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In order to address water damage of asphalt pavement, reduce the occurrence of water-related potholes, deformation, and other diseases, and improve the performance and service life of the pavement, a nano-TiO2 superhydrophobic coating (PSC) on asphalt pavement was prepared from waterborne polyurethane and nano-TiO2 modified by stearic acid. FT-IR measured stearic acid successfully modified low surface energy substance on the surface of nano-TiO2. The SEM image shows that the PSC has a rough surface structure. The contact angle and rolling angle of the PSC in the contact angle test are 153.5&deg, and 4.7&deg, respectively. PSC has a super-hydrophobic ability, which can improve the water stability of the asphalt mixture. Although the texture depth and pendulum value have been reduced by 2.5% and 4.4%, respectively, they all comply with the standard requirements. After the abrasion resistance test, the PSC coating still has a certain hydrophobic ability. These results surface PSC coating can effectively reduce water damage on asphalt pavement, and has considerable application value.

Water transport in dense-graded asphalt mixtures (DGAMs) is one significant topic for an in-depth study of water damage in asphalt pavements. The X-ray computed tomography (X-ray CT) helps researchers to understand the internal structure of DGAMs and restructure it for numerical simulations of water transport in DGAMs. This review discusses the difference between the internal structure of DGAMs’ specimens by laboratory compactions, which include the Superpave gyratory compactor (SGC), the linear kneading compactor (LKC), the Marshall compactor and the vibratory compactor, and field cores and clarifies the purpose of a laboratory compaction. And then the review describes gaseous and liquid water transport in DGAMs, the permeability of three transport media, asphalt mixtures, asphalt mastic and pure asphalt. Numerical simulations of DGAMs are also discussed in the review and confronted problems are set forth that involve the dividing of the gray threshold in X-ray CT images, the restructuring of the 3D model of DGAMs, the permeability of asphalt mastic in this model and the truncation criterion of a water transport process. Future work on water transport in DGAMs is recommended in the end of the review.

Several studies have shown an association between dampness and health issues like headache and asthma. To better understand the exposure risk of fungal growth in buildings this study investigates the release of fungi from gypsum boards infested with fungi from a moisture-damaged house. Further, the composition and concentration of fungal species in indoor air of five non-moisture-damaged homes are analysed, and the ratio between species associated- and not associated with moisture-damaged buildings are related to air change rate (ACR) and relative humidity (RH). The air velocity near the surface of the gypsum boards in combination with the changes in sampling time influenced the particle release rate. After 8 h particles were still released, and more species were released during 8 h with low air velocity than during 15 min with high air velocity. More fungal species and a higher release rate were found from damp surfaces with substantial growth than from gypsum boards dried out before they were totally colonized. In the five homes ACR and RH had a significant influence on the fungal species composition. Thus, a low ACR and a high RH were associated with increased ratio of species associated with moisture-damage relative to species not associated with moisture-damage. In conclusion, increasing the ventilation and reducing the RH of the indoor air will have a beneficial effect on the airborne species composition. Further, fast action by drying out a fungal infestation has a positive impact on the exposure risk in terms of exposure level and species composition.

Purpose – The water damage in buildings because of leaking pipes and increasingly because of floods and severe weather require professional help. Methods for improved repair and remediation techniques have to be developed. The water damage in buildings because of leaking pipes and increasingly because of floods and severe weather require professional help. Methods for improved repair and remediation techniques have to be developed. The paper aims to discuss these issues. Design/methodology/approach – Therefore, large scale laboratory tests with four rooms, each with three types of masonry walls (Figure 2 and Plate 1) and typical floors for intermediate storeys with insulation were performed within a climate simulator. Artificial water damage was provoked through watering the floors, and the dispersion of water in the floors and the rising damp in the walls was measured. In the follow-up to the watering of the floors, a company specialized in drying wet buildings, installed systems for under floor drying and wall drying. Findings – The drying process of the different components and layers of the floor construction and walls was monitored by a measuring system with more than 300 sensors for moisture content, relative humidity and temperature accompanied by thermography and demonstrated so the advantages and disadvantages of the different tested drying systems. After providing an initial contamination that is typical for construction sites, the microbial load (mould infestation) within the wet components was monitored at different times by experienced biologists. So after three weeks under floor drying no mould growth could be asserted but more bacteria than expected were found. Originality/value – The aim of the research was to gain more confidence in selecting appropriate drying procedures and systems in order to identify the right moment for terminating the drying process. A further intent was to acquire data for computer simulations.

The reduction of both environmental problems and construction costs has motivated the asphalt pavement industry to increasingly use waste materials as alternative raw materials in road pavements construction. This investigation aims to explore the potential of waste calcium carbide residue (CCR) for use as a filler in hot mix asphalt (HMA), by substituting traditional limestone filler in various proportions. Asphalt mixes were prepared using different CCR ratios (0%, 3% and 6%) by aggregate dry weight, their strength, properties and performance evaluated against the indirect tensile stiffness modulus, rutting, crack initiation, crack propagation and moisture damage. The results show that stiffness modulus and resistance to permanent deformation and cracks have been enhanced due to the addition of CCR. HMA modified with CCR was also found to be less sensitive to water damage than traditional HMA with limestone filler. A toxicity characteristic leaching procedure (TCLP) test revealed that the CCR used in the production of HMA has no environmental impact. Therefore, based on this study, CCR can be considered as a plausible alternative to conventional filler in HMA, the implication being that large amounts of waste carbide lime can be removed from landfill, thereby significantly reducing environmental damage.

Earth building is experiencing a renaissance due to the emerging recognition of the damage the construction industry is doing to the global environment. Research over the past three decades has identified the hygroscopic nature of these materials, and our understanding of the factors governing their hydromechanical properties is now mature. However, little work has been done to unify methods to assess material durability: namely, how exposure to degrading agents, predominantly water, impacts a structure’s service life. Although strength is usually of primary concern to engineers, it is undeniable that earthen structures usually fail due to durability, rather than strength, issues. As earthen architecture and demands made of the material become more ambitious, the need for robust guidelines on how to predict the longevity of these structures becomes paramount. This paper presents a framework for assessing the durability of earthen materials based on perceived routes of exposure to water. The framework is built upon the findings of a review of nearly 60 articles discussing original durability testing programmes, comprising 118 investigations and almost 700 soil and stabiliser combinations. From these works, 12 assessment methodologies were identified, encompassing a range of earthen construction techniques, e.g. mud brick, compressed earth blocks and rammed earth. Each method is described and its suitability for assessing the real world durability of a range of earthen construction techniques appraised. From this, the efficacy of each test was determined and a shortlist of suitable tests created. The derived framework provides assessors with a method to determine likely exposure routes for an earthen construction element (e.g. an internal or external wall) and, from the shortlisted methods, to specify the range of tests necessary to ensure suitable durability given the construction and environmental conditions. This work forms part of the update to the Standards Australia Earth Building Handbook: SA HB 195.

Wind-driven rain (WDR) is one of the most important causes for water damage in buildings. Therefore, the first crucial step to assess the hygrothermal performance of the building envelope, is the appropriate estimation of the amount of rainwater striking the building's facade. ISO 15927 offers the annual average index-mainly to assess the moisture content of absorbent surfaces, and the spell index-more related to the likelihood of water penetration through joints. To calculate these indices, assumptions are made concerning the length of the period of 'no rain', called 'spell definition'. Obviously, the choice of this spell definition will characterise the WDR-amount. In this paper, WDR measurements of a 3-storey building in Vancouver, Canada are used to investigate how this spell definition affects the rain load. Different filter criteria are used to exclude errors due to measurement equipment. By means of the catch ratio as a dimensionless parameter, the results of the analysis for different spell definitions are compared to hourly and 5-min data. It is concluded that longer spell definitions result in lower catch ratios and an underestimation of the WDR load. Hourly data turns out to be a more conservative approach for WDR-assessment of this case study, but is able to represent the spread on the catch ratio most closely to the original 5min-dataset. (C) 2015 The Authors. Published by Elsevier Ltd.

Stripping is one of the most commonly occurring distresses in bituminous pavements. This occurs as a result of destruction of the bond between aggregate particles and bitumen. Impacts of traffic loading, aggregate type, bitumen characteristics and properties of the additives in mixes can modify resistance of mixes against moisture damage. This study is aimed at determining the effects of two different anti-stripping additives, namely hydrated lime and a liquid anti-stripping agent (Iterlene In/400-S) on hot mix asphalt (HMA). Moisture susceptibilities of samples were determined by analyzing digital images taken from coated aggregate particles after performing boiling water test (ASTMD 3625). In addition, Modified Lottman test (AASHTO T283) was performed on mixes containing 0.2%, 0.3% and 0.4% of liquid anti-stripping agent and mixes containing 1%, 1.5% and 2% of hydrated lime. The results indicated that the addition of hydrated lime and liquid anti-stripping agent increased moisture resistance of asphalt mixes to some extent (i.e. 13% and 16% of TSR ratio, respectively). Moreover, it was concluded that mix samples prepared using the liquid anti-stripping additive imparted more correlation and greater resistance to water damage, compared with control mixes and those containing hydrated lime.

The built environment contributes around half of total greenhouse gas emissions and with 87% of residential buildings that we will have by 2050 already built, it is vital to adopt sustainable retrofitting practices. The question is: what are the viable solutions? One answer may be green roof retrofitting. The environmental benefits include reduced operational carbon emissions, reduced urban heat island effect, increased bio-diversity, housing temperature attenuation and reduced stormwater run-off. The economic benefits are the reduced maintenance costs and lower running costs. The social gain is the creation of spaces where people have access to green areas. However, the barriers to retrofitting include the perceptions of structural adequacy, the risk of water damage, high installation and maintenance costs, as well as access and security issues. Many Australian and Brazilian residential buildings have metal sheet roofs, a lightweight material with poor thermal performance. During the summer, temperatures in Sydney and Rio de Janeiro reach 45 degrees Celsius, and in both cities, rainfall patterns are changing, with more intense downpours. Furthermore, many residential buildings are leased, and currently, tenants are restricted by the modifications that they can perform to reduce running costs and carbon emissions. This research reports on an experiment on two small-scale metal roofs in Sydney and Rio de Janeiro to assess the thermal performance of portable small-scale modules. The findings are that considerable variation in temperature was found in both countries, indicating that green roof retrofitting could lower the cooling energy demand considerably.

The life cycle of a road engineering usually contains multiple stages. It starts from design, through the construction, usage and damaged to discarded. Early disease water damage of asphalt pavement has great influence on the service life of road surface. Through analyzing the mechanism of water damage and summarizing the main forms of water damage, this paper puts forward the reasonable distribution of asphalt mixture and the good rigidity relationship between base and surface, which is the key factors to avoid water damage. We analyze and summarize the advantage of drainage asphalt pavement in the prevention and control of water damage of asphalt pavement in order to apply it in the practice of engineering.

Water damage to buildings at research institutions is disruptive and costly. Research Universities have a unique variety of building stock varying from high hazard research laboratories to traditional offices, dorms, multifamily student housing, libraries, residences and rental properties. Each of these represents different challenges. Institutions can benefit from an integrated response to water events that includes prevention and mitigation strategies to reduce the cost and improve the durability of buildings.

Water damage is a frequent major diseases existing tunnel, leakage of water in cold regions is an important factor affecting heaving rock tunnel. In this paper, the existing operators Shenyang Railway Bureau tunnel water leakage survey, exploration and measurement of disease, the degradation mechanism of water seepage analysis, watershed remediation works typical tunnel tests selected. Classification regulation for their different causes water leakage, the use of block, row, cited the comprehensive management of technology, leakage of water moving under conditions of rapid closure of the water chemical grouting materials suitable for cold regions selected Malisan various tunnels. After engineering verification, leakage of water from the tunnel to get a fundamental governance, successfully resolved the existing operational railway tunnel seepage water problems for our existing tunnel seepage water governance provide a reliable basis, has broad application value.

Through a highway asphalt pavement condition survey and analysis of the main causes of disease, through material selection and grading design, the design of the treatment structure, class structure using the drainage layer, exclude the internal structure of the water surface; focused on solving the asphalt pavement water damage issues, effectively extending the life of the highway.

Among the numerous advantages of stone mastic asphalt (SMA) is its ability to provide durable surfacing, as well as its high resistance to rutting due to heavy axle loads. The level of research on the utilization of waste and by-products in the construction of SMA is still low, especially in developing countries. To address this gap, this study evaluated the performance characteristics of SMA incorporating electric arc furnace (EAF) steel slag and copper mine tailings (CMT). Mix 1 consisted of 100% granite; Mix 2 was 80% granite, 20% CMT; Mix 3 consisted of 80% EAF steel slag and 20% CMT; and Mix 4 was 40% EAF steel slag, 40% granite, and 20% CMT. The moisture susceptibility of the mixes was within the allowable limits and the mixture prepared with PG 76-22 is more susceptible to water damage. The resilient modulus of ethylene-vinyl acetate (EVA)–modified 80/100 mixes is also greater than PG 76-22 mixtures at both temperatures of 25°C and 40°C for the unaged and aged samples. The obtained results ...

The new era in the design of modern healthy buildings necessitates multidisciplinary research efforts that link principles of engineering and material sciences with those of building biology, in order to better comprehend and apply underlying interactions among design criteria. As part of this effort, there have been an array of studies in relation to the effects of building characteristics on indoor microbiota and their propensity to cause health issues. Despite the abundance of scientific inquiries, limited studies have been dedicated to concomitantly link these effects to the deterioration of 'structural integrity' in the building materials. This study focuses on the observed biodeteriorative capabilities of indoor fungi upon the ubiquitous gypsum board material as a function of building age and room functionality within a university campus. We observed that the fungal growth significantly affected the physical (weight loss) and mechanical (tensile strength) properties of moisture-exposed gypsum board samples; in some cases, tensile strength and weight decreased by more than 80%. Such intertwined associations between the biodeterioration of building material properties due to viable indoor fungi, and as a function of building characteristics, would suggest a critical need towards multi-criteria design and optimization of next-generation healthy buildings. Next to structural integrity measures, with a better understanding of what factors and environmental conditions trigger fungal growth in built environment materials, we can also optimize the design of indoor living spaces, cleaning strategies, as well as emergency management measures during probable events such as flooding or water damage.

In the evaluation of water-damaged West-East gas pipelines, a variety of impact factors (namely evaluation indicators) such as topography, lithology, rainfall intensity, etc., will be involved. Because of the factors different impacts on the evaluation objectives, the determination of their weight is very important. In order to evaluate the damaged West-East gas pipelines systematically, comprehensively and scientifically, this paper based on the basic principles of analytic hierarchy process (namely AHP), first analyzed the meaning of impact factors weight model according to the damage situation along the West-East gas pipelines, and then evaluated the water-damage using Analytic Hierarchy Process - Expert Weighting method (hereafter referred to as AHP-EW) which reduced the subjectivity and improved the reliability. The practical application verified the rationality and feasibility of AHP-EW method.

We conducted a retrospective, cross-sectional study of flooding, mold exposure, remediation, and respiratory symptom prevalence on a random sample of respondents from Bound Brook, New Jersey, a community that received extensive flood damage from Hurricane Floyd in September 1999. Over 3,000 homes were impacted, some with water damage to the second floor. Many required condemnation. In 2001 to 2002 we conducted a randomized telephone survey of 29 families still living in flood-damaged and repaired homes and 18 families who had not experienced flood damage from Floyd. Flood status was the last question on the interview, leaving the interviewer effectively blinded as to status. Flood damage was a strong predictor of mold growth (p < 0.001), and there was a strong association between flooding and physician-confirmed respiratory symptoms in the aftermath of the flood (28 of 29 cases vs. 10 of 18 referents; p < 0.001). There was also an association between flood status and continued symptom prevalence in the month prior to the interviews (22 of 29 cases vs. 6 of 18 referents; p < 0.01). Most flooded homes required removal and replacement of various building materials, which was usually delayed for days or weeks pending re-occupancy. Many occupants participated in the renovation without adequate personal protection. Persons assisting with cleanup work were more likely to report five or more symptoms (p < 0.002). Smokers with mold damage reported five or more symptoms in the 30 days before the interviews, more frequently than nonsmokers with mold damage. These results are consistent with previous reports of flooding, mold, and illness, but demonstrate that self-remediation of mold (particularly with lack of training and personal protective equipment) and smoking are significant risk factors for mold-related symptoms. Exposure during cleanup of moldy materials was a significant contributor to symptoms, and recommendations should include more reliance on professionals and enhanced personal protective equipment. © 2013 Wiley Periodicals, Inc.

A new product, the surface emissions trap (cTrap), a device developed to stop and bind emissions effectively while having virtually no resistance to water vapor, was installed on a PVC flooring in a school with IAQ complaints. After the installation air concentrations of 2-ethylhexanol decreased rapidly and staff and students reported a considerably improved perceived IAQ. The amounts of 2-ethylhexanol adsorbed on the cTrap cloth 13 months after installation corresponded to only 1.03% of its adsorption capacity. Installing the cTrap may constitute a cost-efficient and effective way of restoring the indoor air quality e.g. following water damage of a building.

PURPOSES: The purpose of this study was to investigate the disintegration mechanism of concrete due to the infiltration of the moisture to the milling overlay pavement and to come up with a method to minimize the disintegration as well as verifying the effectiveness of the edge sealing and Fogseal method. METHODS : This study investigated the distress mechanism due to the infiltrated moisture remaining in the milling overlay pavement through chloride freezing test and verified the effectiveness of the sealing of the milling edge and fog seal methods, which have been devised to minimize the moisture infiltration, through laboratory water permeability test. Additionally, long-term pavement performance was compared for the effectiveness of the proposed method through under loading test, and field water permeability test was carried out to verify the field applicability of the proposed method. RESULTS: The result of the research confirmed that chloride deteriorates the concrete surface through disintegration and lowers its strength and that the laboratory moisture infiltration test verified the effectiveness of the milling edge sealing and fog seal methods in the deterrence of moisture infiltration to the overlay pavement with excellent long-term performance of the pavement treated with the proposed method. Although the field water permeability test revealed some deterrence of moisture infiltration of the milling edge sealing and fog seal methods to a certain extent, the difference was a little. CONCLUSIONS: The milling edge sealing and fog seal methods are limited in their effectiveness for the cases of improvident compaction management or mixture with large void, and it is believed that installation of subsurface drainage is more effective in these cases.

Because of its preventing reflection cracks on the base of the asphalt macadam, improving the high temperature stability and resistance to water damage ability etc, it is getting more and more widely used, but when ATB30 base construction and prone to aggregate segregation and compaction characteristics, combining entity Xu Ping south highway engineering research, puts forward the reasonable paving and rolling technology, effectively avoid the aggregate segregation, improve the degree of compaction, guarantees the construction quality and progress.

In recent years, as the rapid development of highway construction and the increase of road traffic mileage of China, the highway traffic safety smooth has become an essential question of highway projects. In this paper, the second line which was modified by fiber slurry of S211 provincial highway construction engineering as the test prototype. We have calculated the optimum mixture ratio of the slurry mixture which was modified by fiber in the laboratory. In this condition, the shear performance, anti-fatigue performance, water damage resistance and mechanical impact resistance performance of the mixture have improved compared with the mixture without fiber modified. At the same time, the same section road with fiber modified slurry mixture and without fiber modified slurry mixture have been compared and analyzed by finite element method based on the ANSYS. We could draw some basic conclusions: The value of pavement deflection and the tensile stress of fiber modified slurry layered road have reduced compared with the slurry layered road without fiber modified.

Water damage is a vital factor affecting the durability of gap-graded asphalt. There is an urgent need for a pragmatic and reasonable test to evaluate this parameter. Previous research has proposed that tensile strength ratio is a promising test for this application. Therefore, the aim of this paper is to evaluate the effect of moisture damage on gap-graded asphalt mixture incorporating electric arc furnace (EAF) steel slag and copper mine tailings (CMT). Four material mixtures of eight mix designs were investigated. Each mix was conditioned in water for 24-hour and 48-hour before testing. The study adopted retained strength index (RSI), durability index (DI) and tensile strength ratio (TSR) to describe the durability of gap-graded asphalt incorporating EAF steel slag and copper mine tailings. The results reveal that all the mixes fulfill the prescribed criteria. Also, there is a strong correlation between the retained strength index and the durability index with a strong coefficient of determination, R2 of 0.9543. The results of the study further showed that gap-graded asphalt mixture incorporating EAF steel slag and copper mine tailings did not seem to pose any problem.

Water quality assessment programs require the collection of water samples for physical, chemical and bacteriological analysis. Lack of personnel, accessibility of water bodies and time of water sampling after natural disasters and emergencies are some of the challenges of water sampling. A water collection mechanism was developed and mounted on a multirotor unmanned aerial vehicle (UAV) for autonomous water sampling from water bodies. The payload capacity and endurance of the hexacopter were verified using an indoor test station. The hexacopter was equipped with floating foam, and the electronic components were coated against water damage in case of a crash, landing on water due to emergencies or for water sampling. The system was able to collect 130 ml of water for 48 times out of 73 flight missions from a pond. The unsuccessful missions were due to the malfunctions of the triggering mechanism of the water sampler. The UAV-assisted autonomous water sampling is a promising method for collection of water from water bodies. The system would be useful for collection of water samples from large lakes or difficult to access water sources. The details of the developed water sampling mechanism and the results of the experiments are reported in this paper.

Libraries are vulnerable to water damage. Leaks and floods in libraries are common. Human error leads to numerous moisture problems. Many cities have grown near large bodies of water; Canadian examples include Vancouver and Winnipeg. Libraries often lack plans to deal with water damage. Inadequate clean-up can follow a flood. Librarians should learn about their buildings, and find out where any leaks and floods have occurred in the past. A strategic alliance with a moisture control vendor is advisable.

By using GTM method, with equal volume parameters as the criterion, determined the suitable temperature of Evotherm warm-mix rubber-modified asphalt mixture, and applied Marshall method for repeated experiments, holding that GTM method could increase the cooling rate. Then, it firstly proposed a two-stage design method to conduct design of warm-mix rubber-modified asphalt mixture based on the two-parameter system; on the basis of hot-mix asphalt mixture test, it carried out staged design of asphalt content and temperature to ensure the pavement performance in terms of material composition and volume parameters. Finally, the paper conducted performance test of the designed warm-mix mixture and made comparative analysis of the corresponding hot-mix mixture. The results showed that the low and high temperature performances as well as the water damage resistant performance of Evotherm warm-mix rubber-modified asphalt mixture were superior than that of hot-mix mixture, and its compression resilience modulus was roughly equal to that of the hot-mix mixture, which would not affect the pavement structure design.

Property-level stormwater drainage systems consist of roof drainage systems and those systems that connect buildings and their surrounding ground surfaces to main sewer networks, on-site rainwater harvesting or other capture systems. The design of these local systems has traditionally been based on simplistic approaches that fail to account for performance and integration. Given the extra demands associated with climate change, these limitations will take on increasing importance due to the potential for site-level flooding or water damage. To address the concerns, new tools are needed to describe and assess performance as well as to enable a more integrated approach. Research is presented on the development of an integrated property-level drainage simulation model and associated whole-life costing model. Application of the model illustrates the importance of accounting for flow interactions in order to assess the hydraulic effectiveness of different adaptation schemes. Similarly, the whole-life cost mode...

Warm mix asphalt may have water damage because of the low construction temperature of warm mix asphalt and the slowrate of water evaporation in aggregate. Simulation test system of dynamic water pressure for asphalt which is independent development by south china university of technology is used for evaluating the water damage resistance of warm mix asphalt under high temperature and comparatively analyzing the influence of aggregate modifying agent on the water damage resistance of warm mix asphalt. Test results show, The loss of the splitting strength is obviously decreased on 15°C and water damage resistance of warm mix asphalt is significantly improved after asphalt specimens of warm mix SMA-13 with aggregate modifying agent through 3h simulation test of dynamic water pressure on 60°C；Research results have an important meaning on reducing the early disease of warm mix asphalt in high temperature and rainy

Asphalt pavement of water damage is a major form of our country highway asphalt pavement damage, the paper analyzes pavement structure internal water source, water damage of asphalt pavement of the influence factors, through the determination of the three indexes and asphalt of asphalt mixture splitting tensile strength, water erosion proof of asphalt mixture and its influence, and put forward the corresponding prevention and control measures to improve the pavement performance and extend the service life of road surface has important practical value.

In this study, plant-mix hot reclaiming asphalt mixture can be used to surface and sub surface taking DAC-13I and DAC-20I asphalt mixture with five different RAP contents as 0%, 10%, 20%, 30%, 40%. The fatigue, rutting, water damage and cracking tests in laboratory have been taken to evaluate the road performance, and flexure, rutting, asphalt content tests have been taken on the trial sections to evaluate the practice road performance. The result of tests shows that plant-mix hot reclaiming asphalt mixture should be good service performance as new asphalt mixture when the RAP content is appropriate.

Moisture can be defined as the early loss of strength and durability caused by moisture penetrating through the asphalt-aggregate mixture. This failure can be adhesive occurring at the asphalt-aggregate interface or cohesive occurring within the matrix (asphalt binder plus mineral filler). Therefore, the knowledge of chemical thermodynamics theory will help a great deal in understanding the adhesive properties of the asphalt mixture within the water. Water damage model of asphalt mixture are presented based on surface and interface theory. Two types of aggreates, a limestone and sandstone, two asphalt binder of base asphalt and SBS modified asphalt are used to produce four different mixutres of HMA in the paper. The four mixtures are subsequently tested using the method and ranked. According analysis of results, the methods based on chemical thermodynamics theory offers viable alternative to the assessment of water susceptibility of HMA. This method is simple, quicker and equipment utilized can easily and cheaply be assembled.

A centrifugal earth structure deformation test system has been developed to study the mechanism and pattern of subgrade damage as caused by water wetting to the widened roads in collapsible loess areas. It incorporates an upgraded electric sensor logging system and a centrifugal field image pickup system and provides a centrifuge model test platform for both the new road and the original road that are subject to water wetting and infiltration. A centrifuge test model on which actual stress distribution can be simulated was set up to study the forms of water damage to the widened subgrade. In the same time, special research was conducted with regard to the working mechanism of geogrid in the splice between the new road and the old, as well as the effect of dynamic compaction on loess foundation. It indicates that high water content in the toe of slope of a widened road could significantly influence the stability of subgrade. Local instability in loess foundation, as caused by the presence of high level of underground water especially after a heavy rain, could be a great threat to the integrity and safety of the subgrade on top of it. In this case the loess foundation, which is locally wetted and softened by water, would undergo a reduction in shearing strength and gradually lose its stability under the load of subgrade, that eventually results in the sliding or separation between the new subgrade and the old. The reinforced materials used in the splice can enhance soil hardening and help establish soil arching effect under which the settlement of subgrade is well controlled.

Analyze and study the deformation and damage of asphalt pavement which is under the combined action of seepage and vehicle payload by the finite element analysis software ANSYS. Through the study and analysis of the deformation and damage of the asphalt pavement in the three cases of seepage, vehicle payload, and the combined action of seepage and vehicle payload, the study shows: the damage of the asphalt pavement emerges mainly under the vehicle payload, but after the seepage, the damage under the combined action of seepage and vehicle payload will be more serious.

Building stones are porous media and they can deteriorate through moisture ingress and secondary damage such as crystallization of soluble salts. Not only is this due to the increasing number of flood events in the past years but also structural damages of houses from activity such as leakage or rising moisture (groundwater) are the main causes. The potential benefit of several nondestructive testing methods to assess water damage in building stone has been studied in a field-scale experiment. Three testing walls made of fired clay brick, sandstone, and spongilite were flooded and their drying behavior monitored using infrared thermography, complex resistivity, ground penetrating radar, and ultrasonics. The results were compared to the average moisture content determined by gravimetric weighing of the specimens. Qualitatively, the results of the different nondestructive testing methods matched well. But in terms of quantitative data, some scatter was observed and the results should be viewed with care. Co...

This paper resulted from a Structural Engineering Institute of the American Society of Civil Engineers Special Project entitled "The Next Step for ASCE 16: Performance-Based Design of Wood Structures." In 2005 Hurricane Katrina demonstrated how damaging flood waters can be to residential structures. While life safety of the occupants is the most critical issue for residential buildings the financial (property) loss due to water damage is often extensive and can result in personal financial ruin. This paper presents the methodology including several illustrative examples for the design of wood-frame residential structures for flood. The methodology is based on probabilistic flood hazard as defined by the U.S. Federal Emergency Management Agency and provides a probabilistic measure of annualized loss or loss over the anticipated/expected lifetime of the building. The primary purpose of this information is to aid in the decision making process during planning, construction, or the retrofit process. The approach is based on known properties of wood and housing products, and when not available, reasonable interpretations/assumptions were used based on expert opinions of those in the wood and/or housing industry.

Moisture damage is a primary mode of distress occurring in hot mix asphalt (HMA) pavements. Usually, the acid aggregate like gneiss must use some anti-stripping additive to resist water damage. Hydrated lime is best known as an anti-stripping additive since 1910. The purpose of this paper is to look at some aspects of the effects of aggregate chemical properties and hydrated lime on the dynamic mechanics and stripping behavior of hot mix asphalt. Two types of aggregates evaluated in this study were limestone and gneiss. The effects of the aggregates type were evaluated on four different aggregate gradations which were composed with the two aggregates in different proportion. And the hydrated lime has been used for HMA pavements to mitigate moisture-related damage in gneiss asphalt mixture. Laboratory tests for different asphalt mixture include Marshall Test, Frozen-thaw Cycle Test, Dynamic Modulus Test (DMT) and Indirect Tensile Fatigue Test (ITFT). Testing data and analyses demonstrated that different aggregate gradations have different mechanical properties. Hydrate lime has greatly contributed to moisture damage resistance in acid aggregate gneiss and enhanced the dynamic modulus. The modified with hydrated lime mixture composed with coarse gneiss aggregate and fine limestone aggregate also has better performance of the mixture against rutting, fatigue and thermal cracking. It can be concluded from ITFT tests that the fatigue life (load cycle times) of additive hydrated lime asphalt concrete is more than neat ones. At last, we can conclude that the selection and design that modified with hydrated lime and fine limestone aggregate replace acid aggregate could create multiple benefits in asphalt mixtures.

The aim of this paper is to suggest a unified test method that allows investigation into the different effects and contribution of water damage and temperature cycles on fatigue performance of asphalt mixtures by means of a CoAxial Shear Test (CAST). A continuum damage approach, based on the elasticity theory, is chosen to determine the damage level of each tested specimen. The proposed mathematical model allows the simulation of the modulus evolution in the fatigue test and takes into account the temperature cycles. In this way, a unique scalar damage factor determines the damage process severity in each specimen and allows a rational comparison between each different condition.

Purpose - Water damage is a severe problem in modern construction, causing economic loss and health implications. By using the patented Air Gap Method inside building constructions, harmful water i ...

PurposeWater damage is a severe problem in modern construction, causing economic loss and health implications. The patented Air Gap Method, which is a slight modification of the common infill wall construction, provides means to build houses in a more robust way, minimizing the negative effects of water damage. This full‐scale study of the method aims to show how walls and floors may be built to create ventilation within the construction, with air gaps equipped with heating cables. The general hypothesis is that the patented Air Gap Method drains and evaporates dampness after water damage. The purpose of this study is to show how the method is built and how the method deals with water damage, such as a flooding, and with mould growth.Design/methodology/approachThe Air Gap Method is based on a common timber‐framed construction and is completed by the provision of inlets, air gaps, slits, and outlets. The power for the convective airflow is given by an electrical heating cable. The study was carried out as a full‐scale experiment using a 24 m2 large apartment build by this method. This apartment was flooded with 120 litres of domestic wastewater and the drying period was compared when heating cables were switched on or not. Mould growth was also investigated.FindingsThe method dries out a flooded floor in nine days when two heating cables were switched on, in 13 days with one heating cable and 21 days when the heating cables were off. The method prevents all mould growth provided that the indoor RH is lower than 65 per cent.Practical implicationsThe method provides means to build houses in a more robust way, minimizing the negative effects of water damage.Originality/valueThe issue of ventilated construction is rarely investigated in scientific research.

Hot and rainy weather condition in southern areas of China demands materials that can deliver durable road performance. To accommodate specific requirements and current traffic conditions, studies on high performance asphalt mixture modifier in asphalt mixture were conducted in both laboratories and highway construction. The authors discovered that over 7000 times/mm dynamic stability, superior water damage resistance, and low temperature performance can be achieved when the dosage of the modifier was equal to or greater than 0.3%wt. In addition, higher dynamic modulus and anti-fatigue performance was achieved as well in the presence of the modifier. Application of the asphalt mixture modifier on several highway constructions in southern China such as G40, G50, and the 2nd city ring in Chengdu demonstrated less track rutting and deflection than traditional methods. Economic benefits are also discussed in this paper.

Along with the rapid development of highways in China, the performance of road pavement is being increasingly challenged. Highways in seasonally frozen areas, widely distributed in northern China, tend to infect diseases as heaving/ frost boiling attributed to recurrent freezing and defrosting of water in the soil as well as fatigue load exerted by overloading vehicles. This paper focuses on the performance evaluation of rock asphalt, modified asphalt in seasonally frozen areas. Buton Rock Asphalt (BRA) is chosen as a representative. Laboratory and field tests are conducted and the result manifests that BRA can: (1) upgrade the aggregate-binder cohesion and thus strengthen the high temperature stability significantly; (2) promote the low temperature cracking resistance to some extent; and (3) enhance the resistance to water damage. Additionally, a simplified analysis is made to verify the economic and environmental value of BRA modified asphalt.

Maintenance and reconstruction of road pavements involve the production of huge amount of discarded material, such as reclaimed asphalt (RA), every year. As a consequence, issues related to RA stockpiles and disposals are dramatically increasing. At the same time, the growing importance of environmental and economic matters has led researchers and engineers to promote reusing milled materials rather than using valuable and nonrenewable natural resources (bitumen and aggregates). Road pavement maintenance and construction usually involve the use of porous asphalt (PA) mixtures, in particular in the case of motorways and highways. In fact, PA mixtures are widely employed as pavement surface layer thanks to their ability in reducing traffic noise and enhancing safety in wet conditions. In this sense, the reuse of RA into PA should be strongly encouraged. Unfortunately, technical specifications adopted in many countries do not allow any recycled materials in porous asphalt surface layers yet. Thus, re...

Studies of hurricane damage to residential buildings confirm that the risk of wind and/or water damage related losses can be mitigated via retrofit solutions. However, adoption of appropriate retrofits by homeowners has been limited despite its obvious benefits. For several reasons, including high cost of retrofitting, the practical difficulty of implementing upgrades, and other homeowner priorities, the level of structural retrofits remain low. This paper proposes a performance-based design approach to retrofitting, targeted for residential homeowners (and their construction team) to advise on incremental retrofits that ultimately result in desired performance targets for windresistant houses. To specifically engage the homeowner, a user-friendly smartphone application is developed that evaluates the wind resistance and vulnerability of existing homes. The app provides each homeowner an individualized vulnerability assessment, while engaging and educating them on the effects of structural systems and building characteristics on damage and on the options for retrofits and costs associated with the work. The vulnerability assessment is determined using a database of fragility curves, developed originally for the FEMA’s HAZUS-MH program, and adapted for this use. The analysis yields the top three recommended retrofits for each house as-is, and its expected hurricane-induced economic losses compared against the predicted loss if all the retrofits were conducted. Beta trials of the mobile app will be conducted in at-risk coastal communities in Florida, USA. The authors suggest that direct engagement of homeowners in identifying wind mitigation techniques and solutions may yield more positive outcomes than traditional communication approach and it may eventually increase the number of building retrofits.

Las desventajas de los bloques de tierra comprimida son sus baj as propiedades mecánicas y resistencia al daño al agua. Por lo tanto, su uso es vulnerable al deterioro y requiere cuidado y mantenimien to, dependiendo del grado de estabilización y compactación del suelo arcilloso. Residuos de minería del yeso y cal se utilizaron com o estabilizantes para mejorar las propiedades de estos material es de construcción. Resistencia a compresión y flexión, ablandamiento en agua, retracción por secado y peso unitario se determinaron . La resistencia aumento con la adición de residuo de minería. La re sistencia al ablandamiento en agua fue mayor con 25% de residuo de minería. La contracción por secado disminuyo con el aumento del contenido de residuo de minería. El peso unitario seco no esta ba en los estándares recomendados. Los resultados mostraron que los resid uos de minería del yeso pueden utilizarse como materiales alter nativos en la estabilización de bloques de tierra comprimida.

PurposeThe objective is to address the major issues and suggest solutions to solve the water seepage and health related problems in residential buildings.Design/methodology/approachThe methodology relies on a literature review on water damage in residential buildings with references to the vertical spread of SARS in a housing estate in Hong Kong. Working procedures for handling seepage complaints by Hong Kong government departments and their performance are examined.FindingsThe study found that individual departments have difficulties in identifying: the cause and source of seepage, and resolutions to the problem given the limited powers and legal constraints that exist. A holistic approach by individual departments is needed to address the issue. The proposed formation of Owners' Corporations, third party insurance and repair and maintenance sinking fund for old buildings would help solve the building defect and health related problems.Practical implicationsThe suggestions in the study would help reduce and partly prevent the environmental nuisance and, more importantly, health risk. Residents are better prepared in the future for a possible return of SARS or other infectious disease.Originality/valueResearch on water damage is very scarce in Hong Kong. And perhaps this is the first of its kind. The study identifies the broader issue of maintaining and managing a high‐rise residential building. The building management and health related problems identified in the study should be noted in any policy addressing housing and health issues.

Protecting small retail shops packed with combustible goods by sprinkler system might not be too satisfactory. Any delay in system activation will lead to a flashover fire. Also, there might be serious water damage which is not good for shops selling expensive items. Alternative fire protection systems should be searched for. Water mist might be effective for suppressing postflashover fires if the system is designed properly. Whether water mist fire suppression systems can be used in the small shops is discussed in this paper. Key factors affecting the system performance will be discussed. Potential application strategies are outlined. An example was used to illustrate the design of the system.

Excess water content within the building material could greatly alter the interaction of the microwave with the material. In this study aerated concrete (AEROC) block walls (60x60cm) were investigated for their microwave (2.4 GHz) properties under wetting conditions. The spray wetting of the wall was conducted to simulate the environmental processes such as raining or water damage. 50ml/m² water dosage was applied on the surface of the concrete 21 times in 1 min intervals. The results show a noticeable decrease in microwave penetration power through the material after the sample gets enriched with water. As the water content on the surface of the material rises, so does the transmission loss. During the different water content of the aerated concrete, the reflection loss varied from -15.04 dB (dry wall) to -5.03 dB (wet wall’s surface). The transmission loss continues to rise during the entire length of the experiment, from -4.5 dB as a dry sample to -8.3 dB after 441 ml (1035 ml/m² during 23 min) of sprayed water. The variation of reflected microwave power was approximately ten times, which is quite a significant indicator of alteration of microwave propagation. The results demonstrate wetting process as an considerable factor in assessing microwave propagation in near the sources, such as mobile phone base station antennas, industrial microwave heaters and ovens etc.

This paper reports on a wide-ranging study conducted on the interim technical assessments (ITAs) drawn up for lawsuits over defective constructions in Tuscany, Italy, from 2000 to 2011. It provides a set of statistically significant data to highlight the impact of construction defects in buildings and evaluate their origins and the responsibilities of the technical personnel involved. The data have been classified according to various categories based on the type of damage encountered. Analysis of the most common types (in particular, water damage) and comparisons with the data from a similar survey carried out in 1990–1999 provide indications as to the critical aspects deserving of special attention, including building design and inspections during construction. Such analysis can provide useful information for assessing whether the quality of construction has kept pace with new knowledge and advances in technology.

The large-scale water storage pipes taken as the subject of this study have basins of at least 4,000 ha and are connected to numerous main sewers/pump stations. Therefore, operation of the storage pipes to make maximum use of the storage effect is a complex challenge. This research aimed to conduct a study for efficient operation of each pump station and effective use of main lines in regard to various rainfalls in a large-scale storage pipe basin. We confirmed that it would be possible to shut down pump stations during construction, if the pump station needs to be reconstructed, by connecting multiple pump stations with a network of the large-storage pipe across a drainage area. The simulation results also verified that this design method is effective for the maximum recorded rainfall, which exceeds the target design rainfall. This is considered to be because actual rain does not uniformly fall over a basin (rainfall tends to be unevenly distributed), and so a network effect between pump stations is displayed in which low-operating pump stations are compensated for by other pump stations. The methods for effective use resulting from this research are considered to be widely applicable, and we intend to confirm these results in other basins in the future.

Low-slope roofs are widely used but they are often vulnerable to water damage. As removal of water is difficult and expensive, low-slope roofs often have short service life and poor cost-performance ratio. To improve the durability of low-slope roofs, a dryable-on-demand roofing system has been proposed. The design, which includes a mechanism for moisture detection, was evaluated by means of numerical modeling and laboratory measurements. Compared to traditional low-slope roofs, the suggested design offers several advantages including better cost-effectiveness, lower replacement costs, and lower use of resources. The paper shows that building envelope components that are prepared for repair and maintenance may be cost-effective.