28 research outputs found

    Concretos com Agregados Residuais de Construção e Demolição e Pozolanas

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    Com o crescente aumento do consumo dos recursos naturais em nível mundial, geram-se grandes preocupações em relação ao meio ambiente, tornando a sustentabilidade um assunto em destaque quanto à qualidade de vida e a sobrevivência dos seres vivos. A presente pesquisa visa analisar misturas de concreto com agregado residual de construção e demolição (RCD) através dos ensaios de resistência à compressão axial. Os concretos estudados foram moldados com substituição de dois teores de agregado residual, ou seja, substituições de 15 e 30% do agregado graúdo por RCD, o cimento também foi substituído parcialmente por dois tipos de pozolanas em misturas binárias e ternárias, em que se realizaram substituições de 25% de cimento por cinza de casca de arroz (CCA) e 25% de cinza volante CV) para as misturas binárias, já para as ternárias os teores de substituições foram de (15+10) % (CCA+CV). Para os ensaios de resistência á compressão axial foram moldados corpos de prova cilíndricos de dimensão 10x20cm e curados em câmara úmida por um período de 28 dias. Através dos resultados pôde-se perceber que em relação ao traço referência (sem substituições), os concretos com pozolanas, tanto em misturas binárias como ternárias obtiveram resistência à compressão axial bem próximos da referência, já os traços moldados com substituições somente de agregados resultaram em resistência à compressão axial bastante inferiores. No entanto, concluiu-se que em relação à resistência à compressão axial é viável a utilização de RCD em concretos, porém quando da utilização de pozolanas na mistura.With the increasing consumption of natural resources worldwide, there are great concerns about the environment, making sustainability a prominent issue regarding the quality of life and survival of living beings. This research aims to analyze concrete mixtures with construction and demolition residual aggregate (RCD) through axial compressive strength tests. The concretes studied were molded with substitution of two contents of residual aggregate, ie substitutions of 15 and 30% of the coarse aggregate by RCD, the cement was also partially replaced by two pozzolans in binary and ternary mixtures, in which they were made. substitutions of 25% of cement by rice husk ash (CCA) and 25% of fly ash CV) for binary mixtures, while for ternary substitutions levels were (15 + 10)% (CCA + CV). For the tests of resistance to axial compression were molded cylindrical specimens of dimension 10x20cm and cured in a humid chamber for a period of 28 days. Through the results it could be seen that in relation to the reference trait (without substitutions), the pozzolan concretes, in both binary and ternary mixtures, obtained resistance to axial compression very close to the reference, whereas the molded traces with substitutions of aggregates only resulted in much lower axial compressive strength. However, it was concluded that in relation to the axial compressive strength the use of RCD in concrete is feasible, but when using pozzolans in the mixture

    Italian guidelines for the diagnosis and treatment of Paget's disease of bone

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    Paget's disease of bone is a chronic focal abnormality of bone turnover that remains totally asymptomatic over a very long period of time but that eventually ensue in bone pain and skeletal deformities. Although, in the last decade new insights have been obtained on its etiology, this remains largely obscure. Effective medical treatment (based on the use of bisphosphonates) has become available and the diagnostic procedures are now well defined. However, there remains considerable controversy regarding the hierarchy of diagnostic procedures and the medical treatment threshold. In the last few years different institution have published national guidelines, reflecting local national health systems and the available medical treatment. In this review, a working group derived from members of the SIOMMMS has examined the information available regarding the diagnosis and treatment of Paget's disease in order to develop guidelines to assist in the management of this condition. The first draft was then extensively reviewed by experts derived from the most representative scientific societies of rheumatology, internal medicine, and orthopaedic surgery. The document provides the most updated recommendations based primarily on the "evidence-based- medicine" but also on the Italian regulation for the diagnostic procedures and on the available medical treatments

    Guidelines for the diagnosis, prevention and treatment of osteoporosis

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    The guidelines for the osteoporosis management were first drafted by a working group and then critically evaluated by the board of SIOMMMS. The most relevant points are: Definition: Osteoporosis is defined as a quantitative and qualitative deterioration of bone tissue leading to increased risk of fracture. Postmenopausal and senile osteoporosis are defined as primitive. Diagnosis: The cornerstone for the diagnosis of osteoporosis is the measurement of bone mineral density (BMD) by DXA (dual-energy X-ray absortiometry) at the femoral neck with T-score values -2.5 is usually not justified. Pharmacological intervention: The use of drugs registered for the treatment of osteoporosis are recommended when the benefits overcome the risk. This is the case only when the risk of fracture is rather high. FRAX™ is recognized as a useful tool for easily estimate the long-term fracture risk. SIOMMMS with these guidelines is committed to validate and further develop this diagnostic tool

    Continuing outcomes relevant to Evista:Breast cancer incidence in postmenopausal osteoporotic women in a randomized trial of Raloxifene

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    Zoledronate in the prevention of Paget's (ZiPP) : protocol for a randomised trial of genetic testing and targeted zoledronic acid therapy to prevent SQSTM1-mediated Paget's disease of bone.

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    Introduction Paget’s disease of bone (PDB) is characterised by increased and disorganised bone remodelling affecting one or more skeletal sites. Complications include bone pain, deformity, deafness and pathological fractures. Mutations in sequestosome-1 (SQSTM1) are strongly associated with the development of PDB. Bisphosphonate therapy can improve bone pain in PDB, but there is no evidence that treatment alters the natural history of PDB or prevents complications. The Zoledronate in the Prevention of Paget’s disease trial (ZiPP) will determine if prophylactic therapy with the bisphosphonate zoledronic acid (ZA) can delay or prevent the development of PDB in people who carry SQSTM1 mutations. Methods and analysis People with a family history of PDB aged >30 years who test positive for SQSTM1 mutations are eligible to take part. At the baseline visit, participants will be screened for the presence of bone lesions by radionuclide bone scan. Biochemical markers of bone turnover will be measured and questionnaires completed to assess pain, health-related quality of life (HRQoL), anxiety and depression. Participants will be randomised to receive a single intravenous infusion of 5 mg ZA or placebo and followed up annually for between 4 and 8 years at which point baseline assessments will be repeated. The primary endpoint will be new bone lesions assessed by radionuclide bone scan. Secondary endpoints will include changes in biochemical markers of bone turnover, pain, HRQoL, anxiety, depression and PDB-related skeletal events

    Comprehensive Strength of Concrete Containing Silica Fume

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