Woodpile Research Articles

Culturing erosion bacteria: Procedures for obtaining purer cultures and pure strains

This paper describes procedures used in attempts to isolate pure strains of erosion bacteria from bacterial consortia obtained from decaying wood. The wood originated from archaeological waterlogged wood and foundation pilings. Kapok fibres were used as a substitute for wood in most experiments. Erosion bacteria attached firmly to the surface of kapok fibres and to cellophane. Intense washing of these substrates resulted in active cultures with a reduced number of associated secondary bacteria. This was not achieved with common dilution techniques. Pure strains obtained from streaking on cellulose or nutrient agar failed to attack kapok fibres and pine wood. Single erosion bacteria cells were separated from secondary bacteria by using laser techniques (optical tweezers). Molecular analyses of the most purified culture, obtained through washing of cellophane, and of laser separated bacteria, suggested that erosion bacteria belong to the CFB ( Cytophaga- Flavobacterium- Bacteroides) complex.

First observations on bryozoans and entoprocts in the Ria de Aveiro (NW Portugal) including the first record of the Pacific invasive cheilostome Tricellaria inopinata

The results of a survey on bryozoans and entoprocts in the Ria de Aveiro (NW Portugal) are presented. The Ria de Aveiro is a coastal lagoon hosting large port facilities and several tourist marinas, thus presenting a wide variety of submerged structures and consequently a rich fouling community. In June and July 2004, 10 stations were selected and biological samples were collected from hard substrates such as wooden piles and floating pontoons. The identification to species level revealed the presence of 2 entoprocts and 16 bryozoans (5 ctenostomes and 11 cheilostomes). The most common species are Bowerbankia gracilis (found in all stations), Cryptosula pallasiana and Bugula neritina (found in 8 and 9 out of 10 stations, respectively). Noteworthy is the occurrence of Tricellaria inopinata; it is well established in several sites of the two investigated channels and even becomes dominant in the Canal de Ovar. This cheilostome bryozoan is an alien species of Pacific origin, first introduced to Europe in the lagoon of Venice (Italy); this record in the Ria de Aveiro is the first one for Portuguese coasts. The case of T. inopinata has been studied in the lagoon of Venice as a meaningful example of bryozoan biodiversity loss related to the spread of alien species due to aquaculture activity and/or shipping (commercial vessels). The Ria de Aveiro, with its important port and tourist marinas, constitutes an ideal site for the development of alien species’ propagules and a source for secondary dispersal; thus, improved monitoring of its fouling community could be useful to control and prevent the dispersal of non-native biota.

Adaptive roadside sampling for bark beetle damage assessment

Bark beetle infestations are often scattered throughout the forest landscape and therefore difficult to accurately and rapidly assess. We tested a roadside sampling technique in a pure maritime pine forest ( Pinus pinaster) of ca. 1300 ha where bark beetle outbreak foci were observed following a windstorm. The sampling method relied on the count along stand edges of all dying or dead trees sighted within a fixed distance from the road. About 2300 trees attacked by Ips sexdentatus were recorded and located using colour-infrared aerial photography. Accuracy of the infestation map was verified by ground sampling. Piles of cut logs stored along the edge significantly increased the percentage of attacked trees in the neighbouring stand. However, the percentage of attacked trees within the stand edges did not differ with the percentage within the stand interior. It allowed us to use stand edges as sampling units to estimate the mean percentage of attacked trees per stand. At the stand scale, the use of a fixed 10 m wide strip along stand edges maximized the detection of attacked trees and minimized the bias of estimated percent of attacked trees. Based on GIS data, various stratified roadside sampling plans with increasing numbers of edges per stand and increasing numbers of stands per forest were simulated by bootstrap resampling. In a forest without any storage of cut logs, systematic roadside surveys underestimated the level of damage. The sampling accuracy increased with the kilometers of edges surveyed. In a forest with piles of cut logs on which bark beetles can breed, the best option was an adaptive sampling plan where at least two additional consecutive edges were observed in stands close to the pile. As compared to systematic sampling plans, adaptive plans were three times less expensive in terms of sampling effort for the same accuracy. Overall, adaptive sampling plans were also more robust as they provided less biased estimates as the proportion of stands with nearby piles increased in simulated forests.

POSTFIRE RESPONSE OF FLOOD-REGENERATING RIPARIAN VEGETATION IN A SEMI-ARID LANDSCAPE

Piles of large wood (LW) deposited by major floods in river corridors can interact with naturally occurring wildfires from uplands to impact the regeneration of riparian vegetation. This study examines the spatial and short-term temporal response of riparian vegetation and soil nutrients to fire along the Sabie River, South Africa, with special emphasis on the effects of burned LW piles. At the study site there were 112 species of plants recorded with 28% of species restricted to the burned plots. As expected, vegetation cover was significantly lower in burned plots as compared with the unburned plots 12 months postfire. There was a significant influence of LW on species richness with fewer species recorded in the LW plots. For both fire and LW treatments, plant cover showed a significant change over three years. After an initial increase from 12 to 24 months (postfire) there was a decline in plant cover after 36 months. Species community composition was distinctly different between burned and unburned plots 12 months postfire, and the presence of LW affected species composition for burned plots but not for unburned ones. Time series ordination of LW plots highlighted the changes in species composition over the three years of sampling. Of trees with accumulations of LW within 5 m of their base, 48% had been killed by fire as compared to only 4% with no LW accumulations in close proximity. Soil-available P was significantly higher in the burned plots and even higher with burned LW while there were no effects on soil total N. There was also a significant positive trend between available P in soils and plant vegetation cover. Soil-exchangeable K was also significantly higher and total C significantly lower in the burned and LW plots. Burned plots also had significantly higher soil electrical conductivity (EC) and soil pH. The patchy nature of the studied fire, whose complexity is exacerbated by the distribution of flood deposited LW, acted to create a mosaic of alternate successional states as the riparian community recovers from flooding and the subsequent fire. We suspect that the resultant heterogeneity will increase ecosystem resilience by providing flexibility in the form of more options for a system response to subsequent disturbances.

Porifera and Bryozoa on artificial hard bottoms in the Venice Lagoon: Spatial distribution and temporal changes in the northern basin

The spatial distribution and temporal changes of demosponges and bryozoans in the northern basin of the Venice Lagoon were studied from samples collected from wooden piles and artificial rocks in June and October 2001. Twenty species of demosponges and 18 species of bryozoans were recorded. Sponges were found at 10 out of 11 sampling stations, while bryozoans were found at all 11 sampling stations. The studied taxocoenoses showed a high percentage cover of the lagoon hard bottoms. Eleven out of the 20 detected species of sponges were reported in a previous study on this taxocoenosis carried out on material collected in 1954–1955. Moreover, the most abundant species were also recorded during a study in 1989. These observations suggest a remarkable degree of persistence of the sponge community. Among bryozoans, the comparison with literature data showed a wider variation in species composition, with the occurrence of five new species in the studied area. The Indo‐Pacific invasive Tricellaria inopinata replaced the native Bugula spp. in the role of dominant species. Finally, a significant increase in species richness along the salinity gradient, more evident for sponges than for bryozoans, was identified.

Patterns of winter locomotion and foraging in two sympatric marten species:Martes martesandMartes foina

Modes of area searching and exploratory behaviour of the sympatric pine marten, Martes martes (L., 1758), and stone marten, Martes foina (Erxleben, 1777), were studied by snow-tracking in two regions of Poland. The accuracy of identifications of the two species on the basis of their snow tracks was assessed by DNA analysis of their faeces, as collected on the tracks; identifications were found to be correct in 88% of cases. Although most activities of the two species were concentrated on the forest floor, pine martens climbed trees, moved in tree crowns, and searched the bases of tree trunks and tree hollows more frequently than stone martens. In contrast, stone martens were more inclined to search for food in brushwood and piles of wood, and visited logged areas and garbage dumps more frequently. Pine martens avoided man-made objects and barriers such as roads and passed through open areas with reluctance. Such behavioural traits make this species particularly vulnerable to forest fragmentation and human activity in forests. Stone martens often explored woodless areas and inhabited buildings, which allowed them to use habitats substantially transformed and intensively explored by humans. The future coexistence and relative numbers of the two martens in forest habitats will depend on the mode of forest management and on the existence of effective migratory corridors connecting forest patches.

Kirmenjak- Pietra d'Istria : a preliminary investigation of its use in Venetian architectural heritage

Abstract Kirmenjak — white limestone from the quarries near the village of Kirmenjak in Istria (Croatia), in the past known as Pietra d'Istria — has been regularly used in the construction of the basal zone of Venetian buildings since the 14th century. Its characteristics — durability, extremely low water absorption and high compressive strength — made it an ideal material for the lowest parts of Venetian buildings in the zone between foundation (wooden piles) and brick walls. In this zone, exposed to tidal flooding and low-tide drying, materials deteriorate very quickly, but Kirmenjak has proved to be durable even in this aggressive saline environment. Moreover, this dense micritic or pelmicritic stylolitized limestone from the Upper Jurassic (Tithonian) was used as an efficient barrier to rising damp. Preliminary in situ investigation of how Kirmenjak blocks were laid shows that the prevalent stylolite orientation is horizontal in the basal parts of buildings, while in other structural elements this orientation varies. This inspired the hypothesis that the Venetian constructors took advantage of horizontally laid stylolite discontinuities (partially filled with clay) as a multilayer humidity barrier.

Lessons from Modeling Sudoku in Excel

In a previous paper, Chlond [Chlond, M. J. 2005. Classroom exercises in IP modeling: Sudoku and the log pile. INFORMS Trans. Ed. 5(2), http://ite.pubs.informs.org/Vol5No2/Chlond/ (last accessed on May 11, 2006)] presented the formulation of Sudoku as an integer program. Chlond claims that a spreadsheet formulation is not straightforward but we present a simple Excel formulation. In light of the current use of Excel in the classroom it can be highly instructive to formulate the problem using Excel. In addition, the formulation of this relatively simple model enables instructors to introduce students to the capability of programming Solver using VBA. In a follow-on paper (Rasmussen and Weiss [Rasmussen, R. A., H. J. Weiss. 2007. Advanced lessons on the craft of optimization modeling based on modeling sudoku in excel. INFORMS Trans. Ed. To appear]), we demonstrate advanced lessons that can be learned from using Premium Solver's powerful features to model Sudoku.

First record of the rare gall midge Tribremia brevitarsis (Diptera, Cecidomyiidae) from Slovakia

During investigations of entomofauna associated with canes of plants from the genus Rubus in SW Slovakia, adults of a very rare gall midge species Tribremia brevitarsis (Kieffer, 1904) (Diptera, Cecidomyiidae) were found and identified. Adults of T. brevitarsis were found resting on slight cobwebs stretched inside loganberry (Rubus loganobaccus L.) stand. This is the first record of this species after its description by KIEFFER (1904). Adults of T. brevitarsis are very small flies. The body of the male is 1.9 mm long and wing 2.2 mm; the body of the female is 1.8 mm long and wing 2.2 mm. Antennae of both sexes are 2 + 12 segmented. Male flagellomeres are binodal, each flagellomere with two unequal nodes; the proximal node is ovoid, the distal node is pear-shaped. Female flagellomeres are cylindrical and each flagellomere consists of only one node and a short stem. Biology of this species is unknown. KIEFFER (1904) caught a single male on a pile of wood in July and described it as Bremia brevitarsis. Later KIEFFER (1912) established the new genus Tribremia (without giving diagnosis) with Bremia brevitarsis as the type species. A year later KIEFFER (1913) gave a complete diagnosis of this genus and figured the hypopygium of the male. Material examined: SW Slovakia, Vrable (48◦15′ N, 18◦17′ E, 172 m a.s.l.), 5 , 1 , 14.VIII.2005, adults were caught inside the stand of Rubus loganobaccus, leg. P. Toth, det. et coll. M. Skuhrava. Distribution: France and Slovakia. This species was found by KIEFFER (1904) in environs of Bitch in NE France and since 1904 has not been recorded in any country till 2005 when it was found at Vrable in SW Slovakia. It is a very rare species (SKUHRAVA et al., 2005).

Assessment of the Integrity of Piles by Impedance Log Technique

The objective of this paper is to investigate the capabilities of the Impedance Log method in profiling the geometry of a pile along its length. The main idea of this method is to introduce a transient stress wave into the pile and then utilize the reflected signals to obtain the impedance profile of the pile. Any anomaly, which results in changes in impedance, would be detected by this method. In this study, four model piles with plan defects of weak zone or neck were constructed and tested using Seismic Echo, Impulse Response, and Impedance Log pile integrity nondestructive testing methods. Results of these tests show that interpretation of signals using the Impedance Log method is more straightforward than the other two methods. It is concluded that the Impedance Log technique is a tool with high potential for evaluating the integrity of piles.

Impact of Aspen Log Storage with and without Protection on OSB Performance

Outdoor log storage without protection can change the mechanical and chemical properties of wood due to infection by various fungi. To understand how outdoor log storage affects the wood and, subsequently, the strandboard quality, two piles of aspen logs were set up outside and stored for a period of four months (July to November). One of the piles was treated with a biological solution to prevent fungal growth. The other one was stored without treatment. Both piles contained non-debarked and partially debarked logs. Evaluation of sap stain development indicated that all logs had been colonized by staining fungi with average stain coverage of 9.37 to 57.18% and maximum stain penetration of 3.58 to 7.27 cm over the log cross section. The variation of fungal colonization depended on log treatment and bark condition. The most effective way to prevent stain growth was the combination of biological treatment and partial debarking. A series of strandboard was prepared from fresh and aged aspen logs. All boards made from stored logs were statistically comparable to or superior to the control boards made from fresh aspen logs. The boards made from treated/partially debarked and untreated/non-debarked logs were statistically comparable to each other except for wet MOR. In addition, these two board types were statistically stronger than other boards made from treated/non-debarked and untreated/partially debarked logs in terms of IB and water resistance. Some individual stained strands were observed on the finished board surface. Less staining was found in the boards prepared from biologically treated and partially debarked logs, compared with those made from other stored logs.

Flood‐deposited wood creates regeneration niches for riparian vegetation on a semi‐arid South African river

AbstractQuestion: The formation of large woody debris (LWD) piles during floods has significant impacts on riparian succession through pioneering plants often establishing in association with wood. We assess the importance of LWD for seed regeneration of riparian plants after a century‐scale flood disturbance in a semi‐arid environment.Location: The Sabie River within Kruger National Park in the semi‐arid northeast of South Africa.Methods: Our approach was to quantify the riparian soil seed bank, to record the frequency of establishment of riparian plants in woody debris piles, and to conduct experimental out‐plantings of common riparian trees in plots with and without LWD.Results: We found the abundance and diversity of seedlings were higher in soils taken from wood piles than from open reference areas, and most seedlings were herbaceous species. Surveys indicated that numbers of seedlings recorded within woody debris were significantly greater than in open reference areas or within established vegetation. Seedling establishment in various cover‐types also varied for different riparian tree species. Experimental out‐planting of seedlings of two riparian tree species (Philenoptera violacea and Combretum erythrophyllum) revealed that, after 433 days, planted seedlings survived only in woody debris piles.Conclusion: LWD formed after a large flood creates heterogeneous patches that may influence post‐disturbance regeneration of riparian vegetation by providing a variety of environmental niches for seedlings establishment. We suspect that higher seedling survival in LWD is due to increased moisture (particularly in the dry season) and nutrients, and protection from seasonal flooding and herbivory.

Formation, distribution and ecological consequences of flood-related wood debris piles in a bedrock confined river in semi-arid South Africa

The Sabie River, located within the semi-arid savanna of South Africa, experienced a ∼100-year return interval flood in 2000, providing a rare opportunity to quantify the resultant pattern and consequence of woody debris piles for riparian areas. Biophysical attributes of rivers in arid and semi-arid regions differ strongly from those in mesic regions, but differences in the role and dynamics of woody debris remain largely unknown. Our primary goal was to determine the basic ecology and distribution of wood piles formed by a large infrequent flood in a bedrock-confined river. In particular, we sought to determine the mechanism of pile formation, their position, size, and structural attributes of piles as well as regeneration from resprouting and seedling recruitment within piles in different channel types. We observed relatively distinct patterns of distribution and mechanisms of formation in 421 piles and provide a description of the distribution, abundance and short-term fate of each pile type. Patterns of wood accumulation were largely controlled by characteristics of the trapping sites, particularly toppled trees that remain rooted in their growth location. In general, wood was primarily strewn against toppled, transported and standing trees, though several large piles formed on bedrock outcrops. Buried piles were also discovered upon excavation of depositional features (alluvial mounds). Resprouting of toppled trees with intact roots and living tissues was the dominant mode of vegetation reestablishment in the piles. We observed resprouting in 36% of piles surveyed. Resprouting piles were most common (48%) in the seasonally inundated portion of the macro-channel. Tree seedlings were recorded in 28% of the piles. The flood appeared to create heterogeneity in the establishment of new woody vegetation by forming distinct wood piles from the ruins of the previous riparian forest. Even though the input of wood to semi-arid rivers appears to be a fairly rare occurrence and wood piles are rapidly depleted by decay and fire, we expect their influence will be long-lived, preserved in the pattern of vegetation establishment and alluvial mounds within the macro-channel. Copyright © 2006 John Wiley & Sons, Ltd.

Possibility of utilization of wood as a countermeasure of global warming

To address the problem of the global warming, using a lot of wood and making a forest active are one of the problems to be solved. Utilization of wood has a long history and wood piles had been used as a foundation of structure until around 1950 in Japan. After the 1950's, the amount of cement and steel production dramatically increased instead of wood. Reconsideration of how the wood can be used for construction would therefore be one of the countermeasures of global warming for the future. However, since one of the reasons for not using the wood as a foundation of structure these days is decay, investigation for the decay of wood as a foundation of structure should be carried out. For this reason, an investigation of a dug up wood pile which was used as a fence for 26 years in Iwamizawa city in Hokkaido is carried out.

Flood-deposited wood creates regeneration niches for riparian vegetation on a semi-arid South African river

Question: The formation of large woody debris (LWD) piles during floods has significant impacts on riparian succession through pioneering plants often establishing in association with wood. We assess the importance of LWD for seed regeneration of riparian plants after a century-scale flood disturbance in a semi-arid environment. Location: The Sabie River within Kruger National Park in the semi-arid northeast of South Africa. Methods: Our approach was to quantify the riparian soil seed bank, to record the frequency of establishment of riparian plants in woody debris piles, and to conduct experimental outplantings of common riparian trees in plots with and without LWD. Results: We found the abundance and diversity of seedlings were higher in soils taken from wood piles than from open reference areas, and most seedlings were herbaceous species. Surveys indicated that numbers of seedlings recorded within woody debris were significantly greater than in open reference areas or within established vegetation. Seedling establishment in various cover-types also varied for different riparian tree species. Experimental out-planting of seedlings of two riparian tree species (Philenoptera violacea and Combretum erythrophyllum) revealed that, after 433 days, planted seedlings survived only in woody debris piles. Conclusion: LWD formed after a large flood creates heterogeneous patches that may influence post-disturbance regeneration of riparian vegetation by providing a variety of environmental niches for seedlings establishment. We suspect that higher seedling survival in LWD is due to increased moisture (particularly in the dry season) and nutrients, and protection from seasonal flooding and herbivory.

A fuzzy logic model to recognise ecological sectors in the lagoon of Venice based on the benthic community

The lagoon of Venice is a mosaic resulting from the interaction of several biotic and abiotic factors. A qualitative scheme of such a mosaic was proposed in literature; it subdivided the lagoon into six ecological sectors (“lagoon mouths”, “vivified lagoon”, “rough eutrophic”, “calm eutrophic”, “urban”, “estuarine”), related with current velocity, salinity, eutrophication and pollution, and expressed by means of the sessile macrobenthos living on wooden piles. In this paper, we present the conversion of that scheme into a fuzzy logic model, which considers four input variables: abundance of marine species; abundance of lagoon species; abundance of oligohaline species and total abundance of the sessile macrozoobenthos. Three fuzzy sets describe abundance levels ( low, medium, high) for each one of the four variables; the 81 (3 4) resulting combinations have been associated to the six ecological sectors, for a total of 486 “if … then” rules. We have used two different interpretations of the inference process, and combined their results with the “crisp weighting” technique to obtain the fuzzy membership grades to the six ecological sectors. The model, built on data from the lagoon of Venice in 1993–1994, has been validated with more recent data from the same stations and from the nearby lagoon of Grado-Marano; the results are in agreement with the literature information.

A survey on Triatoma dimidiata in an urban area of the province of Heredia, Costa Rica

Triatoma dimidiata has been found in several cities and towns of those countries where the insect is a domestic or peridomestic pest. In Central America, urban infestations occur in the capitals of at least five countries. During 2001 and 2002 a survey was carried out in the county of San Rafael, Heredia province, located 15 km northwest of San José, capital of Costa Rica, in order to determine the degree of infestation by T. dimidiata in an entire city block. Six peridomestic colonies of the insect were detected in the backyards of eight households. The ecotopes occupied by the insects consisted of store rooms with old objects, wood piles or firewood, and chicken coops. A total of 1917 insects were found in the six foci, during two sampling periods, and a mean infection rate by Trypanosoma cruzi of 28.4% was found in 1718 insects examined. The largest colony found in one of the households yielded 872 insects that were thriving mainly at the expenses of two dogs. Opossums and adult insects were common visitors of the houses and it became evident that this marsupial is closely related to the peridomestic cycle of the Chagas disease agent. Lack of colonization of the insect inside the human dwellings is explained by the type of construction and good sanitary conditions of the houses, in contrast to the situation in most peridomiciliary areas. Stomach blood samples from the insects showed that the main hosts were, in order of decreasing frequency: rodents, dogs, fowl, humans, opossums, and cats. The fact that no indication of infection with Chagas disease could be detected in the human occupants of the infested houses, vis a vis the high infection rate in dogs, is discussed.

Spatiotemporal patterns of reinfestation by Triatoma guasayana (Hemiptera: Reduviidae) in a rural community of northwestern Argentina.

Triatoma guasayana (Wygodzinsky & Abalos) is a secondary vector of Trypanosoma cruzi (Chagas), the etiologic agent of Chagas disease, in the Chaco region of Argentina, Bolivia, and Paraguay. The spatial distribution of T. guasayana in a rural community in northwestern Argentina is described and analyzed using very high spatial resolution satellite imagery, geographic information systems, and spatial statistics. Since a 1992 residual spraying with insecticides of all houses, site-specific domestic and peridomestic reinfestations by triatomine bugs were monitored using various methods semiannually from 1993 to 2002. The reinfestation by T. guasayana started with finding of only adult bugs in a few sites. Bug abundance was significantly clustered and predominantly peridomestic in the southern and northern extremes of the community. The identified source of reinfestation in the northern cluster was a colonized wood pile, whereas no potential peridomestic source was found for the southern cluster. The spatial distribution of T. guasayana was positively associated with the abundance and spatial distribution of goats. Active dispersal from the hypothesized source and the surrounding sylvatic environment, and passive transport of bugs in wood piles seems to be the most likely mechanisms underlying the observed spatial pattern of T. guasayana. The absence of domestic colonization indicates that, to date, there is no trend toward increased local domiciliation of T. guasayana. The clustering zones can be considered "hot spots" where bug invasion from other sources is expected to be higher and where eventually, introduction of sylvatic T. cruzi to suitable hosts may occur.

Spatiotemporal Patterns of Reinfestation by <I>Triatoma guasayana</I> (Hemiptera: Reduviidae) in a Rural Community of Northwestern Argentina

Triatoma guasayana (Wygodzinsky & Abalos) is a secondary vector of Trypanosoma cruzi (Chagas), the etiologic agent of Chagas disease, in the Chaco region of Argentina, Bolivia, and Paraguay. The spatial distribution of T. guasayana in a rural community in northwestern Argentina is described and analyzed using very high spatial resolution satellite imagery, geographic information systems, and spatial statistics. Since a 1992 residual spraying with insecticides of all houses, site-specific domestic and peridomestic reinfestations by triatomine bugs were monitored using various methods semiannually from 1993 to 2002. The reinfestation by T. guasayana started with finding of only adult bugs in a few sites. Bug abundance was significantly clustered and predominantly peridomestic in the southern and northern extremes of the community. The identified source of reinfestation in the northern cluster was a colonized wood pile, whereas no potential peridomestic source was found for the southern cluster. The spatial distribution of T. guasayana was positively associated with the abundance and spatial distribution of goats. Active dispersal from the hypothesized source and the surrounding sylvatic environment, and passive transport of bugs in wood piles seems to be the most likely mechanisms underlying the observed spatial pattern of T. guasayana. The absence of domestic colonization indicates that, to date, there is no trend toward increased local domiciliation of T. guasayana. The clustering zones can be considered "hot spots" where bug invasion from other sources is expected to be higher and where eventually, introduction of sylvatic T. cruzi to suitable hosts may occur.

Repair of Wood Piles Using Prefabricated Fiber-Reinforced Polymer Composite Shells

An effective method for combined environmental protection and structural restoration of wood piles in waterfront facilities is not available. The objective of the study presented in this paper is to survey the available methods for wood pile protection and structural restoration with the intent of developing an effective method. In addition to reviewing the available repair methods, a field inspection of a harbor in Maine was conducted to assess existing technologies. A wood pile repair method that utilizes bonded fiber-reinforced polymer (FRP) composite shells and a grouting material is proposed. Fiber, resin, adhesive, coating, and grouting materials are systematically analyzed to deliver the required system performance. Two fabrication methods for the FRP composite shells are discussed based on the experience gained in the fabrication of laboratory prototypes. Then a step-by-step procedure amenable for field installation is proposed, and a preliminary cost analysis is conducted to assess the feasibility of the proposed system.