نشریه عمران و پروژه
پیاپی 7 (آذر 1398)

Solid waste is one of the problems of urban management. Total solid municipal waste on the Earth in the last year was 1.3 billion tones, increasing every year. Waste management and the strategy of its application is one of the major concerns in most countries. Landfill and waste incineration are two essential solutions for solid waste disposal in the world. Lack of proper land, high cost, multiple strict rules, public opposition to the construction of landfills and environmental pollution are the factors make researchers prefer waste incineration instead of land fill. Municipal solid waste incineration is one of the most environmentally friendly practices can significantly reduce the volume of household waste by up to 90% so it plays an important role in the environment. The products of this method are fly ash and bottom ash of incinerated wastes in incineration plants. In early 1970s reports on the use of municipal solid waste ash in asphalt was issued. In 1980s a number of asphalt centered projects included municipal solid waste ash was done. The purpose of this study is to optimize the use of municipal solid waste ash and prevent environmental damage and expand landfills. In this study, the possibility of using fly ash as an admixture for asphalt bitumen and pavement substrates was investigated and the results showed that it is possible to use fly ash and incinerated bottom ash as substituted materials such as filler or fine particles for asphalt aggregation and has a great impact on improving the physical and chemical properties of asphalt and will also be effective in solving landfill problems.

Given the growing demand for lightweight concrete research to obtain optimal results from lightweight concrete is inevitable. In this study, the influence of steel fibers, polypropylene and glass on the tensile strength, compressive strength and water absorption (durability) of lightweight concrete is investigated. For this purpose, initially 10 basic mixing schemes in which all the properties of the fixed materials and only the percentage of fibers were changed, and one design as the reference mixing scheme (concrete without fibers) were developed. After selecting the control design, the tests of compressive strength, tensile strength, percentage Water absorption (durability) was performed on the samples at 7 days and 28 days. According to the results, it can be concluded that steel fibers are very useful in increasing the compressive and tensile strength of lightweight plastic containing fiber, which in some stages of testing increases the compressive and tensile strength of concrete by more than 40% but poly fibers Propylene and glass, due to their physical and physical properties, are most effective in reducing the percentage of water absorption or increasing the durability of concrete in corrosive environments, although they have a slight effect on the compressive and tensile strength of concrete.

Natural hazard analysis can be a useful tool in deciding, planning and prioritizing crisis management actions. This study provides a correct overview of the proposed strategies in the field of crisis management with a preventive approach.

The construction industry, as one of the industries that has the tier of payment in the state budget bill, has always been the focus of attention of the country's authorities. Lack of financial resources and, on the other hand, inflation in the country, which increases the cost of hospital plans, increases construction time, makes the project economical and loses stakeholder confidence. Identifying the reasons for increasing construction time and controlling inflation can increase the chances of completing hospital plans and avoid increasing costs.