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Ecocritical Interpretation of natural and virtual elements in the residential environment. nature in dwelling spaces and its simulacra

Śliwa Agata

Architecture Civil Engineering Environment

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2023

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Vol. 16, no. 4

59--67

EN

The transformed living space as a symptom of culture remains in regulated relation or opposition to nature. Habitation concerns living beings, humans, as well as animals and plants whose well-being requires appropriate conditions that translate into quality of life. Coexistence with nature is essential from the level of satisfying basic physiological needs to higher ones. Contemporary imitations of natural elements are enhanced by information technologies and their incarnated manifestation – the virtual space, which enables substitute solutions – the simulacra. Dwellings have become multidimensional platforms for everyday activities, combining elements of simultaneous natural and virtual worlds. Research includes ecocritical interpretations of the natural world in architecture, exemplified by the design of a dormitory for the campus of the University of California in Santa Barbara. The aim is to indicate the direction of further development of smart residential architecture marked by modern technologies in an ecological context considering the interdependence of human and nature. The conclusions indicate that balanced natural and virtual elements are compatible but not equivalent.

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The stiffness of steel-wood-steel connection loaded parallel to the grain

Rahim Nur Liza, Raftery Gary, Quenneville Pierre, Ing Doh Shu, Nabialek Marcin, Jaya Ramadhansyah Putra, Ibrahim Norlia Mohamad, Abdullah Mohd Mustafa Al Bakri, Śliwa Agata

Archives of Civil Engineering

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2022

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Vol. 68, nr 2

37--50

EN

In Eurocode 5, the stiffness equation for bolted steel-wood-steel is stated as a function of wood density and fastener diameter only. In this research, an experimental study on various configurations of tested bolted steel-wood-steel (SWS) connections has been undertaken to predict the initial stiffness of each connection. In order to validate the Eurocode 5 stiffness equation, tests on 50 timber specimens (40 glued laminated timbers and 10 laminated veneer lumbers (LVL)) with steel plates were undertaken. The number of bolts was kept similar and the connector diameter, timber thickness, and wood density were varied. The results obtained in the experimental tests are compared with those obtained from the Eurocode 5 stiffness equation. From the analysis, it is signified that the stiffness equation specified in Eurocode 5 for bolted SWS connections does not adequately predict the initial stiffness. The results from Eurocode 5 stiffness equation are very far from the experimental values. The ratio of stiffness equation to experimental results ranges from 3.48 to 4.20, with the average at 3.77, where the equation overpredicted the experimental stiffness value for the connection. There is a need to consider or incorporated other parameters such as geometric configurations in Eurocode 5 stiffness equation to improve the ratio with the experimental data.

3

The impact of microwave treatment on the chemical properties of sewerage sludge

Ing Doh Shu, Jaya Ramadhansyah Putra, Ho Chia Min, Chin Siew Choo, Nabiałek Marcin, Abdullah Mohd Mustafa Al Bakri, Garus Sebastian, Śliwa Agata

Archives of Civil Engineering

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2022

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Vol. 68, nr 1

365--377

EN

Due to urbanization, the population in the major cities in Malaysia is approximately 72.8% of its total population. The increase of population density has directly increased the amount of sewerage sludge waste that poses threat to the environment. In line with the green initiatives, alternative method to develop good quality concrete material from sewerage sludge waste can be further explored. Traditionally, sewerage sludge waste is processed using incinerator that require high energy and it is time consuming. In this study, microwave heating which require less energy consumption and less time consuming is used for sewerage sludge preparation. Prior to heating process, sewerage sludge waste is over dried at 105°C for 24 hours. Three types of microwave heating namely medium heating, medium high heating and high heating has been used. The chemical and physical properties microwaved sewerage sludge ash (MSSA) was tested using X-Ray Fluorescence (XRF), X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM). Based on the result, the recommended temperature for the MSSA production for the concrete is High Mode Temperature. This is due to the result of MSSA for X-Ray Fluorescent test as its shows the highest in the content for pozzolanic element which are SiO2 and Fe2O3 that produce after the microwave burning process. The mineralogical composition and the crystalline phase of the High temperature MSSA due to X-Ray Diffraction test also shows high content of SiO2 as the major component as it is good for pozzolanic reaction in concrete. From the Scanning Electron Microscope test, it is observed that particle of High heated MSSA are slightly smaller than other temperature. Also, the densification occurs at High temperature MSSA. Hence, the optimal burning temperature mode for MSSA is High Mode temperature.

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Marshall stability of porous asphalt mixture incorporating kenaf fiber

Jasni Nur Ezreen, Masri Khairi Azman, Jaya Ramadhansyah Putra, Abdullah Mohd Mustafa Al Bakri, Razak Rafiza Abd, Nabiałek Marcin, Błoch Katarzyna, Śliwa Agata

Archives of Civil Engineering

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2022

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Vol. 68, nr 1

379--393

EN

Porous asphalt mixture (PA), known as open-graded surfaces over a stone bed underneath, allows water to go through. These factors can affect the porous asphalt mixture adhesive strength. The high amount of course aggregate promotes the structure of air voids have certain impacts on the acoustic properties of porous asphalt. The materials properties are consisting of both aggregate and bitumen tests. This study also details out the aggregates sieve analysis test to develop new aggregate gradation for PA. According to five ASEAN countries’ specifications, the sieve analysis test was done. The countries included are Malaysia, Vietnam, Thailand, Singapore, and Indonesia. The test for the binder includes the softening point, penetration, and ductility. This study also investigates the addition of kenaf fiber in the mixture as an additive. Mechanical performance test for PA using Marshall Stability test to identify the strength and the properties of the conventional PA with the addition of kenaf fiber compared to the new gradation of PA incorporating kenaf fiber. From the results, the addition of 0.3% kenaf modified PA improved the performance of PA in terms of Marshall Stability and volumetric properties.

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Effect of Rice Straw Ash (RSA) as partially replacement of cement toward fire resistance of self-compacting concrete

Razak Rafiza Abd, Chin Yi Qin, Abdullah Mohd Mustafa Al Bakri, Yahya Zarina, Ishak Mokhzani Khair, Garus Sebastian, Nabiałek Marcin, Zailani Warid Wazien Ahmad, Masri Khairil Azman, Sandu Andrei Victor, Śliwa Agata

Archives of Civil Engineering

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2022

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Vol. 68, nr 1

353--363

EN

Malaysia’s construction industry is experiencing rapid growth, translating into increased demand for cement. However, cement production pollutes the air to the detriment of the climate via CO2 emission, making research into a cementitious replacement in concrete a necessity. This paper details an experimental study of self-compacting concrete (SCC) with partial replacement of cement by rice straw ash (RSA), which is expected to result in environmental preservation due to the green materials being used in cement production. The physicomechanical properties of the SCC with RSA replacement were determined via its compressive strength, water absorption, self-workability, and fire resistance (residual strength after exposure to high temperatures). The proportion of RSA replacement used were 0%, 5%, 10%, 15%, 20%, and 25%, and all passed the slump flow test, except the 20% and 25% samples. The SCC samples with 15% of RSA replacement reported the highest compressive strength at 7 and 28 curing days and the highest residual strength post-exposure to high temperatures. The lowest percentage of water absorption was reported by the 15% of RSA replacement, with a density of 2370 kg/m3

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Crumb rubber geopolymer mortar at elevated temperature exposure

Azmi Ahmad Azrem, Abdullah Mohd Mustafa Al Bakri, Ghazali Che Mohd Ruzaidi, Ahmad Romisuhani, Jaya Ramadhansyah Putra, Rahim Shayfull Zamree Abd, Almadani Mohammad A., Wysłocki Jerzy J., Śliwa Agata, Sandu Andrei Victor

Archives of Civil Engineering

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2022

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Vol. 68, nr 3

87--105

EN

Low calcium fly ash is used as the main material in the mixture and the crumb rubber was used in replacing fine aggregates in geopolymer mortar. Sodium hydroxide (NaOH) and sodium silicate (Na2SiO3) which were high alkaline solution were incorporated as the alkaline solution. The fly ash reacted with the alkaline solution forming alumino-silicate gel that binds the aggregate to produce a geopolymer mortar. The loading of crumb rubber in the fly ash based geopolymer mortar was set at 0% (CRGM-0), 5% (CRGM-5), 10% (CRGM-10), 15% (CRGM-15), and 20% (CRGM-20), respectively. NaOH solution (12M) and Na2SiO3 solution ratio is set constant at 2.5 for all geopolymer mixture and the fly ash to alkali activator ratio was kept at 2.0. The CRGM at 28 days of curing time was exposed to elevated temperature at 200ºC, 400ºC, 600ºC and 800ºC. The weight loss of the CRGM increases with increasing temperature at all elevated temperatures. However, the density and compressive strength of CRGM decrease with an increase of crumb rubber loading for all elevated temperature exposure. The compressive strength of CRGM reduced due to the fact that rubber decomposes between 200ºC and 600ºC thereby creating voids. CRGM-15 and CRGM-20 showed cracks developed with rough surface at 800ºC. Image obtained from scanning electron microscope (SEM) showed that, the CRGM changed significantly due to the decomposition of crumb rubber and evaporation of the free water at 400ºC, 600ºC and 800ºC.

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Compressive strength and durability of foamed concrete incorporating Processed Spent Bleaching Earth

Othman Rokiah, Muthusamy Khairunisa, Sulaiman Mohd Arif, Duraisamy Youventharan, Jaya Ramadhansyah Putra, Wei Chong Beng, Abdullah Mohd Mustafa Al Bakri, Mangi Sajjad Ali, Nabiałek Marcin, Śliwa Agata

Archives of Civil Engineering

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2022

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Vol. 68, nr 2

627--643

EN

Foamed concrete incorporating processed spent bleaching earth (PSBE) produces environmentally friendly foamed concrete. Compressive strength, porosity, and rapid chloride penetration tests were performed to investigate the potential application for building material due to its low density and porous concrete. Laboratory results show that 30% PSBE as cement replacement in foamed concrete produced higher compressive strength. Meanwhile, the porosity of the specimen produced by 30% PSBE was 45% lower than control foamed concrete. The porosity of foamed concrete incorporating PSBE decreases due to the fineness of PSBE that reduces the volume of void space between cement and fine aggregate. It was effectively blocking the pore and enhances the durability. Consistently, the positive effect of incorporating of PSBE has decreased the rapid chloride ion permeability compared to that control foamed concrete. According to ASTM C1202-19 the foamed concrete containing 30% PSBE was considered low moderate permeability based on its charge coulombs value of less than 4000. Besides, the high chloride ion permeability in foamed concrete is because the current quickly passes through the specimen due to its larger air volume. In conclusion, incorporating PSBE in foamed concrete generates an excellent pozzolanic effect, producing more calcium silicate hydrate and denser foamed concrete, making it greater, fewer voids, and higher resistance to chloride penetration.