Despite improved liner design, there are still reported incidences of landfill leachate, rich in heavy metals, percolating through to groundwater and threatening ecosystems. This thesis introduces the concept of segregating municipal solid wastes (MSW) according to their major heavy metals and their metal's adsorption compatibility. Each segregated portion can be disposed in a different landfill compartment to minimize leaching of these heavy metals with the greatest bioactive impact. The validity of the concept was evaluated by batch and column retention mobility studies using copper (Cu) alone or with either lead (Pb) or cadmium (Cd) in solutions bearing various pHs. This was supported by selective sequential extraction (SSE) to determine the affinity to specific liner fractions. The following summarizes the procedure used. / Beforehand, a soil column test using sand with 5 and 10% bentonite was conducted to develop an equation predicting liner permeability, k , under simulated field conditions. The column permeability test revealed that a liner with 5% bentonite resulted in a k value which respected the North American criteria of 10-5 m/s. / In the batch experiments, solutions with Cu alone or with Cd or Pb, adjusted to pH of 3.7, 5.5 or 7.5, were applied to sand liners with 0%, 5% or 10% bentonite, having CEC's of 2.0, 6.4, and 10.8 (cmol(+) kg-1 ), respectively. Bentonite, pH and Pb significantly affected Cu adsorption. Cu was adsorbed by the liners at pH <6.5 whereas Cu precipitated at pH >6.5. Cu retention was higher in the presence of Cd than in that of Pb, at all combinations of CEC and pH. Competition between metals was greater in liners with lower CEC and therefore fewer adsorption sites. Limiting Pb in a landfill compartment can improve Cu adsorption at pH's below the precipitating threshold. / In the SSE procedure, the liner samples were centrifuged, decanted from their solutions and each adsorption fraction analyzed for Cu content. Results indicated that the carbonate fraction adsorbed more Cu, and that Pb significantly increased the mobility of Cu due to competition for exchangeable sites. / In the final soil column test using a sand liner with 5% bentonite, the leachate had an initial pH of 3.7. The leaching test confirmed the compatibility of Cu with Cd. The leaching of Cu was greater in the presence of Pb. Total metals in leachate was greater for the Cu-Cd solutions than for the Cu-Pb, because of Cd's relatively high mobility. The sequential extraction results showed again that the carbonate fraction dominated metal adsorption. Total heavy metal leaching followed the order of Cu/Cd > Cu/Pb > Cu alone. / Thus, disposing MSW in landfill compartments based on their heavy metal compatibility can minimize migration of heavy metals.

Frictional stability and wear resistance are key performance requirements for heavy truck brake linings. Lining-counterface friction affects the rate of vehicle deceleration, but wear also affects stopping characteristics because uneven or high wear can alter the contact geometry of the lining, change the pattern of frictional heat generation, and degrade the response of the braking system. Inertia dynamometer wear tests are commonly conducted in the linings industry, but are expensive and time consuming. It is therefore of interest to seek more convenient, lower-cost test methods that still enable wear rates of various linings to be effectively differentiated. The purposes of the current study were to determine whether the wear of brake lining materials can be measured in shorter-term laboratory tests, and if so, to determine to what extent the relative ranking of several lining materials' wear resistance depends on the method of testing. To investigate these issues, three commercial truck brake lining materials were worn against gray cast iron using three different laboratory-scale wear testing machines. Assessments of wear by gravimetric methods and dimensional changes using the same test apparatus were compared. The three linings ranked in similar order in all three kinds of wear tests, but the relative differences between the wear of one lining and another differed among the test methods. Results are discussed in terms of what test conditions are required to simulate brake lining wear in trucks, and how in situ lining material aging and transfer film formation can affect the wear of brake lining materials. Differences in the entrapment of third-bodies entering the contact had an important influence on the wear results and an additional set of block-on-ring experiments was conducted to demonstrate that effect. Removing wear debris with a wiper pad altered the relative wear ranking of the three materials.

No / This paper considers both the linear elastic and creep buckling of polymeric pipe linings used for the rehabilitation of gravity pipes, for which external groundwater pressure has been identified as the prime source of loading. Theoretically perfect and imperfect conditions are considered, with the imperfections taken to be in the form of a concentric or eccentric annulus between the rigid host pipe (cylindrical constraint) and polymeric lining. Under these conditions two recently obtained mathematical procedures for the prediction of linearly and non-linearly elastic buckling are compared with the results of complementary laboratory testing. Linear elastic conditions are shown to be well approximated by undertaking short-term (¿30 min) testing under increasing pressure to failure. Controlled imperfections are introduced into the laboratory tests and excellent correlation with the theoretical predictions is obtained. In particular, the dominant geometrical imperfections are shown to be major influences on the obtained buckling pressure. The mathematical models are then adapted to simulate the creep buckling process under long-term constant pressure. The results obtained are again compared with those provided by complementary physical testing, and appropriate conclusions are made.

No / This paper considers both the linear elastic and creep buckling of polymeric pipe linings used for the rehabilitation of gravity pipes, for which external groundwater pressure has been identified as the prime source of loading. Theoretically perfect and imperfect conditions are considered, with the imperfections taken to be in the form of a concentric or eccentric annulus between the rigid host pipe (cylindrical constraint) and polymeric lining. Under these conditions two recently obtained mathematical procedures for the prediction of linearly and non-linearly elastic buckling are compared with the results of complementary laboratory testing. Linear elastic conditions are shown to be well approximated by undertaking short-term (¿30 min) testing under increasing pressure to failure. Controlled imperfections are introduced into the laboratory tests and excellent correlation with the theoretical predictions is obtained. In particular, the dominant geometrical imperfections are shown to be major influences on the obtained buckling pressure. The mathematical models are then adapted to simulate the creep buckling process under long-term constant pressure. The results obtained are again compared with those provided by complementary physical testing, and appropriate conclusions are made.

In many tunnel designs, reinforced concrete tunnel lining design is selected based on construction requirements rather than design loads. A constant cross-section is typically used along a tunnel even if the design loads change from one location to another, especially for tunnels constructed by tunnel boring machines (TBM). Factor of safety against failure is not constant along the length of tunnel and is typically high at shallow depth regions. Factor of safety during a rare event is usually much less than the ones set for service load states. Rare events such as earthquake, train derailment, explosion and long duration fires do not happen daily and generally a minor reparable damage is targeted at the structure during those types of events. The focus of this study is to analytically investigate structural fire safety of reinforced concrete circular tunnel linings in terms of reduction in service load safety and to develop recommendations for preliminary assessment of structural fire endurance of circular tunnel linings. Analytical methods accounting for thermal non-linearity, material degradation, tunnel lining-ground interaction and fire time stages are available to assess the structural fire safety of the concrete tunnel linings. Analytical results are determined to be in good agreement with tunnel key segment hydrocarbon fire test.

The most important issue during a tunnel fire is safety of human life. The tunnel fire structural research and investigations have gained more importance in the last decade but studies show variable results depending on the concrete quality and tunnel design fire. For instance, a certain type of concrete with high moisture content can tend to explode in the first 10-15 minutes of fire with rapid increase of heat release rate. A sudden collapse of the tunnel roof during the fire is unacceptable. Especially in Netherlands, the possible sagging of cut and cover tunnel roof is undesired and prevention systems are applied. The main purpose of this research is to investigate fire response of the positive moment region of cut and cover tunnel roof through an experimental and analytical program without use of any protection. In this context a standard one cell rail road cut and cover tunnel has been designed for loads of backfill, lateral earth pressure and self weight. The typical concrete cover used in Turkish railroad tunnels is 6 centimeters. Four pairs of representative sample tunnel roof segments have been manufactured and only one segment out of each pair are tested under 2 hours extreme design tunnel fire in a furnace. Out of these four types, two types have been internally pre-stressed to simulate the internal loads at the positive moment region of the tunnel roof. Four pairs of sample segments are simply supported during the static load test and static load is applied at the mid-span to measure the difference in the post-fire structural performance. Compressive strength of concrete, tensile strength of reinforcing bars, electron microscope evaluation of concrete, moisture content of concrete are recorded during the test program. A finite element based solution is developed to simulate the results of static load tests. Post-fire structural performances of burnt segments are observed to be not much different than the unburnt segments.

Submitted by ANDREIA SOARES GONÇALVES GLAVINA null (dreia_sg@yahoo.com.br) on 2017-10-26T19:18:28Z No. of bitstreams: 1 GLAVINA, A.S.G._DISSERTAÇÃO UNESP.pdf: 5314361 bytes, checksum: fffce656d9e19dd6aa345f3ba9b2ee9b (MD5) / Approved for entry into archive by LUIZA DE MENEZES ROMANETTO (luizamenezes@reitoria.unesp.br) on 2017-10-30T11:43:55Z (GMT) No. of bitstreams: 1 glavina_asg_me_bot.pdf: 5314361 bytes, checksum: fffce656d9e19dd6aa345f3ba9b2ee9b (MD5) / Made available in DSpace on 2017-10-30T11:43:55Z (GMT). No. of bitstreams: 1 glavina_asg_me_bot.pdf: 5314361 bytes, checksum: fffce656d9e19dd6aa345f3ba9b2ee9b (MD5) Previous issue date: 2017-09-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A relação entre conforto e ambiência é o aproveitamento de recursos passivos que a natureza oferece para dar ao ambiente uma condição favorável e estável em relação ao clima externo e interno. Nessa relação entre o ambiente e a região, o Brasil tem grandes desafios para produção aviária decorrentes de fatores térmicos, é preciso utilizar estratégias para modificar o ambiente interno das instalações destinadas á criação de aves. Desta forma este trabalho teve por objetivo produzir painéis arquitetônicos para forro, utilizando resíduos provenientes da agroindústria (casca de arroz, fibra de coco e polipropileno) e que foram aplicados em um protótipo para os aviários, a fim de aferir os índices de conforto térmico. Para avaliação dos painéis produzidos foram realizados os ensaios de propriedades físico-mecânicas, de acordo com as normas NBR 14810 (2013) e ANSI A208. 1-2006. Foi realizada análise estatística pelo Delineamento Inteiramente Casualizado (DIC) e adotada a análise de variância ANOVA, (p<0,05). Para o ensaio de densidade o tratamento 50PP30CA20FC atingiu a densidade de 608,35kg/m³, classificado como média densidade de acordo com a NBR 14810 (2013); no ensaio de inchamento e absorção de água (2h e 24h) somente o tratamento 60PP30CA10FC atingiu os parâmetros da norma. De acordo com as duas normas, nenhum dos tratamentos atingiu os valores mínimos para ensaio de MOR e MOE. Os quatro tratamentos foram considerados como isolantes térmicos de baixa condutividade (classificação mínima para isolantes é de 0,25 W/mK). Foi avaliado o desempenho dos painéis aplicados nos protótipos como galpões em escala reduzida, para produção de aves. Utilizou-se o programa Orvalho para avaliar os índices de conforto ITU e ITGU, considerando as aves acima de três semanas de vida. Conforme o ITU, com média de 70/71 as aves estariam em situação de conforto nas duas instalações. Para o ITGU a I1 encontra-se em situação de conforto em três horários para as aves com três semanas de vida e a I2 em situação de estresse pelo frio nos quatro horários. A análise pela câmera termogravimétrica registrou temperaturas máximas entre 41 a 43,6°C na instalação sem forro, isso demostrou melhor desempenho térmico na instalação com forro que registrou máximas em 27,1 a 27,8° C, indicando que o forro agiu como um isolante térmico. / The relationship between comfort and ambience is the use of passive resources that nature offers to give the environment favorable and stable external and internal climatic conditions. In this relationship between the environment and the region, Brazil has great challenges for avian production due to thermal factors. It is necessary to use strategies to modify the internal environment of poultry farms. In this way, the objective of this work is to produce architectural panels for lining, using residues from the agroindustry (rice husk, coconut fiber and polypropylene) applied in a prototype to the aviaries, in order to measure the thermal comfort indexes. For the evaluation of the produced panels, the physical-mechanical properties tests were carried out, according to the norms NBR 14810 (2013) and ANSI A208. 1-2006. Statistical analysis was performed using the completely randomized design (CRD) and ANOVA variation analysis was used (p <0.05). For the density test the treatment 50PP30CA20FC reached the density of 608.35 kg / m³, classified as medium density according to NBR 14810 (2013); in the swelling and water absorption test (2h and 24h) only the 60PP30CA10FC treatment reached the parameters of the standard. According to the two standards, none of the treatments reached the minimum values for the MOR and MOE test. The four treatments were considered as low conductivity thermal insulators (minimum classification for insulators is 0.25 W/mK). The performance of the panels applied in the prototypes as small scale sheds for poultry production was evaluated. The Orvalho program was used to evaluate the THI and HGTI comfort indexes, considering birds over three weeks of age. According to the THI, with an average of 70/71 birds would be in comfort in both facilities. For HGTI I1 is in a comfort situation at three times for birds with three weeks of life and the I2 in cold stress situation at four times. The analysis by the thermogravimetric camera recorded maximum temperatures of 41 to 43.6 ° C in the unlined installation, which demonstrated better thermal performance in the lining installation which registered maximums of 27.1 to 27.8 ° C, indicating that the liner acted as a thermal insulation.

Prescriptive fire safety codes regulate the use of combustible room linings to reduce fire risk. These regulations are based on classification systems which designate materials according to their relative hazard when exposed to a standard fire scenario. However, no quantitative data sets on the fire risk of wooden lining materials exist which take into account relevant uncertainties, such as movable fuel loads in compartments. This work is a comparative risk analysis on the influence of wooden linings on the time to flashover in a compartment, considering uncertainties in the fuel load configuration. A risk model is set up for this purpose using B-RISK, a probabilistic fire design and research tool currently under development at BRANZ (Building Research Association of New Zealand) and the University of Canterbury. The risk model calculates fire spread in a compartment between fuel load items and from fuel load items to combustible linings. Multiple iterations are performed considering varying fuel load arrangements and input values sampled from distributions (Monte-Carlo simulation). The functionality and applicability of the risk model is demonstrated, comparing the model with experiments from the literature. The model assumptions are described in detail. Some of the model inputs are defined as distributions in order to account for uncertainty. Parametric studies are conducted in order to analyse the sensitivity of the results to input parameters which cannot be described as distributions. Probabilistic times to flashover are presented and discussed for an ISO 9705 compartment considering varying movable fuel loads and different lining configurations. The fuel load is typical for a hotel room occupancy. Effects of suppression measures are not considered. It is shown that flashover occurs approximately 60 seconds earlier if walls and ceiling are lined with wooden materials than if all linings are non-combustible. This value refers to the 5th percentiles of the time to flashover, i.e. in 5% of the cases flashover has occurred and in 95% of the cases flashover has not (yet) occurred. Referring to 50th percentiles (median values), the difference is approximately 180 seconds. Furthermore it is shown that with wooden wall and ceiling linings in approximately 95% of the iterations flashover occurs, whereas with non-combustible linings 86% of the iterations lead to flashover. After 900 seconds, in 90% of the iterations flashover occurs if walls and ceiling are lined with wooden materials, and in 77% of the iterations if the linings are non-combustible. Using different wooden lining materials (non-fire retardant plywood, fire retardant plywood, and MDF) has no significant effect on the probabilistic times to flashover. Varying the fuel load energy density has an influence only when all linings are non-combustible and when the fuel load energy density is relatively low (100–200 MJ/m2). This work contains recommendations regarding the further development of B-RISK, the research into the fire risk connected with wooden room linings, and suggestions regarding the further development of prescriptive fire safety codes.

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