, as yet, no information on the microbiology of concrete subjected to the different sea immersion zones, splash, tidal and submerged.

The microbial content and abundance of the oceans differs enormously around the globe. Does the attached microbial population on concrete differ equally, or is there a specific concrete biofilm on marine structures? The recent enormous interest in marine pollution by microplastics has led to the identification of a plastic-specific biofilm (the “plastisphere”,[38]); whether the equivalent exists for concrete (a concretosphere ?) is unknown, although there is no evidence for this from studies on the better studied sewer pipe corrosion. Recently, however, there have been publications indicating that the initial microbial population attaching to concrete in the marine environment changes with time to produce a common “generic” concrete biofilm with time [39]; [40]; [41] marine corrosion. Earlier results had indicated this possibility. [42] used DGGE analysis to identify the dominance of Thiobacillus thiooxidans and Acidithiobacillus sp. on corroded areas of concrete sewer pipes and [43], using metagenomic techniques on 175 samples from various  surfaces of 9 piers along the Hong Kong coast, identified considerable differences between microbiomes on concrete and metal structures. Interestingly, they found that metal surfaces contained more functional genes involved in iron uptake, while those involved in iron regulation and storage were more common on concrete. Relatively few iron-oxidizing bacteria were found on either type of surface, however. The pier floors yielded higher Cyanobacteria-dominated microbiomes than the walls, consistent with floors wetted by wave action remaining damp for longer. Cyanobacteria rely on liquid water more than chlorophytes, which can use water vapor for growth. Table 1 shows the microorganisms that we have identified in the literature as attaching to concrete under continuous and intermittent seawater exposure conditions. The processes involved in microbial biodeterioration of concrete structures in the marine environment are discussed in the following sections.

Table 1. Some of the microorganisms detected in biofilms on permanently or intermittently immersed concrete.

Table 1. Some of the microorganisms detected in biofilms on permanently or intermittently immersed concrete.

Microorganism	Permanent	Intermittent	Reference	Comments
Lyngbya		+	[94]	Cyanobacteria Yangtze river reservoir
Leptolyngbya		+	[94]	Cyanobacteria Yangtze river reservoir
Cyanobacteria	+	+ +	[83] [41] [44]	Breakwater AR In situ concrete test
Proteobacteria		+	[83]	Breakwater
Bacteroidetes		+ +	[83] [44]	Breakwater In situ concrete test
Anaerolinea		+	[94]	Yangtze river reservoir
Polynucleobacter		+	[94]	Yangtze river reservoir
Sulfate-reducers		+	[94]	Yangtze river reservoir
Ammonia-oxidizers Nitrosopumilus sp		+ +	[94] [86]	Yangtze river reservoir Ammonia-oxidizing archaea. Oslofjord undersea tunnel
Desulfobacteria Desulfobacterales		+ + +	[114] [44] [86]	Sulfate reducers In situ concrete test Sulfate reducers. Oslofjord undersea tunnel
Firmicutes		+ +	[114] [44]	Tidal areas. Phylum includes sulfur bacteria. May produce endospores In situ concrete test
Acidobacteria		+	[44]	In situ concrete test. Acid-producers
Chloroflexi		+	[44]	In situ concrete test Heterophototrophic filamentous bacteria
Nitrospina, Nitrospira		+	[86]	Nitrite-oxidizing bacteria. Oslofjord undersea tunnel
Nitrosomonas		+	[86]	Anoxic ammonia oxidisers. Oslofjord undersea tunnel
Scalindua		+	[86]	Anammox bacteria. Oslofjord undersea tunnel
Mariprofundus		+	[86]	Stalked iron-oxidising bacteria. Oslofjord undersea tunnel
Ponticaulus	+		[40]	Archaea In vitro study
Hyphomonas	+		[40]	Stalked bacteria. In vitro study
Planctomycetales	+ +	+	[40] [41] [44]	In vitro study. Budding bacteria AR In situ concrete test
Rhodobacterales	+		[40]	Primary marine surface colonizers. In vitro study
Caulobacteriales	+		[40]	In vitro study. Stalked bacteria
Portibacter	+		[40]	In vitro study. Bacteroidetes.
Bacillus (Firmicutes)	+		[115]	Bridge
Brachybacterium	+		[115]	Bridge
Flavobacterium	+		[115]	Bridge
Lysinibacillus	+		[115]	Bridge
Thiomonas perometabolis	+		[115]	Bridge. Sulfur oxidizer
Propiogenium	+		[41]	AR Anaerobe
Vibrio	+		[41]	AR
Clostridium	*		[41]	AR Anaerobe
Fusobacteria	+		[41]	AR Anaerobes
Actinobacteria	+	+	[41] 1[44]	AR In situ concrete test

AR = artificial reef.

2.2.1. Microbial adhesion and biofilm development

Biodeterioration of concrete in the marine environment begins with microorganisms adhering to its surface, forming a biofilm. The alkaline nature of new concrete inhibits the activity of microorganisms [44], but the pH falls rapidly under the wetting and leaching influence of the marine environment, whose pH is generally between 7.5 and 9 [45], enabling microbial adhesion and metabolic activity. [46], in laboratory experiments, clearly demonstrated the effect of reducing the surface pH of concrete samples on the rate of microbial adhesion from seawater. The first colonizers are bacteria, which can themselves produce acid metabolites that further reduce pH and increase susceptibility of the concrete surface to microbial attack. The earliest studies concentrated on concrete corrosion in sewers by acid producing bacteria [47], but more recent studies have determined the effects of concrete structure and composition on general bacterial adhesion (e.g., [48]; [49]; [46]; [40]). The effect of surface roughness of the substratum on biofilm formation has been shown to influence the types of bacteria initially adhering to immersed materials [49], although it has been suggested that this may not be very important for particles as small as bacteria adhering to concrete [50]. The presence of reinforcing rods within the concrete has a much greater effect than rugosity [40]. The last cited authors found that bacterial groups with increased adherence on reinforced concrete included members of the family Magnetospiraceae and the genera Portibacter, Rubripirellula, and Rhodopirellula; these are not particularly associated with a requirement for iron, although Magnetospiraceae have been found in Fe-Mn deposits [51] and Portibacter in iron slags in marine situations [52]. It is likely that metal ions from within the corroding concrete can reach the surface and become available to bacteria in the surrounding seawater. Iron is an important nutrient for bacterial cells and, as a component of certain natural stones, may act as an attractant for adhering microorganisms [53].

[40] found that Ponticaulus sp. and Hyphomonas sp. were two of the most abundant bacterial genera in early biofilms on concrete in seawater, and suggested that they are pioneer organisms, which are later outgrown by other genera. These two genera have been found to play important roles in biofilm formation on steel in the marine environment [54]. [39], after a series of experiments to assess the effects of different stone substrata (including concrete) on marine biofilm formation, similarly concluded that the biofilms converged over time to a generic marine type, and that the underlying substrata did not play a significant role in community composition. Where the substrata are basically similar, as in this case where they were all types of natural or artificial stone, this may be true, but there are certainly differences between the biofilm-formers on very different substrates in seawater, such as concrete and wood, for example [55].

The initial attachment of cells to the concrete surface leads to the up-regulation of bacterial genes that code for the production of extracellular polymeric substances (EPS), which strengthen the attachment and encourage the adhesion of circulating cells and other materials. EPS are diverse, including not only polysaccharides, the principal component, but also proteins, nucleic acids, and lipids [56]; their potential effects on concrete are varied and complex. Cactus polymer, for example, has been used in Mexico to improve the properties of Portland cement [57] and, along with bacterial EPS, to consolidate limestone surfaces [58]. Bacterial EPS can be used to improve the viscosity and cohesion of concrete [59]. On the other hand, the EPS-containing biofilm is a stable environment for microbial cells, enabling them to remain active and attached to the concrete surface and minimizing the loss of corrosive metabolites [60]. There is considerable information on EPS, their make-up, production and effects [61]; [62]; [63]; [64]; [65]; [66]; [56]) and this will not be further detailed here. Their production plays a part in the development of a complex biofilm, which eventually leads to the adherence of higher organisms, the readily visible “marine biofouling”, sometimes called “hard fouling” because of the presence of shell-bearing animals such as barnacles and oysters; this final stage in the marine fouling process is not within the remit of the current article.

2.2.2. Concrete corroding microorganisms and mechanisms

Although the initial bacterial biofilm on seawater-immersed concrete may have little immediate effect on its structure, it encourages adhesion and growth of further microorganisms, many of which may have corrosive activity.

2.2.2.1. Organic acid producing microorganisms.

Many heterotrophic bacteria, such as Vibrio, Acidobacteria, Bacillus, produce organic acids during their metabolism. Organic acids attack the concrete, causing decalcification of hydration products, which leads to higher inherent porosity and cracking [67]. They are also produced by fungi, although these filamentous microorganisms are less common in the marine environment. Indeed, [68] discuss whether fungi are, in fact, metabolically active in seawater, pointing out that many of them are parasitic on other living creatures. They emphasize that DNA sequencing techniques for fungi in general are underdeveloped, explaining, at least in part, why so few marine fungi have been described. [69] state that most marine fungi are saprobes that rely on the high levels of organic matter generally found in coastal environments. Whether fungi in the open sea are potentially corrosive is debatable. Nevertheless, many terrestrial fungi produce organic acids and, if active in saltwater and sediments, will be capable of concrete deterioration.

Direct evidence for the fungal decay of concrete, then, is missing, although there is no doubt that these microorganisms have the metabolic capacity to produce corrosive compounds [70] and recent genomic and metabolomic analyses have demonstrated that at least one marine fungal species (Emericellopsis cladophorae, associated with marine algae) has the genetic capacity to produce carbohydrate-active enzymes under saline conditions [71]. [72] suggested that a Fusarium species isolated from degraded concrete along with Thiobacillus could be responsible for more rapid degradation than the bacteria. [73] reported a fungus (Fusarium oxysporum) as being responsible for the corrosion of 3 concrete bridges over the River Nile, but only the presence of the fungus was reported and there was no direct evidence of its involvement in the corrosion process. Other workers have reported the isolation of microorganisms from corroded concrete that were deemed unlikely to be involved in biodeterioration (e.g., [74]). Nevertheless, there is some evidence that fungi, simply by their acid producing metabolism, may be able to corrode concrete under certain conditions [75]. [76] selected 3 fungi previously shown to grow on concrete surfaces, although not underwater, to test a nanosilica coating as a protective layer on concrete. When incubated with control uncoated concrete blocks in a fungal growth medium, all caused weight loss after 3 months. The most destructive fungus was Aspergillus tamarii, a fungus isolated originally from historic buildings in Havana. [70] discuss in detail the potential of fungi to cause concrete corrosion, although they do not cite any definitive cases of such corrosion in the marine environment.

2.2.2.2. Inorganic acid producing bacteria

Autotrophs can produce inorganic (mineral) acids, which are more corrosive than organic acids. These include nitrifying bacteria, such as Nitrosomonas and Nitrobacter, which produce nitric acid [77]; [78], and sulfur oxidizing bacteria (SOB) Thiobacillus, Thiothrix, Thiomicrospira, Beggiatoa, etc [78]; [79]. The latter group produces sulfuric acid that reacts with concrete to form gypsum, which has poor structural properties. This is considered to be the main concrete corrosion process in sewers, often in conjunction with the anaerobic, heterotrophic sulfate-reducing bacteria (SRB), such as the genera Desulfovibrio and Desulfomicrobium, which, under low oxygen conditions, reduce the sulfate in seawater to sulfides that can then be converted to corrosive sulfuric acids by the SOB [80]. SRB are mainly, but not exclusively, anaerobic bacteria and would be active in the marine environment either in sediments or beneath biofilms. [81] give a detailed description of SRB corrosion in concrete sewers.

Heterotrophic (organic carbon-utilizing) bacteria produce a variety of organic acids during metabolism and growth. A very wide variety of bacterial species with this ability are found in seawater and their concrete corroding ability cannot be ignored, although there is little published evidence relating to specific genera and species.

The potential, specifically corrosive nature of the microorganisms detected in immersed concrete biofilms is noted, where relevant, in Table 1.

2.3. Influence of seawater exposure regime on concrete biofilm formation

Oxygen is a critical component in determining the growth of microorganisms. Those found in well oxygenated waters are very different from the facultative or obligate anaerobes that can adsorb to surfaces at lower depths. Our review of the literature has not yielded well constructed experiments that allow direct comparisons of permanently and intermittently immersed concrete. The perfect set-up would be similar to that employed by [82], who studied the corrosion of a concrete beam exposed for 7 years to atmospheric, splash, tidal and submerged zones around Qingdao Wheat Island, China. Unfortunately, they did not include biofilm formation in their study, although they did report that barnacles were only found in the tidal zone and oysters in the submerged zone. Comparison between these types of concrete immersion in seawater must rely, therefore, on published case histories, with no possibilities of citing controlled experiments, or even paired results.

2.3.1. Concrete in the submerged zone

Permanently immersed concrete may avoid strong corrosion if the seawater is sufficiently low in oxygen, although microorganisms active at low oxygen levels may still produce aggressive compounds [83]; [84]; [85]; [86]. In less deep waters, sufficient oxygen may still be present to allow chemical corrosion and certainly biological activity will be present, with its associated dangers. Figure 1 shows a concrete slope in a small dock; the black biofilm in the splash zone is very different from the green, submerged zone film containing photosynthetic cyanobacteria and algae.

Apart from concrete structures such as oil storage tanks associated with offshore oil platforms, underwater tunnels and foundations, this section also includes laboratory and in situ simulations aimed at determining parameters involved in concrete biocorrosion, testing protective processes and evaluating new types of concrete. Even when such experimental pieces are subjected to the real marine environment in situ, they are normally kept completely immersed for the required time (e.g., [87]; [88]). The laboratory tests almost always involve complete immersion of test pieces in natural or artificial seawater; they are often inoculated with single microorganisms and in this case do not represent real conditions. Nevertheless, we are including in this article references to studies where conditions are sufficiently similar to those in vivo, as examples of biodeterioration of permanently immersed concrete.

[89], for example, used a laboratory system to demonstrate the effect of dissolved oxygen on concrete corrosion by sulfur-oxidizing bacteria added to seawater; lower dissolved oxygen levels resulted in reduced bacterial growth and less corrosion.

[90], similarly in vitro, showed that the marine benthic diatom, Cylindrotheca closterium, was able to liberate and utilize silicon from a cementitious mortar. The diatom utilized the Si to produce new frustule material during cell division. Diatoms have often been shown to deposit on immersed concrete; indeed, [91] suggested that diatoms adhered to a recycled concrete surface could offer increased durability and demonstrated increased water resistance in laboratory experiments.

[40] reported controlled experiments to determine the formation of biofilms on concrete of similar composition to that of the Oslofjord subsea tunnel, which had shown deterioration at sites where saline groundwater had intruded in previous investigations [92]. At this earlier time, the group had demonstrated the presence of ammonia- and nitrite-oxidizing microorganisms, in particular Nitrosopumilus sp., and iron-oxidizing bacteria within the Mariprofundus sp., as well as various heterotrophic bacteria and archaea at these tunnel sites. However, this microbial population will have included organisms from groundwater, as well as marine bacteria. In their later investigations [40], they incubated in water from the fjord concretes of similar composition to those in the tunnel. The fjord water was filtered (50um), kept in the dark and recirculated to ensure oxygen saturation during incubation with the concrete samples, which were removed at intervals over 65 weeks. Bacteria and archaea in the concrete and seawater samples were analyzed using DNA analysis. The microbial populations in the thin biofilms on the concrete were significantly different from those in the seawater, even though both populations were composed of typical marine genera, and changed with time. Different concrete compositions showed different colonization patterns during the first weeks, but these differences tended to even out, suggesting a replacement of initially adhering microorganisms with more generic concrete colonizers, as also suggested by [39]. No special acid-producing genera were detected in the sessile populations, although calcium was removed from the concrete surfaces, indicating corrosion. However, metabolomic studies indicated that the mixed acid fermentation pathway was common in the biofilm.

[40] on microorganisms present in the biofilms, along with results from other articles on seawater and rare, but interesting, freshwater situations, are included in Table 1.

2.3.2. Concrete in the splash and tidal zones

Artificial shoreline structures such as piers, reefs, seawalls, embankments and jetties are common in developed coastal regions and serve as examples of intermittently immersed concrete which are also, incidentally, often steeply inclined. Obviously, the more steeply inclined the concrete, the less time it will spend covered in water. As noted in the section on chemical concrete corrosion, the splash zone is most affected by the corrosive action of seawater constituents plus oxygen from the atmosphere. However, simple observation indicates that this is not the zone most affected by biodeterioration (Figure 2 and Figure 3).

Figure 2 demonstrates intense corrosion and biofilm formation on a vertical concrete structure in Campeche, Mexico.

Figure 2. Intertidal concrete structures such as the base of this fisherman’s house, built over a rocky shore, exhibit a heterogeneous coverage of microorganisms. Lerma village, Campeche, Mexico.

Figure 2. Intertidal concrete structures such as the base of this fisherman’s house, built over a rocky shore, exhibit a heterogeneous coverage of microorganisms. Lerma village, Campeche, Mexico.

The intertidal zone shows deep pits and cracks in the concrete, associated with dark biofilms, while the splash zone above demonstrates black/green biofilms, but without the intense corrosion of the intertidal zone. It is possible that the microbiological colonization has protected this area from the normally more intense chemical corrosion that occurs in the splash zone. Alternatively, it may be the greater wave impact at the wall base that is at least partially responsible for greater physical degradation.

A similar, but less intense, situation can be seen in Figure 3. Here, corrosion (surface spalling) of the concrete in the more inclined splash zone can be seen, but the intertidal zone is covered by a dark gray/black biofilm, with associated, relatively light, biodegradation.

Figure 3. Biofilms covering concrete surfaces often exhibit a black phenotype indicating the likely presence of scytonemin-producing cyanobacteria as a functional adaptation for water stress and excessive insolation. San Francisco de Campeche city, Campeche, Mexico. .

Figure 3. Biofilms covering concrete surfaces often exhibit a black phenotype indicating the likely presence of scytonemin-producing cyanobacteria as a functional adaptation for water stress and excessive insolation. San Francisco de Campeche city, Campeche, Mexico. .

[93] found that bacterial biofilms colonizing breakwaters along an island coast were dominated by Cyanobacteria, Proteobacteria and Bacteroidetes.They were different from the planktonic bacteria at the same locations, as shown by [40].

Although not normally in contact with seawater, reservoirs are associated with various concrete structures, such as walls, gate piers and slopes, that are only intermittently immersed in water and could give an indication of concrete colonizers on intermittently-immersed structures. [94] studied the bacterial communities at various points on 4 reservoirs in the Yangtze River basin, using Miseq DNA sequencing. Proteobacteria, Cyanobacteria and Chloroflexi were the major colonizers, with most common groups being Leptolyngbya, Anaerolineaceae, and Polynuceobacter. The concrete gate piers had the highest proportion of sulfate-reducing bacteria and were considered at highest risk, although ammonia-oxidisers were also predominant.

A recent report of the presence of metagenomes associated with anammox (ammonium oxidizing) bacteria in water seepages on the concrete inner surface of the Subsea Oslofjord tunnel [95] is the first indication that these as yet unisolated anaerobes could be involved in deepsea concrete corrosion. Anammox bacteria are associated with biofilms that can lead to localized acidification [96]. Nitrifying bacterial markers (Nitrosomonas, Nitrosopumilus, Nitrospirales and Nitrospirota) were also detected at the site. Once leaked into the tunnel, (the equivalent of a splash zone) the higher oxygen environment would allow the production of inorganic nitrogen acids, encouraging concrete corrosion.

3. Interactions of chemistry and microbiology in concrete degradation - some speculations

4. Artificial reefs: a special case.

5. Conclusions and perspectives

References

1. Scrivener, K.L.; Snellings, R. The rise of Portland cements. Elements. 2022, 18, 308-313.
2. Jahren, P.; Sui, T. History of Concrete: A Very Old and Modern Material. World Scientific, Singapore, 2017. [CrossRef]
3. Monteiro, P.J.; Kirchheim, A.P.; Chae, S.; Fischer, P.; MacDowell, A.A.; Schaible, E.; Wenk, H.R. Characterizing the nano and micro structure of concrete to improve its durability. Cem Concr Comp. 2009. 31, 577-584. [CrossRef]
4. Wenk, H.R.; Lutterotti, L.; Vogel, S. Texture analysis with the new HIPPO TOF diffractometer. Nucl Instrum Methods Phys Res. 2003, 515, 575-588. [CrossRef]
5. Han, X.; Wang, B.; Feng, J. Relationship between fractal feature and compressive strength of concrete based on MIP. Construct Build Mats. 2022, 322, 126504. [CrossRef]
6. Wang, L.; Yu, Z.; Liu, B.; Zhao, F.; Tang, S.; Jin, M. Effects of fly ash dosage on shrinkage, crack resistance and fractal characteristics of face slab concrete. Fractal Fract. 2022, 6, 335. [CrossRef]
7. Ahmad, J.; González-Lezcano, R.A., Majdi, A.; Ben Kahla, N.; Deifalla, A.F.; El-Shorbagy, M.A. Glass fibers reinforced concrete: overview on mechanical, durability and microstructure analysis. Materials. 2022, 15, 5111. [CrossRef]
8. Wang, R.; Hu, Z.; Li, Y.; Wang, K.; Zhang, H., 2022b. Review on the deterioration and approaches to enhance the durability of concrete in the freeze–thaw environment. Construct Build Mats. 2022, 321, 126371. [CrossRef]
9. Xiao, J.; Zhang, K.; Ding, T.; Zhang, Q.; Xiao, X. Fundamental issues towards unified design theory of recycled and natural aggregate concrete components. Eng J. 2023, . [CrossRef]
10. Torres, A.; Simoni, M.U.; Keiding, J.K.; Müller, D.B.; zu Ermgassen, S.O.; Liu, J.; Jaeger, J.A.; Winter, M.; Lambin, E.F. Sustainability of the global sand system in the Anthropocene. One Earth. 2021, 4, 639-650. [CrossRef]
11. Mehta PK. Concrete in the marine environment. CRC Press. 1991. [CrossRef]
12. Qu, F.; Li, W.; Dong, W.; Tam, V.W.; Yu, T. Durability deterioration of concrete under marine environment from material to structure: A critical review. J Build Eng. 2021, 35, 102074. [CrossRef]
13. Becker, L.R.; Ehrenberg, A.; Feldrappe, V.; Kröncke, I.; Bischof, K. The role of artificial material for benthic communities–establishing different concrete materials as hard bottom environments. Mar Environ Res. 2020, 161, 105081. [CrossRef]
14. Bone, J.R.; Stafford, R.; Hall, A.E.; Herbert, R.J. Biodeterioration and bioprotection of concrete assets in the coastal environment. Int Biodeter Biodegr, 2022, 175, 105507. [CrossRef]
15. Scott, P.J.B.; Moser, K.A.; Risk, M.J. Bioerosion of concrete and limestone by marine organisms: A 13-year experiment from Jamaica. Mar Poll Bull. 1988, 19, 219-222. [CrossRef]
16. Richmond, M.D.; Seed, R., 1991. A review of marine macrofouling communities with special reference to animal fouling. Biofouling. 1991, 3, 151-168. [CrossRef]
17. Hughes, P.; Fairhurst, D.; Sherrington, I.; Renevier, N.; Morton, L.H.G.; Robery, P.C.; Cunningham, L. Microscopic study into biodeterioration of marine concrete. Int Biodeter Biodegr. 2013, 79,14-19. [CrossRef]
18. Hopkins, G.; Davidson, I.; Georgiades, E.; Floerl, O.; Morrisey, D.; Cahill, P. Managing biofouling on submerged static artificial structures in the marine environment–assessment of current and emerging approaches. Front Mar Sci. 2021, 8, 759194. [CrossRef]
19. Vuong, P.; McKinley, A.; Kaur, P. Understanding biofouling and contaminant accretion on submerged marine structures. npj Mater Degrad. 2023, 7, 50. [CrossRef]
20. Lambert, P.; Page, C.L.; Short, N.R. Pore solution chemistry of the hydrated system tricalcium silicate/sodium chloride/water. Cement Concr Res. 1985, 15, 675-680. [CrossRef]
21. Yu, L.; Chu, H.; Zhu, Z.; Jiang, L.; Dong, H. Determination of the chloride ion content in concrete under simultaneous chloride and sulphate ion attack. J Build Eng. 2023, 72, 106579. [CrossRef]
22. Yi, Y.; Zhu, D.; Guo, S.; Zhang, Z.; Shi, C. A review on the deterioration and approaches to enhance the durability of concrete in the marine environment. Cement Concrete Comp. 2020, 113, 103695. [CrossRef]
23. Balestra, C.E.T.; Reichert, T.A.; Savaris, G. Contribution for durability studies based on chloride profiles analysis of real marine structures in different marine aggressive zones. Construct Build Mats. 2019, 206, 140-150. [CrossRef]
24. Islam, M.S.; Mondal, B.C.; Islam, M.M. Effect of sea salts on structural concrete in a tidal environment. Austral J Struct Eng. 2010, 10, 237-252, . [CrossRef]
25. Wu, L.; Li, W; Yu, X. Time-dependent chloride penetration in concrete in marine environments. Construct Build Mats. 2017, 152, 406-413. [CrossRef]
26. Wang, Y.; Guo, S.; Yan, B.; Liu, Z.; Wang, Y.; Yuan, C. Experimental and analytical investigation on chloride ions transport in concrete considering the effect of dry-exposure ratio under diurnal tidal environment. Construct Build Mats. 2022, 328,127138. [CrossRef]
27. Rahman, R.O.A.; Ojovan, M.I. Sustainability of cementitious structures, systems, and components (SSC’s): Long-term environmental stressors. In Sustainability of life cycle management for nuclear cementation-based technologies, 1^st ed; Rehab O. Abdel Rahman, Michael I. Ojovan, Eds.; Woodhead Publishing, 2021, pp. 181-232. [CrossRef]
28. Iqbal, P.O.N.; Ishida, T. Modeling of chloride transport coupled with enhanced moisture conductivity in concrete exposed to marine environment. Cement Concr Res. 2009, 39, pp. 329-339. [CrossRef]
29. Kwon, S.J.; Lee, H.S.; Karthick, S.; Saraswathy, V.; Yang, H.M. Long-term corrosion performance of blended cement concrete in the marine environment–A real-time study. Constr Build Mats. 2017, 154, 349-360. [CrossRef]
30. Andrade, C.; Dı́ez, J.M.; Alonso, C. Mathematical modeling of a concrete surface “skin effect” on diffusion in chloride contaminated media. Adv Cement Based Mats. 1997, 6, 39-44. [CrossRef]
31. Qiao, X.; Chen, J. Correlation of propagation rate of corrosive crack in concrete under sulfate attack and growth rate of delayed ettringite. Eng Fract Mech. 2019, 209, 333-343. [CrossRef]
32. Lv, H.; Chen, J.; Lu, C. A Statistical Evolution Model of Concrete Damage Induced by Seawater Corrosion. Materials. 2021, 14, 1007. [CrossRef]
33. Ting, M.Z.Y.; Yi, Y. Durability of cementitious materials in seawater environment: A review on chemical interactions, hardened-state properties and environmental factors. Construct Build Mats. 2023, 367,130224. [CrossRef]
34. Chaudhari, B.; Panda, B.; Šavija, B.; Chandra-Paul, S. Microbiologically Induced Concrete Corrosion: A Concise Review of Assessment Methods, Effects, and Corrosion-Resistant Coating Materials. Materials. 2022, 15, 4279. [CrossRef]
35. Anwar, A.; Liu, X.; Zhang, L. Biogenic corrosion of cementitious composite in wastewater sewerage system-A review. Proc Safety Environ Protect. 2022. [CrossRef]
36. Li, X.; Jiang, G.; Grengg, C.; Mittermayr, F. Mechanisms and Processes of Concrete Corrosion in Sewers. In Microbiologically Influenced Corrosion of Concrete Sewers, 1^st ed.; Jiang, G.; Ed; Springer, Cham, 2023; pp. 21-34. [CrossRef]
37. Ragab, A.M.; Elgammal, M.A.; Hodhod, O.A.; Ahmed, T.E. Evaluation of field concrete deterioration under real conditions of seawater attack. Construct Build Mats. 2016, 119, 130-144. [CrossRef]
38. Zettler, E.R.; Mincer, T.J.; Amaral-Zettler, L.A. Life in the “plastisphere”: microbial communities on plastic marine debris. Environ Sci Technol. 2013, 47, 7137-7146. [CrossRef]
39. Summers, S.; Pek, Y.S.; Vinod, D.P.; McDougald, D.; Todd, P.A.; Birch, W.R.; Rice, S.A. Bacterial biofilm colonization and succession in tropical marine waters are similar across different types of stone materials used in seawall construction. Front Microbiol. 2022, 13, 928877. [CrossRef]
40. Karačić, S.; Modin, O.; Hagelia, P.; Persson, F.; Wilén, B.M. The effect of time and surface type on the composition of biofilm communities on concrete exposed to seawater. Int Biodeter Biodegr. 2022, 173, 105458. [CrossRef]
41. Mohamed, H.F.; Abd-Elgawad, A.; Cai, R.; Luo, Z.; Pie, L.; Xu, C. Microbial community shift on artificial biological reef structures (ABRs) deployed in the South China Sea. Sci Rep. 2023, 13, 3456. [CrossRef]
42. Vincke, E.; Boon, N.; Verstraete, W. Analysis of the microbial communities on corroded concrete sewer pipes – a case study. Appl Microbiol Biotechnol. 2001, 57, 776–785. [CrossRef]
43. Tong, X.; Leung, M.H.; Shen, Z.; Lee, J.Y.; Mason, C.E.; Lee, P.K. Metagenomic insights into the microbial communities of inert and oligotrophic outdoor pier surfaces of a coastal city. Microbiome. 2021, 9, 1-15. [CrossRef]
44. Li, X.; Li, S.; Huang, X.; Chen, Y.; Cheng, J.; Zhan, A. Protein-mediated bioadhesion in marine organisms: a review. Mar Environ Res. 2021, 170, 105409. [CrossRef]
45. Halevy, I.; Bachan, A. The geologic history of seawater pH. Science. 2017, 355, 1069–1071, . [CrossRef]
46. Hayek, M.; Salgues, M.; Habouzit, F.; Bayle, S.; Souche, J.C.; De Weerdt, K.; Pioch, S. In vitro and in situ tests to evaluate the bacterial colonization of cementitious materials in the marine environment. Cement Concrete Comp. 2020, 113, 103748. [CrossRef]
47. Parker, C.D. Species of sulphur bacteria associated with the corrosion of concrete. Nature, 1947, 159, pp.439-440. [CrossRef]
48. Dang, H.; Lovell, C.R. Microbial surface colonization and biofilm development in marine environments. Microbiol Molec Biol Revs. 2016, 80, 91-138. [CrossRef]
49. Caruso, G. Microbial colonization in marine environments: overview of current knowledge and emerging research topics. J Mar Sci Eng. 2020, 8, 78. [CrossRef]
50. Voegel, C.; Durban, N.; Bertron, A.; Landon, Y.; Erable, B. Evaluation of microbial proliferation on cementitious materials exposed to biogas systems. Env Technol. 2020, 41, 2439-2449. [CrossRef]
51. Bergo, N.M.; Torres-Ballesteros, A.; Signori, C.N.; Benites, M.; Jovane, L.; Murton, B.J.; da Rocha, U.N.; Pellizari, V.H. Spatial patterns of microbial diversity in Fe-Mn deposits and associated sediments in the Atlantic and Pacific oceans. Sci Total Environ. 2022, 837, 155792. [CrossRef]
52. Ogawa, A.; Tanaka, R.; Hirai, N.; Ochiai, T.; Ohashi, R.; Fujimoto, K.; Akatsuka, Y.; Suzuki, M. Investigation of biofilms formed on steelmaking slags in marine environments for water depuration. Int J Mol Sci. 2020, 21, 6945. [CrossRef]
53. Gaylarde, C.; Little, B. Biodeterioration of stone and metal—Fundamental microbial cycling processes with spatial and temporal scale differences. Sci Total Environ. 2022, 153193. [CrossRef]
54. Procópio, L. Microbial community profiles grown on 1020 carbon steel surfaces in seawater-isolated microcosm. Ann Microbiol. 2020, 70, 13. [CrossRef]
55. Guo, Z.; Wang, L.; Cong, W.; Jiang, Z.; Liang, Z. Comparative analysis of the ecological succession of microbial communities on two artificial reef materials. Microorganisms. 2021, 9, 120. [CrossRef]
56. Flemming, H.C.; van Hullebusch, E.D.; Neu, T.R.; Nielsen, P.H.; Seviour, T.; Stoodley, P.; Wingender, J.; Wuertz, S. The biofilm matrix: Multitasking in a shared space. Nature Revs Microbiol. 2023, 21, 70-86. [CrossRef]
57. Chandra, S.; Eklund, L.; Villarreal, R.R. Use of cactus in mortars and concrete. Cement Concr Res. 1998, 28, 41-51. [CrossRef]
58. Camacho-Chab, J.C.; Pereañez-Sacarías, J.E.; Camacho-Chab, P.A.; Gaylarde, C.; Arena-Ortiz, M.L.; Ortiz-Alcántara, J.M.; Chan-Bacab, M.J.; Quintana-Owen, P.; Ortega-Morales, B.O. Influence of bacterial biopolymers on physical properties of experimental limestone blocks. World J Microbiol Biotechnol. 2022, 38, 254. [CrossRef]
59. Cano-Barrita, P.D.J.; León-Martínez, F.M. Biopolymers with viscosity-enhancing properties for concrete. In Biopolymers and biotech admixtures for eco-efficient construction materials, 1^st ed.; Fernando Pacheco-Torgal, Volodymyr Ivanov, Niranjan Karak, Henk Jonkers, Eds; Woodhead Publishing, 2016; pp. 221-252. [CrossRef]
60. Rong, H.; Zhang, S.; Ma, G.; Zheng, X.; Qian, C.; Zhang, L.; Zhang, Y.; Xu, R. Formation, growth and corrosion effect of sulfur oxidizing bacteria biofilm on mortar. Constr Build Mats. 2021, 268, 121218. [CrossRef]
61. Rodrigues, C.; Bhosle, N.B. Exopolysaccharide production by Vibrio fischeri, a fouling marine bacterium, Biofouling. 1991, 4, 301-308, . [CrossRef]
62. Callow, M.E.; Callow, J.A. Marine biofouling: a sticky problem. Biologist. 2002, 49, pp. 1-5.
63. Poli, A.; Anzelmo, G.; Nicolaus, B. Bacterial exopolysaccharides from extreme marine habitats: Production, characterization and biological activities. Marine Drugs. 2010, 8, 1779-1802. [CrossRef]
64. Rajitha, K.; Nancharaiah, Y.V.; Venugopalan, V.P. Role of bacterial biofilms and their EPS on settlement of barnacle (Amphibalanus reticulatus) larvae. Int Biodeter Biodegr. 2020, 150, 104958. [CrossRef]
65. Wang, Y.; Zhang, R.; Duan, J.; Shi, X.; Zhang, Y.; Guan, F.; Sand, W.; Hou, B. Extracellular polymeric substances and biocorrosion/biofouling: recent advances and future perspectives. Int J Molec Sci. 2022, 23, 5566. [CrossRef]
66. Ma, W.; Wang, X.; Zhang, W.; Hu, X.; Yang, J.L.; Liang, X. Two-Component system response regulator ompR regulates mussel settlement through exopolysaccharides. Int J Molec Sci. 2023, 24, 7474. [CrossRef]
67. Ninan, C.M.; Ajay, A.; Ramaswamy, K.P.; Thomas, A.V.; Bertron, A. A critical review on the effect of organic acids on cement-based materials. In IOP Conference Series: Earth Environ Sci. 2020, 491, 012045. [CrossRef]
68. Gladfelter, A.S.; James, T.Y.; Amend, A.S. Marine fungi. Curr Biol. 2019, 29, R191-R195. [CrossRef]
69. Jones, E.G.; Ramakrishna, S.; Vikineswary, S.; Das, D.; Bahkali, A.H.; Guo, S.Y.; Pang, K.L. How do fungi survive in the sea and respond to climate change? Journal of Fungi. 2022, 8, 291. [CrossRef]
70. Jiang, L.; Pettitt, T.R.; Buenfeld, N.; Smith, S.R. A critical review of the physiological, ecological, physical and chemical factors influencing the microbial degradation of concrete by fungi. Build Environ. 2022, 108925. [CrossRef]
71. Gonçalves, M.F.; Hilário, S.; Van de Peer, Y.; Esteves, A.C.; Alves, A. Genomic and metabolomic analyses of the marine fungus Emericellopsis cladophorae: insights into saltwater adaptability mechanisms and its biosynthetic potential. J Fungi, 2022, 8, 31. [CrossRef]
72. Gu, J.D.; Ford, T.E.; Berke, N.S.; Mitchell, R. Biodeterioration of concrete by the fungus Fusarium. Int Biodeterior Biodeg. 1998, 41, 101-109. [CrossRef]
73. Geweely, N.S.I. Evaluation of ozone for preventing fungal influenced corrosion of reinforced concrete bridges over the River Nile, Egypt. Biodegradation. 2011, 22, 243–252. [CrossRef]
74. Nica, D.; Davis, J.L.; Kirby, L.; Zuo, G.; Roberts, D.J. Isolation and characterization of microorganisms involved in the biodeterioration of concrete in sewers. Int Biodeter Biodeg. 2000, 46, 61-68. [CrossRef]
75. De Windt, L.; Devillers, P. Modeling the degradation of Portland cement pastes by biogenic organic acids. Cem Concr Res. 2010, 40, 1165-1174. [CrossRef]
76. 66. Bhattacharyya, S.; Akhtar, S.; Chaudhuri, A.; Mahanty, S.; Chaudhuri, P.; Sudarshan, M. Affirmative nanosilica mediated approach against fungal biodeterioration of concrete materials. Case Stud Construc Mats. 2022, 17, e01258. [CrossRef]
77. Diercks, M.; Sand, W.; Bock, E. Microbial corrosion of concrete. Experientia. 1991, 47, 514–516. [CrossRef]
78. Sand, W.; Bock, E., 1990. Biodeterioration of concrete by thiobacilli and nitrifying bacteria. Matériaux & Techniques. 1990, 78, 70-72. [CrossRef]
79. Yousefi, A., Allahverdi, A. and Hejazi, P. Accelerated biodegradation of cured cement paste by Thiobacillus species under simulation condition. Int Biodeter Biodegr, 2014, 86, 317-326. [CrossRef]
80. Zhou, J.; Yin, S.; Fu, Q.; Wang, Q.; Huang, Q.; Wang, J. Microbial-induced concrete corrosion under high-salt conditions: Microbial community composition and environmental multivariate association analysis. Int Biodeter Biodegr. 2021, 164, 105287. [CrossRef]
81. Rooyackers, F.A.; Bosco, E.; Suiker, A.S.; Clemens, F.H. A chemo-mechanical model for biogenic sulphide corrosion of concrete. Cement Concr Res, 2022, 160, 106809. [CrossRef]
82. Li, S.; Jin, Z.; Pang, B.; Li, J. Durability performance of an RC beam under real marine all corrosion zones exposure for 7 years. Case Studies in Constr Mats. 2022, 17, e01516. [CrossRef]
83. Huang, S.P.; Chen, T.Y.; Chen, J.S.; Wang, L.T.; Huang, L.; Lin, S.T.; Wei, C.L.; Lin, S.; Wang, P.L.; Chen, Y.M.; Shieh, W.Y. Dongshaea marina gen. nov., sp. nov., a facultatively anaerobic marine bacterium that ferments glucose with gas production. Int J Systemat Evolut Microbiol. 2019, 69, 3318-3325. [CrossRef]
84. Pelikan, C.; Wasmund, K.; Glombitza, C.; Hausmann, B.; Herbold, C.W.; Flieder, M.; Loy, A. Anaerobic bacterial degradation of protein and lipid macromolecules in subarctic marine sediment. The ISME J. 2021, 15, 833-847. [CrossRef]
85. Fincker, M.; Huber, J.A.; Orphan, V.J.; Rappé, M.S.; Teske, A.; Spormann, A.M. Metabolic strategies of marine subseafloor Chloroflexi inferred from genome reconstructions. Environ Microbiol. 2020, 22, 3188-3204. [CrossRef]
86. Ding, W.; Wang, S.; Qin, P.; Fan, S.; Su, X.; Cai, P.; Lu, J.; Cui, H.; Wang, M.; Shu, Y.; Wang, Y. Anaerobic thiosulfate oxidation by the Roseobacter group is prevalent in marine biofilms. Nature Commun. 2023, 14, 2033. [CrossRef]
87. Georges, M.; Bourguiba, A.; Chateigner, D.; Sebaibi, N.; Boutouil, M. The study of long-term durability and bio-colonization of concrete in marine environment. Environ Sustain Indicators. 2021, 10, 100120. [CrossRef]
88. Rong, H.; Chen, X.; Feng, Y.; Zhang, Y.; Zhang, J. Adhesion of biofilm to mortar surface with protective coating in seawater environment and the influence on the mortar performance. Journal of Mats Civil Eng. 2023, 35, 04023016. [CrossRef]
89. Sun, M.; Xu, W.; Rong, H.; Chen, J.; Yu, C. Effects of dissolved oxygen (DO) in seawater on microbial corrosion of concrete: Morphology, composition, compression analysis and transportation evaluation. Construct Build Mats. 2023, 367, 130290. [CrossRef]
90. Georges, M.; Bourguiba, A.; Boutouil, M.; Chateigner, D.; Jolly, O.; Claquin, P. Interaction between the diatom Cylindrotheca closterium and a siliceous mortar in a silica-limited environment. Const Build Mats. 2022, 321, 126277. [CrossRef]
91. Merino-Maldonado, D.; Antolín-Rodríguez, A.; Serrano-González, L.; Blanco, S.; Juan-Valdés, A.; Morán-del Pozo, J.M.; García-González, J. Innovative approach for the protection of recycled concrete by biogenic silica biodeposition. Constr Build Mats. 2023, 368, 130475. [CrossRef]
92. Karačić, S.; Wilén, B.M.; Suarez, C.; Hagelia, P.; Persson, F. Subsea tunnel reinforced sprayed concrete subjected to deterioration harbours distinct microbial communities. Biofouling. 2018, 34, 1161-1174. [CrossRef]
93. Li, K.; Guan, W.; He, P.; Li, K.J. Comparison of bacterial communities on the surface of concrete breakwater structures and ambient bacterioplankton. Letts Appl Microbiol. 2022, 75, 1193-1202. [CrossRef]
94. Cai, W.; Li, Y.; Niu, L.; Zhang, W.; Wang, C.; Wang, P.; Meng, F. New insights into the spatial variability of biofilm communities and potentially negative bacterial groups in hydraulic concrete structures. Water Research. 2017, 123, 495-504. [CrossRef]
95. Suarez, C.; Dalcin Martins, P.; Jetten, M.S.; Karačić, S.; Wilén, B.M.; Modin, O.; Hagelia, P.; Hermansson, M.; Persson, F. Metagenomic evidence of a novel family of anammox bacteria in a subsea environment. Environ Microbiol. 2022, 24, pp.2348-2360. [CrossRef]
96. Karačić, S. Microbial biofilm communities associated with degradation of sprayed concrete in subsea tunnels, Doctoral thesis, Chalmers Tekniska Hogskola (Sweden), 2021. https://www.researchgate.net/profile/Sabina-Suceska-Karacic/publication/356732212_Microbial_biofilm_communities_associated_with_degradation_of_sprayed_concrete_in_subsea_tunnels/links/61a9561aca2d401f27be3899/Microbial-biofilm-communities-associated-with-degradation-of-sprayed-concrete-in-subsea-tunnels.pdf Accessed on 27th June, 2023.
97. Yu, C.; Yuan, Q.; Rong, H.; Liu, D.; Feng, Y. Effects of dissolved oxygen on marine biofilm formation and its on microstructure and chloride ion permeability of concrete. Journal of Building Engineering. 2023, 75, 107074. [CrossRef]
98. Ertelt, M.J.; Raith, M.; Eisinger, J.; Grosse, C.U.; Lieleg, O. Bacterial Additives Improve the Water Resistance of Mortar. ACS Sustain Chem Eng. 2020, 8, 5704-5715. [CrossRef]
99. Wang, J.; Yin, S.; Lu, L.; Zhou, J.; Fu, Q. Characterization of microbial-induced concrete corrosion by combining morphology observation and fluorescence staining. Case Stud Constr Mater. 2022, 17, e01586. [CrossRef]
100. Chung, H.; Lee, O.; Huang, Y.L.; Mok, S.Y.; Qian, P.Y. Bacterial community succession and chemical profiles of subtidal biofilms in relation to larval settlement of the polychaete Hydroides elegans. ISME J. 2010, 4, 817–828. [CrossRef]
101. Salta, M.; Wharton, J.A.; Blache, Y.; Stokes, K.R.; Briand, J.F. Marine biofilms on artificial surfaces: structure and dynamics. Environ microbial. 2013, 15, 2879-2893. [CrossRef]
102. Qian, P.Y.; Cheng, A.; Wang, R.; Zhang, R. Marine biofilms: diversity, interactions and biofouling. Nat Rev Microbiol. 2022, 20, 671-684. [CrossRef]
103. Kundukad, B.; Ho, J.C.; Mugunthan, S.; Wong, L.L.; Rice, S.A.; Parikh, A.N.; Seviour, T.; Hinks, J.; Kjelleberg, S. Viewing biofilm formation through a multifocal lens of physics and biology. Microbiology Aust. 2023, 44, 69-74. [CrossRef]
104. Davis, J.; Levin, L.; Walther, S. Artificial armored shorelines: sites for open-coast species in a southern California bay. Mar Biol. 2002, 140, 1249-1262. [CrossRef]
105. Miller, M.W. Using ecological processes to advance artificial reef goals. ICES J Mar Sci, 2002, 59, S27-S31. [CrossRef]
106. Ramm, L.A.; Florisson, J.H.; Watts, S.L.; Becker, A.; Tweedley, J.R. Artificial reefs in the Anthropocene: a review of geographical and historical trends in their design, purpose, and monitoring. Bull Mar Sci, 2021, 97, 699-728. [CrossRef]
107. Ly, O.; Yoris-Nobile, A.I.; Sebaibi, N.; Blanco-Fernandez, E.; Boutouil, M.; Castro-Fresno, D.; Hall, A.E.; Herbert, R.J.; Deboucha, W.; Reis, B.; Franco, J.N. Optimisation of 3D printed concrete for artificial reefs: Biofouling and mechanical analysis. Constr Build Mats. 2021, 272, 121649. [CrossRef]
108. Kong, J.; Cong, G.; Ni, S.; Sun, J.; Guo, C.; Chen, M.; Quan, H. Recycling of waste oyster shell and recycled aggregate in the porous ecological concrete used for artificial reefs. Constr Build Mats, 2022, 323, 126447. [CrossRef]
109. Berman, O.; Weizman, M.; Oren, A.; Neri, R.; Parnas, H.; Shashar, N.; Tarazi, E. Design and application of a novel 3D printing method for bio-inspired artificial reefs. Ecol Eng. 2023, 188, 106892. [CrossRef]
110. Salamone, A.L.; Robicheau, B.M.; Walker, A.K. Fungal diversity of marine biofilms on artificial reefs in the north-central Gulf of Mexico. Botan Mar. 2016, 59, 291-305. [CrossRef]
111. Tong, F.; Chen, G.; Feng, X.; Liu, Y.; Chen, P. The effect of the artificial reef on the structure and function of sediment bacterial community. Sustain. 2022, 14, 14728. [CrossRef]
112. Xiong, Y.; Tang, L.; Jia, H.; Shao, C.; Tang, J.; Xu, Y.; Yan, L.; Zhang, D. Microbial networks reveal the structure of water microbial communities in Kalamaili Mountain Ungulate Nature Reserve. Water, 2022, 14, 2188. [CrossRef]
113. Cooke, S.J.; Bergman, J.N.; Nyboer, E.A.; Reid, A.J.; Gallagher, A.J.; Hammerschlag, N.; Van de Riet, K.; Vermaire, J.C. Overcoming the concrete conquest of aquatic ecosystems. Biol Conserv. 2020, 247, 108589. [CrossRef]
114. Li, S.; Liu, J.; Geng, Y.; Liu, A.; Xu, A.; Hou, D.; Lang, X. Efficacy and mechanism of GO/IBTS coating against microbial fouling of concrete surfaces in marine tidal areas. JCTR. 2022, 19, 875-885. [CrossRef]
115. Trejo, D.; de Figueiredo, P.; Sanchez, M.; Gonzalez, C.; Wei, S.; Li, L. Analysis and assessment of microbial biofilm-mediated concrete deterioration. Technical Report, U.S. Department of Transportation, 2008.