scholarly journals Influence of Groundwater pH on Water Absorption and Waterproofness of Polymer Modified Bituminous Thick Coatings

Materials ◽  
2021 ◽  
Vol 14 (9) ◽  
pp. 2272
Author(s):  
Barbara Francke ◽  
Maria Wichowska
Keyword(s):  
Water Absorption ◽  
Construction Industry ◽  
Surface Damage ◽  
Moisture Susceptibility ◽  
Ph Values ◽  
Demineralized Water ◽  
Construction Products ◽  
Influence Of Water ◽  
Water Ph ◽  
Thick Coatings

Polymer modified bituminous thick coatings are increasingly used in the construction industry to protect underground parts of buildings from groundwater. When assessing their durability, one vital issue related to their functional properties is the influence of water absorption on the waterproofness of the applied solution as a result of the action of groundwater with different pH values. As part of the research, the water absorption of the products in question was assessed using the method of total immersion in water with pH of 4.0, 7.0 and 7.5 as well as comparatively, as a result of one-way exposure to demineralized water under successively increasing pressure up to 0.5 MPa. The moisture susceptibility of the coatings was assessed both concerning the local surface damage and the continuous waterproofing coating. It was established that the coatings show the highest water absorption when the water pH is 4.0, which simulates the groundwater aggressiveness on construction products. It was proven that moisture absorbed by the coatings is retained within this layer and is not transferred to the substrate on which the coatings are laid. It was also found that water in contact with the tested coatings changes its reaction to alkaline, which can result in contamination of groundwater in the area of waterproofing coating. A modification of the method of assessing the water absorption of polymer modified bituminous thick coatings was proposed, taking into account their use in conditions of use.

Influence of Water Absorption on The Selected Properties of Hemp Hurds Composites

2015 ◽  
Vol 10 (1) ◽  
pp. 123-132
Author(s):  
Lucia Kidalova ◽  
Nadezda Stevulova ◽  
Eva Terpakova
Keyword(s):  
Water Absorption ◽  
Influence Of Water

CONSIDERATION OF MODELS AND MECHANISMS OF PUBLIC ADMINISTRATION OF PROCUREMENT OF GOODS, WORKS AND SERVICES IN CONSTRUCTION IN UKRAINE

2018 ◽  
Vol 1 (13) ◽  
pp. 131-142
Author(s):  
Tetyana Konstantinovna Mitropan
Keyword(s):  
Public Administration ◽  
Construction Industry ◽  
High Efficiency ◽  
Public Procurement ◽  
Combined Model ◽  
Single Body ◽  
Construction Products ◽  
Model Of Management ◽  
Decentralized Model ◽  
Centralized Model

The article presents the questions of reviewing models and mechanisms of public administration in the procurement of goods, works and services in the field of construction. A comparative analysis of the types of public procurement mechanisms in construction, based on a set of features, has shown the superiority of a centralized type of mechanism that facilitates the introduction of efficient and flexible procurement methods, for example, the conclusion of framework agreements. The author’s vision of the mechanism of state building purchases, in the form of a conceptual model and system differences, is proposed. It is determined that a decentralized model of public procurement management involves the independent implementation by purchasers of procurement, that is, allows each customer to procure goods, works and services in the field of construction. The centralized model of public administration is characterized by the implementation of public procurement in order to provide the general needs of a single body on public procurement, that is, customers commission the implementation of public procurement on their behalf, a centralized body. According to the combined model of management, public procurement in the construction industry takes place under contracts implemented under the centralized model, and the direct ordering and receipt of goods, works, or services takes place according to the rules of a decentralized model. It is noted that according to the system-wide understanding of the mechanism of public administration in the procurement of goods, works and services in the field of construction, it represents a set of specialized management technologies (methods, techniques and tools) that ensure the organization of the process of public procurement of construction products by authorized agents. The direction of this process is determined by the need to implement the principles of vali- dity and innovation, fair choice of the best bidding, prevention of corruption and ensuring the high efficiency of the implementation of public public procurement.

Effect of Cyclic Exposure of Chemicals on Compressive Strength of Polyester Resin Based Polymer Concrete

2013 ◽  
Vol 687 ◽  
pp. 185-190 ◽  
Author(s):  
Masoud Jamshidi ◽  
Mohammad Javad Ghasemi ◽  
Abdolreza Hashemi
Keyword(s):  
Compressive Strength ◽  
Construction Industry ◽  
Polyester Resin ◽  
Unsaturated Polyester ◽  
Concrete Structures ◽  
Polymer Concrete ◽  
Acid Solutions ◽  
Gas Oil ◽  
Demineralized Water ◽  
Concrete Production

Polymer concretes (PC) were introduced to building and construction industry more than 50 years ago. Gradually, they became a suitable substitute for concrete structures. Their superior properties againt aggresives introduced them as a good overlay for concrete structures; however, their application was shortly diminished due to the higher costs. In this research a homemade cost-quality effective resin (unsaturated polyester) is used as binder in the polymer concrete production. Polymer concrete specimens were evaluated for compressive strength and its fluctuation due to cyclic exposure to different aggresive solutions (sulfuric acid, nitric acid, citric acid, chloridric acid, sodum sulfate, water, demineralized water, sodium hydroxid, potasium hydroxid and gas oil). It was found that PC specimens degraded more in alkali conditioned in comparison to acid solutions.

scholarly journals Development of a Low-Cost pH Meter for Liquid Chemical Fertilizers

2020 ◽  
Vol 8 (4) ◽  
pp. 840-846
Author(s):  
Muhittin Yağmur Polat ◽  
Abdullah Beyaz ◽  
İbrahim Çilingir
Keyword(s):  
Ph Value ◽  
Low Cost ◽  
Ph Sensor ◽  
Field Application ◽  
Average Error ◽  
Chemical Fertilizers ◽  
Modern Agriculture ◽  
Ph Values ◽  
Water Ph ◽  
Liquid Chemical

Liquid chemical fertilizers are widely used in modern agriculture. The pH values of these fertilizers are important in terms of their effectiveness in the field application and their effect on the soil-water pH balance. Therefore, it is necessary to measure the pH and other properties of liquid fertilizers with fast, practical and inexpensive methods. With the advancing technology, pH value has been started to measure more accurately and efficiently with the help of low-cost devices. In this study, a low-cost pH meter was developed using a low-cost pH sensor, an Arduino UNO R3 microcontroller board, and a software written in the C/C++ programming language. The developed pH meter was used to measure the pH values of liquid chemical fertilizers. Close variations were observed between the values obtained from it and the values measured by an accredited, laboratory-type pH meter. According to the pH measurements of the two pH meters, R2 ranged 88.1% to 99.3%, average error range 0.14 to 0.28, and average error percentage ranged 1.56% to 6.81% for three different types of liquid fertilizers. In light of these results, it was shown that the developed low-cost pH meter can be useful for practical pH measurement applications.

scholarly journals Features of Non-Tariff Regulation of Construction Products Market in Ukraine

2019 ◽  
Vol 8 (4S) ◽  
pp. 15-19
Keyword(s):  
Construction Industry ◽  
Health And Safety ◽  
Legal Framework ◽  
State Regulation ◽  
Market Regulation ◽  
The European Union ◽  
National System ◽  
Construction Products ◽  
Quality Of Products

The article deals with the issue of state regulation over the construction products industry. Analysis resulted in the identification of two main forms of regulation: tariff and non-tariff regulation. Global practices show the effectiveness of non-tariff regulation in the construction industry. Being a WTO member, Ukraine has to implement the legal framework of non-tariff regulation, in regards to those aspects contributing to compliance with the rating and standards of the European Union to ensure the quality of products. The main objective of non-tariff market regulation is to ensure the quality of finished products, environmental protection, health and safety of life. The national system of regulation, including technical rate-setting of the construction products manufacturing must comply with the international documents ratified by Ukraine. The article analyzes the domestic legal framework and proposes an algorithm for designing a national system of non-tariff regulation in accordance with international rules and standards.

scholarly journals Effects of spray-dried sourdough on flour characteristics and rheological properties of dough

2013 ◽  
Vol 31 (No. 4) ◽  
pp. 361-367 ◽  
Author(s):  
A.G. Tafti ◽  
S.H. Peighardoust ◽  
F. Behnam ◽  
A. Bahrami ◽  
R. Aghagholizadeh ◽  
...  
Keyword(s):  
Water Absorption ◽  
Development Time ◽  
Ph Values ◽  
Powder Addition ◽  
Dough Extensibility ◽  
Dough Development Time ◽  
Wheat Flours ◽  
Different Levels ◽  
Control Water ◽  
Spray Dried

The effect of incorporating different levels of spray-dried sourdough (3, 6, 9, and 15% w/w) on flour characteristics and dough properties of two wheat flours was studied. As the spray-dried sourdough level in the blends increased, the pH values significantly (P < 0.05) decreased. Wet gluten content and sedimentation values were decreased in the flours containing spray-dried sourdough compared to those of the control. Water absorption significantly increased compared to that of the control. However, the dough development time was not affected by sourdough powder addition. Degree of softening significantly increased with an increase in the sourdough level and dough stability was significantly reduced. Doughs incorporating sourdough powder showed higher resistance to extension and lower dough extensibility than the control doughs.  

scholarly journals The Application of 3D-Printing Techniques in the Manufacturing of Cement-Based Construction Products and Experiences Based on the Assessment of Such Products

Buildings ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 144
Author(s):  
Guillermo Sotorrío Ortega ◽  
Javier Alonso Madrid ◽  
Nils O. E. Olsson ◽  
José Antonio Tenorio Ríos
Keyword(s):  
3D Printing ◽  
Construction Industry ◽  
Material Consumption ◽  
Construction Products ◽  
International Projects ◽  
Substantial Progress ◽  
3D Printed ◽  
Materials Used ◽  
Printing Techniques

The construction industry has embraced digitisation and industrialisation in response to the need to increase its productivity, optimise material consumption and improve workmanship. Additive manufacturing (AM), more widely known as 3D printing, has driven substantial progress in these respects in other industries, and a number of national and international projects have helped to introduce the technique to the construction industry. As with other innovative processes not covered by uniform standards, appropriate assessments and testing methodologies to control the quality of the 3D-printed end products, while not obligatory, are advisable. This article shows that regulation is not an obstacle to the use of an innovative product, such as 3D printing, by proposing quality-control tests and an assessment methodology, in the understanding that standardisation ensures the viability of a technology. The information, including the methods and results, is based on the authors’ experiences in the development of three research projects pertaining to 3D printing. This paper also discusses whether the performance of the materials used in 3D printing could be superior to traditional ones.

Influence of Water Absorption on Static Friction of Pure and Friction-Modified PA6 Polymers

2019 ◽  
Vol 799 ◽  
pp. 59-64
Author(s):  
Igor Velkavrh ◽  
Stefan Klien ◽  
Joel Voyer ◽  
Florian Ausserer ◽  
Alexander Diem
Keyword(s):  
Water Absorption ◽  
Static Friction ◽  
Polyamide 6 ◽  
Coated Steel ◽  
Friction Modifiers ◽  
Test Conditions ◽  
Influence Of Water ◽  
Steel Surfaces ◽  
Contact Pressures ◽  
Lubrication Conditions

In the present study, static coefficients of friction of pure and friction modified (FM) polyamide 6 (PA6) polymers against primer-coated steel surfaces were investigated under a series of nominal contact pressures and by considering the influences of water absorption by the polymer, temperature, counter-body surface roughness and lubrication conditions. Under the majority of the test conditions investigated, FM PA6 exhibited lower static friction than pure PA6. Under unlubricated conditions, this was due to the low adhesion of the FM PA6 provided by its friction modifying inclusions; while under lubricated conditions, a combination of softening due to water absorption and decreased adhesion provided by its friction modifiers enabled lower static friction, especially at medium and high contact pressures.

Sign in / Sign up

Export Citation Format

Share Document