bluuebunny/crossref_metadata_2025 huggingface dataset:
PRIORITIZATION OF PIPELINE REPLACEMENT BASED ON FAILURE RATE
Authors: Singh Amarjit , Song Xi
Published: March 2020

The purpose of this paper is to prioritize water pipelines for replacement through the analysis of pipeline failure rates and reliability. By using actual pipe condition record data from Honolulu Board of Water Supply (BWS), the constant failure rate is recognized through Bathtub profile and used to calculate reliability. This paper provides the utility manager a quantitative method to evaluate and arrange pipeline renewal. It assists in determining maintenance schedules depending on the age and type of the pipe by plotting the corresponding failure rate against time. Reliability helps determine whether a certain group of pipes are within the acceptable practice threshold to signal replacement. In this paper, the analysis of four major types of pipe systems from BWS are conducted. With the data from fiscal year (FY) 2008, the failure rates are calculated, and the reliability of all pipelines are seen to be above 80%.
PROJECT PERFORMANCE INDEX FOR CAPITAL INTENSIVE CONSTRUCTION PROJECTS
Authors: Syed Shoeb , Elwakil Emad
Published: March 2020

Holistic construction performance measure has been an elusive and highly sought-after goal. The stochastic nature of construction processes and the number of stakeholders involved in these processes have added to the complexity of the problem. Large-scale infrastructure projects produce big data in form of actual site parameters, safety data, risk analysis data, cost data, financial data, quality assurance data and procurement data. This research aims at developing a project performance index. The factors influencing project performance have been grouped together as Critical Success Factors (CSFs) then through survey and expert opinions, relative weights have been collected for these factors. The factors and weights have been modeled through Regression Technique and validated through analytical and mathematical methods. The developed index will benefit the academic researchers and industry practitioners to assess the performance of the project and to increase the efficiency of project performance.
AN ENGINEERING RELIABILITY ANALYSIS METHOD BASED ON ADAPTIVE METAMODELS
Authors: Wang Qian , Jarosch Erica , Fang Hongbing
Published: March 2020

In practical engineering problems, numerical analyses using the finite element (FE) method or other methods are generally required to evaluate system responses including stresses and deformations. For problems involving expensive FE analyses, it is not efficient or straightforward to directly apply conventional sampling-based or gradient-based reliability analysis approaches. To reduce computational efforts, it is useful to develop efficient and accurate metamodeling techniques to replace the original FE analyses. In this work, an adaptive metamodeling technique and a First-Order Reliability Method (FORM) were integrated. In each adaptive iteration, a compactly supported radial basis function (RBF) was adopted and a metamodel was created to explicitly express a performance function. An alternate FORM was implemented to calculate reliability index of the current iteration. Based on the design point, additional samples were generated and added to the existing sample points to re-generate the metamodel. The accuracy of the RBF metamodel could be improved in the neighborhood of the design point at each iteration. This procedure continued until the convergence of the reliability analysis results was achieved. A numerical example was studied. The proposed adaptive approach worked well and reliability analysis results were found with a reasonable number of iterations.
QUANTIFYING THE IMPACT OF CONGESTION ON CONSTRUCTION LABOR PRODUCTIVITY USING AGENT-BASED MODELING
Authors: Rahal Mohammad , Khoury Hiam
Published: March 2020

Several findings from the construction field stipulate that productivity falloffs are primarily management-related; however, this notion does not consider the direct impact of these same management decisions on the workers themselves. For instance, the planning of the workspace layout delves in a spatial configuration which if not properly managed can potentially result in congestion that, in turn, directly affects labor productivity. Previous research efforts developed models to analyze the effect of congestion on labor productivity but failed to capture all the complexities of this mechanism and its dynamics. Therefore, this paper puts forward the groundwork of an agent-based simulation model (ABM) and presents work targeted at quantifying the impact of congestion on the productivity of construction crews. More specifically, the ABM model takes into account two construction trades working in the same area and tackles five scenarios each depicting different congestion and interaction levels. At the heart of this simulation is a quantitative model that defines essential congestion metrics and outputs space interference values. Experiments were conducted and results highlighted that the higher the space interference values the less productive the crews become. Additionally, these values will constitute an integral part in future work when studying the impact of congestion on the crews' learning curve, whereby the latter being a major gauge for levels of productivity.
QUANTITY UNCERTAINTIES IN REINFORCEMENT WORKS-COMPARISON OF PUBLIC VERSUS PRIVATE CLIENTS
Authors: Kummer Markus
Published: March 2020

Uncertainties are systematically considered and dealt with by applying probabilistic calculation methods, such as Monte Carlo simulations. When selecting appropriate distribution functions for input parameters, users are constantly faced with the issue of having to choose the "right" distribution function for the relevant parameter. Quantities of individual works play a crucial role for costing and pricing, but also for construction process and logistics planning purposes. Quantities stated by the client in its structural specifications are fraught with uncertainties owing to, for instance, incomplete plans at the time of specification, inaccurate calculations, or mere estimates. This is why actual quantities can either be greater or smaller than the specified quantities. This paper demonstrates how distribution functions can be derived from expert surveys delivering responses from actual construction practice. Specific reference is made to reinforcement works whilst distinguishing between public and private clients. The outcomes of the survey presented and discussed in this paper include descriptive data analyses as well as violin plots and fitted distribution functions.
REACTIVE DEVALUATION AS A BARRIER AGAINST AMICABLE CONSTRUCTION DISPUTE SETTLEMENT
Authors: Li Keyao , Chow On Yi , Cheung Sai On
Published: March 2020

Disputes are common in construction projects. Protracted unresolved dispute destroys contracting parties' desire to fulfil the project objectives. In this regard, promoting amicable and efficient construction project dispute resolution (CPDR) has been one of the key recommendations of almost every construction industry review. However, disputants' irrational behaviors would derail trajectory to settlement. Notable example of irrational decision is failing to seize settlement option that provides utility to both disputing parties. This can be the result of a deep-rooted psychological barrier called reactive devaluation (RD). RD describes the behavior of habitually devaluing the proposal raised by the counterpart. Disputants would reject a proposal irrespective of the quality and reasonableness of the proposal, just because it is raised by the counterpart. The occurrence of RD in CPDR would block proposal exchanges that are inevitable if a settlement is to be reached. This study aims to examine the application of RD in CPDR. Possible manifestations of RD in CPDR scenario were summarized and a conceptual framework of RD was proposed. Five types of RD were identified: reluctance to change, doubts about counterpart's ability, overconfidence, biased information processing, and mistrust of the counterpart. Furthermore, suggestions to alleviate RD were also discussed.
REDUCTION OF CO2 EMISSIONS IN CEMENT PRODUCTION BY USING PREHEATER
Authors: Xie Haiyan , Solanki Pranshoo , Mojadam Alireza , Liu Wenfang
Published: March 2020

Cement has a pivotal role in the construction industry. However, cement is one of the key contributors to global CO2 emission levels. This is due to the energy-intensive nature of cement production processes. This comparative-descriptive study focuses on the potential factors to reduce the CO2 emission level in cement production and the decision-making process of adopting new environmental-friendly technology in production. Particularly, this study compares alternative technologies in cement manufacturing to reduce CO2 emission. It collects both the industry data and the data from Texas, which is the biggest contributor to CO2 emission in the US, to analyze how a shift in production technology could affect CO2 emission and eventually improve the outcomes of environment protection and energy efficiency. This paper projects a possible improvement of implementing the method of preheater-precalciner in cement production in lieu of wet and long-dry process to upgrade kilns and reduce problematic CO2 emission. This study suggests shifting from wet and dry kilns to preheater-precalciner systems to obtain the potential benefits of CO2 emission reduction in the cement industry.
RESEARCH ON WIND PERFORMANCE AND FIELD EXPERIMENT OF LARGE SCALE COMPLEX SURFACE SPACE TRUSS WITH STEEL PIPE
Authors: Wang Xiuli , Ran Yonghong , Zhang Huvue , Zhu Yanpeng
Published: March 2020

The wind-induced performance response of large-span truss curved roofs is extremely complex and changes obviously under wind load. This paper has taken the large-span steel roof of Liu Zhaike highway toll station as an example to analyze by both numerical simulations and field tests of responses of the steel canopy under wind load. In this case, simulated analysis results using finite element software were calibrated and verified by the field test results. In addition, a new method of large structure field testing was proposed which obtained the internal force and displacement of the canopy structure. Moreover, this paper analyzed and determined the actual stress state of the rectangular pipe truss. Finally, the safety condition of the roof was evaluated based on the monitoring data and the simulation of the finite element model. And the analysis methods provides references for similar engineering field tests, as well as guidance for the operation and maintenance for this project.
RESPONSE SURFACES FOR PROPERTIES OF CONCRETE WITH CLAY BRICK POWDER AS SUBSTITUTE FOR CEMENT
Authors: Olofinnade Oluwarotimi , Ede Anthony , Jolayemi Kayode , Oyeyemi Kehinde , Ndambuki Julius
Published: March 2020

This study examined the application of pulverize clay brick wastes as alternative constituent for Portland cement replacement in green concrete production using the response surface methodology (RSM). The adopted response surface approach is central composite design (CCD). The statistical models were developed between the concrete constituents (clay brick powder and water cement ratio) and their response variables (slump, compressive and split tensile strength). Relationships were established and mathematical models in terms of actual factors from predicted responses were developed. The influence of the considered factors on the properties of response were visually observed from the contour and response surface plots. The statistical models of experimental values clearly depict that the obtained experimental values are in close agreement with the predicted values, which validates the response surface models with desirability value of 1. The results show that pulverized clay brick waste have significant influence on the properties of concrete than the water cement (w/c) ratio, however, a declining trend was seen for all analyzed concrete properties. In addition, this study showed that the pulverized waste brick can be used as alternative substitute for Portland cement up to 20% in the production of sustainable concrete.
REVIEWING GOVERNMENT INITIATIVES ON IMPLEMENTING SUSTAINABLE INFRASTRUCTURE CONSTRUCTION
Authors: Willar Debby , Pangemanan Daisy D. G.
Published: March 2020

Sectoral development activities, lack of standards on eco-systematic approach, prioritizing short-term outcomes, and ignoring the holistic and comprehensive prospects of sustainability have led to environmental degradation. Therefore, the Indonesian government has realized the importance of implementing sustainable development concepts in every phase of infrastructure project life-cycle. This paper reviews the existing government regulations on sustainable construction implementation guidelines, which underlie the execution of infrastructure project throughout five phases of project life-cycle, namely (1) programming, (2) technical planning, (3) construction execution, (4) utilization, and (5) demolition. A relook at existing regulation in term of providing more technical concepts on implementing the sustainable principles throughout the infrastructure project life-cycle is necessary to help both the construction services users and providers in implementing sustainable construction principles in Indonesia. The outcome of this review can serve as a guide to develop a technical concept for the implementation of the sustainable construction in infrastructure projects in order to create sustainable development in Indonesia.
REVISITING SYSTEMS AND APPLICATIONS OF ARTIFICIAL NEURAL NETWORKS IN CONSTRUCTION ENGINEERING AND MANAGEMENT
Authors: Shojaei Alireza , Mahdavian Amirsaman
Published: March 2020

Artificial neural networks have been widely used for modeling and simulation of different problems in the construction industry, including, but not limited to, regression, clustering, and classification. They provide solutions for complex problems where other modeling methods often fail. For instance, they can capture nonlinear and complex relationships between the variables while many traditional modeling methods fail. However, they have their own limitations. They often can only be trained for a specific problem with a predetermined number of inputs and outputs. As a result, any change that requires an update in the architecture of the network cannot be automatically done and require human intervention. The recent developments in the field of artificial neural networks resulted in new concepts such as neural architecture search, reinforcement learning, and neuroevolution. These new areas can provide new methods for solving past and existing problems facing the construction industry in a more efficient, elegant, and versatile manner. One of the main contributions of the recent developments is networks that can optimize their own architecture and networks that are able to evolve and change their architecture. This paper aims to briefly review the application areas of the artificial neural networks in construction engineering and management and discuss how the recent developments in this field can be applied and provide better solutions.
AN INVESTIGATION OF THE CONTRACTUAL ROADWAY SAFETY TERMS IN TRANSPORTATION PPP PROJECTS
Authors: Shang Luming , Abdel Aziz Ahmed M.
Published: March 2020

Roadway safety is an important aspect of all transportation facilities. With operation and maintenance becoming contracted roles under public-private partnerships (PPP), it is expected that safety rates will improve beyond those experienced in traditional delivery. The international experience shows that PPPs experienced mechanisms designed to provide safer roads. In the United States, PPP is gaining momentum and several states initiated PPP projects. While studies show the potential of PPPs for improving cost efficiency and expediting the delivery time, few researches investigated the correlation between PPP and roadway safety. To fill the gap, this study investigated seventeen PPP projects through content analysis of their agreement and procurement documents. The findings show that PPP projects were lacking further consideration toward safety beyond what is normally available in traditional delivery. Safety was an objective in most (76%) of the projects, however, without direct mechanisms to implement such objective. Around half of the projects have mentioned safety as part of proposal evaluation but only two projects have assigned points/weights in the evaluation. None of the projects provided for a direct link between the compensation to the achievement of improvements in the safety rates. Generally, PPPs are meant to provide public agencies with means to achieve particular objectives. It is recommended to use the particulars of PPPs in performance measures and payment mechanisms to enforce roadway safety in highways infrastructure.
SEISMIC PERFORMANCE OF STRUCTURAL FRAMES AND JOINTS IN WOOD TALL BUILDINGS
Authors: Saleh Eman , Mohammadi Jamshid
Published: March 2020

There has been a growing interest in using wood in tall buildings by employing cross-laminated timber (CLT) in a structure’s moment frame system. However, still much needs to be learned about the performance of CLT frame systems subject to lateral loads such as earthquakes. The ductility needed in CLT frames in seismic load environments is primarily provided through connections. Thus, a proper connection detail is required to ensure an adequate seismic response, especially at extreme loads. Current strength specifications of connectors are mainly applicable in cases of pure tension or shear; while in real applications, connections are subjected to a combination of these loads. This paper is part of analytical and simulation studies on seismic performance of wood structural frames being conducted at Illinois Institute of Technology. These studies include simulations to investigate: (1) Moment-resistance capacity of CLT panels; and (2) Resistance capacity of typical joints used in CLT frame systems. Limited experimental data available on a 6-story wood frame system are considered as a means of verification of the aforementioned analytical investigations. Focus of this paper is specifically on the significance of interaction between tension and shear as reported in literature. Several interaction equations as implemented in current analytical models for pushover analysis of CLT frames are explained and their adequacy to predict the nonlinear behavior of CLT panels under lateral loads is discussed.
SEMI-COMPOSITE STRUCTURES FOR SEWER RENOVATION
Authors: Nakano Masaaki , Shi Zihai , Nakamura Yukari , Iwasa Yukitoshi , Uji Kimitaka
Published: March 2020

In the composite pipe construction method defined in the Japan Sewage Works Association's Design and Construction Guidelines for Sewer Pipe Rehabilitation, a liner pipe is constructed inside an existing sewer and the annular space behind the liner is filled with cementitious grout under pressure to form a highly integrated structure. The Guidelines for sewer renovation in Japan define a composite pipe as a composite structure that requires complete integration between liner materials and an existing pipe. However, in general, owing to the refinement of the small and enclosed working space inside sewers and the significant extension of the pipe to be renovated, mechanical shear connectors are not used to rigidly connect a renovation layer with an existing pipe. To fully explore the advantages of the composite pipe method in sewer renovation while maintaining safe design, a semi-composite structure has been applied in the renovation design of aging sewers using nonlinear FEM analysis for more than 50 sewers (over a total length of 300 km), primarily in big cities in Japan. This paper focuses on the mechanics of the structure.
SOME PROPERTIES OF REACTIVE POWDER CONCRETE MADE WITH RECYCLED AGGREGATE
Authors: Hasan Shatha
Published: March 2020

An experimental study was carried out to investigate, the strength properties, of recycled aggregates for use in reactive powder concrete (RPC), to better understand the properties of reactive powder concrete with recycled aggregates used as a substitution material for normal sand in reactive powder concrete. The effects of variable parameters on these properties were carefully studied which are the percent of recycled fine aggregate (0%, 25%, 50%, and 75%) as a partial replacement by weight of normal sand, recycled fine aggregate (50%) as a partial replacement by weight of glass sand, and two different curing (20, 90 °C). The inclusion of using reactive silica sand powder leads to a considerable increment in both compressive and tensile strength for recycled reactive powder concrete (RRPC) and the heat treatment improves the properties of the RPC and RRPC considerably. Finally, the results indicated that it is possible to produce reactive powder concrete from recycled aggregate depending on the strength, the results show to suggest only a gradual lowering in compressive and splitting tensile strength.
STRENGTH PROPERTIES OF DURABLE CONCRETE MADE WITH VARIOUS ALTERNATIVE CEMENTITIOUS MATERIALS
Authors: Yoshitake Isamu , Inoue Shun , Miyamoto Keisuke , Yamato Koichiro
Published: March 2020

Many researchers investigated various concrete made with the cementitious materials, hence the effects of various admixture are well known. Most researches focused on an alternative cementitious material, tested concrete properties by varying the cement-replacement ratio. The optimum cement-replacement ratio may be different by each admixture. The present study examined the strength properties of concrete incorporating various admixtures. The cementitious materials tested in this study were fly-ash, blast furnace slag powder, silica-fume, limestone powder, and an artificial admixture which has high resistance to chloride attack. First, fundamental properties of the concrete incorporating the admixture were summarized referring to previous durability tests. Second, the strength properties of concrete made with some cement-replacement ratios by the cementitious materials were examined. In addition, alternative cement efficiency factors (k) of each cementitious material were estimated.
STUDY AND ANALYSIS OF INCENTIVES FORM STATE-OF-THE-ART NET-ZERO ENERGY HOUSES
Authors: Rafsanjani Davoud Sahban , Sharma Deepak , Tran Tung , Nguyen Phoung
Published: March 2020

Over the past several years, the US Energy Information Administration (EIA) has reported that buildings consume about 40% of the total energy produced. As a consequence, buildings emit high volumes of carbon dioxide (CO2). The ever-increasing population demand implies that buildings will continue their consumption and emit gasses in high proportions if appropriate steps are not taken. Federal and state agencies offer various financial incentives to motivate homeowners to adopt energy efficient alternatives. In this research, major cash inflows and outflows are identified for Net Zero Energy Houses (NZEH) and breakeven analysis is conducted by considering that the houses are constructed in two US states having significantly different climatic conditions. The cash inflows considered in this research are from Federal and State incentive programs and savings generated by adopting NZEH. Sensitivity analysis is also conducted to determine the impact of variation in in government incentives, market interest rate, electricity rates and rate of construction. Results show that when some of the incentives are utilized the breakeven for a NZEH construction could be less than 4 years. Sensitivity analysis shows that the breakeven is most sensitive to changes in government incentives and market interest rate.
STUDY OF A MULTIPLE-TUNED MASS DAMPER FOR EXCESSIVE FLOOR VIBRATIONS MITIGATION
Authors: Setareh Mehdi , Renard Stephanie
Published: March 2020

Excessive vibration of architectural structures due to human movements has become an important serviceability issue. Tuned Mass Dampers or Vibration Absorbers have been used to mitigate the problem. This paper presents studies on an easy to fabricate, assemble and tune Multiple Tuned Mass Damper (MTMD) that can alleviate vibrations due to the excitations of several modes of a floor system. Using a test floor at the Virginia Tech Vibration Testing Laboratory, a number of experiments were conducted with the MTMD active and inactive. Different excitations generated by an electrodynamic shaker, and people walking on the floor were used. The vibration tests were repeated at various times to check the consistency of the MTMD performance. The measured reduction in floor vibrations were compared to those predicted based on the analytical equations. The results have shown that the device is effective in reducing floor vibrations due to human movements in spite of its small mass compared to the mass of the test floor.
ANALYSIS OF IMPEDIMENTS TO A SUCCESSFUL CONSTRUCTABILITY PROCESS IN HIGHWAY CONSTRUCTION
Authors: Minchin R. Edward , Samsami Reihaneh , Tran Dan , D’Angelo Dan , Scott Sidney , Tian Yifeng , Im Haekyung , Russell Jeffrey
Published: March 2020

The US Federal Highway Administration (FHWA) Every Day Counts Program (EDC) has resulted in state Departments of Transportation (DOTs) putting evermore emphasis on speeding up the delivery of highway and bridge construction projects for use by the driving public. This has resulted in an increase in the use of integrated project delivery methods and adding alternative technical concepts (ATCs) to traditional design-bid-build (DBB) contracts. ATCs have exhibited great potential for delivering substantial benefits like cost savings, increased constructability, and quicker project delivery. Previous research has found that knowledge of project constructability was lacking in state DOT planning, programming, and environmental staffs. At the same time, the permitting process for several government agencies has become increasingly restrictive. The intent of this paper is to report on the research team's progress in an ongoing effort to furnish the US government with a uniform set of guidelines for the application of the constructability process during all phases of project development and delivery. The research uses surveys, focus groups and interviews to determine which states have implemented formal programs to ensure that the constructor is furnished with a set of contract documents that affords said constructor with the best possible opportunity to successfully construct the project with the highest quality standards, within the contract duration and without exceeding the construction budget.
TEAMWORK IN SUCCESSFUL CONSTRUCTION MANAGEMENT OF ROAD IMPROVEMENT PROJECTS
Authors: Seniwongse Sinit
Published: March 2020

This paper addresses the methodology and the art of construction management of road infrastructure projects from the viewpoint of practicing engineers using teamwork amongst organizations, which include owners, design engineers, consultants, construction managers, contractors, subcontractors, vendors, local residents, publics, and owners of other utilities. The author points out that most construction management text books and research papers have been written by academia without actual construction or management experience, and that successful construction management of infrastructures is not a simple task. To demonstrate this point, the collapse of the roof of the tunnel in the Big Dig project in Massachusetts and the collapse of the pedestrian bridge during installation in Florida in 2017 are mentioned. Both collapses cost the lives of road users and millions of dollars in litigations. The paper gives the factors contributing to successful teamwork as leadership, communication, collaboration, trust, transparency, common goal and mutual benefits. Using these traits, the author describes the construction management using teamwork concept in the successful completion of many road restoration projects in Chicago. It is concluded that the approach can be used equally well in other infrastructure projects of any sizes in USA or any other countries.
TECHNICAL AND ENVIRONMENTAL ASSESSMENT FOR SOIL STABILIZATION USING COAL ASH
Authors: Gómez Diana , Carvajal Gloria , Balaguera Alejandra , Arias Yhan Paul
Published: March 2020

In most Latin American countries, low-volume roads are composed of unpaved roads; this is considered a problem of economic, social and environmental interest. There are different stabilization alternatives for this type of roads with traditional materials, i.e., Portland cement (OPC) and lime (L), both of which have a high environmental impact due to anthropogenic CO2 emissions. This paper presents the results of the environmental assessment of an industrial residue Coal Ash (CA) with pozzolanic characteristics. The residue was alkaline activated with Ca(OH)2 from commercial lime (L). The binary system (CA+L) is called (CLM) and forms a material with cementing properties, and when it is mixed with soil, it increases the capacity to support loads. The CLM as a soil stabilizer is proposed along with the modification of some construction processes associated with lime technology and Portland cement. Finally, a technical and environmental comparison is made for conventional stabilizers and the binary system CLM. The results showed that stabilization of a silty soil with CLM can achieve a reduction of 58% and 75% in CO2 emissions when compared with L and OPC, respectively.
TECHNOLOGICAL AND SOCIAL RETROFIT STRATEGIES FOR THE PUBLIC RESIDENTIAL BUILDINGS OF THE SECOND POST-WAR
Authors: Di Sivo Michele , Ladiana Daniela , Santi Giovanni , Rrjolli Lediana
Published: March 2020

This experimental study on the renewal of post-World War II suburban areas addresses the theme of the technological retrofitting of buildings, focusing on typological features, construction techniques and, more in general, of all aspects that fail to meet the needs of contemporary living. An initial examination of Italian and international case studies helped to identify possible guidelines for the optimization of urban renewal activities. The guidelines were tested by applying them to a case study: a 1950s-era neighborhood in the city of Pisa. The study undertaken highlights the need to consistently integrate all of the activities that affect the building structures-consolidations and static adjustments, improvement of energy efficiency, functional and spatial adaptation-and that work towards strengthening social integration by taking into account the specific needs of the individual. The work is implemented on individual buildings and urban areas, with the aim of improving the local identity characteristics. The suggested approach is that of a circular economy, which helps to reduce the impact on the environment, mainly through the extensive use of recycled materials. The proposed experiment thus aims to test the resilience of buildings following their seismic, energy and functional updating, including sociological and environmental psychology assessments, with particular attention to vulnerable users, in order to find solutions capable of promoting social inclusion.
THE IMPORTANCE OF THE PROPERTY MANAGEMENT COMPANIES AS CONDOMINIUM JURIDICAL PERSONS
Authors: Aramraks Kanyapa , Gondo Tomoyuki
Published: March 2020

This study examined Bangkok's condominium management system with a particular focus on the role of property management companies as members of juridical persons. The number of condominiums in Bangkok has been proliferating rapidly, particularly in areas near the mass rapid transit system. The Thailand Condominium Act requires that a condominium juridical person be registered upon transfer of ownership of the first condominium unit. This study's analysis of data collected from interviews with 16 condominium juridical persons found that there are three types: 1) property management companies; 2) juridical person employees; and 3) a combination of 1) and 2). All but one condominium-which used the mixed management type-had hired property management companies to oversee management and maintenance. Reasons cited for this overwhelming preference included insufficient management and maintenance knowledge among juridical employees, and limited beneficial connections with outsourcers and suppliers among juridical person employees. The interview results demonstrate that the responsibilities of property management companies extend beyond their job description and include caring for residents, seeking solutions for condominium problems, and creative thinking for innovative proposals for alternative management practices.
VERIFICATION OF SIGNAL POLE SHAFT FOUNDATION LRFD DESIGN USING FINITE ELEMENT METHOD
Authors: Hou Kuang-Yuan , Fu Chung C. , Ye Yunchao , Xu Chaoran
Published: March 2020

This study presents verification methods of current shaft foundation design under linear lateral and torsional loads. Shaft is used as a foundation to support mast arm signal pole structure and transfer loads from superstructures to ground. The capacity of current shaft foundation deployed in the State of Maryland is re-verified due to higher sub-structural strength requirement against super-structural fatigue proposed from the AASHTO LRFD Specification (2015). The shaft foundation verification includes embedment length and torsional capacity. For embedment length check, lateral reactions between soil and shaft are verified by comparing analytical method and finite element method. Wind-induced torque is a design concern for the shaft of a single pole cantilever structure. However, torsional capacity of the shaft foundation of signal pole structures is rarely mentioned in the current design specification. By verifying finite element models with analytical method, torsional effect is further simulated to finite element models to evaluate the adequacy of current shaft foundation design. Results show existing design of shaft foundation could meet requirements to resist lateral force under extreme conditions. For torsional effect, current torsional capacity is less than the torque induced by wind load in the worst soil conditions.
CONTENTS UNDER PRESSURE: DISTINGUISHING IMPREGNATED FIRE-RETARDANT-TREATED WOOD FROM SURFACE-APPLIED TREATMENTS
Authors: Eckhoff Mike
Published: March 2020

Increasing populations combined with decreasing developable plots are leading to higher real estate prices. Communities are attempting to address these higher prices by increasing the number of residential units per acre. One way to increase the supply is to use fire-retardant-treated wood (FRTW) to build larger and taller structures. However, as FRTW is increasingly being used, substitute products that do not meet the definition of FRTW in the building codes are also being increasingly used. How does one distinguish the two? By relying on knowing how FRTW is manufactured, where it can be used, and on building code requirements, responsible parties will better understand why FRTW is different from these products and how to verify that only code-compliant, chemically impregnated FRTW is used in larger, taller structures.
FATIGUE LIFE ANALYSIS OF RAIL-WELDS USING LINEAR ELASTIC FRACTURE MECHANICS
Authors: Alamnie Mequanent M. , Endalemaw Yalelet
Published: March 2020

The initiation and growth of fatigue cracking is mainly due to high stress concentration, heterogeneity and poor quality of weld. The detection and rectification of such weld defects are major concerns of rail network managers to reduce potential risk of rail breaks and derailments. To estimate the fatigue life of welded joints and to analyze the progress of fatigue cracks, a fracture mechanics-based analysis and fatigue models were developed using Finite Element Analysis. The initial flaw is obtained from a sample weld using ultrasonic flaw detecting machine test. Linear Elastic Fracture Mechanics (LEFM) approach based on the Paris law was applied to determine critical crack size and the number of cycles to failure using FRANC3D software. The inspection interval of rail welds before fracture (failure) was suggested based on reliability and life cycle analysis that correspond with minimum overall cost and frequency interval. It is recommended that fracture-based models in combination with reliability analyses can be a sustainable infrastructure decision-making algorithm.
A COMPARISON BETWEEN PROBABILISTIC AND POSSIBILISTIC NUMERICAL SCHEMES FOR STRUCTURAL UNCERTAINTY ANALYSIS
Authors: Sekkak Hamza , Modares Mehdi
Published: March 2020

Analysis of a structure is a crucial procedure to ensure its reliable design and performance. Because of complexities present in the closed-form structural analysis methods, numerical schemes have become the standard of practice. These schemes are generally performed deterministically. However, the input parameters defining the material and geometric properties may possess uncertainties. They can arise from various sources including modeling, manufacturing, and construction errors. The quantification of uncertainties is generally based on either probability theories (using random variables) or possibility theories (using interval and fuzzy variables). In this work, the finite-element-based probabilistic and possibilistic methods are discussed and compared. A case study of static and dynamic uncertainty analyses of a structure using the aforementioned schemes is performed. The results of those analyses suggest that the incorporation of uncertainty in the analysis provides a higher level of confidence. Moreover, they are compared for both accuracy and computational efficiency. Based on the results, it is observed that the determination of approach must be based on the problem complexity as well as the level of available information.
PREDICTION OF UNEVEN DISTRIBUTION OF SNOW LOAD BASED ON GENERALIZED REGRESSION NEURAL NETWORK
Authors: Ren Zhicheng , Zhang Qingwen
Published: March 2020

At present, there are mainly three research ways on the distribution of snow load: field measurement, experimental simulation, and numerical simulation. They all need expensive equipment, specimen model used only once, and slight defective simulation software. Artificial Neural Networks (ANNs) rely on a large number of input functions to estimate unknown or known occurrences. This paper applies ANNs to predict the uneven distribution of snow loads. First, the snow load database is collected and set up, including all the data from field measurement and experimental simulation. Second, part of the data from the 1 m3 model is used as a training set to train Backpropagation Neural Networks (BPNN) and Generalized Regression Neural Networks (GRNN). The parameters of the two neural networks are determined (such as the smoothing factor in the GRNN), and the rest of the data is used to examine the model; the prediction and measurement results of the two models are compared. Finally, based on different wind direction angles and wind speed, a GRNN model is established to predict the uneven snow load distribution. Through comparative analysis, GRNN is more suitable for predicting the uneven distribution of snow loads, especially in predicting snow thickness. In particular, the prediction effect of the model on the snow load distribution trend is good, and the prediction ability of the neural network model is displayed.
THE USE OF LIFE CYCLE ASSESSMENT TO ACHIEVE SUSTAINABLE CONSTRUCTION
Authors: Ohiomah Ifije , Aigbavboa Clinton , Zwane Thulisile , Aghimen Douglas
Published: March 2020

This study assesses the benefit of sustainable construction and the use of life cycle assessment (LCA) in the South African construction industry to achieve sustainable construction. The data used in this was derived from both primary and secondary resources. The primary data was collected through a questionnaire approach. The study revealed that LCA could be used for product comparison, product development, formulating of product eco-labels, evaluating construction processes and decision-making processes in the construction industry concerning materials. Furthermore, the study revealed that LCA has various strengths, challenges and weakness, this is due to the fact that there is a requirement of the high quality of knowledge and data when conducting a detailed LCA study. However, this study revealed that life cycle thinking is a cornerstone for developing policies and programs, which meet sustainability criteria and there is a great room for the development and use of LCA in the South African construction industry. Therefore, it is recommended that the South African Construction industry invest more in environmental tools such as LCA.
ASSESSMENT OF BUILDING INFORMATION MODELING UPTAKE IN THE MANAGEMENT OF CONSTRUCTION PROJECTS
Authors: Ojelabi Rapheal Abiodun , Omuh Ignatius Owoicho , Afolabi Adedeji Olushola , Tunji-Olayeni Patience Fikiyemo
Published: March 2020

The need for digitization of industries' production process has been given high attention in the 21st century. This is due to the upsurge in technology in the present age. Industries which include manufacturing, telecommunication and aviation among others have set the pace for others to follow in the use of digital tools in their production process. Therefore, this study is aimed at examining the awareness and level of uptake of a digital tool like Building Information Modeling (BIM) in the management of construction project and the challenges limiting its use within the built environment. The study adopted a survey method by randomly selecting 120 construction practitioners in construction firms operating in Lagos state Nigeria. Likewise, 120 structured questionnaires were distributed to the targeted respondents, however, 100 questionnaires were retrieved. The data collected from the survey were processed using Mean item score, percentage, and relative importance index. Findings garnered from the study revealed that construction organization awareness of the BIM tool is very high, however, its uptake in the construction industry is not encouraging. It further revealed that the driving factor in encouraging the BIM adoption cut across the government, the construction industry and the clients. In conclusion, the study recommends that the trio should provide an adequate support structure and push for BIM implementation in construction project delivery.
ASSESSMENT OF THE TARGET RELIABILITY DEPENDING ON STRUCTURAL PROPERTIES
Authors: Ozola Lilita , Zirnova Dana
Published: March 2020

Although the establishment of the maximum acceptable failure probability for structures is not a mandatory requirement in design, it is important to develop a unified system for safety differentiation of bearing structures in public buildings so that people can feel equally safe in all the countries of the European Union. Differences from country to country in safety requirements declared by national codes may be permissible regarding the economic losses only. This study is aimed to clarify the understanding of how to examine a structure regarding the weakest link (element, fastener, system) in the limit state. In this study the authors propose a method for differentiation of structures regarding the variation of bearing capacity, which variates depending on a number of characteristics involved, and the failure mode anticipated when overloading takes place. Variation of bearing capacity is expressed in terms of reliability index variating correspondingly. Differentiation of the safety regarding failure modes anticipated has been developed using the toughness indices as a decisive criterion for the comparable assessment of structural compositions regarding the ability to sustain in the limit state for some period of time. Also, a criterion of possible redistribution of internal forces in the limit state is taken into account. The developed example of the assessment of the target reliability of structures is presented.
ASSET CONDITION ASSESSMENT MODEL FRAMEWORK FOR HEALTHCARE FACILITIES
Authors: Salem Dalia , Elwakil Emad
Published: March 2020

The poor healthcare facilities performance costs the USA tens billions of dollars each year. There are several factors affect the critical assets of healthcare facilities such as the physical condition of the facility, infection prevention, life safety, and hospital revenue loss. The objective of this research is to develop an asset condition assessment model for healthcare facilities. The model identifies several factors, especially the condition, capacity, and code compliance of a facility's infrastructure. The asset condition assessment model has been developed based on the mechanical, electrical and plumping systems and evaluates the asset condition based on its age, life expectancy, recent condition assessment and energy efficiency among other factors. The data was collected from different hospitals in Indiana. This model has been developed using the Regression analysis technique. The model has been validated through analytical and mathematical methods. Results showed average validity at 88.32%. The developed model will help the healthcare facilities managers to prioritize the budget allocation and to reduce the impact of consequences of asset failure, which will improve the healthcare infrastructure performance.
BEHAVIOR OF M 50 GRADE SELF-COMPACTING CONCRETE DEVELOPED USING PORTLAND SLAG CEMENT AND METAKAOLIN
Authors: Nalla Sravya , Maganti Janardhana , Pasla Dinakar
Published: March 2020

Self-compacting concrete (SCC) is a revolutionary development in concrete construction. The addition of mineral admixtures like metakaolin, which is a highly reactive pozzolana to the SCC mixes, gives it superior strength and durability. The present work is an effort to study the behavior of M50 grade SCC by partial replacement of Portland Slag Cement (PSC) with metakaolin. Its strength and durability aspects are comparable with a controlled concrete (without replacement of cement). In the present work, a new mix design methodology based on the efficiency of metakaolin is adopted. The optimum percentage replacement of cement with metakaolin is obtained based on compressive strength test results. The influence of metakaolin on the workability, compressive strength, splitting tensile strength and flexural strength of SCC and its behavior when subjected to elevated temperature was investigated through evaluation against controlled concrete and non-destructive testing. From the test results, it was observed that incorporation of metakaolin at an optimum dosage satisfied all the fresh properties of SCC and improved both the strength and durability performance of SCC compared to controlled concrete.
BEST PRACTICES FOR THE DESIGN PROCESS FOR THE HORIZONTAL DESIGN-BUILDER
Authors: Migliaccio Giovanni C. , Minchin R. Edward , Gatti Umberto C. , Ptschelinzew Lourdes , Atkins Kenneth E. , Hostetler Gregory A.
Published: March 2020

In early 1990s, the American driving public insisted that planned highway and bridge projects be completed quicker than was possible using the Design-Bid-Build (DBB) construction project delivery system, which had dominated the industry since 1930s. This led state Departments of Transportation (DOTs) to explore fast-track methods of construction. In late 1980s, some DOTs had experimented with Design-Build (D-B) delivery system. Forty-two state DOTs and numerous county and municipal transportation agencies now use the system and it remains the most popular integrated construction project delivery system in US transportation construction despite Federal Highway Administration efforts through the Every Day Counts initiatives to popularize newer methods such as Construction-Manager-as-General-Contractor and Alternative Technical Concepts. Its popularity is due to the speed with which projects move from conception through to completion and the ability through early contractor participation to implement innovative ideas that improve quality and further enhance the speed of the project. With all this speed, however, the design process has struggled to stay ahead of construction, especially when the Design-Builder is faced with new responsibilities such as Right-of-Way acquisition, the National Environmental Policy Act (NEPA) process, the environmental permitting process, utility re-location, etc. This paper recounts the research performed by a team led by the University of Florida to produce a guidebook to help both design-builder and owner with the design management process for transportation infrastructure construction.