Abstract: Large-scale construction of transport infrastructure inevitably includes the construction of new bridges. During the design process, many assumptions and simplifications are taken into account. Therefore, the verification of the structural response of new bridges is necessary. One of the possible tests of structural response is a proof-load test which can detect certain problems of investigated structures. The paper introduces numerical and experimental analysis of the new bridge, which is located on Slovak Highway D1, section Hricovske Podhradie – Lietavska Lucka. The verified bridge is a four-span continuous structure with a total length of 129.4 m. The bridge is a representative of typical precast girder bridges adopted for construction of Slovak highways. The superstructure consists of eight post-tensioned precast I-beams. During a load test, predicted structural response was verified to check for any unusual behaviour. Finally, recorded data was summarised and report was distributed to all subcontractors and bridge owner. This information may help in further bridge management program. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: This paper presents a numerical analysis of the piled-raft foundation (PRF) based on the actual behavior of supporting piles. The raft was modeled as a thin plate, while the piles were modeled as springs in different ways. This research also aims to propose an analytical model of piles based on actual behavior at fieldwork. The results proved that the structural behavior of raft member can be improved through utilizing the actual behavior of supporting piles. When the piles were modeled as non-linear stiffness springs, settlements and bending stresses of raft foundation were reduce marginally as compared with those obtained from piles with linear stiffness springs. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: Corrugated steel-plate girders are used as structural elements in many applications because of their properties, cutouts are always provided in these plate elements to enable inspection and servicing. This study presents an experimental and analytical study to investigate the efficiency of a steel-plate girder with corrugated webs (GCWs) and flat webs (GFWs) having cutouts under shear loading. In this study, we investigated the influence of some important parameters on the girders’ load-bearing capacity. The experimental program was conducted on six full-scale plate girders, which have been tested under central load at mid-span. The analysis was conducted using ANSYS V20 to perform a nonlinear technique for the determination of the ultimate load of the tested girders. Finally, experimental and finite element model were used to define the ratio of increasing carrying capacity in plate girder with flat and corrugated web, having cutout under shear loading. The ultimate strength, failure mechanism, and load-deflection curves from the experimental and analytical study show that the shear capacity of the girder with corrugated web girders extends loads by 22 % compared with the flat web. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: The increasing amount of energy consumed by the operation of buildings results in an increasing environmental burden. This has a direct impact on the innovation of renewable energy technology and its application in building industry. In accordance with the requirements of the “Europe 2020 Strategy” and “Europe 2030 Project”, the long-term goal is to achieve the maximum use of renewable energy sources in the buildings´ operation. One of the solutions is the building-integrated photovoltaic power plant. The paper analyses efficiency and incorporation of photovoltaic (PV) systems into the roofs and perimeter walls. PV systems are a renewable energy source used in the construction of zero energy buildings producing minimal environmental pollution. Semi-transparent building-integrated photovoltaics (BIPV) are one of the technologies that have the potential to increase the building´s energy efficiency as well as aesthetically complete the building´s design. The paper deals with material characteristics of PV panels in terms of the fire risk and definition of the fire hazardous area that arises during their combustion. It is focused on the incorporation of various types of PV technology into the facades and roofs, structural and material solutions of fire-dividing structures to which PV systems are fastened considering their location in the fire hazardous area. Based on the external fire simulations, conclusions in this paper bring the optimal position of PV systems in the building envelope in relation to fire open areas, fire lines and fire hazardous areas. The safety of firefighters during the intervention also depends on the position of PV systems. The case study presented in this paper uses a model solution to give the optimal position of PV systems in the building envelope considering the fire safety. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: Several elements contribute to the environmental effect of building construction, and many stakeholders share responsibility for these issues. Architects and engineers have a considerable interest in the design of the materials and building methods because they are vital in the creation of a design. The environmental effect of various building construction materials should be evaluated to select environmentally friendly building materials. The environmental effect of life cycle of a material comprises not only the energy used in its production but also emissions released into the environment at each stage of production. Embodied energy is one way of measuring construction and recycling environmental impact and the effectiveness of CO2 emissions. The use of indigenous and local construction materials together with energy-saving and environmentally friendly alternatives, including different forms, construction, and management techniques, reduces needless spending by cutting down on construction expenses. This study focuses on developing a comprehensive and integrated approach to environmental sustainability and cost control in low-rise building construction in Saudi Arabia and some other Arab countries by using alternative construction and management techniques and environmentally friendly and energy-efficient innovative materials. Multiple design alternatives, which utilize appropriate cost effective building materials, consider the physical environment, utilize methods of industrialization, and incorporate cost effective construction techniques, are discussed. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: The aim of this research is to predict foundation settlement resting on peat soil layer using a numerical analysis software Plaxis 2D ver. 2020. The study area located at Kafr Saad Domiat province at extreme north east Nile Delta, Egypt. Peat soil is known to be the worst foundation materials because of its compressibility and low bearing capacity. The studied building was five stories founded on a rigid raft. The foundation depth was at 1.5 m and the net pressure on soil was 50 kN/m2. The soil profile consists of soft clay layer from ground surface to depth of 3m followed by a layer of peat soil of thickness 1m, the final layer was soft to very soft clay layer till end of boring at 15 m depth. The ground water table was is at depth of 1.5m. The settlement of building was observed and recorded every 15 days up to 3 years. By comparing real field settlement observation values with that obtained by using finite element software it was concluded that the software predicted the real field settlement values. Also, to validate the results obtained by finite element software it was compared to values obtained using analytical method. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: The paper deals with the process of environmental risk assessment from exposure to noise from tram traffic. As part of the monitoring of the acoustic situation, measurements of sound pressure levels A were made and evaluated. The survey confirmed the existence of an acoustic risk in the form of a disturbing wailing sound when a tram vehicle passes through a directional curve with a radius of less than 50m. In addition to causing annoyance, the tonal variation of sound above 65 dB causes frostiness, cardiovascular, psychological and auditory problems, thereby damaging the health of people living and moving around the transport routes. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: Insufficient resilience of the natural environment is one of the many problems with the foundation of linear structures, and one of the ways to solve the foundation of a linear structure is the stabilization of soils. Fine-grained soils are problematic for traffic construction. The properties of clay soils change due to climatic conditions. They swell and become plastic in the presence of water, shrink in dry conditions, increase in volume, and freeze due to frost. Improving the properties of fine-grained soils with lime is a suitable solution to the problem in traffic construction. The purpose of soil improvement is to modify soil properties such as creating soil without cavities and gaps, increasing shear strength, reduce compressibility and permeability, the soil must be able to transfer the load without further settling (or unnatural compression). Soil improvement can be defined as an intervention in the natural geological environment or artificially built earth structures (embankments, notches), the purpose of which is to increase the resistance of the subsoil, achieve even settlement of the structure or object, accelerate consolidation, optimally build earth structures, etc. We can encounter the stabilization of the subsoil in all types of constructions, but most often in line constructions and water management construction. In our article, we focus on the effects of soil treatment with lime. The treated soil was F8 (CH) clay with high plasticity. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: A promising substitute for regular concrete is geopolymer concrete. Engineering mechanical parameters of geopolymer concrete, including compressive strength, are frequently measured in the laboratory or in-situ via experimental destructive tests, which calls for a significant quantity of raw materials, a longer time to prepare the samples, and expensive machinery. Thus, to evaluate compressive strength, non-destructive testing is preferred. Therefore, the objective of this research is to develop an artificial neural network model based on the results of destructive and non-destructive tests to assess the compressive strength of geopolymer concrete without needing further destructive tests. According to the artificial neural network analysis developed in this study, the compressive strength of geopolymer concrete can be predicted rather accurately by combining the results of the non-destructive with R2 of 0.9286. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: Recycling demolition waste materials as construction materials offers environmental as well as economic benefits by protecting virgin materials and reducing overall costs of project. This paper presents an experimental investigation on flexural behavior of reinforced concrete beams made with coarse aggregate fully 100 % or partially 50 % replaced by crushed concrete or crushed bricks as waste materials in full or half depth of beams. Nine beams are tested over a simply supported span, one with full natural aggregate as reference and the others with waste aggregate in different ratios and depths (four with crushed concrete and four with crushed bricks). Results show that the structural behavior of beams with waste aggregates is similar to the reference beam with strength reduction of 3 – 20 %. Crushed concrete beams show higher strength and stiffer behavior (in general) than crushed bricks. Also, increasing replacement ratio from 50 % to 100 % or replacement depth from half to full reduced strength by about 10 % only which encourage utilizing maximum quantity of waste construction materials in concrete structures. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: In this study, the stabilization process is introduced to a clayey expansive soil collected in southern Sweden. The tests examined strength parameters of expansive soil stabilized by different binders using combination of both traditional binders (cement and lime) and alternative materials (slag Merit 5000, fly ash from SCA Lilla Edet and fly ash from coal combustion, ISO certified). The practical goal was to find a binder mixture that is optimized for soil stabilization with respect to technical properties of stabilizing agent as an inert ballast material. The strength of soil stabilized by various binders was examined by velocity of the P-waves propagating through specimens. The results show that introducing slag Merit 5000 as an admixture to cement and lime is an effective approach in enhancing strength properties in weak soil, which increases bearing capacity of soil for planned construction works. The results also shown that a mixture of lime and bio ash yields a better effect in the stabilization of a clay. Soil stabilized with cement, cement/slag and lime/slag becomes resistant to freeze-thaw cycles, which is crucial for construction of roads and building foundations. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: In this study we determined the effect of variations in composition and particle size of Red Sand (RS) grains on the quality of concrete. Concrete was prepared as cubes of 15 cm3 with a composition of cement, sand and gravel in a ratio 1:2:3 and water to cement ratio of 0.5. Variations of RS (fine aggregate) composition are 0 %, 5 %, 10 %, 15 %, 20 % of the weight and red sand grain particle size were prepared as 80 mesh, 100 mesh, 120 mesh. Mechanical properties of the maximum concrete pressure strength test at a composition of 5 % along with a decrease in the size of the red sand grain size of 100 mesh and 120 mesh RS 100-5 and RS 120-5 with pressure forces of 35.4 MPa, and 35.5 MPa, respectively. On the other hand, the red sand with 80 mesh grain size have maximum pressure force in a composition 10 % RS 80-10 is 34.6 MPa. It is considered the addition of red sand fine aggregate has an impact on improving the quality of concrete. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: The asphalt-concrete pavement is an essential component of the bridge deck. Its stress characteristics are different from the general pavement structure. This research employs finite element technology (ANSYS) to model a three-span bridge and pavement layer in order to ascertain the stress distribution and provide a deeper knowledge of the mechanical properties of the pavement layer on concrete bridge decks. The effects of varying the thickness and stiffness of the deck pavement on the stress distribution in its different layers were investigated. Stress absorption is increased as the stiffness of the deck layers increases, and with increases in pavement thickness, stress on pavement layers decreases. The response of deck pavement under moving load, both under full bonding and sliding conditions, was simulated to determine stress distribution. By comparing the response under the full bonding and sliding conditions, it was found that stress induced on layers during sliding is high as compared to the full bonding condition; pavement layers will be prone to failure if sliding occurs between layers. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: Limestone wastes have accumulated in large quantities in countries all over the world. To reduce this materials this work is presented. The goal of this paper is to study the influence of limestone powder on the physical and mechanical of fired clay bricks. It is as replacement of clay, varying the limestone content 5, 10, 15 and 20 wt %. The water / soil ratio is constant 0.3. Three stages of firing are presented to achieve the maximum temperature. The first one is 300 °C and the second one is 600 °C and the last one is 900 °C. Results for the physical properties are showed an increasing of water absorption of clay brick specimens with the limestone content increased, in addition the efflorescence is increased. However, the density and firing shrinkage are decreased with limestone quantity. For the mechanical properties, the results indicate that the clay brick specimens with higher limestone 20 %, showed a decrease in compressive strength and flexural bending strength. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: Most of the railway lines in Slovakia were built in the second half of the 19th century, or until 1918 (the establishment of Czechoslovakia). Except for the post-World War II period, when approximately 71 % of the Slovak lines had to be renewed, limited funds have been spent on repair and reconstruction works on the lines located in the Slovak territory [1]. Nowadays, there is an effort to modernize the main railway lines but also to revamp the local lines. This is also a case of the line section Poltár - Utekáč, where in the near future a sleeper, which is in very poor technical condition, will be replaced by a Y-type sleeper. On this occasion, the impact of the new structure on the noise emission from the sleeper should also be assessed. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: This present research work mainly focusses on an investigation of the workability and strength properties of lightweight aggregates, particularly Palm oil shell and pumice aggregate, used in the production of concrete with (PA) and (POS), which were substituted for conventional Hard Broken Stone (HBG) coarse aggregate. Through the use of lightweight aggregate (POS and PA) in place of some of the coarse aggregate, the properties of a lightweight concrete M30 have been concentrated in this experimental study. The lab tests that were conducted include the compaction factor test, Schmidt Hammer test (rebound hammer test), and compressive strength. A total of 108 numbers of cube specimen were employed of size 2400 kg/m3. As part of a parametric study, the total number of cube specimens was divided into two groups according to various percentages: palm oil shell and pumice aggregate. In order to cast the cube specimens, dry weight of coarse aggregate was substituted for 0, 10 %, 20 %, 30 %, 40 %, and 50 % of POS and PA lightweight aggregate, respectively. A total of 9 cube specimens were cast and tested for 3, 7, and 28 days after successful curing in order to obtain accurate results. Average values were obtained from the test program and are shown in the corresponding Tables. Slump, compaction factor, rebound hammer compressive strength, and compressive strength values with different amounts of light aggregate were used to assess how well concrete performed when coarse aggregate was partially replaced with light aggregate. The test findings revealed that when the amount of conventional aggregates substituted by POS and PA increased, the slump test, compaction factor test, and strength of the lightweight aggregate concrete (LWAC) rapidly diminished. With an increase in the amount of aggregates replaced by POS and PA, the LWAC’s absorption has gradually increased as water. It is stated at the outset that the POS has shown to perform better than the PA when construction is done using structural lightweight concrete. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: This study investigated the implementation of Special Truss Moment Frames (STMF) X-braced type in accordance with the recommendations of the National Earthquake Hazards Reduction Program (NEHRP), 1997:2000 and Indonesian National Standards (SNI) 1726 where it is stated that the STMF may only be used up to a maximum building height of 48 m (160 feet) for Seismic Design Category of D. The analyses compared the seismic response of apartment buildings using STMF system with different height: 44 m (11 stories), 48 m (12 stories), and 52 m (13 stories). The nonlinear behaviors were investigated through a series of nonlinear time history and pushover analyses, including the inelastic response of the structural components, top-roof displacement, drift ratio, and ductility. The structural modeling and the selection of steel sections were performed in SAP 2000 based on SNI 1726 code, considering that the structure was built on medium soil in Aceh region. Seismic performance was examined through a series of pushover and nonlinear time history analysis (NLTHA) using three scaled accelerogram: Elcentro 1940, Northridge 1994 and Kobe 1995 records. The results of the study show that in case of STMF structure with the height of 52 m (higher than the maximum height of STMF structure stated in the codes), the seismic performance of the structure was excellent and met the requirements. Axial plasticization occurred only in X-braces, not followed by the formation of plastic hinges at the ends of the ductile segments. Meanwhile, the other structural components remained elastic. This indicates that the structure can still be used after the earthquake, by replacing only the X-braced components. The drift ratio met the requirements and the roof displacements behavior was asymptotic, indicating that there is no residual horizontal displacement of the building after the seismic loads occurred. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: Coarse-grained soils are a type of soil frequently found in civil engineering projects, and their mechanical characterization still presents a real challenge. They are composed by elements of different dimensions (from a few microns to tens of centimeters), and can be of very varied nature (clay, sand, gravel, pebbles, etc.). The mechanical characterization of coarse-grained soils is very difficult because of the presence of large elements. In order to be able to characterize them in the laboratory by means of conventional size devices, it is very important to study the influence of significant parameters on the mechanical behavior of coarse-grained soils (the volume fraction, particle size distribution and spread, consolidation level and initial state of the matrix), using the large-sized triaxial testing device. In this paper, we will propose a methodology for evaluating the mechanical characteristics of coarse-grained soils based on soil granulometric reconstruction procedures. The method we have named GALA is based on the use of polynomial correlations between the strength increase due to inclusions and the volume fraction fv and the particle spread (dmin/dmax) of inclusions. We were able to apply this new method to a natural soil. The results showed the relevance of our method. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: The purpose of the work is revolved around presenting a literature review applied to wave-structure interactions. During this literature review, three types of breakwaters are presented: Bottom submerged breakwater, submerged plate, and seawalls breakwaters. Further, a numerical method used recently to study wave-structure interactions is presented. Furthermore, a simple analytical model is illustrated. Next, an experimental technique then also is depicted. For more details, this review will focus clearly on submerged bottom breakwater in discussion section for the reason of the importance of this breakwater for many hydrodynamic applications. Finally, valuable remarks will be deducted in the conclusion section. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
Abstract: The identification of risks in construction projects gives advance indications of the potential risks that may occur during project planning, construction or management. Therefore, identifying those risks and preparing the necessary plans to respond to them is a key detail for the success of the project from its failure. The projects implemented in the manner of a Build Operate Transfer (BOT) contract are accompanied by many risks due to the multiplicity of parties and the multiplicity of their responsibilities, as well as the size of those projects because they are usually associated with infrastructure projects. The aim of this research is to identify the most prominent risks in BOT contracts and the planned response against each risk. The adopted methodology is through conducting interviews and a closed questionnaire (included 77 out of 100 respondents), and the adoption of statistical analysis through the SPSS program and the scale of relative importance.The relative importance index technique was used to rank the risks according to their importance and discuss the reasons for their classification. The results showed a list of the most important risks that would be generated if the BOT contract was applied to transportation projects in Iraq, as well as the appropriate planned response to each risk based on historical information for previous BOT projects. PubDate: Mon, 07 Nov 2022 00:00:00 GMT
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