bluuebunny/crossref_metadata_2025 huggingface dataset:
A STUDY ON THE ECONOMIC ANALYSIS FRAMEWORK OF THE ARCTIC ENERGY PLANT CONSTRUCTION PROJECT
Authors: Na Seoungbeom , Jang Woosik , park Jaewan
Published: October 2023

The construction projects in the Arctic region are considered highly uncertain due to the extremely cold construction environment. In this study, we presented an economic analysis framework applying rainbow options that can consider multiple uncertainties. The economic feasibility of oil & gas plant construction projects is mainly affected by fluctuation in oil price and construction cost. Thus, we considered oil price and construction cost fluctuation as main uncertainties. The proposed framework consists of five steps and aimed to be validated through a case study conducted in the Canadian context: (1) estimate construction cost uncertainty (estimate the volatility of construction cost with Monte-Carlo Simulation); (2) estimate oil price uncertainty (estimate the volatility of oil price with geometric Brownian motion); (3) Economic data can be categorized into project data and market data, and detailed data is defined and quantified; (4) the economic feasibility of the project is assessed using the quadrinomial lattice method, which is one of the techniques used to calculate real options; and (5) optimize project decision making. The research findings hold significant meaning as we propose a framework for evaluating the economic feasibility of an energy plant construction project using rainbow options. Furthermore, it is anticipated that the utilization of the proposed framework can enhance the profitability and make a significant contribution to investors planning to embark on energy plant construction projects.
BENEFICIAL IMPACTS OF EMERGING SMART SOLUTIONS FOR ENERGY EFFICIENCY IN THE BUILT ENVIRONMENT
Authors: Oguntona Olusegun Aanuoluwapo , Akinradewo Opeoluwa Israel , Ngobeni Fikile , Aigbavboa Clinton Ohis
Published: October 2023

It is common knowledge that the activities, processes, materials, and technologies employed in the built environment (BE) are excessively energy-intensive. It is also known that the BE is one of the critical sectors of the economy that requires holistic intervention and attention if the global sustainability agenda will be achieved. However, factors such as energy efficiency, water efficiency, waste management, and resource/materials efficiency among others are identified to be key to realizing a sustainable BE. The objective of this study is to identify the benefits of adopting and incorporating Emerging Smart Solutions (ESS) for achieving energy efficiency in the South African BE. The quantitative research method was adopted in this research study. A structured questionnaire was distributed to active construction professionals in the SACI for data collection. Descriptive and exploratory factor analysis was employed to analyze the retrieved data. Findings from the study revealed nineteen benefits of ESS for energy efficiency in their order of importance. The findings further identified reduction in air pollution, carbon footprint reduction, efficient control of energy usage, increased energy security, and market creation for energy-efficient products as the top benefits of adopting ESS. The study conclusively opined that the adoption of ESS will significantly reduce the atmospheric carbon footprint, pollution, and energy cost among others. A robust multi-disciplinary collaboration among stakeholders and political will is recommended to increase the capability of ESS to fulfill its sustainable potential in the BE.
CONSTRUCTION STUDENTS’ PERCEPTIONS OF THE CIRCADIAN RHYTHM
Authors: Rokooei Saeed , Shojaei Alireza , Rokooei Samira
Published: October 2023

Circadian rhythms, as nychthemeron cycles, are a component of the body’s internal clock that regulate essential functions and processes, which are vividly reflected in sleep routines. While issues pertaining to sleeping patterns are general, the problem is underscored among students who may not have established norms due to internal and external motives. Construction students are among those who may even experience worsened situations emanating from the nature of construction jobs. The construction industry is commonly perceived with long working hours, especially for new employees. Therefore, it is crucial to explore the status of construction students’ routines, knowledge, and perceptions about sleep in the context of education and profession. This study aimed to explore how construction students perceive sleeping hygiene and its impacts. This paper addresses the results of the first stage of the study, conducted in 2021-22 in the Department of Building Construction Science at Mississippi State University. A quantitative method was employed to gather the data. The results highlighted students’ experiences and expectations about sleep deprivation and its impact on their performances. The findings of this study contribute to the body of knowledge by emphasizing the importance of sleep effects on construction students’ education and careers.
INDUSTRY SURVEYS REGARDING CONTINUING EDUCATION IN CONSTRUCTION MANAGEMENT
Authors: Minchin Edward , Im Haekyung , Ries Robert , Issa Raymond R. , Asutosh Ashish T.
Published: October 2023

Since perspectives on higher education are continually changing, curriculum must reflect the current needs of industry. However, individual perspectives may differ based on one’s background and social position. The purpose of this study was to strengthen the course content of the master’s programs in Construction Management at the University of Florida. The primary goal of the surveys used was to determine the attitudes of alumni regarding the value of a master’s degree in Construction Management, for themselves, or for those who work for them. Survey questionnaires were developed, and two surveys were conducted on alumni, using Qualtrics Survey software. Two sample tests for equality of proportions were used for statistical analysis. Middle managers and executives shared some common ideas, but they showed different opinions regarding attending the Construction Management School for their Master’s degree. Also, middle managers with a master’s degree tend to find more additional value in students with a master’s degree than middle managers with only a bachelor’s degree. Based on the results, a 16-month Master’s degree program in Construction Leadership was designed, equivalent to four academic semesters.
EXPLORING SCIENTIFIC DOMAIN OF OCCUPANCY ANALYSIS, POE, AND DT IN AECO INDUSTRY: A SCIENTOMETRIC APPROACH
Authors: Pellegrini Laura , Locatelli Mirko , Meschini Silvia , Schievano Marco , Di Giuda Giuseppe Martino
Published: October 2023

Building occupancy patterns strongly influence organizational effectiveness during the operation and maintenance (O&M) phase. Actual occupancy is highly variable over time and differs from the static occupancy levels considered during design phases. Consequently, poor levels of space management, use, and cleanness are detected during the O&M phase, affecting user well-being and satisfaction. Occupancy monitoring and analysis are needed to achieve effective and efficient facility management (FM) and user well-being. The article explores the scientific domains of occupancy detection and analysis, and related main approaches, i.e., post-occupancy evaluations (POEs) and digital twins (DTs) in the architecture, engineering, construction and operation (AECO) industry. A scientometric approach through science mapping and data visualization is applied to analyze 386 bibliographic records from Scopus database. The temporal trend analysis and conceptual structure of the scientific domain are investigated, drawing a picture of the body of knowledge. The performed analysis uncovered the temporal distribution of the publications and the relationships among the topics. DT is a recent topic in the early stages of investigation, while POEs are mature approaches related to sustainability, energy efficiency, productivity, building performance optimization, and user satisfaction. Occupancy detection and analysis are related to FM but less investigated topics in recent years. The research aims to uncover possible research gaps and open challenges in the field for further research aiming to support the optimization of occupancy and space management in the O&M phase, increasing workplace adaptability to changing conditions and needs and user satisfaction and well-being over time.
INFLUENCE OF SOIL FABRIC ON DYNAMIC PROPERTIES OF SAND: AN EXPERIMENTAL STUDY
Authors: Jain Arpit , Mittal Satyendra , Shukla Sanjay Kumar
Published: October 2023

Natural field sites originate under the action of external sources such as rivers, wind, or marine environments. These sources are responsible for constituting a variety of soil fabrics, which ultimately modify the deformation characteristics. Additionally, the dynamic properties of a site present the characterization of a region and have been profusely utilized by field engineers and researchers. In the present study, the dynamic properties of soil specimens have been evaluated for specimen preparation techniques, namely, air pluviation (AP) and water sedimentation (WS). The cyclic triaxial tests were conducted on the strain-controlled consolidated undrained specimens at a frequency of 0.1 Hz. This frequency has been used in several studies to replicate earthquake or liquefaction scenarios. The calculation of shear modulus (G) and damping ratio (D) was performed using symmetric hysteresis loops generated through cyclic loadings. The outcomes suggest that the specimen prepared using the WS technique possesses a larger shear modulus value than AP ones. The reason behind this observation was the lower degradation characteristics of the WS-prepared specimens. Additionally, the liquefaction susceptibility of the specimens has been noticed for different specimens.
DESIGN OF BASAL REINFORCED EMBANKMENTS SUPPORTED BY GEOTHERMAL ENERGY PILES
Authors: Jelušič Primož , Žlender Bojan
Published: October 2023

TThis paper compares the optimal design of embankments reinforced at the base with geosynthetics and supported by geothermal piles and non-geothermal piles using optimization. An optimization model was created to complete this analysis. The model is based on the fabrication cost of the structure, which consists of various materials such as geosynthetics, gravel fill, concrete and steel reinforcement. It was subjected to the limit state and serviceability conditions according to the Eurocode design rules and recommendations for the analysis of conventional and geothermal piles, taking into account geotechnical, structural and settlement constraints. To consider all limit states for embankment along with the piles and geosynthetic, the most important analyses were performed: Stresses in the geosynthetic reinforcement, bearing resistance of the pile, group resistance of the pile, pile group extent, vertical load transfer, lateral sliding, strain/stiffness of the geosynthetic reinforcement, double shear capacity/punching, and the geometric constraints recommended based on the design experience gained from the past project. The optimization model developed in this paper was applied to an example with selected design parameters to demonstrate the usefulness of the optimization model. The results show that the correct determination of the structure geometry, pile dimensions and geosynthetics leads to a significant cost reduction. The construction of geothermal piles for piled embankments support is very economical due to the low vertical load on the piles, if there is a possibility of using energy in the surrounding buildings.
RAILWAY EMBANKMENT CONSTRUCTED ON SOFT DELTAIC DEPOSIT: LONG-TERM BEHAVIOR AND EFFECT OF TREATMENT
Authors: Mallick Joya Rani , Aziz Shamontee , Hoque Iram Lamiya , Maisha Tamanna-E-Hafiz , Haq S.M. Tahsan Ul , Amin AFM Saiful
Published: October 2023

Railway construction over the soft soil of the active Ganges-Brahmaputra floodplain in the Padma Bridge Rail Link is the first of its kind in Bangladesh. A 2D finite element modeling using Plaxis investigated the long-term settlement behavior of ballast bottom as well as the factor of safety (FS) of this railway embankment. The contribution of cement-mixing piles (CMPs) in settlement reduction and FS improvement has been studied. Parametric study considers three train speeds, between 100–170 km/hr, and two soil profiles along different chainages: 82km+183m (Ch1) and 84km+102m (Ch2). The settlement of ballast bottom in both chainages are found higher in the long term, showing greater settlement in Ch2. Due to treatment, the short-term settlement of embankment bottom decreases by 13.8% at lower train speeds, and at 170 km/hr, the reduction increases to 18% and 16% for Ch1 and Ch2, respectively. The long-term settlement of ballast bottom is also reduced by 20% for lower speeds and 22% for a train speed of 170km/hr. CMP treatment is effective in settlement reduction, and the behavior was almost similar for both chainages, both short-and long-term. The treatment is seen to be more effective at higher train speeds. Due to treatment, increases of FS by 29–31% and 25–27% for Ch1, as well as 35–39% and 26–30% for Ch2, are obtained in the short and long term, respectively. The effect of treatment in providing stability is more prominent for Ch2 and its effect is also greater in the short term.
NLP AND SNA FOR UNDERSTANDING RENEGOTIATIONS OF TOLL ROAD PPPs AMID THE COVID-19 PANDEMIC
Authors: Rojas Diego , Guevara Jose , Khallaf Rana , De Marco Alberto , Castelblanco Gabriel , Salazar John
Published: October 2023

The Covid-19 pandemic has directly impacted Public-Private Partnership (PPP) projects worldwide. As a result of these impacts, many of the projects were renegotiated to assure favorable conditions for either the public, private, or both parties. Based on this context, this study seeks to unravel contractual mechanisms implemented or modified within the context of renegotiation processes caused by the Covid-19 pandemic in Colombia’s PPP toll road projects. Thus, this research aims to determine the impacts of the pandemic and the contractual strategies implemented in different renegotiation processes of PPP toll road projects. The mechanisms were analyzed at individual and cluster levels by implementing natural language processing (NLP) and social network analysis (SNA) procedures. These methodologies facilitated the analysis of multiple contractual mechanisms to identify the different impacts and common strategies between renegotiation processes. This research determined the main drivers and strategies to mitigate the effects of the Covid-19 pandemic on Colombia’s PPP projects, providing a methodology to enable contractual and renegotiation analysis. Overall, the renegotiation processes revealed that the pandemic had an economic and time-related impact, with differences between processes based on the renegotiation initiator or project phase at which the process arises.
CAUSES OF CONTRACTUAL DISPUTES IN CONSTRUCTION PROJECTS
Authors: Serpell Alfredo , Torres Ignacio
Published: October 2023

This article reports on the main causes of contractual disputes in Chilean construction projects, a subject not much studied in the country. The research included an extensive review of international literature looking for the main causes of contractual disputes in construction as a reference and framework. Then, a detailed study of 98 dispute arbitrations processes of construction projects was carried out in search of the main causes of disputes. It was found that the main causes of contractual disputes were those related to the category of design and information and that the most frequent cause in general was non-payment or delay in payment. This result is consistent with causes of contractual disputes as reported in international literature. From the 98 arbitrations studied it was possible to establish that the duration of an arbitration was 531 days on average, but that this depends on the cause of termination of the arbitration. It was also observed that the amount requested from the arbitrator by the plaintiff was 80% of the original amount of the contract on average and that the compensation after the sentence was 28% on average of what was initially requested. This information might be useful for companies that anticipate carrying out construction works in Chile and in Latin-American countries to reduce the potential for claims in their works.
FLEXURAL PROPERTIES OF POLYPROPYLENE FIBER REINFORCED CONCRETE CONTAINING FLY ASH FOR NORMAL CONCRETE PAVEMENT
Authors: Sasaki Tsuneji , Higashiyama Hiroshi , Mizukoshi Mutsumi , Fujimori Akinori , Takahara Ryousuke
Published: October 2023

The purpose of this study is to examine the applicability and efficiency of polypropylene fiber reinforced concrete (PPFRC) mixed with fly ash for new concrete pavements. In the field of concrete pavements, many researchers focused on steel fiber reinforced concrete pavements to improve the mechanical properties. Polypropylene fibers can also improve the flexural toughness and the residual flexural strength. However, in the construction sector, a large amount of CO2 is emitted during the production of cement. The reduction of CO2 emissions is an urgent task in the world. The CO2 emissions can be reduced by replacing a part of such cement with fly ash as one alternative material. In this study, four-point flexural tests were carried out on PPFRC with 1.0 vol.% and 1.3 vol.% of polypropylene fiber. Furthermore, the pavement thickness and the reduction of CO2 emissions were calculated based on the test results to examine the effect of added fiber and fly ash replacement. Consequently, the PPFRC pavement reduces the thickness by about 18% and reduces the CO2 emissions by about 30% in comparison with normal concrete pavements.
NUMERICAL MODELING OF HIGH-PERFORMANCE FIBER-REINFORCED CONCRETE SHEAR PANEL
Authors: Piscesa Bambang , Irmawan Mudji , Faimun Faimun , Aji Pujo , Aspar Wimpie Agoeng Noegroho , Purnomo Agus Dwi , Utomo Djoko Prijo
Published: October 2023

High-performance fiber-reinforced concrete (HPFRC) made from engineered cementitious composite can significantly enhance structural performance. The ductility of the structure and the shear load resistance can be enhanced, especially for short-span elements. Improved structural performance can reduce the risk of structural failure during an extreme event of an earthquake. This paper presents numerical modeling of the HPFRC shear panel structure using a multi-surface plasticity model embedded inside an in-house 3D-NLFEA finite element package. The model's parameters were calibrated with the existing test of the HPFRC shear panel. For HPFRC under compression, the peak strain, elastic modulus, and the softening function related to the compressive fracture energy were adjusted. For HPFRC under tension, the strain hardening and crack localization when the HPFRC softens were also proposed. The comparisons were made between the numerical model and the existing test of the HPFRC shear panel. Some conclusions were drawn on the accuracy of the model and its possible application at the structural level.
MECHANICAL AND DURABILITY STUDY ON STEEL AND GLASS FIBERS BASED CEMENTITIOUS COMPOSITE
Authors: Kumar Yogesh , Kumar Sanjeev
Published: October 2023

The study targets the utilization of steel and glass fibers in developing engineered cementitious composite. Compressive strength (CS) tests, split tensile strength (ST) tests, and static flexure tests were conducted to comment on the mechanical behavior of the composites. The durability properties of the designed mixes are commented on using rapid chloride penetration (RCPT) and sulfate tests. The CS of the conventional mix C-40 is compared with the S-ECC and G-ECC. The tested G-ECC specimens were more ductile than the S-ECC specimens and their respective variants. The S-ECC produced better results for both the CS and ST tests than the S-ECC and its variants. The conventional mixes of C-40 resulted in high penetration values than the composites prepared with steel and glass fiber inclusion. The destruction of the aluminosilicate skeleton, which leads to the liberation of silicic acid and sodium ions, is responsible for the deterioration caused during sulfate attack tests.
NALYSIS OF SOLDIER ANT MOUND FOR CONCRETE APPLICATION
Authors: Adetukasi Adesola Olayinka , Fadugba Olaolu George , Alaka Hafiz Alabi , Mahachi Jeffrey
Published: October 2023

This work investigates the effect of partial replacement of cement with uncalcined Soldier Ant Mound (SAM) in concrete. The crystal structures of uncalcined SAM were determined using X-ray diffraction, while the microstructure was characterized via scanning electron microscopy. Fourier transform infra-red spectroscopy was used to analyse the composition and identify specific functional groups. Fresh properties and mechanical properties of uncalcined SAM concrete at different water-cement ratios were investigated. The compressive strength of uncalcined Soldier Ant Mound Concrete (SAMC) was reduced compared to the reference concrete, although not significantly at early ages (up to 21 days). After 120 days of curing, the 5% and 10% SAMC recorded a 10.59% and 20.22% reduction respectively, in compressive strength compared to the reference concrete. The 5% replacement level of uncalcined SAM is recommended for concrete use as it improves workability, the loss in compressive strength is minimal and its concrete shrinks just as the conventional concrete.
TREATED SEA COMPONENTS CONCRETE
Authors: Nassef Ahmad
Published: October 2023

This paper has introduced the concept of sustainable concrete. To save pure water and sand quarries, both seawater and sea sand have been used in concrete mix instead of pure water and normal sand. In addition, the cement has been partially replaced by ash from palm tree wastes to address the effect of salinity on the mechanical properties of the concrete. The workability and compressive strength of concrete were investigated for various percentages of replacement of sea-sand and palm tree waste ash. The slump and compression tests were completed, with the concrete compression test completed after 7 days and 28 days of curing with seawater. The results showed that replacing 30% of the normal sand with sea-sand and 5% of the cement with palm ash wastes in the presence of seawater as a full replacement of the tap water increased the compressive strength by 48.5% when compared to normal concrete with sea water as a mixing water.
THE BEE CONCEPT IN THE PUBLIC PROCUREMENT SYSTEM: THE PERSPECTIVE OF CONSTRUCTION PROFESSIONALS
Authors: Amoah Christopher
Published: October 2023

South Africa's government introduced the BEE policy to help disadvantaged individuals participate in economic activities. This study examined the perceptions of construction professionals concerning the BEE policy. The study adopted a qualitative research approach. As a result of COVID-19 restrictions, the interview questions were emailed to 35 black construction professionals randomly selected, of which 20 were received. Data were analyzed using qualitative content analysis. The findings show that although participants believed the policy had achieved some success since its implementation, there are still challenges hindering the attainment of the project objectives. Some of the positive aspects of the policy are that it has helped previously disadvantaged individuals, increased opportunity for local companies and improved fairness in the procurement systems. The challenges of the policy were identified as restricting the participation of experienced and foreign construction firms in the public procurement process. Again, the policy must be strictly enforced to sustain and achieve the desired outcome. The government must ensure strict adherence to the policy implementation to benefit the intended people to realize the policy objectives. Measures should be put in place to ensure the sustainability of the policy. The study reveals the perceptions of the policy beneficiaries in the construction sector, which may guide the policy implementers on areas of improvement to achieve the policy objectives.
METHODS FOR ACCOUNTING FOR RISKS IN LONG-TERM PROJECTS
Authors: Gamaleldin Amr , Khallaf Rana
Published: October 2023

Risks represent a large portion of a project’s success. This is especially important in long-term projects such as public-private partnerships (PPPs) due to their complicated nature and long duration. Risks manifest in these projects throughout the project phases and can have severe effects on them. Previous literature has studied and reported on various methods for incorporating risks long-term projects; however, there is no universal method used. Hence, this paper identifies and reviews the most commonly used methods. Four methods were identified, which are risk adjusted discount rate, uncertain parameters method, certainty equivalent method, and decoupled net present value (NPV) method. These methods were discussed and contrasted in order to show their uses for long-term projects such as PPPs. The first method was found to incorporate both risk and time in a combined method while the other methods relied on decoupling of the risk and time due to their different natures.
IDENTIFICATION OF DEFECTIVE CONSTRUCTION WORKS DURING BUILDING INSPECTIONS
Authors: Tekin Hamdi , Yılmaz İsmail Cengiz , Koç Kerim , Atabay Şenay , Gürgün Aslı Pelin
Published: October 2023

Meeting the quality requirements in construction works is critical for structural safety of the buildings, particularly in seismically active regions with old building stocks. Code compliance through strict inspections is essential not only for reliable structures, but also for prevention of cost and time overruns causing financial losses. In Turkey, building inspections are mandatory during the construction phase of the projects and building inspectors are responsible from the inspection of the construction works to ensure code compliance. Building inspectors are frequently subjected to different type of problems due several defects during inspections. This study aims to identify the frequently encountered defective construction works based on a quantitative study. A questionnaire was administered to 57 building inspectors by using 1-5 Likert scale to evaluate 20 critical construction work items. The results, which were ranked according to the Relative Importance Index (RII) showed that concrete works, reinforcement works, and HVAC are the top three works where problems were frequently observed during inspections. On the other hand, less problems were observed in painting, landscaping works and prefabricated construction works.
ANALYSIS OF FREQUENCY CONTENT AND STATISTICAL RELATIONSHIP AMONG EARTHQUAKE PARAMETERS OF SEISMIC DATA
Authors: Murshed Rafid Umayer , Zakaria Md. Anu , Noshin Kazi , Uddin Md. Forkan , Ali Mohammed Eunus , AMIN AFM Saiful
Published: October 2023

The frequency content of the strong-motion seismic data collected from seismic stations by the Bangladesh Meteorological Department (BMD) using GL-S60/120 broadband seismometers of earthquakes in and around Bangladesh is examined. In addition, the statistical relationships among various earthquake parameters, such as the peak ground velocity (PGV), magnitude, epicentral distance, and time of arrival of p-and s-waves of the collected data, are analyzed. Approximate seismic wave velocities are also obtained. The Fourier and wavelet analysis results reveal delicate differences in the frequency content of the p-and s-waves occurring during earthquakes. These results are compared to those generated from the STEAD dataset, which contains seismic waveforms collected in the U.S., France, and Greece regions. Regression analysis on the BMD data derives relationships among the aforementioned parameters. Collected data from some stations show perfect linear relationships among PGV and the travel time of seismic waves with magnitude and epicentral distance, whereas, in other stations, such relationships are not significant. Plausible explanations for these disparities are provided along with similar regression analysis using the STEAD data. The findings are useful for earthquake early-warning systems, geology research, seismic risk zone delineation, and seismic hazard forecasts.
SPECIFIC BENDING STIFFNESS COMPARISON OF SPHERICALLY VOIDED BIAXIAL CONCRETE SLABS AND SOLID SLABS
Authors: Urgessa Girum , Haghighi Homa
Published: October 2023

Spherically hollow or voided biaxial concrete slab (SVBS) configurations that implement empty composite balls as a filling material are gaining momentum due to the reduction in mass-to-capacity and mass-to-stiffness fractions. The SVBS configuration depends on taking out the ineffective concrete mass near the mid-section of a floor in which bending stress is less. This will in turn dramatically reduce the overall structural dead weight. This paper presents comparison of normalized bending stiffnesses for a representative spherically voided biaxial concrete slab with its counterpart solid slab. A representative SVBS element is chosen for capturing the volume action (RVE). The RVE is the primary sub-unit that is periodic and it is modeled in finite element software to determine the stiffness values noting that the SVBS is macroscopically similar, elastic in the linear range, and exhibits isotropic behavior transversely with no thermal stresses. An example SVBS system is shown to be more efficient with 16% higher normalized (specific) stiffness values when compared to solid slabs of equal thicknesses.
CRACK OBSERVATION OF RC-WALL EXPERIMENTS USING IMAGE MEASUREMENT
Authors: Yang Yuan-Sen , Hwang Shyh-Jiann
Published: October 2023

This paper presents the image-based measurement for a set of reinforced concrete (RC) wall experiments. The experiments were carried out at the multi-axial testing system (MATS) in National Center for Research on Earthquake Engineering (NCREE) in Taipei, Taiwan. Four specimens of RC walls with different aspect ratios, tie spacing, axial forces were subjected to displacement controlled cyclic loadings. Image measurement were employed to estimate the major displacements, deformations, and crack distributions. The measurement verifies the crack development and the failure mechanisms at different specimens. In addition to the measurement results of the experiments, this paper introduces the procedures of the image-based measurement, as well as the software tools developed in this work. The measurement procedures include camera calibration, image tracking of major points on the specimens, three-dimensional triangulation, image projection and rectification, deformation analysis, and crack analysis. The crack pattern and their opening widths of several selected time points during the experiment are briefly displayed.
EFFECT OF PARTIAL GEO-GRID CONFINEMENT ON REINFORCED CIRCULAR SHORT COLUMNS UNDER AXIAL LOADING
Authors: Singh Pavitar , Roy A.B. Danie
Published: October 2023

Research has been carried out on the feasibility of geogrids in concrete columns. The conventional way of confining via steel stirrups in circular columns was replaced with an alternative technique, geogrids being used as partially confining material along with steel stirrups. The reasons that have inspired such experimental research include that geo-grid encourage flexibility, are easy to handle (lighter in weight) and are economical compared to steel. A total of sixteen columns were cast that varied in terms of spacing of steel stirrups, type of concrete and geogrids used. The columns were subjected to axial load, their load-deformation curves were obtained, and parameters such as ultimate load, maximum axial deformation, secant stiffness, ductility and energy dissipation were evaluated and compared to the control specimen. The test results revealed that the application of geogrids having high tensile strength along with steel fibers showed comparable results for the strength parameters of columns, thus paving out the possibility of reinforcing columns in combination with geogrids and steel fibers.
DESIGN OF POLYNOMIAL FRICTION PENDULUM ISOLATOR CONSIDERING MULTIPLE PERFORMANCE OBJECTIVES
Authors: Lu Lyan-Ywan , Ramadhanti Natalia Nur
Published: October 2023

Previous studies have revealed that sliding isolators with variable curvature (SIVCs) possess better isolation performance than that of conventional isolators, because of their variable mechanical property. However, their applications are hindered by the lack of a systematic design method. To accelerate the implementation of the advanced SIVC technology, this paper proposes a performance-based design method for one type of SIVCs called the polynomial friction pendulum isolator (PFPI). The proposed method that consists of a linear and a nonlinear design stages is able to satisfy multiple performance objectives under dual earthquake levels. In the linear stage, the linearized isolator parameters that comply with design code in the DBE and MCE levels are determined, while in nonlinear stage, the PFPI parameters are determined based on the linearized parameters. Finally, the feasibility of the proposed design method is verified by the dynamic responses of a hysteretic building model with the designed PFPIs
OPTICAL DYNAMIC DISPLACEMENT MEASUREMENT OF SPECIMEN FOR SHAKING TABLE TEST UTILIZING DRONE
Authors: Maida Yusuke , Saito Takasuke , Kishimoto Koki , Miyauchi Hiroyuki , Kusunoki Koichi , Sakata Hiroyasu
Published: October 2023

In recent years, the use of drones for building inspection has been studied in the architectural field. The effectiveness of utilizing drones for building investigation has been previously reported. Drones are also considered effective for building damage investigation in the event of a disaster. However, there are few examples of actual investigations using drones. If drones can be used to assess the damage to buildings affected by earthquakes, damage investigation could be faster, and efficiency and safety could be improved. In this study, the optical dynamic displacement measurements were obtained for the shaking table test utilizing a drone to verify the effectiveness of building measurement at the time of an earthquake. If the drone was not able to remain stationary in air, there was a difference in the value measured by the drone and that by the displacement meter. When the drone was able to remain stationary in air and the disturbance was minimal, the dynamic displacement of the specimen could be measured well. The blur caused by the movement of the drone needs to be addressed in the future to more accurately measure the dynamic displacements of buildings.
EFFECTS OF ROOF SHAPES ON WIND PRESSURE DISTRIBUTION OF MULTI-SPAN LOW-RISE BUILDINGS
Authors: Sharma Deepak , Raj Ritu , Pal Shilpa
Published: October 2023

The present study demonstrates the numerical investigation to find out the effects of roof shapes on the wind pressure distribution of multi-span low-rise buildings. Most of the wind load standards of various nations are provided with wind load information of isolated low-rise buildings which in turn practically came out to be inapplicable during the designing of low-rise buildings with multi-spans. Also, most of the wind load studies are carried out using boundary layer wind tunnel (BWLT) which is sometimes not available, time taking process, and is expensive. Therefore, in the present research, numerical simulation has been done for the model of a low-rise building. For investigation, the Ansys CFX platform has been used with the k-ε turbulence model for different angles of wind incidence at an interval of 15°. The wind pressure distribution has been investigated for the model low-rise building with a rectangular plan having six spans of different roof forms i.e., cylindrical roof, mono-slope roof, hip roof, and dome roof. The outcomes of the present numerical investigations are presented in the contour plots of wind pressure and coefficients of wind-induced pressure on the different roof forms of low-rise buildings. The outcomes of the study will be so much beneficial to structural design engineers while considering the wind loads calculations on the different roof forms for low-rise buildings.
SUGGESTIONS FOR IMPROVEMENTS IN TIMBER PORTAL FRAME DESIGN WITH SEMI-RIGID KNEE JOINTS
Authors: Ozola Lilita , Fabriciuss Janis
Published: October 2023

Timber portal frames assembled on the construction site are the most suitable solution from the point of view of limitations of transportation options. However, the connections of the rafters and columns assembled at the construction site in the knee joints, using bolts, show a certain tendency to show plastic deformations under load. In addition, the transmitted shear forces at the knee joint form different angles with the fiber direction in the rafter and column elements. Service experience of timber portal frames shows that the vertical displacement of the apex point increases, also cracks appear in the rafter elements near the knee joints over time. Unfortunately, code design formats do not present specifications for timber structures incorporating L-shape joints with mechanical fasteners. This article presents the results of studies that confirm the need to supplement the design rules for wooden portal frames. It is recommended to implement the rotational spring constant when define rigidity of L-shape joints for RFEM model of structure. The Hoffman failure criterion has been chosen as the most appropriate of the known ones for evaluating the crack resistance of structural wooden elements, because this criterion includes more important specific properties affecting the development of plastic deformations and the formation of cracks in wood.
ANALYSIS OF MULTISTORY HIGH-RISE BUILDINGS IN HIGH SEISMIC ZONE
Authors: HUSSAIN SADDAM , MOIZ SHIFA , BEDON CHIARA
Published: October 2023

The effects of severe earthquakes on structures are often catastrophic, and thus it is important to consider them. It is especially the case of High Rise Buildings, where the seismic analysis plays a vital part in the structural analysis and in predicting the response of these structures under the seismic loads. The main aim of the optimal seismic design is to withstand seismic loads or at least behave predictably. Also, it allows for minimizing the loss of human lives and damage to infrastructures. In this paper, the attention is focused on the seismic zones of Japan. The study reveals the structural members and their load transfer mechanisms, the types of loads, and the corresponding behavior. The simplified manual calculations for the design of the structural members are presented and compared with more refined results obtained by using the software such as ETABS for the design of the super-and sub-structures.
EVALUATION OF RETROFIT EFFECTIVENESS AND COST IMPLICATIONS OF MRF STRUCTURES USING DISTINCT FRCM COMPOSITE SYSTEMS
Authors: Joseph Roshen , Mwafy Aman , Alam Shahria
Published: October 2023

This paper summarizes the results of a numerical investigation to assess the effectiveness of retrofitting pre-seismic code concrete framing structural systems using two distinct fiber-reinforced cementitious matrix (FRCM) composites. While FRCM composites were focused in the literature at the member level, this study focuses on implementing this retrofit technique effectively at the structure level. Several static pushover analyses (SPAs) and inelastic dynamic simulations (IDSs) are carried out for FRCM-retrofitted RC frames representing the lateral force-resisting system of a moment-resisting frame (MRF) structure. Correlating the numerical simulation results and experimental results obtained from another study verified the selected fiber discretized section modeling technique for FRCM retrofitted MRFs and reflected the effectiveness of the adopted approach in prolonging local and global damage states. The verified modeling technique of the risk-mitigation measure is then employed to evaluate the performance of an upgraded RC building using three-dimensional fiber-based numerical models. Finally, a parametric study using SPAs and IDSs using multiple seismic scenarios is conducted to select the most effective FRCM retrofit material for the seismic performance enhancement of the benchmark structure. The study concludes that using the selected FRCM retrofit technique effectively mitigated the structural collapse damage state of the substandard building at the design and maximum considered seismic intensity levels by 28% and 32%, respectively.
PERFORMANCE EVALUATION OF BEAMS STRENGTHENED WITH MECHANICALLY ANCHORED CARBON FIBER-REINFORCED CEMENTITIOUS MATRIX (FRCM)
Authors: Holsamudrkar Nikhil , Banerjee Sauvik , Tewari Asim
Published: October 2023

Textile reinforced mortar (TRM), more popularly known as fiber-reinforced cementitious mortar (FRCM), has unique characteristics such as an excellent bond with the concrete substrate, applicability in a wet environment, and resistance to high temperatures. It is now considered a substitute for the fiber-reinforced polymer (FRP) due to the vast progress in FRCM and the increasing complexity of FRP-concrete or FRP-masonry debonding. Strengthening beams with FRCM can be implemented using direct wet layup, Near-surface mounted (NSM), etc. Observed failure modes in the literature show fiber-fiber slip and fiber-matrix debonding as dominant modes. Some authors also studied mechanical anchorages to improve these interfacial limitations. Anchorage in FRCM includes adding transverse layers at the end and intermediate locations, winding the fabric around the bar, and embedding it into the substrate or fan-type anchorage as used in FRP. The present study, 12 beams were strengthened using an indigenously developed unidirectional carbon FRCM system with anchorage. The study parameters include the number of layers and strengthening strategies such as mechanical anchoring and pressure impregnation. For the study, a novel yarn-based mechanical anchorage is developed suitable for Indian site conditions. It is found that the developed mechanical anchorage strategy improves the ultimate load-carrying capacity of the beam by about 16% compared to conventional cement-matrix impregnation. Fiber-rupture failure was observed for anchored specimens, whereas fiber-fiber slip was observed for impregnated specimens.
SEISMIC VULNERABILITY ASSESSMENT OF BASE-ISOLATED RC FRAME BUILDING USING DDBD METHOD
Authors: Jain Ritika , Gondaliya Kaushik , Palsanawala Twinsy , Vasanwala Sandeep , Bhaiya Vishisht
Published: October 2023

The direct displacement-based design (DDBD) method is widely used worldwide because it allows structures to be designed based on their expected performance criteria. The DDBD approach is utilized so that base-isolated building structures can meet the seismic performance parameters established by the displacement threshold. In the present study, an 8-story, 10-story and 12-storey base-isolated RC frame building is designed using the latest Indian seismic standards, with lead rubber bearing (LRB) as the base-isolation system. Force-based and DDBD methodology is implemented and compared for the selected base-isolated RC frame buildings. The nonlinear time-history analysis is conducted to evaluate the nonlinear lateral response of the RC frame buildings. The results indicated that the traditional force-based method shows almost 12% less top-storey displacement than the DDBD approach. The DDBD approach provides enhanced reliability, simplicity, and convenience in seismic design for base-isolated building frames with LRBs, making the observations more dependable and easier to employ.
INVENTION OF FLOATING GATES BASED ON ARTIFICIAL INTELLIGENCE DESIGING FOR MARED DAM AND WATERWAY
Authors: Turk Afshin , Mombeni Bahram , Ghanavatizadeh SHabnam
Published: October 2023

The Karun River is oriented from Zagros Mountains. In the MARED pump station, flat dam and waterway should be constructed to prohibit the intrusion of Persian Gulf tide waves. First layout belonged to SWECO consulting engineering in 1975 that were decided to build ship lock and dam by cubic concrete boxes as the main structure. Dam bed should be stabled to pass barges through waterway (500 tons capacity) and concrete piles ($30ˏ000ˏ000 in 2010). Second scheme of dam and waterway were designed to make with steel pipe piles, steel gates, concrete walls and embankment at 2018 more than $100ˏ000ˏ000 cost. Invention design could be replaced in the MARED dam and waterway. Floating steel gates must be rotated vertically by AI Designing. Steel gates shall be designed to add air inside the gate body. Movable gates are simulated through the fish swim bladder to operate the system that can be adapt with the water fluctuation. Air could be inserted into the simulated swim bladder by the compressor to buoy the gates. Also, it can be discharge the air automatically when the water level needs to be down. The effective depth is more than +18m therefore floating gates should be made by the hollow steel box. The total cost of the third scenarios may be estimated less than $10ˏ000ˏ000 for AID at 2023. Main dam was made to reduce costs using the pipes piles and buoyancy gates. Sediment flow can easily pass through the dam bottom and monitoring floating gates.
DAMAGE DETECTION IN A STEEL BEAM USING VIBRATION RESPONSE
Authors: Islam AKM Anwarul , Sharma Utshree
Published: October 2023

Changes in vibration signals, natural frequency and modal parameters were used for damage detection in a steel beam. Several tests were performed on simply supported steel beams having open transverse cracks with varying depths and locations. Frequencies for the first three vibration modes were generated from the analytical, numerical, and experimental models. Analytical frequencies were calculated assuming Euler-Bernoulli beam and solving partial differential equations. Vibration signals were collected using a portable digital vibrometer and analyzed through Fast Fourier Transform. The finite element beam models were calibrated using experimental results. The graphical plots of the normalized frequency from the experimental study and FE models showed similar pattern for the first mode. The nodal points were identified as the locations where the damaged frequency equals the frequency of an intact beam. The existence of damage in the beam specimen was confirmed by comparing the natural frequency of a beam at its intact and damaged states. Equations relating normalized frequency with varying crack depth and location were proposed.
EFFECTS OF NEAR-FAULT ON DYNAMIC RESPONSE OF A STRUCTURE EXCITED BY EARTHQUAKE WAVES
Authors: Hayir Abdul , Inatci Rohat
Published: October 2023

The goal of this study is to concentrate on the near-fault effects on the structure behavior of underground excitation. To figure out the exact behavior of the structure, a simple model is chosen. During the solution process, dynamic soil-structure interaction is taken into account. The physics of the problem is very complicated owing to the reflection of the waves from the free surface and fault boundary, and the scattering of the waves from the foundation and transmission of the energy into the structure. The materials of the soil and the structure are considered as homogeneous and isotropic, and the foundation is assumed as a rigid body. Response of the structure in the frequency domain is derived using Wave Function Expansion Method and Image Method. Numerical results show that when the structure approaches the fault, the amplitudes of the foundation and relative displacements of the structure are getting bigger. The incident angles of the waves have a big influence on the response of the structure close to the fault, therefore the standard design code should not be applied in the analysis of the structures. It is concluded that near-fault effects should be considered carefully.