High Durability Properties Research Articles

EFFECTS OF GUM ARABIC ON THE MOISTURE CONTENT AND WATER ABSORPTION OF LATERITIC BRICKS OF VARYING PARTICLE SIZES OF FINE AGGREGATES

The increasing greenhouse gas emissions associated with construction, accounts for 37% global emissions. In mitigating these challenges, the Nigerian Building and Road Research Institute (NBRRI) recommends the use of lateritic bricks due to it's environmental sustainability. To achieve durability and environmental sustainability, Gum Arabic is introduced in laterite soil to improve its properties. The objective of the study is to determine the suitability of Gum Arabic as stabilizer on the moisture content and water absorption capacity of earth bricks of different particle size distributions. Experimental research method was adopted for the study. The particle size distribution of the laterite soil was classified within the ranges 75µm-600µm, and 1.18mm- 4.76mm. Also, the content of the Gum Arabic was proportioned from the range of 0% to 30% partial replacements. Sample bricks were produced and tested at 14, 21 and 28 days curing period. The data collected from the results of the laboratory experiments was analysed using bar charts. The results showed that, particle size distributions for grading fine aggregate suitable for compressed stabilised earth bricks (CSEB) was found to be between 1.18mm-4.76mm considering it low extent of permeability and high durability properties at 28 days curing period. It was concluded that, moisture content influences the rate of water absorption, such that an increase in moisture content consequently increases the rate of water absorption. However, the low extent of water permeability recorded, reduces the water content in the pores of the CSEBs, thereby reducing the extent of expansion and contraction making the GA-based CSEBS to be less brittle and more durable. It was recommended that, when selecting eco-friendly bricks for construction of buildings, Gum Arabic based Compressed Stabilised Earth Bricks (GA-based CSEBs), should be utilised considering its low permeability and durability for particle size ˃ 600µm.

Antimicrobial, anti-biofouling, antioxidant, and biocompatible fabrics with high durability via green growth of trimetallic nanoparticles

There is a high demand for green and sustainable multifunctional fabrics, which find application in a variety of real-life contexts. This study addresses the development of antimicrobial, antioxidant, anti-biofouling and biocompatible fabrics through a one-step, versatile and cost-effective in-situ green growth strategy. Monometallic, bimetallic and trimetallic nanoparticles comprising silver (Ag), copper (Cu) and zinc (Zn) were grown in-situ on fabric surfaces using Sideritis scardica extract. The average size of nanoparticles was 99 ± 25 nm, 131 ± 29 nm, 68 ± 18 nm for Ag, Cu and Zn. The metallic nanoparticles grown on the fabric surface imparted a range of colors to the fabrics, including yellow, brownish and greenish hues. Nanoparticle-decorated fabrics have antimicrobial, antioxidant, anti-biofouling, biocompatibility, and high durability properties. The decoration of fabrics with metallic nanoparticles mediated antimicrobial properties against bacteria (E. coli and S. aureus) and fungi (C. albicans), achieving a reduction of over 99.99 % (Logarithmic reduction>4). Bimetallic and trimetallic Ag and Cu nanoparticles exhibited enhanced antifungal activity in comparison to their monometallic counterparts. The cytotoxic effects of Cu were effectively eliminated through the fabrication of bimetallic nanostructures containing Zn. Notably, the biocompatibility of monometallic and bimetallic combinations involving Ag and Zn exceeded 95 %. The water contact angles of the decorated fabrics ranged from 145° to 153°. The superhydrophobic character of the fabrics prevented pathogen adhesion and inhibited biofilm formation. Moreover, all nanoparticle-decorated fabrics demonstrated antioxidant properties, with radical-scavenging activity ranging from 46 % to 91 %. The fabrics retained their antimicrobial properties against mechanical abrasion, heating and repeated cycles of washing and bending.

An analysis of diffusion mechanism and mechanical properties of jute, JUCO, and banana fiber composites in three different mediums

Natural fiber-reinforced polymer composites (NFRPC) are the most desirable for their low-cost, eco-friendly, and high-durability properties. Scientists are facing numerous challenges with this type of composite in a wet or high-humid environment. High water absorption and reduced mechanical properties are the main concerns for this type of composite. A new kind of fiber mat called JUCO, which is a mixture of jute and cotton, is introduced here. Banana fiber and jute yarn were used to fabricate unidirectional mats, which were made using a custom-designed handloom. The composite fabrication was done by hand layup with the cold press method. The tensile and flexural strengths decreased after immersion in three mediums (pH 3, pH 7, and pH 8) for 150 days due to the water aging effect. Minimum strength was found when the samples were immersed in pH 3 mediums. Tensile and flexural test results were also evaluated by the finite elemental method (FEM) to validate the experimental results. The main objectives of this study are to investigate the mechanical properties and degradation due to the aging of newly developed JUCO fiber-based composites.

ANALYSIS OF PHYSICO-CHEMICAL PROPERTIES OF GEOGRIDS USED FOR THE REINFORCEMENT OF NATURAL AIRFIELD PAVEMENTS

Geogrids applied to reinforce natural airfield pavements are polymer cellular geosynthetics with a spatial, permeable honeycomb structure. Geogrid is used to increase the safety of air operations by improving the load-bearing capacity of unreinforced airfield pavements. Laboratory tests of the applied plastic were one of the stages of verifying the efficiency of the suggested geogrid. Conducted tests showed that the used plastic is useful in manufacturing a geogrid. A geogrid neither deteriorates nor wears after applying a specific load thanks to its high durability properties. The load-bearing capacity of natural airfield pavements reinforced with a plastic geogrid improved by approximately 20%.

Application of ECC as a Repair/Retrofit and Pavement/Bridge Deck Material for Sustainable Structures: A Review.

Concrete structures cannot efficiently perform their functions over time due to chemical and physical external effects. Thus, enhancing the relationship between repair and aged structures, and also improving the durability properties of concrete is crucial in terms of sustainability. However, high costs, negative environmental effects, and incompatibility problems occur in repair/retrofit applications. Furthermore, three-quarters of the failures in the repaired/retrofitted structures are caused by a lack of repair durability. The need for repair in pavement/bridge decks is also frequently encountered, and early-age performance problems with repair materials cause pavement/bridge decks to be unavailable for certain periods of time. Engineered Cementitious Composite (ECC) can be effectively used as repair/retrofit and pavement/bridge deck material. It also has a minimal need for repair/retrofit thanks to its high durability properties. This article presents state-of-the-art research regarding the application of ECC as a repair/retrofit and pavement/bridge deck material. Studies in the literature show that the repair/retrofit properties of ECC outperform conventional concrete and steel fiber-reinforced concrete. ECC can be a solution to high early strength and drying shrinkage problems frequently encountered in the use of repair materials. It could also be used for different repair applications such as cast, sprayed, and trenchless rehabilitation. Moreover, ECC might fulfill specific requirements for pavement, pavement overlay, tunnel pavement, airfield pavement, and bridge deck. These superior performances are attributed to ECC's kink-crack trapping mechanism, uniquely large inelastic strain capacity, strain hardening, high tensile strain capacity, and multiple microcracking and ductile behaviors, especially bonding behavior and self-healing.

Mechanical Properties of Blast Furnace Slag and Rice Husk Ash with Coconut Shell as Partial Replacement of Aggregates

This research showed the application of concrete material in construction industry were highly demand which growing rapidly demonstrate the need for various types and properties of concrete to meet the diverse needs of the user. Normally, the quality of concrete with high durability properties can be generated by consideration of the composition of the materials used such as cement, sand, aggregates or water. Besides that, mix design and the way of production like mixing, transporting and pouring concrete is also the factors to get a better quality of concrete. Recently, the sustainability in construction is one of the efforts that have been practiced by developed countries to create healthier environment and to reduce the environmental impact of a building over its entire lifetime, while optimizing its economic viability and the comfort and safety of its occupants. One of the steps that can be practice is to use materials that are categorized as agricultural waste material such as palm oil fuel ash, rice husk, fly ash slag, sludge, coconut shell and etc. in concrete manufacturing. Hence, the objective of this paper is to evaluate the performance of blast furnace slag, rice husk ash and coconut shell as partial replacement of aggregates in cement. A series of test were conducted to investigate the performance of blast furnace slag, rice husk ash and coconut shell as partial replacement of aggregates in cement. The tests that are being conducted are compressive strength test, flexural strength test, rebound hammer test, ultrasonic pulse velocity test, water permeability test, sieve analysis test, water absorption test, carbonation test, alkali-silica reaction test, SEM test and shrinkage test.

Durability of high belite cement as new technical solution for concrete

The study presents an investigation on the durability performance of concretes produced with an industrial scale high belite cement. This binder, thanks to the high amount of C-S-H gel and the lower C3S/C2S ratio, is characterized by high durability properties. Good resistance to freeze/thaw cycles, very low chloride migration and excellent resistance to sulfate attack were demonstrated. Theaccelerated carbonation test revealed that the belite cement, due to the high C2S phase amount, is able to increase its strength over time when exposed to high CO2 concentration. Durability and strength results were compared with those of CEM I, CEM II, and CEM III. In addition, a comparison of the performance of a self-compacting concrete produced with high belite cement and CEM I (as reference) is also presented. The results show that the self-compacting concrete with the high belite cement is able to reach sufficient strengths already after 1 day of hydration, with a low heat development and improved durability properties, compared to CEM I.

Developing a Sustainable Concrete using Waste Glass and Rubber for Application in Precast Pedestrian Slabs

In this piece of research, n attempt was made to produce a sustainable concrete with the partial replacement of both fine and coarse natural aggregates with two different non-biodegradable wastes. The selected wastes were fine glass and shredded rubber tires. Fine glass passing through 4.75 mm BS sieve was utilised for the partial replacement of fine natural aggregates. Coarse natural aggregates were partially replaced with shredded rubber passing through 20 mm sieve and retained on 6.30 mm sieve. Several mixes with varying % of fine glass but with a fixed 10 % of shredded rubber were tested. Optimum fine glass content was determined to be in the order of 20 %. The resulting concrete exhibited lower plastic and hardened densities (2040 and 2117 kg/m3 respectively) in comparison to normal plain concrete. The static modulus of elasticity was found to be 18.3 GPa (mean value), while the splitting tensile strength was 2.37 MPa. The flexural strength showed a significant increase of 20.3% compared to the control mix. The results concluded that the concrete thus produced is a viable means of disposing of such non-biodegradable wastes (rubber and glass), thus reducing the loads at landfills. This new genre of concrete was produced at a lower cost than normal concrete because of the very low pre-treatment costs of the recycled wastes used. Furthermore, the properties tend to indicate that the concrete could be applied where lower strength and high durability properties are warranted. Hence precast slabs were made from the new design concrete and were tested along a stretch of a highly trafficable pedestrian walkway on the University campus. The slabs were continuously monitored for defects such as cracks, broken corners and slabs for a period of 24 consecutive weeks. After the test period it was observed that only 4 out of the 80 precast slabs had hairline cracks. Hence concluding the enhanced durability properties of the new design concrete. Doi: 10.28991/cej-2021-03091690 Full Text: PDF

Different aspects of polyester polymer concrete for sustainable construction

Polymeric material plays a vital role in construction industry for the past 50 years and there are lot of researches on going in different countries to use the polymers in construction for various applications. Polymer concrete is a type of sustainable concrete which is totally free from cement and water as binder thereby possessing various advantages towards green concrete than conventional Portland Cement Concrete. In this paper, authors developed a mix for polymer concrete using Isophthalic resin of more than 60 MPa compressive strength for manufacturing inspection covers and frames. Developed Polymer concrete possessing various advantages like higher mechanical properties, high durability properties, rapid hardening and very good acid resistant properties can be used in various applications in architecture, construction, chemical, petroleum industries, etc. The different aspects of developed Isophthalic Polyester Polymer Concrete (IPPC), its applications towards sustainable construction in various industries are discussed in this paper.

Characteristics of tools used in the friction drilling method

Friction drilling as a non-chip drilling method require a special formed tool. This tool can be combined with conventional drilling machines as well as milling machines, also CNC ones. The choice depends only on the factors related to production volumes. Tool must have high durability properties to reach proper efficiency level. This means the number of boreholes that can be formed while maintaining the shape and structure of the surface within the dimensions tolerances limits. High temperature in process also cause a high durability properties. These article presents a review of apossible solutions on tools mounting devices and tools functionality used in friction drilling process.

Material design and characterization of high performance pervious concrete

Continued urbanization and population growth further the growth of impervious urban areas, leading to concerning adverse environmental and societal impacts. Pervious concrete has remarkable potential to counteract these adverse impacts while providing necessary structural integrity, thus supporting continued urbanization. Broader application of pervious concrete could be achieved through increased raveling resistance and enhanced durability performance. This research emphasizes the development and characterization of high performance pervious concrete aiming at improved mechanical resistance and advanced durability properties. In pursuit of this goal an ultra-high performance cement-based matrix with compressive strengths in excess of 150MPa (22ksi) and high durability properties are designed and applied to the mixture design concept of pervious concrete. The research results show that compressive strength and elastic modulus increase by up to 150% and 100%, respectively, without sacrificing the hydraulic conductivity of the concrete. Furthermore, freeze–thaw tests have been carried out to compare the durability performance of conventional pervious concrete with high performance pervious concrete. Based on enhanced mechanical properties as well as improved durability, high performance pervious concrete potentially allows extending the application of pervious concrete and thus carries a vital potential in effectively counteracting the growth of impervious urban areas.