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Showing posts from December, 2022

The Calculation of the Parameters of Buildings Protection from Radon

  Abstract Radon-222 and its progeny can accumulate in the lower floor premises and harm the people respiratory organs. One of the challenges for the construction industry is to provide indoor radon concentrations that are not much different from its concentrations in the outdoor air. The article proposes an approach to ensuring the buildings radon safety by the passive protective technologies. Its essence is in the determination at the design stage of the required radon protection characteristics of the building underground shell, which performs load-bearing functions and at the same time limits the radon flux from the soil air. Read More about this article: https://irispublishers.com/ctcse/fulltext/the-calculation-of-the-parameters-of-buildings-protection-from-radon.ID.000674.php Read More about Iris Publishers Google scholar Articles : https://scholar.google.com/citations?view_op=view_citation&hl=en&user=LoZ6uCQAAAAJ&cstart=20&pagesize=80&citation...

Carbonation Processing and Characterization of Fly Ash-Portlandite Blends as Cement-Free Binding Agents

  Abstract Carbonation of fly ash mortars augmented with portlandite (CH) under ambient conditions to produce cement-free binding agents that sequester CO 2  is discussed. Fly ash-CH blends are proportioned to produce shape-stable mixtures that can be conventionally cast or extruded. The strength and CO 2  uptake are noted to strongly depend on specimen saturation. High-Ca fly ash blended with 10% CH (by mass) results in a 7-day compressive strength of more than 35 MPa when carbonated, which is ~40% higher than that of the conventionally cured mixture, and a CO 2  uptake of ~8% by mass of the binder. Low-Ca fly ash blended with 30% CH results in 15 MPa strength, which is 3 times higher than that of the conventionally cured mixture, and a CO 2  uptake of ~16% by mass of the binder. The proportion of initial voids that remain after carbonation or conventional curing, which scales well with compressive strength, is shown to be a convenient measure to quantify the r...

Mobile Modular Systems of Water Treatment and Storage in Crises – Solutions used Depending on the Type of Threats

  Abstract Various methods of water purification aim to obtain such a purity class that makes it suitable for consumption are presented in the article. It is a review of solutions, ranging from methods known and used for over 100 years, through research and experiments underway, to only a concept. Some of the solutions are so effective that they should also be combined with safe storage of purified water. Flexible tanks are used for this, which significantly improve logistics and provide a supply of water in all places where it is needed. Depending on whether the lack of drinking water results from a sudden change in the situation resulting from a natural or technical disaster, or whether it is a continuous state, e.g., from prolonged drought, a drastic reduction in water quality or its lack due to permanently damaged or non-existent water supply infrastructure, each of the described cases requires the use of different solutions, which will be described in the article based on solu...

Value of Reservoir Operation Coordinating in Hydropower Enhancement for Roseires and Sennar Dam System in Sudan

  Abstract Increasing the economic profit from reservoir operation in a case study on Blue Nile River in Sudan is the aim of this research short communication. An already developed model that optimizes the coordinated reservoir operation is used to obtain maximum profit from energy generation in a two-reservoir system, i.e., Roseires and Sennar Dam System through the reservoir operation coordinating. An economic crop pattern mix along with two energy generation scenarios in normal year condition are analyzed. Results show that with existing facilities and reservoir operation coordination, 89.5 M$ marginal profit can be obtained, by 280 MW power capacity of Roseires and planned future 50 MW power capacity at Sennar Dam. Model later optimizes the required power capacity and power flow to determine the maximum energy generation in this system. Model shows that in such conditions power capacity of Roseires and Sennar dam can be increased by 528 MW and 568 MW, respectively, to produce 4...

Vesicular Material for Reducing Expansion of Soils

  Abstract Soils with expansion problems have volumetric deformations due to changes in its humidity. There are several soil improvement techniques that consist of materials that react chemically with clay soil or materials that encapsulate the clays to isolate them from water. This work presents a physical alternative based on the use of natural vesicular materials to reduce the change in soil volume. It is concluded that the decrease in expansion of soils using natural void structures like scoria depend on its amount of void volume. This study showed that the volume corresponding to the decrease in expansion required in a soil is equivalent to approximately half of its hollow volume within the soil. Read More about this article: https://irispublishers.com/ctcse/fulltext/vesicular-material-for-reducing-expansion-of-soils.ID.000679.php Read More about Iris Publishers Google scholar Articles : https://scholar.google.com/citations?view_op=view_citation&hl=en&user=...

2021 Sea level rise projections by the Intergovernmental Panel on Climate Change for Coastal Design

  Introduction The Intergovernmental Panel on Climate Change (IPCC) delayed its normal six-year publication cycle of climate assessments after its Fifth Assessment Report (AR5) was published in 2013 [1] because there was an explosion of research on climate change that needed to be evaluated. IPCC’s full Sixth Assessment Report (AR6) will be published in 2022. However, in August 2021, IPCC published the portion of AR6 [2] that deals with the physical basis for climate change including sea level rise. IPCC [2] was supported by updated projections of the contributions of Antarctica [3] and Greenland (The Ice Sheet Mass Balance Inter-Exercise 2020) to sea level rise. IPCC [2] has been per reviewed extensively with the first draft receiving comments from 750 reviewers and the second draft from 1279 peer reviewers [4]. IPCC [1] used temperatures that were projected for 2100 based on Representative Concentration Pathways (RCPs) that describe different climate-scenario futures. Scenario la...

Discussion of Fiber Bragg Grating Technology Applicability on Diagnostic Field Testing of Steel Girder Bridges

  Abstract The application of Fiber Bragg Grating (FBG) technology for purposes of diagnostic field testing on steel girder bridges is discussed in this paper based on the authors experience in field tests of highway bridges. The primary benefit of the FBG technology is the ability to have many sensors (strain gages) multiplexed in a single fiber optic line. In practice, the FBG system is problematic for field conditions of a typical highway bridge. In field tests, measured FBG data showed that the strain histories obtained for a load immediately above the girder of interest were accurate, but the accuracy of the strain histories decreases for adjacent girders as the transverse distance from the load increased. Moreover, protective measures are necessary for FBG systems to be utilized in highway bridge field testing. Read More about this article: https://irispublishers.com/ctcse/fulltext/discussion-of-fiber-bragg-grating-technology-applicability-on-diagnostic-field-testing-of-...