bluuebunny/crossref_metadata_2025 huggingface dataset:
Screen printed textile electrodes using graphene and carbon nanotubes with silver for flexible supercapacitor applications
Authors: Keawploy Norawich , Venkatkarthick Radhakrishnan , Wangyao Panyawat , Qin Jiaqian
Published: August 2022

The eco-friendly conductive cotton textile is promising alternatives for the flexible substrates in wearable devices since the cotton is as an inexpensive natural fabric material and compatible in modern portable electronics with adequate electrical conductivity. In this work, flexible conductive cotton-based electrodes are prepared via a screen-printing method using the carbonaceous nanomaterials such as carbon nanotubes (CNTs) and graphene with an additional component of conductive silver (Ag) powder and textile ink. The prepared conductive cotton electrodes exhibit lower sheet resistance (<10 Ω) along with superior mass loading (20-30 mg.cm-2). On the basis of the performance of cotton electrodes prepared, an all-solid-state flexible supercapacitor device was successfully fabricated which exhibits a high specific areal capacitance of 677.12 mF.cm-2 at 0.0125 mA.cm-2 for a suitable electrode composition (60% of Ag and 40% CNTs) using a PVA-KOH gel electrolyte. The flexible device endures a stable electrochemical performance under severe mechanical deformation using different bending angles (0°, 30°, 45°, 60° and 90°) of the device and possesses excellent cyclic stability with the capacitance retention of ~80% even after 3000 CV cycles.
Copper toxicity in plants: a review and a case study on tea
Authors: Saha Dipanwita , Mandal Sima , Saha Aniruddha
Published: August 2022

Copper in trace amounts is essential for various metabolic processes in the plant such as photosynthesis, carbohydrate distribution, and protein metabolism but at high concentration it causes physiological stress through generation of free radicals that induce the production of reactive oxygen species (ROS) via Haber-Weiss and Fenton reactions. Copper-induced generation of hydrogen peroxide, hydroxyl radicals, or other reactive oxygen species has been directly correlated with the damage to protein and lipids that may lead to reduced growth and even death. Tea (Camellia sinensis L. (O.) Kuntze) is an economically important plantation crop in India with round the year productivity. Copper based fungicides are cheap and effective in controlling fungal diseases and are used consistently throughout the year to combat different fungal diseases that pose a major threat to tea production. Excess Cu2+ has been found to alter several physiochemical parameters in the tea plants. A more detailed study on mechanisms of Cu2+ toxicity at the gene level is warranted.
Understanding the functional attributes of different microbial enzymes in bioremediation
Authors: Malakar Neha , Mitra Sreya , Toppo Prabha , Mathur Piyush
Published: August 2022

Bioremediation uses biological organisms and their metabolic processes in order to degrade contaminants present in water, soil etc. Microbes have the vast potential are the major resource for bioprocess of using microbial enzymes reduces the toxicity of pollutants caused by the waste materials like pesticides, insecticides, plastics, other hydrocarbon-containing substances and obtain novel useful substances for mankind and the environment. Enzymes produced by bacteria, fungi, plants play a key role in the biodegradation of toxic organic compounds. The purpose of bioremediation processes that will an eco-friendly and cost-effective mechanism. The aim is to develop an advanced technique in bioprocesses that will help to minimize toxin risk and thereby acquire new, usable substances. Some of the bioremediation-related compounds like oxidoreductases hydrolases, dioxygenase, peroxidases, and laccase are most widely considered. The aim of the review is to express the role of microbial enzymes on the bioremediation of toxic, hazardous environmental pollutants.
IMPLEMENTASI KONSEP PENTAHELIX DALAM PENGEMBANGAN DESA WISATA CIBUNTU
Authors: Pusparani  , Rianto
Published: August 2022

Cibuntu Village is one of the villages in Kuningan Regency which has various tourist destinations and attractive natural beauty. The success of developing the tourism sector cannot be separated from the synergistic collaboration of various parties. The Ministry of Tourism, through Permen number  14/2016 on Guidelines for Sustainable Tourism Destinations, emphasizes that there is need for optimal interconnection between the business, government, community, academic and media (BGCAM) sectors in building the tourism sector or more commonly known as the Penta Helix Concept so that tourism can provide benefits to society. To see the extent to which the Penta Helix concept has been applied in the development of the Cibuntu tourist village, this research was conducted. This research is a case study, the sources in this research are five peoples  who are representatives of business people, government, community, academics and the media. The results show that the implementation of the Penta helix concept has gone well. The synergic coordination and collaboration of each Penta helix element has led to Cibuntu Tourism Village winning several awards in the tourism sector. The coordination and collaboration that has been built between the government, tourism business actors, communities, academics, and the media need to be maintained.
ANALISIS DAYA TARIK LATTE ART TERHADAP MINAT PEMBELIAN DI COFFE SHOP KOTA BOGOR
Authors: Hidayat Rahmat , Indrawan Theodorus Ezra
Published: August 2022

Coffee as the Coffee Shop's superior product can have added value, one of which is through the expertise and creations of coffee mixters (baristas) who serve coffee with the addition of Latte Art. This study aims to analyze the effect of Latte Art's Attractiveness to Purchase Interest at the Coffee Shop in Bogor City. The number of samples used in this study were 30 respondents at the Coffee Shop in Bogor City. Data was collected using a questionnaire with a non-probability sampling technique and direct observation at the Coffee Shop in Bogor City. Meanwhile, the non-probability sampling technique used in this study was accidental sampling. The research data were analyzed using a statistical application program on a computer, namely the SPSS version 16.0 program. The scientific method used in this research is a descriptive method with a quantitative approach. Data were analyzed using descriptive analysis, Pearson Product Moment correlation coefficient test, Kolmogorov-Smirnov normality test, simple linear regression analysis and partial significance test (t test). Based on the results of simple regression equation analysis, it can be seen that Latte Art Products have a significant effect on Purchase Interest at the Coffee Shop in Bogor City. The results of the t-test indicate that the t-count value is greater than the t-table (3.797 > 2.04841) and the significance value (0.001) is smaller than the 5% significance level. Thus, the Latte Art product is stated to have a significant effect on Purchase Interest at the Coffee Shop in Bogor City and the alternative hypothesis (H1) is accepted.
PENGARUH KETERSEDIAAN GREEN PRODUCT TERHADAP KEPUTUSAN PEMBELIAN PRODUK MERCHANDISE DI STARBUCKS FOOD CENTRUM SUNTER JAKARTA UTARA
Authors: Panggih Stevica , Krisnadi Antonius Rizki
Published: August 2022

Environmental pollution is caused by the lack of human awareness to protect the environment and plastic waste has the highest percentage of waste. Starbucks as a coffee shop spread across many countries plays a role in reducing plastic waste to support the green product movement. This research was aimed to know about the influence of green product indicators. Green product indicator itself consists of (3) items, which consists of green product, green product performance in accordance with consumer expectations, raw materials are not dangerous. The location that was the subject of research is Starbucks Coffee, a coffee shop located in North Jakarta. The fixed sample was 85 respondents, taken by purposive sampling method, which they must be at least 20-60 years-old, and have bought food or drink in Starbucks Coffee Food Centrum.

 The test is results in this study indicate that there are two that give partial influence, namely green product performance and raw materials are not dangerous, while green product has no effect. But when conducted simultaneous testing, all indicators of green product expressed influence the purchase decision at Starbucks Coffee Food Centrum significantly. it means all variables (X1-X3) simultaneously influences consumer’s perceived intention in Starbucks Coffee Food Centrum. Both of those statements can be concluded as the reason of buying in Starbucks Coffee Food Centrum, not just because only one reason, but more than one indicators must be strengthened one another when it’s tested simultaneously.
Dijital ekran uygulama kullanımının spor bilimleri fakültesi öğrencilerinin sportif yetkinliklerine etkisi
Authors: DEMİR Ümit , CENGİZ Cevdet
Published: August 2022

This study aimed to investigate the association of sporting competencies and digital screen usage among students in Sport Sciences faculties. A cross-sectional survey was conducted at three universities in Turkey. A total of 219 students was surveyed in the spring term of 2021 during the COVID pandemic isolation period. In the research, information about both the use of mobile phones and computers as well as social media and digital game applications, which pose a risk of addiction to these devices, was obtained from the participants. They were asked to complete a self-report questionnaire on their demographic characteristics, mobile phone and Personal Computer (PC) usage, and the effect of digital screen usage on their sportive competencies. The results showed that the frequent use of digital screen applications had a negative effect on the students' sporting competencies. There was a significant difference that affected the scores according to gender, PC-ownership, department, daily mobile phone, and social media usage, change in digital screen usage, daily physical activity, and change in daily physical activity.
Konsep Imam Al-Juwaini dalam Maqashid Al-Syari'ah
Authors: Nur Ali
Published: August 2022

Tujuan Utama penelitian ini adalah untuk mengetahui pemikiran imam al-juwaini dalam mengimplementasikan konsep Maqashid Al-syari’ah dalam kehidupan sehari-hari serta mengintegritaskan maqashid syari’ah diperguruan tinggi agama Islam secara umum, khususnya di perguruan tinggiagama Islam Al-hikmah2 benda sirampog brebes.jenis penelitian ini adalah penelitian kajian pustaka atau studi kepustakaan yaitu berisi teori-teori yang relevan dengan masalah-masalah penelitian. Teknik pengumpulan data menggunakan aspek teoritis maupun aspek manfaat praktis. Kesimpulan penelitian adalah mengenai korelasi maqasid syari’ah dengan metode penetapan hukum dalam menginstibatkan hukum Islam.
Effects of Semi-Rigid Connection on Structural Responses
Authors: M.E. Kartal  , H.B. Basaga  , A. Bayraktar  , M. Muvafık
Published: August 2022

There are several idealizations in numerical analysis of structures. In the joints and supports, which is usually assumed to be pinned or rigid, semi-rigid connection should be considered to obtain more realistic, reliable and also economical results. In this study, rotational spring stiffness-connection ratio relation is clearly explained and revealed. A finite element program SEMIFEM is developed in FORTRAN language for the numerical analysis. This program provides to define semi-rigid connections in terms of rotational spring stiffness or connection ratio simultaneously. In the numerical applications, rotational spring stiffness - connection percentage relation of the semi-rigid connected structural members is submitted. Semi-rigid connections are considered in column-to-foundation connection of a portal frame, beam-to-column connection of a prefabricated structure, steel brace connection to reinforced concrete (RC) frame of a steel X-braced RC frame and truss member connection to joint of a steel truss system. The variation of moment, shear force, axial force, displacement and stress is investigated in a selected axis of the structures. Numerical examples are performed with respect to connection percentage of the related structural members by using finite element method. According to finite element analysis results, the degree of the semi-rigid connection is important as much as its existence in the design phase. This study reveals that the effect of semi-rigid connections on structural systems shows different variations from structure to structure.
Performance of the PR connections under combined Axial-tension and moment loading
Authors: A. Pirmoz  , M. M. Ahmadi  , E. Valadi  , V. Farajkhah  , S. R. Balanoji
Published: August 2022

The inherent moment capacity of bolted top-seat angle connections with double web angles (TSDW), categorized as partially restrained (PR) connections according to AISC-LRFD specifications, can be considered in analyses of semi-rigid connections especially when an accurate analysis of such fames is desired. However, in some cases, developed internal forces in the frame elements may affect the connection behavior, considerably. Axial tension force is one of such internal forces that may be imposed on frame connections in some cases such as construction imperfections, seismic loading or under large deflections of the catenary action during the progressive collapse of the semi-rigid frames. This study aims at the effects of the axial tension force on the performance of the bolted TSDW angle connections using nonlinear finite element method (FEM). The obtained results show that the axial tension force reduces the connection moment capacity and stiffness, considerably. Based on the obtained moment-rotation curves, affected by this particular loading type, equations are proposed to estimate the reduction rate of the connection stiffness and moment capacity.
BP-MAC: A High Reliable Backoff Preamble MAC Protocol for Wireless Sensor Networks
Authors: Alexander Klein  , Jirka Klaue  , Josef Schalk
Published: August 2022

Many Media Access Control (MAC) protocols for Wireless Sensor Networks (WSN) use varia-tions of the popular Carrier Sense Multiple Access (CSMA) protocol due to its simplicity and its high perfor-mance in low traffic scenarios. However, CSMA does not always  represent a good choice for WSNs since typical low power transceivers require a significant time to switch between receiving and transmitting and vice versa. Sensor nodes are not able to detect a busy channel during the switching. Thus, the collision proba-bility in WSNs is very high in case of correlated event-driven traffic. In this paper we introduce the BP-MAC protocol that uses a backoff preamble with variable length in order to mitigate the effect of Clear Channel As-sessment (CCA) delay.
Evolution of Concrete Skyscrapers: from Ingalls to Jin mao
Authors: Mir M. Ali
Published: August 2022

This paper has provided a broad overview of different historic developments for concrete high-rise buildings.  The evolution of concrete skyscrapers from the first reinforced concrete high-rise, the Ingalls Building, which was 15 stories high to modern skyscrapers Petronas and the Jin Mao is discussed. How new innovations in construction technology such as the advances in formwork, mixing of concrete, techniques for pumping, and types of admixtures to improve quality have all contributed to the ease of working with concrete in high-rise construction is also briefly discussed in the paper.
Failure Modes of In-filled Frames
Authors: P.G. Asteris  , D.J. Kakaletsis  , C.Z. Chrysostomou  , E.E. Smyrou
Published: August 2022

The main objective of this paper is to present a general classification scheme of the failure modes of in-filled frames, both with and without openings. For the former, the existing classification is summarized based on a literature review. For the latter, recent experimental results on frames in-filled with unreinforced masonry walls with openings and subjected to slowly applied cyclic lateral loads are used, and a number of different failure modes (crack patterns) of masonry in-filled frames are identified and classified into distinct categories. Such a classification of failure modes improves substantially the understanding of the earthquake resistant behaviour of in-filled frames and leads to better methodological approaches regarding their modelling, analysis and design.
Seismic Evaluation of Reinforced Concrete Piers in Low to Moderate Seismic Regions
Authors: A.M. Memari  , H.G. Harris  , A.A Hamid  , A. Scanlon
Published: August 2022

Evaluation of reinforcement detailing with respect to the amount and spacing of transverse reinforcement, development length, and splice length based on seismic provisions for seven Pennsylvania bridges is discussed. The selection of prototype bridges as representative of the stock of all PA bridges for the study are explained. A case study of seismic evaluation of one of the bridges selected based on finite element analysis and ductility estimation is presented as representative of the approach used to evaluate all other selected bridges.
Nonlinear Models of Reinforced and Post-tensioned Concrete Beams
Authors: P. Fanning
Published: August 2022

Commercial finite element software generally includes dedicated numerical models for the nonlinear response of concrete under loading. These models usually include a smeared crack analogy to account for the relatively poor tensile strength of concrete, a plasticity algorithm to facilitate concrete crushing in compression regions and a method of specifying the amount, the distribution and the orientation of any internal reinforcement. The numerical model adopted by ANSYS is discussed in this paper. Appropriate numerical modelling strategies are recommended and comparisons with experimental load-deflection responses are discussed for ordinary reinforced concrete beams and post-tensioned concrete T-beams.
Estimation of Membership Function of Design Variables Using HDMR and FFT
Authors: A. S. Balu  , B. N. Rao
Published: August 2022

This paper presents an inverse reliability analysis to determine the unknown design parameters such that prescribed reliability indices are attained in the presence of mixed uncertain variables. The proposed computational procedure involves the failure probability estimation using High Dimensional Model Representation, transformation technique to obtain the contribution of the fuzzy variables to the convolution integral, convolution using fast Fourier transform, and update of reliability index and most probable point. This is aversatile method that can solve even highly nonlinear problems or the problems with multiple parameters. The methodology  developed is applicable for inverse reliability analysis involving any number of fuzzy variables and random variables with any kind of distribution. The accuracy and efficiency of the proposed method is demonstrated through three examples involving explicit/implicit performance functions.
Safe and Sustainable Tall Buildings: Current Practice and Challenges For the Future
Authors: Mendis Priyan
Published: August 2022

There are currently a number of buildings in excess of 300m under construction in the world and further tall buildings are planned for both residential and commercial markets. The design and construction of tall buildings present many challenges for the design team, from engineers, Architect through to the concrete technologist and the builder. Both safety and sustainability aspects are important in planning and designing tall buildings. Current practice, trends, improvements and some mistakes in designing buildings will be highlighted in this key note address.
Waste Materials in Malaysia for Development of Sustainable Concrete: A Review
Authors: S. P. YAP  , U. J. ALENGARAM  , M. Z. JUMAAT  , K. Y. FOONG
Published: August 2022

This paper discusses on the availability of waste materials in Malaysia and their potential use as building materials in the local construction industry. The waste materials discussed include fly ash (FA), oil palm kernel shell (OPKS), rice husk ash (RHA), palm oil fuel ash (POFA), quarry dust (QD), recycled ceramic, and recycled coarse aggregate (RCA). The past research on the use of these materials shows that structural grade concrete can be produced. . Similarly, the use of FA, RHA and POFA as partial replacement of cement or additional cementitious materials can be used to produce low to medium strength concrete as well as high strength concrete (HSC). In addition, lightweight OPKS enables it in the production of lightweight concrete (LWC). Recent research on the use of FA, RHA and palm oil clinker (POC) to produce geopolymer concrete is also producing results. In general, the utilization of these waste materials in concrete leads to sustainable concrete and reduces environmental impact from the manufacture of concrete using conventional materials such as crushed granite and cement
Retrofit of Unreinforced Masonry Walls Using Geotextile and CFRP
Authors: M.T. Mansourikia  , A. Hoback
Published: August 2022

A preliminary investigation into the suitability of using geotextile as an inexpensive seismic retrofit material was conducted. Ten specimens of unreinforced masonry (URM) walls were constructed with masonry without bars or other transverse reinforcement. One set of two was left unreinforced. The remaining four sets of two specimens were reinforced with either CFRP (laminate) or geotextile. Two widths of reinforcement were created for each reinforcing material. All specimens were tested with cyclical shear loading. The number of cycles before collapse was recorded. Results are compared for geotextile versus laminate. Both materials reduced drift and increased the number of loading cycles before collapse. Even though the laminate increased the number of cycles the most, the geotextile is a more economical solution to retrofitting URM walls therefore warrants further investigation.
Strengthening and Rehabilitation of RC Beams with FRP Overlays under Combined Shear and Torsion
Authors: D. Mostofinejad  , S. B. Talaeitaba
Published: August 2022

This paper deals with evaluating the rehabilitation convenience of a damaged RC beam under the combined shear-torsion effect and retrieving its shear-torsion capacity by using FRP rolled strips. To this end, 9 specimens with 2.85 m lengths and clamped-clamped boundary conditions were made and tested under combined shear and torsion up to fracture (from zero loading eccentricity, corresponding to pure shear, to infinite eccentricity, due to pure torsion). Five of the specimens were ordinary (control) specimens considered as reference and four of them were strengthened with FRP strips from the beginning. Also, four of the ordinary specimens were rehabilitated after fracture by rubbing cement mortar on the cracked faces, then strengthened and tested like other specimens. Results indicated that rehabilitating and strengthening the beam will not only retrieve the initial shear-torsion capacity, but also increase the ultimate capacity up to 60 %. The increased capacity for the specimens strengthened from the beginning was 97%.
Performance of steel beams strengthened with prestressed CFRP laminate
Authors: M.A. Gharib  , W.H. Khushefati  , M.A. Khedr  , E.Y. Sayed-Ahmed
Published: August 2022

Prestressed Carbon Fibre Reinforced Polymer (CFRP) system is generally used for strengthening reinforced concrete beams where CFRP laminate can improve both the strength and serviceability behaviour of reinforced concrete beams via increasing the overall member stiffness. However, the applicability of this technique to strengthening steel structures is still lagging behind its application to concrete structures. In this study, the flexural behaviour of steel I-beams strengthened with prestressed CFRP laminate using a mechanical anchorage system is experimentally investigated. A total of nine steel beams subjected to flexural loading are tested in various conditions to evaluate the effectiveness of the proposed strengthening system. The experimental investigation confirmed that CFRP prestressing increases the ultimate load of the strengthened steel beams and moderately delays the premature debonding failure of the CFRP laminate. Even with low level of CFRP prestressing, significant enhancement in the ultimate load of the strengthened beam was recorded. Beams strengthened using non-prestressed CFRP laminate mainly failed due to premature debonding of the laminate with a slight increase in the failure load. Mechanical end anchorages maintain the CFRP laminate prestress after releasing the jacking force without encountering any debonding of the CFRP laminate till final failure of the strengthened steel beam. The results of the experimental programme and its outcomes are presented and discussed.
Prestress Loss Distributions along Simply Supported Pretensioned Concrete Beams
Authors: J. Kent Hsiao
Published: August 2022

The prestressing forces in prestressed tendons undergo a process of reduction over a period of time. A common assumption is that prestress loss is constantly distributed throughout the span of a simply supported pretensioned concrete beam. The purpose of this work is to investigate the accuracy of this assumption. The types of prestressed concrete beams investigated in this work include the following three typical types of tendon profile: (I) straight strands, (II) single-point depressed, and (III) two-point depressed. The major findings derived from this work are: (1) The total prestress loss is not constantly distributed throughout the span of a simply supported pretensioned concrete beam with any of the three types of tendon profiles, (2) The variation of prestress loss along the span of a pretensioned beam caused by elastic shortening of concrete or creep of concrete is much more significant than that caused by shrinkage of concrete or relaxation of tendons, and (3) The type of tendon profile in a simply supported pretensioned concrete beam has significant effects on the pattern of prestress loss distribution along the beam.
Experimental Study on the Effect of Resin Anchoring Agent Mixing with Steel Grit
Authors: J. Han  , W.J. Xie  , M. Zhang  , H.D. Zhang  , C. Cao
Published: August 2022

To improve the anchorage effect, steel grit or steel shot of different size and different amount were mixed into resin agent commonly used in China coal mine. 19 groups tests were conducted using rightwhorled rebar bolt anchored into steel sleeve. Three bolt specimens were prepared and tested for each group, and as a comparison, the first group of bolt specimens was tested using resin anchoring agent without grit and steel. In the 2-10 groups, steel grits were added with different amount of 30, 40 or 50 and different particle sizes of 1.5, 2.0 and 2.5 mm. Each particle size corresponds to three quantities, a total of 9 groups of tests were conducted. Steel shots were added in 11-19 group tests with different amount and different particle size. The average peak pulling force of the first group is 121.3 (±3.1) kN, 5 of 9 groups of specimens with steel grit are more than 121.3 kN, and 8 of 9 groups of specimens have better average peak pulling force than 121.3 kN. It can be concluded that, under the condition of testing, the anchorage effect can be improved after steel shots are mixed into resin anchoring agent.
Evaluation the Effect of Carbon Nanotube on the Rheological and Mechanical Properties of Bitumen and Hot Mix Asphalt (HMA)
Authors: M Zahedi  , M Barati  , M Zarei
Published: August 2022

The technical characteristics of modified bitumen and asphalt have provided many study opportunities around the world. This article has assessed the effects of adding the Nanomaterial on the rheological specifications of bitumen by adding carbon nanotubes to bitumen and it also has evaluated the physical characteristics and bulk parameters of the surface (Topeka) layer of asphalt concrete sample by conducting Marshall Tests. In this regard, the technical characteristics of bitumen such as penetration grade, softening point, viscosity and thermal sensitivity were tested by adding carbon nanotubes with the amounts of 0.25, 0.50, 1 and 1.5 percent by weight of bitumen. The results show that adding carbon nanotube to the bitumen has been accompanied with a reduction in the penetration grade and an increase in softness of the bitumen, which improves the specifications of bitumen and therefore reduces asphalt tracking at high temperature. Following, the asphalt samples reinforced with carbon nanotubes evaluated for conducting Marshall Test. The results showed that the additive alters the Marshall Test parameters such as increasing the strength and decreasing the flow. Meanwhile, the specific gravity of asphalt mixture was increased and the void space percent of the aggregates was relatively decreased. Moreover, the void space of the asphalt mixture and the void space percent filled with bitumen were relatively increased. Economic analysis was evaluated for a 3-way path. Finally, according to the results and analysis of the Nanomaterial on the Nano specifications of bitumen and asphalt, technically, the results strongly suggest the use of carbon nanotubes. Although economically, the use of carbon nanotubes is limited.
Review of techniques for identifying the chemical composition of Aluminium Composite Cladding cores
Authors: T. Byrnes  , L. Angel  , K. Hunt  , T. Flynn
Published: August 2022

The Grenfell disaster of June 14, 2017 brought into sharp focus the dangers posed by combustible façade materials. Polyethylene core panelling has been implicated in numerous fires such as The Address Downtown, the Saif Belhasa in Dubai and the Lacrosse building in Melbourne. Due to the large number of buildings with potentially combustible cladding, there is significant pressure to find an accurate and fast method to identify such cladding and any associated insulation as part of the overall assessment process. Over the past year, several different approaches to identification have been proposed and in this paper, we recount our expe-riences in developing a methodology to achieve this and discuss the limitations of this method and of competing methods.
Shear Strengthening of RC Beams Using NSM GFRP Bars or CFRP U-Wrap Sheets
Authors: E.Y. Sayed-Ahmed  , M.N. Abou-Zeid  , Helen S. Ghali  , Haidy S. Ghali  , R.M. Armanious
Published: August 2022

Fiber-reinforced polymers (FRPs) have been in view for the past three decades due to their high strength-to-weight ratio and resistance to corrosion. They are widely used as sheets, externally adhered to re-inforced concrete (RC) beams to be strengthened in shear. Although this technique is common, FRP sheets are exposed during their service life to environmental factors. As such, near-surface mounted (NSM) FRP bars may be more favored in shear strengthening of RC beams. Thus, this work experimentally investigates the performance of RC beams strengthened in shear using NSM FRP bars. The experimental results are com-pared to provisions of ACI 440.2-08 for FRP laminates and to design procedures proposed by De Lorenzis and Nanni (2001) and Dias and Barros (2010) for NSM bars. The current investigation reveals that ACI 440.2-08 overestimate the shear capacity of strengthened beams for widely spaced FRP laminate; thus, an up-per limit on the spacing between the sheets should be included in the current provisions. On the other hand, De Lorenzis and Nanni model correctly predicts the capacity of beams strengthened in shear using NSM bar; however, this model still needs a limit on the minimum spacing between the NSM bars.
Survival of Reinforced Concrete Flat Plate System against Column Loss
Authors: Waleed E. El-Demerdash  , Salah El-Din E. El-Metwally  , Mohamed E. El-Zoughiby
Published: August 2022

Column loss in a flat plate building, due to punching shear, explosion, impact load or any acci-dental event, can lead to what is termed progressive collapse. Progressive collapse is inherently a dynamic process, which makes it difficult to experimentally explore structures with real scale. Therefore, this paper aims to numerically investigate the behavior of flat plate systems due to column loss utilizing nonlinear finite element analysis with the aid of the computer software (ABAQUS). In this investigation, the nonlinear dynamic re-sponse of both an old flat plate building, designed according to the ACI 318-71, and a similar modern building, designed according the ACI 318-14, subjected to an instant removal of a column is examined. The obtained results clearly reveal that the old flat plate building without continuous slab bottom reinforcement at columns is highly vulnerable to progressive collapse and the efficiency of the continuous bottom reinforcement within the column strip, as recommended by the ACI 318-14, in preventing the disproportion or progressive collapse of a reinforced concrete flat plate building. Such reinforcement is able to produce alternate load path through the tensile membrane action, thus providing ductility and robustness in the system.
On the Use of a Regular Yield Surface for the Analysis of Unreinforced Masonry Walls
Authors: P.G. Asteris  , A.D. Tzamtzis
Published: August 2022

A complete methodology for the non-linear macroscopic analysis of unreinforced masonry (URM) shear walls under biaxial stress state is presented, using the finite element method. The methodology focuses on the definition / specification of a general anisotropic (orthotropic) failure surface of masonry under biaxial stress, using a cubic tensor polynomial, as well as on the numerical solution of this non-linear problem. The characteristics of the polynomial used, ensure the closed shape of the failure surface which is expressed in a unique mathematical form for all possible combinations of plane stress, making it easier to include it into existing software for the analysis of masonry structures. The validity of the method, using the derived failure surface, is demonstrated by comparing the results from the study of the non-linear behaviour of URM wall panels, under uniform compressive and shear loading, against results derived by other investigators.
Computer Application to Study Engineering Projects at the Early Stages of Development
Authors: M. H. Gedig  , S. F. Stiemer
Published: August 2022

This paper describes a computer software application, the Qualitative Engineering System (QES), which the engineer can use to perform qualitative and semi-quantitative analysis of preliminary engineering designs. In engineering practice, many situations arise in which the engineer wishes to perform a logical, objective comparison between conceptual or preliminary design options. Although there exist many applications which can be used to perform detailed numerical analysis to justify detailed final designs, relatively fewuseful programs are available to validate designs at the preliminary stages. The early stages of design are characterized by higher levels of uncertainty than the latter stages. Established qualitative and semiquantitative reasoning techniques may be used to detail with uncertainty and incomplete information in a sound, logical manner. The QES application utilizes a unified framework, which is used to implement a number of qualitative and semi-quantitative reasoning techniques. This paper gives an explanation of qualitative and semi-quantitative analysis in the context of the QES application. In addition, the paper gives some practical examples of how the QES program can be used in the engineering environment
Experimental & theoretical behavior of thin walled composite filled beams
Authors: M. Khandaker  , Anwar Hossain
Published: August 2022

The behaviour of thin walled composite (TWC) filled beams with normal (NC) and lightweight volcanic pumice concrete (VPC) as in-fill, is described based on comprehensive series of tests. The strength and failure modes of the beams are found to depend on the interface connections. The effect of various modes interface connections are co-related to the generation of shear bond between sheeting and concrete using both experimental and theoretical results. Analytical models for the design of beams are developed and their performance is validated through experimental results using both full and partial connection. Appropriate design recommendations and practical design charts have been developed so that the designer can check whether the strength will be governed by buckling or yielding of steel and be able to design the beam accordingly.
Design of non-linear semi-rigid steel frames with semi-rigid column bases
Authors: S. O. Degertekin  , M. S. Hayalioglu
Published: August 2022

This article presents an analysis and design method for steel frames with semi-rigid connections and semirigid column bases. The analysis takes into account both the non-linear behaviour of beam-to-column connections and P-Δ effects of beam-column members. The Frye and Morris polynomial model is used for modelling of semi-rigid connections. The members are designed according to the specifications of American Institute of Steel Construction (AISC) Allowable Stress Design (ASD). The design process is interactive, andgives choices to the designer, to change member cross-sections and connection parameters for economical and practical reasons, interacting with computer. Two design examples with various type of connections are presented to demonstrate the efficiency of the method. The semi-rigid connection modelling yields more economical solutions than rigid connection modelling.The semi-rigid column base modelling also results in lighter frames. It is also shown that changes in the stiffness of the connections may result in economical solutions and alteration in the sways of the frames
Evaluation of stress distribution in bolted steel angles under tension
Authors: Mohan Gupta  , L. M. Gupta
Published: August 2022

The stress distribution in the vicinity of connections in a bolted steel angle is non-uniform because of the coupled effects of connection eccentricity, shear lag and stress concentrations. Although, some  researchers have attempted finite element analysis, stipulations in various codes and specifications regarding the design of angle tension members are primarily based on the experimental studies. Only a couple of previous studies has included geometric as well as material non-linear effects in such finite element analysis. This paper presents the state-of-the-art review of finite element techniques used in modelling the angle tension members with bolted connections. This review is followed by a non-linear finite element analysis so as to obtain the stress distributions in the vicinity of connections, at design loads. This stress distribution is then evaluated to draw several realistic conclusions.
FE Analysis of Complex Discontinuous and Jointed Structural Systems
Authors: A.D. Tzamtzis  , P.G. Asteris
Published: August 2022

This study presents an efficient finite element analysis technique which shows great versatility in analysing complex discontinuous systems subjected to static, dynamic, or seismic loadings. The method incorporates discontinuities in the analysis of discontinuous structures by the use of interface elements designed to simulate the actual behaviour at the interfaces between contacting materials. Several case-problem studies that exhibit discontinuous behaviour have been performed in order to demonstrate the potential and applicability of the proposed method of analysis. One of these studies is reported in Part 2 of this paper, where a non-linear model for the analysis of unreinforced masonry walls is presented. Response results obtained, demonstrate that the overall response of a discontinuous system to external loading is significantly affected by behaviour at the interfaces between contacting materials. Through the inclusion of discontinuities with particular measurable properties, the proposed method of analysis conforms better to actual conditions than do other methods where a continuum is assumed.
Nonlinear modeling with confidence estimation using Bayesian neural networks
Authors: A.T.C. Goh  , C.G. Chua
Published: August 2022

There is a growing interest in the use of neural networks in civil engineering to model complicated nonlinearity problems. A recent enhancement to the conventional back-propagation neural network algorithm is the adoption of a Bayesian inference procedure that provides good generalization and a statistical approach to deal with data uncertainty. A review of the Bayesian approach for neural network learning is presented. One distinct advantage of this method over the conventional back-propagation method is that the algorithm is able to provide assessments of the confidence associated with the  network’s predictions. Two examples are presented to demonstrate the capabilities of this algorithm. A third example considers the practical application of the Bayesian neural network approach for analyzing the ultimate shear strength of deep beams.
Wind Loading on Tall Buildings
Authors: Mendis Priyan , Ngo Tuan , N. Haritos  , A. Hira  , B. Samali  , J. Cheung
Published: August 2022

Simple quasi-static treatment of wind loading, which is universally applied to design of typical low to medium-rise structures, can be unacceptably conservative for design of very tall buildings. On the other hand such simple treatment can easily lead to erroneous results and under-estimations. More importantly such a simplified treatment for deriving lateral loads does not address key design issues including dynamic response (effects of resonance, acceleration, damping, structural stiffness), interference from otherstructures, wind directionality, and cross wind response, which are all important factors in wind design of tall buildings. This paper provides an outline of advanced levels of wind design, in the context of the Australian Wind Code, and illustrates the exceptional benefits it offers over simplified approaches. Wind tunnel testing, which has the potential benefits of further refinement in deriving design wind loading and its effects on tall buildings, is also emphasized.
Introduction to the Analysis and Design of Offshore Structures– An Overview
Authors: Haritos Nick
Published: August 2022

This paper provides a broad overview of some of the key factors in the analysis and design of offshore structures to be considered by an engineer uninitiated in the field of offshore engineering. Topics covered range from water wave theories, structure-fluid interaction in waves to the prediction of extreme values of response from spectral modeling approaches. The interested reader can then explore these topics in greater detail through a number of key references listed in the text.
Aspects of the Design of Fire-Resistant Plasterboard Walls in Fire
Authors: I. D. Bennetts  , K. M. Moinuddin
Published: August 2022

This paper gives the detailed results of a series of fire tests on plasterboard fire-resistant wall construction where that construction was penetrated by steel elements simulating the presence of penetrating purlins or rafters. The tests were conducted to investigate the temperatures experienced by such penetrating elements on the unexposed side of the wall and within the wall itself. The aim of the experiments was to investigate fire spread due to the temperature rise of penetrating elements and whether protection of such elements on each side of the wall is necessary. The experimental work shows that for practical fire wall construction, typical of which is likely to be found in warehouse construction, the temperatures achieved by the steel members on the unexposed side of the wall are not sufficiently high to cause fire spread. It is concluded that protection of the penetrating roof members is not required. Since fire walls are often used in single storey buildings, where the roof structure is mostly unprotected, it is important to ensure that a fire wall is not damaged by the deforming roof structure and that there is adequate fire-stopping around penetrations to prevent spread of flame through gaps. Measures to achieve these outcomes are considered in this paper.
Plastic Mechanism and Elastic Analyses in the Strength Estimation of an Axially Compressed-Thin-Walled Channel Steel Section Beam
Authors: Harkali Setiyono
Published: August 2022

This paper presents the study of an analytical model to estimate the strength of a thin-walled channel steel section beam subjected to axial-compressive loads. The model is based on two different methods of analysis, which are performed by analysing a plastic failure mechanism and elastic behaviour of the beam. These analytical methods can be used to establish plastic-unloading and elastic-inclining-theoretical load-deflection behaviour of the beam. Meanwhile, the axial-compressive strength of the beam is estimated by directly measuring the value of load at an intersection point between two different curves of the theoretical load-deflection behaviour. The accuracy of using this analytical model is also verified by comparing its estimated data of the strength to the one obtained from a number of tests on 38 specimens of thin-walled channel steel section under the test loads of axial compression. It is clearly shown that deviation of the analytical data from the experimental one is still scattered within acceptable limits of ± 20%. A statistical analysis of the scattered data indicates that its mean value is 1.03 with standard deviation of 0.058. This certainly means that the estimated strength, on average, displaces from the actual one by 3% and mostly tends to be conservative.
Enhancing the performance under close-in detonations with polymer reinforced CRC
Authors: B. Riisgaard  , A.Gupta  , Mendis Priyan , Ngo Tuan
Published: August 2022

Compact Reinforced Composite, CRC, is a high-strength cement-based composite possessing an enormous flexural and energy-absorbing capacity due to close-spaced high strength steel reinforcement and a high-strength cement-based fiber DSP matrix. The material has been used in various construction projects including as protection for explosion hazards. In connection with explosive impact, the fraction of shear reinforcement needed to obtain full flexural capacity is controlled by the stand-off distance. For close-in detonations, a high fraction of shock reinforcement is needed to obtain full flexural capacity without breaching. This paper introducesan efficient method for implementing high fractions of polymer shock reinforcement into a CRC element. Experimental tests and a preliminary finite element analysis were performed to assess the potency of this material.
Typhoons and technical solutions recommended for existing and new houses in the cyclonic regions in Vietnam
Authors: T. Cao Duy  , C. Nguyen Xuan  , M. Nguyen Dai  , H. Nguyen Huu  , C. Bui Tat
Published: August 2022

Typhoons are considered as the most destructive natural disaster in Vietnam. Typhoons that have the intensity scale greater than 10 or 11 (Beaufort scale) cause sever damages to houses and buildings on their paths. Typhoons associated with inundation can also create short- and long-term damages to national socio-economy and have negative impacts on the country’s economic development. The typhoon affected area can be from hundreds to thousands of kilometres depending on the landfall of the typhoon. In Vietnam, the typhoon season is normally from June to October (occasionally to November or December), and is the most intense in September and October. This paper hence provides the information on typhoons in Vietnam. The paper also introduces the technical solutions recommended for existing and new houses located in the tropical cyclonic areas. The technical solutions presented in this paper are based on the Vietnamese traditional constructions, the results of the research projects conducted by IBST and other Vietnamese institutions as well as the international construction experiences regarding to natural disasters prevention and mitigations.