Civil Engineering Sector Research Articles

Influence of Selected Determinants on the Financial Structure in the Civil Engineering Companies in the Selected Countries

Analyzing and deciding on capital structure is one of the core activities of any company, as evidenced by the vast amount of research. Each sector is characterized by a different capital structure. This article deals with the impact of profitability, non-debt tax shield, GDP growth rate, and inflation rate on the overall, long-term, and short-term debt of medium and large civil engineering companies. The analysis is carried out for the period 2009–2018 on eleven selected economies, including the extended Visegrad Group and Estonia, Lithuania, and Latvia. The input data is obtained from the Orbis database and the World Bank database. Panel regression using the Generalized Method of Moment is used to analyze the influence of selected determinants on debt.

Steel rebar categories data and statistical properties of Nigerian reinforcement used for structural strength

The paper was aimed at evaluating effect of cost prices of reinforcement on its strength since dispersal in the size geometry of locally available and imported bars is very essential to the development of stable standard of practice for both civil and building engineering sector. Steel rebar from some locations in Lagos state, Nigeria was obtained so as to determine its cost price and strength. The results disclosed that both yield and ultimate loads of 45.67 and 65.54% respectively, as regards to flexural strength, Ogba reinforcement is the highest.

Accident Rate as a Measure of Safety Assessment in Polish Civil Engineering

Civil engineering is characterised by high volatility with respect to working conditions, which are the source of many threats to worker life and health and contribute to high accident rates. The purpose of this paper is to analyse and evaluate the phenomenon of accidents in Polish civil engineering and define the direction of changes that should occur in the safety area. The studies included in this research covered the years 2004–2018. The following indicators were used to assess the accident rates: (1) The total number of persons injured in workplace accidents and this total divided into fatal, severe, and minor accidents; (2) indicators of frequency of accidents in total and this total divided into minor, severe, and fatal accidents; (3) and an indicator of the severity of accidents. From the analysis of statistical data for the years 200–2018, the changes in accident rate parameters demonstrate the continuous improvement of workplace safety in the Polish civil engineering sector. From the analysed data from the 15 years, a clear decrease in the value of the applied indicators is apparent, including both the number of people involved in accidents and the frequency and severity of accidents.

The Potential of Ladle Slag and Electric Arc Furnace Slag use in Synthesizing Alkali Activated Materials; the Influence of Curing on Mechanical Properties.

Alkali activation is studied as a potential technology to produce a group of high performance building materials from industrial residues such as metallurgical slag. Namely, slags containing aluminate and silicate form a useful solid material when activated by an alkaline solution. The alkali-activated (AA) slag-based materials are promising alternative products for civil engineering sector and industrial purposes. In the present study the locally available electric arc furnace steel slag (Slag A) and the ladle furnace basic slag (Slag R) from different metallurgical industries in Slovenia were selected for alkali activation because of promising amorphous Al/Si rich content. Different mixtures of selected precursors were prepared in the Slag A/Slag R ratios 1/0, 3/1, 1/1, 1/3 and 0/1 and further activated with potassium silicate using an activator to slag ratio of 1:2 in order to select the optimal composition with respect to their mechanical properties. Bending strength of investigated samples ranged between 4 and 18 MPa, whereas compressive strength varied between 30 and 60 MPa. The optimal mixture (Slag A/Slag R = 1/1) was further used to study strength development under the influence of different curing temperatures at room temperature (R.T.), and in a heat-chamber at 50, 70 and 90 °C, and the effects of curing time for 1, 3, 7 and 28 days was furthermore studied. The influence of curing time at room temperature on the mechanical strength at an early age was found to be nearly linear. Further, it was shown that specimens cured at 70 °C for 3 days attained almost identical (bending/compressive) strength to those cured at room temperature for 28 days. Additionally, microstructure evaluation of input materials and samples cured under different conditions was performed by means of XRD, FTIR, SEM and mercury intrusion porosimetry (MIP).

Atmospheric Boundary Layer Wind Tunnel of Slovak University of Technology in Bratislava

Aerodynamics is a relatively young scientific discipline, which started developing in the 50´s of last century. There are known several methods for calculating and measuring of the aerodynamic variables – in-situ measurements, wind tunnel measurements, CFD simulations and calculations according to national standards. Each method has its advantages and disadvantages. Nowadays a large focus is on experimental verifying the findings achieved with calculations help and CFD simulations. One of the verification possibilities are measurements in wind tunnels. The submitted paper deals with construction and using of the wind tunnel by the Slovak University of Technology in Bratislava. This device was put into operation after experimental verification in 2012, so this wind tunnel is one of the newest of its kind in Europe. The concept of the construction of individual structural elements and the wind tunnel parts has been designed in collaboration with the Aeronautical Research and Test Institute (Czech Republic) and was based on previous made analysis of aerodynamic tunnels. Its structure was designed and realized by Konštrukta Industry (Slovak Republic). We could it characterized as atmospheric boundary layer wind tunnel with open test section. It is unique with two test sections – front and back measuring space, where the front measuring space is used for uniform flow and the back measuring space is used for turbulent flow. That is why it is not only usable in the civil engineering sector (buildings, bridges, chimneys etc.), but also in city urbanism (pedestrian wind comfort and wind safety, dispersion of air pollutants), aircraft and automotive industries.

Intelligent materials in modern production – Current trends for thermal shape memory alloys

Abstract Thermal shape memory alloys show extraordinary material properties and can be used as actuators, dampers and sensors. Since their discovery in the middle of the last century they have been investigated and further developed. The majority of the industrial applications with the highest material sales can still be found in the medical industry, where they are used due to their superelastic and thermal shape memory effect, e.g. as stents or as guidewires and tools in the minimal invasive surgery. Particularly in recent years, more and more applications have been developed for other industrial fields, e.g. for the household goods, civil engineering and automotive sector. In this context it is worth mentioning that for the latter sector, million seller series applications have found their way into some European automobile manufacturers. The German VDI guideline for shape memory alloys introduced in 2017 will give the material a further boost in application. Last but not least the new production technologies of additive manufacturing with metal laser sintering plants open up additional applications for these multifunctional materials. This paper gives an overview of the extraordinary material properties of shape memory components, shows examples of different applications and discusses European trends against the background of the most recent standard and new production technologies.

The ALARP Principle in the Cost-Benefit Analysis for the Acceptability of Investment Risk

The process of allocating financial resources is extremely complex—both because the selection of investments depends on multiple, and interrelated, variables, and constraints that limit the eligibility domain of the solutions, and because the feasibility of projects is influenced by risk factors. In this sense, it is essential to develop economic evaluations on a probabilistic basis. Nevertheless, for the civil engineering sector, the literature emphasizes the centrality of risk management, in order to establish interventions for risk mitigation. On the other hand, few methodologies are available to systematically compare ante and post mitigation design risk, along with the verification of the economic convenience of these actions. The aim of the paper is to demonstrate how these limits can be at least partially overcome by integrating, in the traditional Cost-Benefit Analysis schemes, the As Low as Reasonably Practicable (ALARP) logic. According to it, the risk is tolerable only if it is impossible to reduce it further or if the costs to mitigate it are disproportionate to the benefits obtainable. The research outlines the phases of an innovative protocol for managing investment risks. On the basis of a case study dealing with a project for the recovery and transformation of an ancient medieval village into a widespread-hotel, the novelty of the model consists of the characterization of acceptability and tolerability thresholds of the investment risk, as well as its ability to guarantee the triangular balance between risks, costs and benefits deriving from mitigation options.

PLANT, ROAD CONSTRUCTION, TRAFFIC, AND GENERAL HEALTH AND SAFETY: PERSPECTIVES OF GENERAL CONTRACTORS

Statistics and various studies indicate that plant, road construction, and traffic safety are major issues in terms of construction H&S. Furthermore, motor vehicle accidents (MVAs) during employment are the dominating cause of fatalities in South African construction. A study was conducted among general contractor (GC) members of a civil engineering sector employer association using a self-administered questionnaire. The salient findings include: plant, road construction, and traffic safety are important aspects in respondents' organizations; plant is the more important of the three aspects; traffic accidents account for a fair percentage of total accidents, and respondents' organizations use a range of such devices and equipment to realize plant, road construction, and traffic safety. Conclusions include: respondents' organizations are managing the three aspects, and H&S programs must focus thereon. Recommendations include that respondents' organizations need to focus on drug and other substance abuse testing and medicals, and that plant, road construction, and traffic safety must feature prominently in H&S programs.

Considerations over the Italian road bridge infrastructure safety after the Polcevera viaduct collapse: past errors and future perspectives

In the last four years, Italy experienced the collapse of five road bridge: Petrulla viaduct (2014), Annone (2016) and Ancona (2017) overpasses, Fossano viaduct (2017) and Polcevera (2018) bridge. Although for deeply different reasons, the collapses occurred can all been gathered into the same common cause: the (lack of) knowledge of the effective structural condition, a serious problem that affects existing constructions. As it will be shown in the paper, different problems such as missing of the as-built designs, an appropriate construction and movement precautions, a heavy vehicle checking, and a material decay monitoring can nevertheless be addressed as an inadequate knowledge of what is happening to/in the structure. In the first section, the paper will report a short description of the failures for the five bridges, while in the second part a main set of problems involved in bridge safety and maintenance will be discussed. Finally, in the third part, a review on innovative and peculiar investigation and monitoring techniques will be illustrated. The collected results can shed new light on future perspectives for the Civil Engineering sector, sector that has to be ready for facing the challenges of preservation, restoration and/or replacement of the existing infrastructural constructions, worldwide.

English Language Use in Malaysian Government and Private Civil Engineering Workplaces

Employers in the engineering sector require certain standard of English proficiency among their employees as the language is widely used for numerous job scopes. In order to understand the current demand of the civil engineering industry on the use of the English language in the workplace, this study was conducted on 20 undergraduates of the Civil and Environmental Engineering Faculty, Universiti Tun Hussein Onn Malaysia who undertook the industrial training. Based on focus group discussions, the participants learned and shared significant use of English language through their industrial training experience. The findings of the study highlighted the activities that were conducted in English for speaking, listening, reading and writing including the language skills. In addition, the amount of time spent on each activity in English was also identified in understanding the importance of English language in the civil engineering sector. The findings of the study are vital in making informed decisions for the design and development of appropriate English language courses for present and future civil engineering students.

Effects of Organic Matter on Physical Properties of Dredged Marine Sediments

Dredged sediment, listed as waste according to European classification, is available in significant quantities. With the announced shortage of standard materials to supply civil engineering sector (specifically road construction domain), the beneficial use of these wastes could lead to better management of waste and optimize the use of standard materials. Dredged sediments consist of a mineral phase, an organic phase (in various forms) and a liquid phase (generally water). However, the presence of organic matter (OM) in sediment, even in small amounts, can affect its physical properties. The main objective of this study is to investigate the effects of the OM content on physical properties of dredged sediments. The physical parameters studied are considered as a key parameter in the field of road construction. To undertake this study, a specific procedure for samples preparation was developed. This procedure allows undertaking tests on samples ranging from 2.5 to 15% in terms of organic matter content. The results on the prospected properties show that the material classification in the field of road construction is almost unaffected.

2nd International Conference on Sustainable Development in Civil, Urban and Transportation Engineering (CUTE 2018)

PrefaceSustainable development is actually an important topic which needs the attention of the society. The civil engineering is figured as one of the most impacting domains on the environment because of numerous problems such as the energy consumption, the CO2 emission and the natural resource depletion. Alternative solutions have been searched during the last decades to reduce environmental impacts of the civil engineering sector. Different approaches have been proposed: reducing the energy consumption by using low-embodied energy materials (“eco-materials”); developing the energy-efficient buildings with high thermal performance, with renewable energy integrations (solar, wind, geothermal, etc.), or by using the eco-architecture principles to optimize the energy consumption of the buildings. Today, sustainable development in civil engineering is not still restrained at a building scale but the city scale should be considered: the transport of the occupants between their residence and their work, the energy loss in the energy distribution network, etc.In this context, the 2nd International Conference on Sustainable Development in Civil, Urban and Transportation Engineering (CUTE 2018) is organized at Ton Duc Thang University, Ho Chi Minh City, from 17 to 19 April 2018. This conference is organized by Ton Duc Thang University (Vietnam) in cooperation with Université Savoie Mont Blanc (France), Hasselt University (Belgium), Technical University of Ostrava (Czech), Wrocław University of Technology (Poland) and University of Trieste (Italy). This is the second edition after the first conference which was organized in 2016. The main scope of CUTE 2018 conference is to propose an exchange platform for different approaches which can contribute to the sustainability of the civil engineering sector: investigations on sustainable materials and structures; intelligent principles in architecture design; sustainable solutions in transportation and urban planning.The host organization Ton Duc Thang University is gratefully acknowledged for the administrative and logistical support. The co-organizer universities are thanked for their cooperation and support.The sponsors of the conference are gratefully acknowledged for their financial supports.The organizers would like also to thank Honorary Chairs, Conference Chairs, International Scientific Committee, and Local Organizing Committee.EditorsQuoc-Bao BUI, Radim CAJKA, Minh-Tung TRAN, Tu-Anh TRINH Ansar-Ul-Haque YASAR, Geert WETS, Monika WOLOSZYN

Experimental Study on Ready-Mix Concrete: Case Study

Ready-mix concrete (RMC) in Tunisia is becoming more and more in demand in the civil engineering sector thanks to its qualities of handling in the fresh state and resistance in the hardened state, this composite material must respect the quality-price ratio. A RMC with a minimal cost is the object of our work. This research is part of the opening of higher education on professional life, where we optimized the formulation of a RMC. This work has 3 axes. In the first place the resources in building materials were characterized, namely various samples of sand, gravel, cement and water. Subsequently, the adjuvant-cement ratio (A/C) was optimized. Finally, the workability of the concrete as well as its mechanical aptitude at various ages 7, 14 and 28 days were characterized. These examinations have resulted in an appropriate formulation for any type of resource that varies according to the provenance of the quarries (gravel and sand), the effect of the plasticizer-water reducer is found for a very interesting A/C ratio, the mechanical tests for different ages are also conclusive.

Experimental Study on Ready-Mix Concrete: Case Study

Ready-mix concrete (RMC) in Tunisia is becoming more and more in demand in the civil engineering sector thanks to its qualities of handling in the fresh state and resistance in the hardened state, this composite material must respect the quality-price ratio. A RMC with a minimal cost is the object of our work. This research is part of the opening of higher education on professional life, where we optimized the formulation of a RMC. This work has 3 axes. In the first place the resources in building materials were characterized, namely various samples of sand, gravel, cement and water. Subsequently, the adjuvant-cement ratio (A/C) was optimized. Finally, the workability of the concrete as well as its mechanical aptitude at various ages 7, 14 and 28 days were characterized. These examinations have resulted in an appropriate formulation for any type of resource that varies according to the provenance of the quarries (gravel and sand), the effect of the plasticizer-water reducer is found for a very interesting A/C ratio, the mechanical tests for different ages are also conclusive.

The smart city: challenges for the civil engineering sector

In the twenty-first century, engineers are being tasked with solving ever more complex and subtle societal challenges – from climate change to unprecedented urbanisation that is materially affecting the lives of many urban populations. As engineers become ever more interdisciplinary and the boundaries of disciplines soften, they need to reflect as a community as to the appropriateness of the engineering paradigm to address these needs. Currently the engineering community is pointing to the digital technologies and the ‘smart city’ as a deliverer of efficiency and resilience without fully acknowledging the intricate sociopolitical context in which it is situated. This paper explores four key challenges that the (civil) engineering sector must contend with if it is to harness appropriately the potential of digital technologies while maintaining an ethical and productive foundation on which cities can thrive, including (a) embracing complexity, (b) the smart city and social justice, (c) financing the smart city and (d) engineering education.

How to Align the University Curricula with the Market Demands by Developing Employability Skills in the Civil Engineering Sector

The purpose of the research is to discover which employability skills may be developed by students from technical universities in order to meet market demands. Since graduates from technical universities face unemployment or over qualification for vacant jobs, we presumed that there is a misalignment between employers’ expectations concerning graduates’ skills and what they really get from school. Therefore, we conceived a questionnaire to see the demands of the business environment regarding graduates’ technical and professional skills. After analyzing the data, we proposed an interdisciplinary module system, where the mentors coming from the companies involved in the study teach voluntary or optional courses and applications in the domains where they have expertise. We used the employability skills model to find that mix of competencies that may help graduates find jobs in their field of knowledge. This innovative method serves universities, students and companies as well: the prestige of a university is quantified by the experts delivered into the labor market; companies will have well prepared employees in their specific area, with less costs; students will find jobs which will match their expectations, giving them motivation to perform. The limitation of the present research is that the study refers only to the Civil Engineering specialization of the Technical University Cluj-Napoca Romania.

Elaborating the History of Our Cementing Societies: An in-Use Stock Perspective.

Modern cities and societies are built fundamentally based on cement and concrete. The global cement production has risen sharply in the past decades due largely to urbanization and construction. Here we deployed a top-down dynamic material flow analysis (MFA) model to quantify the historical development of cement in-use stocks in residential, nonresidential, and civil engineering sectors of all world countries. We found that global cement production spreads unevenly among 184 countries, with China dominating the global production and consumption after the 1990s. Nearly all countries have shown an increasing trend of per capita cement in-use stock in the past century. The present per capita cement in-use stocks vary from 10 to 40 tonnes in major industrialized and transiting countries and are below 10 tonnes in developing countries. Evolutionary modes identified from historical patterns suggest that per capita in-use cement stock growth generally complies with an S-shape curve and relates closely to affluence and urbanization of a country, but more in-depth and bottom-up investigations are needed to better understand socioeconomic drivers behind stock growth. These identified in-use stock patterns can help us better estimate future demand of cement, explore strategies for emissions reduction in the cement industry, and inform CO2 uptake potentials of cement based products and infrastructure in service.

Distributed Humidity Sensing in PMMA Optical Fibers at 500 nm and 650 nm Wavelengths.

Distributed measurement of humidity is a sought-after capability for various fields of application, especially in the civil engineering and structural health monitoring sectors. This article presents a method for distributed humidity sensing along polymethyl methacrylate (PMMA) polymer optical fibers (POFs) by analyzing wavelength-dependent Rayleigh backscattering and attenuation characteristics at 500 nm and 650 nm wavelengths. Spatially resolved humidity sensing is obtained from backscatter traces of a dual-wavelength optical time domain reflectometer (OTDR). Backscatter dependence, attenuation dependence as well as the fiber length change are characterized as functions of relative humidity. Cross-sensitivity effects are discussed and quantified. The evaluation of the humidity-dependent backscatter effects at the two wavelength measurements allows for distributed and unambiguous measurement of relative humidity. The technique can be readily employed with low-cost standard polymer optical fibers and commercial OTDR devices.

A Study of Information Exchange for Architect & Engineer BIM Design under Low Impact Development Method

Collaboration of each division and BIM data continuity have been discussed continuously along with the introduction of the BIM design method in the construction sector and there is an increasing demand for design data analysis and simulation rather than simple design modeling. However, difficulties regarding data exchange using different software from different divisions in BIM design arose early in the implementation stage of BIM. Thus, designs have been conducted based only on the exchange between shape information and partial attributes. As a result of suggesting the data exchange method for design collaboration of BIM design in the civil engineering sector and simulating the analysis process with application of Low Impact Development (LID) in BIM design, smooth collaboration was maintained along with continuity of data between BIM design software and BIM-based analysis was subsequently carried out.

STRESS DISTRIBUTION OF SECONDARY BENDING IN SINGLE-LAP BOLTED JOINTS WITH DISSIMILAR JOINING PLATES AND PLATE TYPES

Single-lap joints are an important class of bolted joint in the aerospace and civil engineering sectors. This type of joint is preferred as it can reduce weight and hence help to optimize fuel efficiency. However, bolted single-lap joints exhibit secondary bending due to eccentricity of the applied loads. Flexural of plates during tensile loading alters the contact regions in the single-lap joint significantly, resulting in more non-linear behaviour and a stress gradient across the plate thickness. 3-D bolted single-lap joint were modelled in ABAQUS CAE incorporating the effect of the bolt tension from application of a tightening torque. Current 3-D model used elastic properties based on smeared-out properties, the effect of joint construction is considered further by examining the stress in a composite-composite joint and comparing with a composite-steel joint. In a related investigation the effect of varying composite thickness in the composite-steel joints is also studied.