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This paper aims to present a research finding that establishes a regression model between ultrasonic pulse velocity (UPV) tests and actual strength of high performance concrete (HPC).

In this study, a total of 270 cube samples were made from six different mix proportions. The mixes were grouped in two series that consist of nominal maximum aggregate sizes of 10 mm (A₁₀) and 19 mm (A₁₉). Silica fume were used as mineral admixtures at 5 percent, 10 percent and 15 percent of cement in both series. UPV tests were conducted for each of the specimens, followed by destructive strength tests. The tests were carried out for concrete at different ages of between three to 56 days. The destructive test results were used as the true strength of the mixes and the UPV test results were used as strength estimation.

Concrete strength correlations between UPV and destructive tests were analysed for each mix proportions and in each series. These correlations are presented in the form of regression equations that displays standard error of between ±2.4 to ±5.7 MPa regardless of mix for the concrete in series A₁₀. Similarly, in series A₁₉ concrete, standard errors of between ±3.2 to ±6.7 MPa were found. Strength prediction models using UPV for high performance concrete are proposed. The models have overall correlation coefficients above 0.80 for all the mixes.

There are no standard relationships that had been established for high performance concrete strength with UPV test methods. The proposed relationship can be used for concrete strength estimation that is normally required in building or structural assessment, especially with the present trend of constructing modern structures using high performance concrete.

The purpose of this study is to present a conceptual model that comprises the four phases of an inter-organizational mentoring (IOM) process.

This study used a focus group of 19 expert coordinators on IOM programs who met once at the Basque College of Economists. The session was recorded and notes were taken and distributed to all participants.

Based on the focus group, the authors developed a four-phase model of IOM. The phases this conceptual model proposes for IOM are awakening, transcendence, organizational bond and maturity.

These four phases should help mentors to guide mentees in the completion of an effective IOM process. This model is a re-conceptualization from the traditional mentoring phases, as the nature of the mentoring process is different. However, getting to understand the phases of IOM will enlighten the understanding of this phenomenon that is a growing option for managers in their career development as IOM helps managers to acquire skills and competencies.

This work contributes to the comprehension of this new form of alternative mentoring, clarifying for mentees and mentors, what process they are going to follow. Additionally, it provides clear criteria for inter-organizational program coordinators on how to organize these kinds of programs. In the opinion of the authors, this paper is original because it provides an in-depth understanding of IOM, which is an HRD technique that has barely been studied to date.

The changing nature of work dynamics demands that managers keep up-to-date in skills, knowledge, and competencies. Besides, nowadays these professionals need to understand the business beyond the frontiers of their own organizations. This phenomenon has led to new forms of alternative mentoring for managers and entrepreneurs, as companies battle for talent in a globalized way. Professional associations, consultancy firms, and other agents are starting to offer mentoring programs in which the mentor and mentee often belong to different organizations or take place within a group.

The purpose of this study is to present a conceptual model for alternative mentoring for managers. This model is a new approach to mentoring, and it will try to clarify some of the bases of a phenomenon that is increasingly present in the managerial field.

The paper also suggests some advantages of alternative mentoring when compared to traditional mentoring.

This paper contributes to a better understanding of new forms of alternative mentoring while providing practitioners in the field with a better understanding of key issues for alternative mentoring.

There are multiple questionnaires in the literature that try to gather university students’ perception about sustainable development (SD), but they are mainly focused on determining the students’ knowledge and attitude about sustainability. As the existing questionnaires did not fit the type of analysis that is intended to carry out, a new questionnaire was developed, adapted to the aims and context (engineering students) of the pretended study. The questionnaire contains two scales; one to determine the level of insertion of sustainability and the other to measure the importance that students give in their training process to the three dimensions of sustainability: economic, environmental and social. This new instrument requires a validation process to ensure its content – validity, reliability and clarity. The aim of this paper is to describe the validation process.

This paper shows the validation process of a questionnaire designed ad hoc to measure the students’ perception on SD inclusion level in three current engineering degrees, at the Engineering School of Bilbao (EIB) that belongs to the University of the Basque Country (UPV/EHU). The questionnaire validation process was conducted in three stages: experts on the subject provided their advice to ensure the study objectives, a small number of students contributed to clarify the statement of the questions, and thus, to increase the reliability of the questionnaire and finally, a larger number of students completed the survey to analyse the internal consistency of the two scales in the questionnaire with the Cronbach’s alpha test.

As a result of the entire validation process, an appropriate scale has been obtained to measure the importance that students give to the three dimensions of sustainability, economic, environmental and social, and to the sustainability overall. Furthermore, an appropriate scale to measure the insertion level of sustainability in engineering studies has been developed. However, the insertion scale needs a revision in the items of social and economic dimension to be valid to conduct disaggregated studies by dimensions.

The surveys published in the literature try to determine the knowledge and attitude that students have regarding SD. However, this new questionnaire, whose validation process is described in this paper, aims to know how engineering students of the EIB perceive the level of insertion of SD in their academic programs, from a frequency perspective, and the importance they give to it, both personally and professionally, given to the analysis a holistic perspective. Thus, the questionnaire can be used by higher education institutions to design strategies for inserting SD in engineering studies.

The purpose of this paper is to investigate the effect of elevated temperature on mechanical and physical properties of concrete specimens obtained by substituting the river sand with copper slag (CS) at proportions of 25%, 50%, 75% and 100%. The specimens were heated in an electric furnace up to 100, 200, 300, 400, 500 and 600 C and kept at these temperatures for 2 h duration. After the specimens were cooled in the furnace, mass loss, ultrasonic pulse velocity (UPV), compressive strength, split tensile strength (STS), flexural strength (FS) and modulus of elasticity (MOE) values were determined. No spalling occurred in the specimens after subjected to elevated temperature. The surface cracks were observed only in specimens exposed to 600 C. The maximum reduction in compressive strength and STS at 600C is 50.3% and 36.39% for referral mix (NC), 18% and 16% for specimens with 100% CS (MCS4). The reduction in MOE of specimens is observed to be high as copper slag content increases with increasing temperature. Scanning electron microscopy (SEM) studies are carried out to examine the changes in micro-structures of specimens after exposed to elevated temperatures.

After casting of concrete specimens, it is cured for 28 days. After attainment of 28 days age, the concrete specimens is taken out from the curing tank and allowed to dry for 2 days to remove any moisture content in the specimens to prevent explosive spalling during the time of heating. The prepared concrete specimen is subjected to temperatures of 100^°C, 200^°C, 300^°C, 400^°C, 500^°C and 600^°C up to 2 h duration. The physical test, mechanical test and SEM studies are carried out after cooling of specimens to room temperature (RT). The quality of concrete specimens is measured by conducting UPV test after cooling to RT.

The post-thermal strength properties of concrete specimens with copper slag contents are higher than referral mix concrete. The reduction of MOE of concrete specimens is more with incremental in copper slag content with increase in temperatures. Furthermore, the quality of concrete specimens is ranging from “good to medium” up to 500C temperatures based on UPV test.

In this research work, the natural sand is fully replaced with copper slag materials in the concrete mixes. The post-thermal strength properties like residual compressive strength, residual STS, residual FS and residual MOE is higher than referral mix after subjected to elevated temperature conditions. Higher density and toughness properties of copper slag materials will contribute to concrete strength. The effect of elevated temperature is more on MOE of concrete specimens having higher copper slag contents when comparing to specimens compressive strength.

The paper aims to examine the concept of architectural design communication (ADC) for updating design studio dynamics in architectural education during the Covid-19 pandemic. Within this perspective, the changing and transforming contents of architectural education, the thinking, representation and production mediums are examined through the determined components of ADC. There are five components in the study, which are (1) Effective Language Use, (2) Effective use of Handcrafts, (3) Effective Technical Drawing Knowledge, (4) Effective Architectural Software Knowledge and (5) Outputs.

The research method is based on qualitative and quantitative methods; a survey study is applied and the comparative results are evaluated with the path analysis method. The students in the Department of Architecture of two universities have been selected as the target audience. Case study 1 survey is applied to Altinbas University (AU) and Case study 2 survey is applied to Universitat Politecnica de Valencia (UPV) students during the COVID-19 pandemic; ‘19-‘20 spring term, online education.

As a result, two-path analysis diagrams are produced for two universities, and a comparative analysis is presented to reveal the relationships of the selected ADC components.

This paper fulfills an identified need to study how ADC can be developed in online education platforms.

The purpose of this paper is to analyze the potential for implementing Sustainable Development Goals (SDGs) into the civil engineering bachelor degree in the School of Civil Engineering at Universitat Politècnica de València (Spain).

All the 2019/2020 course syllabi were analyzed to diagnose at which extent each subject within the program curriculum contributes to achieving the different SDGs.

The results show a promising starting point as 75% of the courses address or have potential to address targets covering the 2030 Agenda. This paper also presents actions launched by the School of Civil Engineering to boost the SDGs into the civil engineering curriculum.

This paper presents a rigorous and systematic method that can be carried out in different bachelor degrees to find the subjects that have the potential to incorporate the SDGs into their program. This paper also presents actions launched by the Civil Engineering School to boost the SDGs into the civil engineering curriculum.

This article aims to present the differences in implementation between individual mentoring programs (IMPs) and group mentoring programs (GMPs).

This exploratory study used semi-structured interviews with 16 experts: mentoring program (MP) coordinators, consultants and mentors. During the interviews, the steps in implementing a mentoring program were reviewed and discussed by practitioners.

Based on the interviews and contrasting with the proposed implementation model, the authors compared IMPs and GMPs. The results highlight the role of the GMP coordinators, especially in the selection of mentors, mentees and generating resources that favor the beneficial effects of group dynamics on mentoring processes.

This model for implementing MPs and the differences identified between IMPs and GMPs provide practical help to program coordinators (PCs) and mentors to deploy MPs by highlighting the relevant aspects.

Mentoring is a Human Resource Development (HRD) technique whose implementation at the program level needs further deepening for practitioners. This is the first work that emphasizes the differences to be considered in the design and implementation of MPs by taking the individual or group dimension of mentoring.

Present work deals with the partial substitution of cement by waste demolished concrete powder (WDP) for reducing the carbon footprints of concrete.

Control specimens and the specimens with 20% WDP as fractional substitute of cement were prepared. The waste powder was thermally activated at 825 °C prior to its use in the mix. The prepared specimens were evaluated in terms of density, workability, mechanical strength, Ultrasonic pulse velocity (UPV) and rebound hammer (RH).

The results showed that with the substitution, the workability of the mix increased, while the density decreased. A decrement within a 20% limit was found in compressive strength. The UPV and RH results were closely linked to the other results as mentioned above.

The study deals with only M15 concrete and the substitution level of only 20% as a baseline.

The concrete containing 20% WDP is lightweight and more workable. Moreover, its strength at 28 days is 14 MPa, only 1 MPa lesser than the characteristic strength.

The WDP can be recycled and the dumping in landfills can be reduced. This is an important effort towards the decarbonation of concrete.

Previous literature indicates that the WDP has been frequently used as a partial replacement of aggregates. However, some traces of secondary hydration were also reported. This work considers the effect of partial substitution of cement by the WDP.

City planning and construction have embraced circular economy principles, converting them into various indicators. Particularly in the European context, the question “what architecture for circularity?” is answered with policies focusing on techniques, materials and disassembling construction. This paper analyzes a new approach to sustainable design and explores the concept of Km0 architecture. The objective is to demonstrate the design strategies of a contemporary architecture based on local resources and knowledge, an architecture that works with the shortest possible loop in circularity, i.e. with the cycle that consumes the least amount of energy.

The paper presents two ways of understanding sustainability in architecture: the first as a result of policies and the second associated with the design and innovative-based New European Bauhaus initiative. Within the scope of this last understanding, the authors analyze three cases on the Spanish Mediterranean coast that have recently received media attention and prominence. The selection responds to a specific climate adaption through a certain typological and functional diversity of the works.

The studied cases exhibit a more equitable and cost-effective circularity based on the time factor, have long life-cycle designs and serve as repositories of cultural identity. Km0 architecture reduces emissions using local resources and mitigates environmental conditions by combining traditional and modern design strategies.

This paper fulfills an identified need to study the local understandings of the built environment that would ensure a more fair and inclusive European green transformation.