bluuebunny/crossref_metadata_2025 huggingface dataset:
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: February 2025

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.
ADOPTING NON-CONVENTIONAL MATERIALS IN AFFORDABLE HOUSING DELIVERY
Authors: Omuh Ignatius , Tunji-Olayeni Patience , Ojelabi Rapheal , Afolabi Adedeji , Erinle Yimika
Published: February 2025

The second greatest human need is shelter and this indicates the necessity for everyone to be housed. Adequate housing provision reduces a host of other risk that the sustainable development goals are expected to reduce or even eliminate. However, due to policies, rapid population growth, rural-urban migration, housing provision for the homeless populace fall short. This paper highlights the prospects and problems of using non-conventional materials for low cost or affordable housing provision. The non-conventional materials investigated included earthworm cast as partial replacement of cement, stabilized earth bricks, bamboo, ash from waste incineration. A survey research was designed, and 200 questionnaires were distributed to both professionals and end users of housing. The findings showed that funding was a major obstacle to affordable housing provision, but this could be improved by employing non-conventional sustainable materials. The findings also showed that thought there was inadequate funding, lack of awareness of some of these materials were critical to the utilization of these materials. It was recommended that the potential users be sensitized to promote sustainable construction practices.
STUDENTS' HOUSING SATISFACTION IN PRIVATE HIGHER INSTITUTIONS
Authors: Aghimien Douglas , Aigbavboa Clinton , Adama Joshua , Thwala Wellington
Published: February 2025

Student housing is essential to the attainment of quality education, most especially in higher institutions were students come from far distance to study. While research abounds on happenings with regards to student housing in public higher institutions, there is a paucity of information on this situation within the private higher institutions. This study, therefore, presents the result of an investigation of the satisfaction of students with housing facilities in private higher institutions in Nigeria. The study adopted a survey design and quantitative data were gathered through the use of a questionnaire administered to 216 students selected through stratified random sampling. The students' residence satisfaction was assessed from the physical, and social/management stands. Data gathered were analysed using percentage, mean score and Mann-Whitney U-Test. The study revealed that on a general level, while private institution students are more satisfied with the social and management characteristics of the residence than the physical characteristics. The study observed that although overall satisfaction is derived, there is still adequate room for improvement in order to deliver better housing for students. The outcome of this study provides a possible direction for the management of private higher institutions in improving their students' housing delivery in order to achieve higher students' satisfaction.
IMPACT OF CONCRETE MATERIAL INPUTS ON PERFORMANCE OF CONTINUOUSLY REINFORCED CONCRETE PAVEMENT
Authors: Sabih Gauhar , Tarefder Rafiqul Q.
Published: February 2025

Continuously reinforced concrete pavement (CRCP) is increasingly being used in the United States based on its longer service life with minimal maintenance. CRCP provides excellent performance for heavily loaded traffic volume, if designed and constructed properly. The performance of CRCP is evaluated based on punch-outs and pavement roughness according to the Pavement ME (mechanistic-empirical) Design procedure which is the state-of-the-art pavement design tool. Design of CRCP is dependent on various factors including traffic, climate, material inputs and pavement geometry. This study focuses on evaluating the effects of concrete mechanical and thermal properties and traffic volume on CRCP performance. CRCP design simulations were conducted using Pavement ME Design software version 2.3 to evaluate the effects of material input data on CRCP performance and it was observed that there is significant difference between the performance predictions with time series data in comparison to the default data. The impact of material inputs is more significant on punch-outs distress as compared to the pavement roughness. This necessitates the importance of lab tested material inputs for accurate design of CRCP. The impact of traffic volume on CRCP performance was also evaluated and it was found that with increase in traffic volume, the pavement distresses increases and the performance decreases.
DEVELOPMENT OF A DECISION MAKING TOOL FOR PAVEMENT MAINTENANCE MANAGEMENT UNDER SUSTAINABILITY CRITERIA
Authors: Espinoza-Valarezo Pedro , García-Segura Tatiana , Montalbán-Domingo Laura , Pellicer Eugenio
Published: February 2025

This paper focuses on solving the problem of budget allocation for the pavement maintenance management of an urban road network. To do this, a decision-making tool is developed. The tool is based on a quantitative valuation of six sustainable criteria to obtain a priority ranking. The relative weights are calibrated with the aim of obtaining a higher benefit-cost ratio to a horizon of 4 years. The tool is applied to a sample of Valencia's urban road network. The work concludes that decision-making based on sustainable criteria increases the ratio benefit-cost in 53%, compared with the plan based only on the condition of the pavement, which is typical in management agencies lacking an assessment tool. The application of the tool to an urban road network that differs in conditions with the sample analyzed must be preceded by a calibration similar to the one raised, in order to define the optimal scenario in relative weights.
CAUSES OF DEVIATIONS IN PROJECT EXECUTION AND THEIR EFFECTS
Authors: Müller Florian , Tupi Alexander , Heck Detlef
Published: February 2025

Over the past few years the German and Austrian construction industries have been confronted with increasing complexity in projects, a situation, which has resulted in a significantly higher number of construction claims. The lack of an effective documentation system and a standardized claim management system has led to a growing number of disputes and legal cases. To develop a standardized claim management system, it is essential to understand and analyze deviations in the as-planned vs. the as-built occurring during project execution. A standardized system may assist in the quantification of impacts of different deviations and change procedures in future projects. This paper focuses on deviations and their effects occurring during project execution, as well as possible disputes arising from them. Further research is necessary in order to develop an effective standardized claim management system.
REACTIVE DEVALUATION AS A BARRIER AGAINST AMICABLE CONSTRUCTION DISPUTE SETTLEMENT
Authors: Li Keyao , Chow On Yi , Cheung Sai On
Published: February 2025

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.
A STUDY OF ENDOWMENT EFFECT IN CONSTRUCTION PROJECT DISPUTE RESOLUTION
Authors: Li Keyao , Ng Yui Hang , Cheung Sai On
Published: February 2025

It has been reported that the average dispute value (the additional entitlement included in the contract to resolve disputes) was US $84 million and average length of dispute (the period between the time a dispute is formalized and it is settled) was 14.6 months in Asia in the year of 2016 (Arcadis Global Construction Dispute Report 2017). These figures are not impressive in terms of the non-productive use of valuable resources. Endowment effect (EE), which was firstly coined by 2017 Nobel laureate in economics science professor Richard Thaler, is a behavioral phenomenon that people attribute more value to the things they own. EE would derail making rational decisions. This study explores the application of EE on disputants' behavior in construction project dispute resolution (CPDR). In this regard, four sources of EE in CPDR were identified. These are i) ownership, ii) loss aversion, iii) status quo bias and iv) bargaining habit.
THE INFLUENCE OF BAMBOO REINFORCEMENT AND ADDITION OF FIBERS ON HOLLOW BEAMS
Authors: Ananda Faisal , Saputra Hendra , Sukri Armada
Published: February 2025

The development of the artistic value of a building with reinforced concrete material continues to grow, one of which burrows the pipeline so as unexposed so that the condition of a building looks beautiful. This condition makes a weakening of the strength of concrete. As for the weakness of the concrete caused by a small crack due to deflection or the other anticipated by the addition of fiber one of the rebar tie wire (bendrat). Based on this condition, the beam testing was done with size by 150mm x 200mm x 1200mm with using one-point loading. Concrete mix design using SNI 03-2834-2000. The load obtained without fibers using the steel reinforcement by 12.9% greater than the use of bamboo reinforcement. This is because the tensile strength of bamboo is smaller than the tensile strength of iron. Likewise, on the beam that added fiber as much as by 2% on the bamboo reinforcement, there is a difference of loading is smaller than the steel reinforcement by 25%. The interesting result is found in the 0.5 inch diameter beam which has an increase in load with the initial crack conditions close to the same as the beam without a hole.
SCRAP TIRE RUBBER-BASED AGGREGATE IN LIGHTWEIGHT CONCRETE
Authors: Záleská Martina , Čítek David , Pavlíková Milena , Bazgier Vojtěch , Pavlík Zbyšek
Published: February 2025

Reusing rubber particles from used tires is good for the environment and, moreover, the world's population is becoming progressively conscious that a very high demand for natural resources is unsustainable. As the concrete industry consumes high amounts of natural resources, both for clinkering and gravel aggregate production, one must focus on its sustainability, considering environmental and economic issues. Therefore, reuse of waste tire rubber in concrete or in other composite materials is a logical solution for sustainable production of construction materials. Hence, the paper is aimed at the development and testing of lightweight concrete composed of a high volume of crushed waste tire rubber used as partial replacement of natural silica aggregate. In order to access the effect of incorporation waste tire rubber-based aggregate in concrete composition, reference concrete mix based on silica aggregate only is studied as well. The crushed waste tire rubber is characterized by its powder density, specific density, and particle size distribution. Specific attention is paid to thermal transport and storage properties of waste rubber that are examined in dependence on compaction time. For the developed lightweight concrete, mechanical, hygric, and thermal properties are tested. The tested lightweight concrete is found to be alternative and environmentally friendly construction material possessing improved thermal insulation function, interesting hygric parameters and sufficient mechanical resistance.
UTILIZATION OF SUPERABSORBENT POLYMERS IN PLASTERS FOR MODERATION OF INDOOR RELATIVE HUMIDITY LEVEL
Authors: Fořt Jan , Doleželová Magdaléna
Published: February 2025

Nowadays, the energy efficiency and moderation of indoor environment of buildings became important topic in the field of building physics. Moisture occurrence in building construction poses a significant task for building designers and material engineers. Among other factors, a high level of relative humidity has negative effect on the work efficiency and health of building inhabitants. The presented paper is aimed on the analysis of chosen superabsorbent polymers (SAPs) and its influence on properties of newly developed interior plasters. The identification of optimal ratio between superabsorbent polymers and plaster mixture from the point of view of the workability of fresh mixtures is done. Also, the effect of water/dry mixture ratio is studied according to enhanced absorption capability of SAPs. Specific attention is paid to hygric properties, the determination of apparent moisture diffusivity, water vapor resistance factor and estimation of sorption isotherms. Obtained results directly point to significant effect of SAP admixture on material properties of developed plasters. Namely, addition of up to 3 wt.% of SAPs shifts the water absorption coefficient almost ten-times, while the total open porosity is increased only about 20%. Such materials can be applied for the damped areas or places where increased water transport parameters play an important role for the efficient moisture removal.
POTENTIAL UTILIZATION OF GRANITE WASTE WITH METAKAOLIN IN SUSTAINABLE CONCRETE
Authors: Sharma Ravi K. , Gupta Trilok , Chouhan Digvijay S.
Published: February 2025

Cement production is a crucial factor responsible for climate change and recognized as major environmental challenge for humankind. It causes around 5% of global CO2 emissions resulting in lowering of air quality and human health. Production of cement is highly energy intensive process requiring consumption of depleting limited natural resources. Granite stone is famous for strength, elegance and durability. Enormous quantity of granite slurry waste is generated during processing of granite stone blocks, which adversely affect the fertility of land, environment and society. Metakaolin is an ultrafine pozzolonic and economical alternative to silica fume. It has positive influence on concrete properties because of filling effect and additional pozzolanic reaction. In this experimental investigation replacement level of both granite slurry waste and metakaolin are taken up to 10% as partial replacement of cement. Mechanical and durability properties of modified concrete have been evaluated. It has been shown that optimum replacement level of both materials enhances the compressive and flexural strength. Also, improvement in water permeability and resistance to acid attack has been observed. This study demonstrates that utilization of granite slurry waste and metakaolin as partial replacement of cement will reduce the consumption of cement, which will conserve the natural resource, reduces CO2 emission, energy demand and waste accumulation. Hence, the production of new composite concrete will be sustainable and advantageous to the environment and society.
STRENGTH PROPERTIES OF DURABLE CONCRETE MADE WITH VARIOUS ALTERNATIVE CEMENTITIOUS MATERIALS
Authors: Yoshitake Isamu , Inoue Shun , Miyamoto Keisuke , Yamato Koichiro
Published: February 2025

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.
VISIBLE TEST ON BUGHOLE GENERATION OF FLUIDITY CONCRETES FOR TUNNEL LINING
Authors: Yoshitake Isamu , Hieda Masahiro , Okamoto Kenta , Maeda Tomoyuki
Published: February 2025

Bughole (surface air-void) is a concern for surface quality though it rarely decreases strength properties of the concrete structure. In particular, sidewall of NATM tunnel lining which generally has negative angle is a significant concern in the bughole problem. To reduce the surface imperfection of concrete, the authors examined the bughole properties and discussed on construction methods in previous investigations. The present study focuses on the relation of bughole generation and concrete viscosity. A visible test of bughole generation was conducted using high and medium fluidity concretes in addition to the conventional concrete. Bughole distribution and properties were analyzed by the image analysis which was developed in our previous study. This paper reports the effect of concrete fluidity on decrease of bugholes on concrete surface. A remarkable observation in the experimental study is that number and area-ratio of bugholes increased with concrete viscosity while large voids can be decreased by using high/medium fluidity concrete.
USING ARABIC GUM IN PRODUCTION OF REFRACTORY BONDING MORTAR
Authors: Hasan Shatha , Eedan Osama , Azwz Katreen
Published: February 2025

Refractory bonding mortar is a specially-engineered blend consists of non-metallic materials that give the mortar unique heat-resistance and thermal characteristics for use in high-temperature applications. The goal of this study was to determine the performance of refractory mortar that produced from local raw materials in this study; Iraqi clays were utilized as raw materials while Arabic gum was used as adhesive materials. Three proportion mixes were applied, (96:4), (93:7), and (90:10) as (grog: kaolin binding material) and the burning temperatures for specimens were 1500°C. In the present research, some physical test such as the percentage of apparent porosity, bulk density, and specific heat are studied. Also, some mechanical properties such as compressive strength, binding strength, and dimensional stability are investigated. Finally, thermal conductivity and thermal shrinkage as thermal properties are also surveyed. All refractory bonding mortar produced in this study which has been used local materials have a good quality and it has all the characteristics of an economical product.
BEHAVIOR OF M 50 GRADE SELF-COMPACTING CONCRETE DEVELOPED USING PORTLAND SLAG CEMENT AND METAKAOLIN
Authors: Nalla Sravya , Maganti Janardhana , Pasla Dinakar
Published: February 2025

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.
EXPERIMENTAL ASSESSMENT OF TRC CYLINDRICAL TUBE-SHAPED UNITS
Authors: Donmez Didem , Gencoglu Mustafa , Donmez Ahmet Abdullah
Published: February 2025

The purpose of this study is to investigate the behavior of tube-shaped TRC ductility experimentally via monotonic loading. Ar-Glass and PVA as textile materials are used in the production of composite tube parts. These parts were tested in four and six layers and in different thicknesses. As a result of the mortar thickness, textile layers play the major role in ductility and strength. As the tube thickness increases, the strength increases, but the ductility decreases. However, ductility increases as the tube thickness decreases and the energy absorption increase by making the parts more flexible. This paper analyzes how much ductile the 10 cm long tube can be under pressure and tensile forces. The use of different textile materials, different thicknesses, and different numbers of textile layers has been examined. According to the test results, it is concluded that cylindrical tube shaped units produced by using PVA fabric material is more ductile than units produced by using Ar-Glass fabric material. Also, with the wall or slab elements or pipeline obtained by using these units, the structure system can be strengthened against earthquake loads.
MAGNETIC FIELD TREATED WATER INFLUENCE ON STRUCTURAL CONCRETE ELEMENTS: ENVIRONMENTAL ISSUES OF CONCERN
Authors: Ngene Ben , Bamigboye Gideon , Agomo Chidiebere , Eneh Kenechukwu , Olajide Olayinka
Published: February 2025

The impact of magnetized water on the strength properties of concrete calls for a holistic appraisal of its effect on the environment of production and use. In this study, the influence of the Magnetic Field Treated Water (MFTW) on the strength of concrete produced under various environments is considered. The work considered three environments of use of magnetized water in concrete with respect to partial replacement of fine aggregate with waste glass; quality of curing medium on mechanical properties of concrete and effect on the mechanical properties of self-compacting concrete. The three scenarios presented involved preparing and testing concrete cubes made with magnetized water, cement, fine (sand and glass) and coarse (granite) aggregates at various levels of combination and environment of curing. The concrete cubes were cured for 7, 14, 28, and 56 days and the strength and other parameters, such as slump and workability, were compared with conventional concrete in normal environment. It was observed that concrete under self-compacting concrete made with MFTW had a 9.1% increase in compressive strength than normal; for concrete made with clay brick powder and MFTW, both the workability and compressive strength was higher than normal. The magnetized water in concrete with waste glass as partial replacement had higher slump value and 24% increase in compressive strength than conventional concrete. MFTW therefore improves strength development of concrete.
MECHANICAL AND MICRO-STRUCTURE CHARACTERIZATION OF STEEL FIBER-REINFORCED GEOPOLYMER CONCRETE
Authors: Elkholy Said , El-Hassan Hilal
Published: February 2025

This paper aims to investigate the mechanical performance of steel fiber-reinforced geopolymer concrete made with fly ash and ground granulated blast furnace slag as blended aluminosilicate source material. To activate the binding phase, combinations of sodium silicate (SS) and sodium hydroxide (SH) solutions with three different molarities (8M, 10M, and 14M) were used. Steel fibers were added to the geopolymer concrete mix in varying proportions up to 3%, by volume. Constant binder, activator solution, and aggregate contents were adopted for all 13 mixes. Samples were cast and cured at ambient conditions for measuring the rheological and mechanical properties, including slump, modulus of elasticity, compressive strength, tensile splitting strength, and flexural strength. Experimental test results show that geopolymers made with higher molarity of SH were less workable but had improved mechanical performance. The effect of adding steel fibers on the mechanical performance was more apparent at an early age and in weaker geopolymer concretes. Additionally, scanning electron microscopy, differential scanning calorimetry, and Fourier transform infrared spectroscopy highlighted the co-existence of calcium aluminosilicate hydrate and sodium aluminosilicate hydrate gels.
NOVEL CONCRETE MIXTURE USING SILICA RICH AGGREGATES: WORKABILITY, STRENGTH AND MICROSTRUCTURAL PROPERTIES
Authors: Awoyera Paul , Akinmusuru Joseph , Ede Anthony , Jolayemi Joshua
Published: February 2025

The persistent reliance on traditional construction materials is of no gain to the future generation. The rate at which the natural aggregate sources are explored is alarming, and as a result, the threat of depletion of the natural materials has inspired interest in sustainable construction materials, focusing on construction and demolition wastes and local materials. In this study, an experimental insight on modified concrete, based on workability, strength and microstructural properties, is provided, in an attempt to ascertain the suitability of silica-rich aggregates (ceramic industry wastes and laterite) as a replacement for conventional fine and coarse aggregates. Various mix proportions were considered, and material batching was done by weight for concrete casting. The workability test, using slump, indicates that the flowability of the modified concrete mixes is achievable at a water-binder ratio of 0.6. The strength properties of the concrete increased with the increasing ceramic substitution for granite while increasing laterite content beyond 10% negates the strength gain by the concrete. A concrete mix containing 90% ceramic fine and 10% laterite, as fine aggregate, and 100% of cement and ceramic coarse, as binder and coarse aggregate, respectively, gave higher compressive strength (22.5 MPa), and split-tensile strength (3.6 MPa), and these results were found as comparable to the conventional concrete.
EFFECTS OF DIFFERENT SOURCES OF WATER ON THE PROPERTIES OF CONCRETE
Authors: Omuh Ignatius , Ojelabi Rapheal , Afolabi Adedeji , Tunji-Olayeni Patience , Obi Chukwuma , Mosaku Timothy
Published: February 2025

Water is vital to human existence and life can only be sustained by it. Concrete is a widely used construction material and water is an important part of its composition. Potable water is what is recommended for concrete works, but unfortunately, some places do not have access to this. Places that do not have access to potable water might have access to other water sources that might be used for concrete works. This study was undertaken to investigate the effects of water from different sources on concrete mechanical properties. This study evaluates the characteristics of concrete produced with river water, well water, and potable tap water. Compressive strength and Density, were used to evaluate the characteristics of concrete specimens of mix ratios 1:2:4 and 1: 1 1/2 :3 produced with water from the different sources. The results showed that concrete specimens produced with tap water had the highest mean compressive strength at 28 days. While well water had the lowest compressive strength, it was concluded that well water was not suitable for concrete works even though it is already being used on some sites that can’t access tap water.
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: February 2025

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.
THE EFFECT OF AGE ON THE COMPRESSIVE STRENGTH OF CONCRETE BY USING ULTRASONIC PULSE VELOCITY
Authors: Yousif Qadri Ahmed , Bedirhanoglu Idris , Aydin Mehmet Enver , Zebari Ziwar
Published: February 2025

In this study, the effect of age on the strength development of concrete was investigated. For this purpose, specimens casted with ready mix concrete for different grades of concrete were obtained from ready-mix concrete firms available in Diyarbakir city which is the one of the biggest cities of Turkey. A few sets with different grade of concrete cube specimens were used in the experimental work. Each set included over 40 specimens. For measuring concrete strength development, two different tests were used: ultrasonic pulse velocity testing (UPV) and uniaxial compressive strength testing. After UPV and compressive strength tests, strength development for early ages was evaluated and defined. The aim of this work is to define the path of strength development of certain grades of concrete used in the east regions of Turkey. Another aim of the work is to be able to determine concrete strength through non-destructive UPV tests. As a result, it was seen that concrete strength development for early ages is not linearly proportional to age. Further, UPV measurements can give information on the progress of concrete strength.
EFFECT OF INCORPORATING NANO ZEOLITE ON THE STRENGTH OF NATURAL POZZOLAN-BASED GEOPOLYMER CONCRETE
Authors: Rahman Muhammad Kalimur , Ibrahim Mohammed , Barry Mohammed Salihu , Al Khalifa Hassan
Published: February 2025

Natural pozzolan is a green and sustainable material, which has a strong potential for utilization in the geopolymer concrete. At room temperature, the development of strength in natural pozzolan based geopolymer concrete is fair, however, it is desirable, to have higher strength and to enhance the early age strength development. The effect of nano zeolite (NZ) as an additive to the mix by incorporating it at 3% and 5% by weight of natural pozzolan on the strength development and microstructural properties of natural pozzolan based geopolymer concrete mixes are presented. Scanning electron microscopy (SEM) was utilized to determine the morphology of the paste. The results indicated that 5% nanozeolite replacement resulted in superior strength and denser microstructure compared to other mixes. The addition of nanozeolite improved dissolution of source material in the alkaline activators and enhanced transformation of it to form polymeric compounds.
MICROSTRUCTURE INVESTIGATION OF SEAWATER VS. FRESHWATER CEMENT PASTES
Authors: Younis Adel , Ebead Usama , Suraneni Prannoy , Nanni Antonio
Published: February 2025

Recently, seawater has emerged as viable mixing water for concrete, especially in the case of non-reinforced concrete applications or with the use of non-corrosive reinforcement. Previous studies concerning seawater-mixed concrete mostly revealed an initial slight increase in its strength performance (i.e., till Day 14 following mixing), followed by a strength reduction of 7–15% (i.e., after 28 days or longer) as compared to the conventional freshwater-mixed concrete. With an attempt to explain such observations, this paper aims at comparing the microstructure of freshwater-and seawater-mixed cement pastes. Scanning electron microscopy was utilized to observe the microstructure of freshwater and seawater pastes at Days 3 and 28 following mixing. At Day 3, seawater paste was observed to have more densified microstructure as compared to that of the freshwater counterpart, resulting in relatively higher strength performance. At Day 28, the microstructure was almost similar for the two cement pastes. However, seawater paste was observed to have salt impurities as a result of seawater ions, which possibly cause a slightly lower strength performance as compared to the freshwater paste.
PREDICTION OF UNEVEN DISTRIBUTION OF SNOW LOAD BASED ON GENERALIZED REGRESSION NEURAL NETWORK
Authors: Ren Zhicheng , Zhang Qingwen
Published: February 2025

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.
FINITE STRAIN MEASUREMENT USING IMAGE ANALYSIS UNDER REVERSE SHEAR AFTER FORWARD SHEAR
Authors: Kato Yasuyuki
Published: February 2025

The purpose of this research is to investigate the progress of local deformation under finite deformation by using image analysis based on the Natural Strain theory. Since Natural Strain used in the image analysis can satisfy the addition law of strain on an identical line element and can remove the rigid body rotation from shearing strain component, it is an effective strain for representing stress and strain behavior under large deformation. Therefore, in this research, these features of Natural Strain theory will be incorporated into the method of image analysis. In the present study, using the test pieces made of high purity tough pitch copper, the local deformation occurring under large simple shear is investigated by comparing the strains in each element from the upper position to the middle position with the average strain in the gauge length. In order to investigate the progress of local deformation caused by differences of strain hardening in the material, the experiments are conducted under different deformation histories which are given by applying reverse shear after applying forward shear with different sizes. Consequently, it is revealed that if the value of plastic strain obtained by integrating over the whole deformation path is almost the same, the progress of local deformation is approximately the same even if the deformation path is different.
AN INVESTIGATION OF THE CONTRACTUAL ROADWAY SAFETY TERMS IN TRANSPORTATION PPP PROJECTS
Authors: Shang Luming , Abdel Aziz Ahmed M.
Published: February 2025

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.
GOVERNMENT ROLES IN PUBLIC-PRIVATE PARTNERSHIPS PROCUREMENT OF INFRASTRUCTURES: THEORETICAL APPROACH
Authors: Ojelabi Rapheal Abiodun , Fagbenle Olabosipo Ishola , Amusan Lekan Muritala , Afolabi Adedeji Olushola
Published: February 2025

Social and economic infrastructures provision has been the sole responsibility of the government in the time past. However, due to the geometric demand in human infrastructures needs, the government supply capacity has been constrained. The inability of the government to close the infrastructural gaps is due to the inequality in financial capacity and the financial worth of social and economic infrastructures. Despite the paucity of the fund required for infrastructures provisions in government, the need for social and economic infrastructures cannot wait due to its relevance in nation-building. The innovative approach to meeting the social and economic infrastructures is engineered through the adoption of a Public-Private Partnership (PPP) procurement option. The procurement option is a sure route through which infrastructural provision can be sustained. This paper reviews literature on Public-Private Partnership by buttressing on the expected roles of the government through the Governance theory concept.
AN ENGINEERING RELIABILITY ANALYSIS METHOD BASED ON ADAPTIVE METAMODELS
Authors: Wang Qian , Jarosch Erica , Fang Hongbing
Published: February 2025

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.
RESEARCH ON THE MEASURES AGAINST LARGE EARTHQUAKES AND TAKING REFUGE AT ONE'S OWN HOME
Authors: Hisagi Akie , Ishikawa Takashige
Published: February 2025

The possibility of a huge earthquake striking Tokyo in the future is high. In the event of such an earthquake, many people will face problems such as the inability to return to their homes, which will cause complete disorder and confusion in the city as it will be impossible for everyone to access emergency shelters. If buildings remain safe, it will be desirable for residents to take refuge at home. In this study, we investigated the disaster awareness of 461 residents in central Tokyo using an internet survey. Our results reveal that approximately 60% of residents expect to take refuge at their own homes. However, almost none of the respondents have emergency supplies such as water, food, and other daily necessities. This lack of preparedness could result in many people having to move to emergency shelters when disaster strikes. By analyzing these results, we aim to develop a method for avoiding confusion in the aftermath of a disaster and educate building residents on their needs and the preparatory actions they must take in such situations.
MODEL DISASTER PREVENTION LESSONS IN PRIMARY SCHOOL BASED ON DISASTER PREVENTION EDUCATION POLICIES
Authors: Imura Noriko , Ishikawa Takashige
Published: February 2025

This study deals with disaster mitigation education in primary schools and as a final goal aims to improve citizens’ capabilities to mitigate disaster situations in society. This report summarizes the current national policy on safety education in Japan and follow it up with a summarization of the Tokyo Metropolitan Government policy, which is based on the national policy. In addition, it compares Japan’s education policy with that of New Zealand. Analysis revealed the following three points. First, the content of safety education in Japanese primary schools consists of six fields (traffic safety, daily life safety, disaster safety, etc.). Just before, and after, the Great Tohoku Earthquake in 2011, the main educational content changed from daily life safety to disaster safety. Second, by focusing on lessons, it was found that the content of disaster safety was taught not as part of various subjects but largely during “homeroom activities”. Third, it became clear that the subject of earthquakes now accounts for half of the disaster prevention lesson contents in Japanese primary schools and has been included in disaster prevention lesson contents in all school grades.
CONCEPTUAL BIG DATA CASE STUDY TO IDENTIFYING RISKS OF NEW NUCLEAR TECHNOLOGIES
Authors: Yeon Jaeheum , Czarny Mark , Walewski John , Kang Julian
Published: February 2025

New technologies associated with nuclear power plants are being introduced regularly. However, many of the risks and uncertainties associated with these new nuclear technologies have yet to be identified. In this study, the risks related to newly-developed nuclear technologies were determined through an extensive review of the extant literature. A qualitative visual content analysis was selected as the research method employed to identify words repeatedly occurring in 147 journal articles. Through this conceptual “big data” approach, frequently mentioned words were identified using a co-occurrence map. The analysis results were then grouped into four categories: fuel resources, operational system designs, nuclear reactor cooling systems, and steam generators. Words used repeatedly to reference these four key categories were determined to also represent potential causes of risk factors. Many texts could be analyzed in a short period of time through the use of visual content analysis software. Frequently emphasized correlating words were then identified. This big data approach can also be applied to additional nuclear power practices to identify other uncertainties. Last, the limitations of a visual content analysis employed as a risk identification approach were revealed through this study.
DISPUTED RISKS IN CONSTRUCTION
Authors: Awwad Rita , Karam Joe
Published: February 2025

The construction industry is perceived as one of the most crucial fields in risk management studies due to its inherent risks and complexity. Despite the large amount of research presented in this area, experts still prefer relying on their own knowledge and experience to manage project risks. This approach leads to various disputes among construction stakeholders over the ownership of these risks and their mitigation. Such disputes normally affect the project’s goals in terms of budget and schedule. Many researchers have addressed risk factors in the construction field; however, none has tackled the disputed risks among construction parties. This research aims at identifying the different disputed risk factors among project stakeholders along with their respective mitigation strategy. It is based on an empirical questionnaire sent to construction practitioners with various expertise. An analysis of the results is conducted using descriptive statistics and one-on-one interviews. This research provides experts with a list of the most disputed risks in construction, along with their mitigation approach. In the end, construction parties will be able to meet the project’s goals and steer clear of any delay or cost overrun resulting from the occurrence of disputed risks.