Dengue occurs throughout the year in Hanoi, Vietnam, despite winter low temperatures <10°C. During July 2010 to March 2012, we surveyed monthly for Aedes larvae and pupae in 120 houses in 8 Hanoi districts. Aedes albopictus preferred discarded containers in summer and pupal density drastically decreased in winter. Aedes aegypti preferred concrete tanks and this preference increased in winter. E...

This study examined the properties of fresh and hardened concretes as influenced by the moisture state of the coarse recycled concrete aggregates (RCA) after surface treatment. Surface treatment was performed by immersing the coarse RCA in a calcium metasilicate (CM) solution. The treated coarse RCA was maintained in three controlled moisture states, namely, air-dried, oven-dried, and saturated...

This paper presents results of compressive strength, capillary water absorption, and density tests conducted on concrete containing recycled aggregate (RCA) which is obtained from structural waste generated by the construction industry in Turkey. In the experiments, 0%, 15%, 30%, 45% and 60% of the normal (natural) coarse aggregate was replaced by the recycled aggregate. Maximum aggregate parti...

This paper presents results of compressive strength, capillary water absorption, and density tests conducted on concrete containing recycled aggregate (RCA) which is obtained from structural waste generated by the construction industry in Turkey. In the experiments, 0%, 15%, 30%, 45% and 60% of the normal (natural) coarse aggregate was replaced by the recycled aggregate. Maximum aggregate parti...

In this study, the elevated temperature flexural strengths of lightweight foamed concrete (LFC) containing fly ash (FA) and polypropylene fiber (PF) was investigated experimentally and statistically. The variables included were the temperature degrees (in a range of 20 to 600°C), LFC densities of 600, 800, 1000, 1200 and 1400 kg/m3 and additive content. Two mixes were made by replacing 15% and ...

PURPOSE The most common material for shielding is concrete, which can be made using various materials of different densities as aggregates. New techniques in radiotherapy, as IMRT and VMAT, require more monitor units and it is important to develop specifically designed shielding materials. METHODS Arraela S.L. has developed new concrete (CONTEK®-RFH2), which is made from an arid with a high p...

Purpose – The purpose of this paper is to focus on optimization of recycling of concrete from lightweight aggregates containing expanded glass and hard polyurethane (PU) and on the issue of importance of environmental management in constructions, to produce the new combination using rest, construction waste of concrete from lightweight aggregates and hard PU new raw components of concrete from ...

Safety control of concrete dams is required due to the potential great loss of life and property in case of dam failure. The purpose of this paper is to feed back the operational control loads for concrete dam displacement using the maximum entropy method. The proposed method is not aimed at a judgement about the safety conditions of the dam. When a strong trend-line effect is evident, the meth...

The flexural behaviour of concrete containing Foamed glass as partial replacement of coarse aggregate is investigated. The coarse aggregate was replaced with 0%, 25%, 50%, 75% and 100% Foamed glass. All other constituents were maintained the same. Reinforced concrete beams were cast using 2 bars of 8mm in diameter in the tensile zone. The density and compressive strength of concrete decreased a...