Assessment and forecast of the culvert’s performance within a road infrastructure management system. Literature review

During the 21st century, within road infrastructure management there is a strong enforcement on preserving assets and prevent roadway collapses. As a result, public agencies have to implement periodic inspections and asset condition assessments. As pavements and bridges also culverts management play a special role in roadway safety, because they prevent roadbed erosion. The scope of this investigation is the assessment and forecast of culverts performance regarding rating condition and network reliability forecast. In addition, it intends to analyze hazards influence in the culvert serviceability, modelling the hazards actions on the infrastructure. In this paper, is performed the literature review of studies done during the past decade comparing advantages and limitations. Five main subjects are identified in the development of a culvert management system, since the inventory and inspection framework, to forecasting models and risk assessment. Moreover, it will determine the correlation between subjects and will find gaps for improvement.(undefined

Concreto autoadensável em regiões costeiras de clima quente

O concreto autoadensável (CAA no Brasil e SCC internacionalmente) já vem sendo aplicado há aproximadamente 20 anos e vem se tornando alternativa tecnicamente viável para aplicação em lugar do concreto convencional vibrado (CC). Atualmente, constata-se que os estudos sobre o SCC avançaram muito e já possível responder a quase todas as indagações acerca do comportamento do SCC frente ao CC, vantagens e possíveis desvantagens nos aspectos técnicos de aplicacação e utilização

Valorisation of wood fly ash on concrete

Wood fly ash (WFA) is a waste material produced in power plants as result of forest residues combustion to produce power and heat. In countries like Portugal, this waste is disposed of in landfills. Since this material shows pozzolanic characteristics, several studies have been done to evaluate its use as a construction material. This work shows an overview of some published results about the effect of the utilisation of WFA, as a supplementary cementitious material, on the durability and quality of concrete. The results showed that the increase on the wood fly ash content leads to a negative effect on the concrete properties when compared with a conventional concrete. However, the results showed that the behaviour of wood fly ash concrete is very similar to the coal fly ash concrete, which is the most pozzolanic material used in the world. In terms of durability, it was verified that WFA improved the most of the durability characteristics with the exception of carbonation resistance. However, more experimental analysis needs to be developed in terms of wood fly ash concrete durability. Results suggested that using wood fly ash to replace cement is a valuable sustainable option for concrete production. This manuscript discusses the key factors and attempts to provide new information about the application of the wood fly ash on concrete.The authors wish to thank the Portuguese Foundation for Science and Technology (FCT) and the Eco-Construction and Rehabilitation Doctoral Programme for supporting the PhD scholarship (reference PD/ BD/52661/2014). This work was also financed by FEDER funds through the Competitivity Factors Operational Programme – COMPETE and by national funds through FCT – Foundation for Science and Technology within the scope of the project POCI-01 – 0145-FEDER – 007633 and through the Regional Operational Programme CENTRO2020 within the scope of the project CENTRO-01 – 0145- FEDER – 000006

Análise de desenvolvimentos no domínio dos materiais de construção auto-reparadores

A degradação de infraestruturas é atualmente um tema de grande importância quer pelos custos associados na sua futura reparação e reabilitação, quer também pelas gravosas consequências sociais e económicas devido à sua utilização condicionada aquando da execução das obras de reparação e reabilitação. As investigações sobre materiais que permitam minimizar estes problemas levaram ao estudo mais aprofundado de materiais com capacidade de auto-reparação, possibilitando a obtenção de estruturas mais sustentáveis, duráveis e com custos mais baixos. Neste artigo serão aprofundadas quatro vertentes para a auto-reparação do betão, nomeadamente, a auto-reparação com recurso à utilização de cápsulas ou fibras ocas contendo agentes químicos, por hidratação posterior, betões com ductilidade ultraelevada e auto-reparação por recurso a bactérias. Também se terá em atenção o estudo destes materiais que favoreçam a durabilidade do betão e minimizem os efeitos prejudiciais para o ambiente durante a sua produção

Treatment of Hepatitis C Virus Infection in Kidney Transplant Recipients: Case Report

Chronic hepatitis C virus (HCV) infection exists in a large proportion of patients undergoing renal transplantation. Nowadays it is not considered to be an absolute contraindication to transplantation; however, it is associated with an increased risk for the patient and accounts for a shorter half-life of the renal allograft. We present three transplant recipients who displayed serious hepatic dysfunction after renal transplantation due to an HCV infection. In two of these cases, the liver biopsies established the diagnosis of FCH. In the third case, the liver biopsy was compatible with the early stages of FCH. All patients were started on peg-interferon alfa 2-b and ribavirin with subsequent normalization of hepatic function and early complete viral responses

Study of a new interlocking stabilised compressed earth masonry block

Earth has been a traditional construction material to build houses in Africa. One of the most common earthen masonry techniques is the use of sun dried or kiln fired adobe bricks with mud mortar. Although this technique is cheap and allows the self construction, the bricks vary largely in shape, strength and durability. This has lead historically to weak houses which suffer considerable damage during floods and seismic events. Furthermore, the use of firewood kilns to burn bricks has caused extensive deforestation in several countries of Africa. A solution which has been proposed in the second half of the last century is the use of stabilised compressed earth blocks (CEBs). These blocks are manufactured by compacting stabilised earth in a manual or hydraulic press. The resulting blocks present higher values of strength and durability, as well as uniform shapes. Since earth is available almost in every location of the world, the CEBs can be produced in-situ. The fact that this blocks are unburned and that the transport can be omitted makes them a cheap material with very low embodied energy. Their use is a cost effective opportunity for locals to have better houses while reducing deforestation. In this context one developed an ongoing study for the manufacture of CEBs according to different materials available in Malawi. It is envisaged that the constructive solution with theproposed CEBs will enable improvements in durability, in thermal and acoustic comfort and in seismic behaviour of buildings in Malawi, where earth is an abundant material and labour isunskilled. This paper presents some results of the experimental campaign which has been carried out. Forthis purpose, soils from Malawi were characterized and tested without stabilization, as well aswith cement and/or lime addition

ISS na Constituição e na lei

Divulgação dos SUMÁRIOS das obras recentemente incorporadas ao acervo da Biblioteca Ministro Oscar Saraiva do STJ. Em respeito à Lei de Direitos Autorais, não disponibilizamos a obra na íntegra.Localização na estante: 336.241(81) B273

Quality and durability properties and life-cycle assessment of high volume biomass fly ash mortar

The effect of using biomass fly ash (BFA) on the quality, durability and sustainability of mortars was studied. Using high amounts of BFA does not lead to a production of mortars with better performance than a plain cement mortar. However, when BFA is used in small amounts mixed with coal fly ash, mortars with similar compressive strength, to that of a cement mortar, but with less carbonation and with better environmental performance are obtained. Using BFA in the concrete industry can lead to a minimisationof issues related to the high volume fly ash concrete.The authors wish to thank the Portuguese Foundation for Science and Technology (FCT) and the Eco-Construction and Rehabilitation Doctoral Program for supporting the PhD scholarship (reference PD/BD/52661/2014). This work was also financed by FEDER funds through the Competitivity Factors Operational Programme – COMPETE and by national funds through FCT – Foundation for Science and Technology within the scope of the project POCI-01- 0145-FEDER- 007633 and through the Regional Operational Programme CENTRO2020 within the scope of the project CENTRO-01- 0145-FEDER- 000006.info:eu-repo/semantics/publishedVersio