Construction Technologies and Architecture Vol. 5

Abstract: Plastic is now regarded as the third most polluting waste source on a global scale, with its volume rising rapidly as the global population increases. Recycling plastics will help prevent serious environmental threats and add value to plastic waste by incorporating them into various applications, such as construction. Previous research primarily focuses on the investigation of replacing aggregates with plastic wastes in manufacturing concrete. There is a lack of study pertaining to the partial replacement of fine aggregates with plastic waste in producing PPB. In this study, PPB is produced by partially replacing fine aggregates with HDPE and PP plastic wastes. Results show that the 15% HDPE and 15% PP plastic waste replacement of fine aggregates exhibited maximum compressive strength at 11.1 MPa and 9.9 MPa, respectively. The maximum average density recorded was 2678.026 kg/m3, which shows a 23.95% increase compared to the reference block. Additionally, the replacement improved the infiltration rate of PPB, recording a maximum increase of 10% plastic waste replacement. The PPB with 15% HDPE replacement is identified as the optimum mixture and is best utilized in low-traffic areas.

Abstract: Cardava banana pseudostem fibers (BPFs) are recently explored as a composite reinforcement. This is due to its improved thermal and mechanical stability effects for concrete applications. Silica, derived from sodium silicate and a modification additive, was explored as potential matrix in the self-healing applications. Herein, BPFs were prepared to produce BPF – silica composite (BPFSC) as concrete additive. The investigation focused on the interfacial adhesion of BPFs in the silica matrix to self-heal the concrete when subjected to cracks. The synthesized BPFSC has a sheet-like and a rough surface morphology based on the SEM micrographs. BPFs (100 mesh) were used to reinforce silica, and the synthesized composite (BPFSC) was mixed in a cementitious matrix (5% w/w) to test its potential self-healing properties. Results showed that the addition of the silica (SiO₂) improved the mechanical properties of concrete in both the pristine condition and healed samples. Notably, the BPFSC showed better mechanical performance than SiO₂ alone. This explained the good interfacial adhesion of BPF in the BPF – silica matrix. Hence, the prepared composite embedded in concrete showed significant healing potential concerning compressive and tensile strengths after damage, surpassing control specimens. Finally, a synthesis procedure was developed to prepare cardava banana pseudostem fiber – silica composite, showing a potential upcycling route of waste pseudostems for construction materials.

Abstract: Concrete is extremely vulnerable to crack formation. However, repair and monitoring can be labor-intensive and costly. The investigation focused on the augmentation of natural fiber-silica composite-containing concrete’s mechanical properties. Raw coconut husk fiber (CHF) was used to mix with sodium metasilicate, and the synthesized coir-silica composite (CSC) was mixed in a cementitious matrix to test its self-healing properties. The synthesized composite (CSC) has a sheet-like morphology, whereas the silica has a rough surface morphology based on the SEM-EDX micrographs. The presence of silica improved the thermal stability of the raw coconut husk fiber (CHF). Results demonstrated that both pristine condition and healed samples had enhanced mechanical properties with the addition of the CSC material. Hence, the produced composite embedded in concrete surpassed control specimens in terms of healing capability for compressive and tensile strengths after damage. Finally, a synthesis method was developed to prepare a coconut husk fiber-silica composite, demonstrating a viable upcycling route for coconut husks waste utilization.

Abstract: Natural fiber as a fiber reinforcement enhances the high-performance cement composites' strength, ductility, and durability requirements for a concrete application. This study aims to utilize an indigenous natural fiber-silica composite as an additive to cement. Pre-treated durian fibers extracted from durian rinds (100 mesh) were mixed with sodium metasilicate (Na₂SiO₃), and the synthesized durian rind fiber-silica composite (DRFC) was utilized as a cement mass replacement (5% w/w) on concrete to test its effect to mechanical properties. SEM-EDX micrographs show that silica has a rough sheet-like morphology similar to DRFC. However, DRFC also contains a rough fibrous structure indicating the uniformly distributed durian rinds fiber (DRF) present in the composite matrix. Additionally, the presence of silica significantly improves the thermal stability of DRF. Results demonstrated that both concrete with DRF and DRFC additives have superior mechanical properties, surpassing the controlled specimens. Hence, the potential application of DRF to concrete demonstrates a viable upcycling route for durian rinds waste.

Abstract: The article is devoted to the problem of reducing energy consumption in the production of building materials and the operation of buildings by replacing the traditional wall material with more efficient material such as lightweight concrete based on the porous filler of glass granulate (foamed glass granulate concrete) and mineral wool mats, as well as the analysis of the thermal stability of enclosing structures with non-stationary heat flow. Much attention is paid not only to the energy efficiency of systems providing microclimate but also to the efficiency of capital construction, since the development of market relations in the economy has led to a significant increase in the prices for all types of energy carriers. The right shape tuff has been applied in Armenia for the wall material, obtained by sawing mechanically from a rock mass, which in modern construction becomes ineffective, as the thermal technical requirements for building envelopes have become tougher. During the mining of the rock, huge amount of wastes have been accumulated that have valuable properties and can serve as raw materials for obtaining building materials according to energy-saving schemes because of their activity. The issue of disposal of these wastes, which are of great importance both from an economic and environmental point of view, is considered. Given that building materials, products and structures account for 50÷60% of construction costs, the choice of energy-efficient, environmentally friendly building materials will significantly reduce construction costs and lower operating costs. Clinker-free binders have been developed on the basis of cement-free concrete of cellular and conjoint structure using the inherent activity of the rock and by means of energy-saving technologies. In these article thermal technical requirements for enclosing construction in some developed countries and the classification of buildings in terms of energy saving are considered. The ways to improve the energy efficiency of buildings in Armenia are considered taking into account the duration of the heating season with the thermal resistance required ranges from 1.8 to 4.6 (m^2oC) /W. In the view of the peculiarities of climatic conditions in Armenia it is not possible to limit only by indicators of thermal resistance, it is necessary to take into account the heat absorption, thermal stability and thermal inertia of materials. Based on the calculations found that in the structure of construction the lowest fluctuation in temperature takes place with mineral wool mat A_τ=0.167°C, and the largest - concrete on foam glass granulate A_τ=0.381 °C, in addition, a change in the temperature of the outside air does not immediately affect the change in temperature on the inner surface of the structures, since there is a time deviation between a concrete on foam-glass granulate which is 7.16 hours and mats on mineral wool - 8.44 hours.

Abstract: The Philippines is hit by different calamities and is considered one of the world's most disaster-prone countries, regularly ranking in the top three countries hit most by natural catastrophes. Foldable shelters provide private and secure living spaces for persons forced to leave or lose their usual housing due to a calamity. This study aimed to design a lightweight steel-framed temporary shelter that can withstand typhoon calamities and follows the design requirements mandated by the National Building Code and National Structural Code of the Philippines. The shelter's design concept emphasized its expandability, allowing it to accommodate one family of 4-5 persons. It also is designed to be deploy easily, safe, and efficient in post-disaster settings. The major factors considered when developing the shelter are the ease of assembly process, a compact and flexible structure, and adaptability to rapidly changing conditions. The structural analysis indicates that it can withstand a typhoon with an average wind speed of 220 kph but will fail in a super typhoon like Haiyan, with an average wind speed of 250 kph. Since this shelter is designed for temporary uses, the maximum wind capacity of 220 kph is acceptable and can be a reasonable basis for using these to replace other shelters.

Abstract: The vertical growth of cities is a general phenomenon in many countries, aiming to address a more efficient use of space, due to the high cost of the urban area. In the Dominican Republic, approximately 11% of households are apartment buildings, being the second predominant group of residential buildings. According to the National Statistics Office (ONE), the construction of this type of residential buildings is growing significantly, especially in the biggest city of the country. This research has analyzed the interior thermal behavior of these types of households using DesignBuilder®, an energy and environmental simulation software, searching for passive alternatives to allow the reduction of interior temperatures, as a result of overheating because of the tropical climate conditions. The most common type of four levels buildings have been analyzed in this study, through the evaluation of different parameters, such as the optimal orientation, the effect of using sunshades in the windows, and the modification of the building envelope. The objective of the study if to identifying the best alternatives to achieve the thermal comfort of the building, without the use of active control climate techniques such as air conditioning.