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Punching can trigger catastrophic failures in flat slabs because of its sudden nature resulting from exceeding the shear capacity of slabs. Effect of using recycled aggregate, as an environmental-friendly alternative to traditional RC structures, on punching behavior of these slabs was not sufficiently investigated in the literature. Hence, this paper aims to experimentally study the effect of using recycled coarse aggregate (RCA) on the punching shear capacity (PSC) of RC flat slabs. The RCA is produced by crushing of waste of concrete standard cubes obtained from compression tests.

A total of 12 slab-column connection specimens with different slab thicknesses (140, 160 and 200 mm) and different RCA percentages (0%, 30% and 70%) were prepared and tested under a central point load, to test its effect on the behavior of flat slabs. The punching failure loads of the tested specimens were compared with those obtained according to the provisions of different international building codes.

Compared with natural aggregate concrete, mixes with 30% and 70% RCA experienced reductions in the compressive that did not exceed 4% and 21%, while reductions of 4% and 13% were observed for the tensile strength, respectively. The increase in the amount of RCA reduced the PSC by 0%–7%, 0%–4% and 4%–10% for slabs with a thickness of 140, 160 and 200 mm, respectively. For slabs with punching shear reinforcement (PSR), ACI 318 provided the closest estimation for the PSC by 9%, whereas EURO 2 overestimated the PSC by 25% and ECP 203 underestimated the PSC by 41%.

The provided conclusions are obtained from the conducted experimental work where a constant W/C ratio, aggregate type and a maximum aggregate size of 19 mm for the RCA were adopted.

Enhancement in the behavior of flat slabs with various thicknesses and amounts of RCA because of introducing PSR is experimentally evaluated. The failure loads of the tested slabs with recycled and normal coarse aggregates were compared against different code provisions.

This paper aims to estimate the bearing capacity of a surface strip and circular footings lying on layered sand using numerical limit analysis.

Lower and upper bound limit analysis, as well as finite elements and second-order conic programming (SOCP), are used in this analysis. The yield criterion of Mohr-Coulomb is used to model soil behavior. Using this technique, stringent lower and upper bounds on ultimate bearing capacity can be achieved by assuming an associated flow law.

The obtained results indicate that the exact collapse load is typically being bracketed to within 6% about a mean of both the bounds. The obtained results are compared with the existing literature wherever applicable.

To the best of the authors’ knowledge, no study has used lower and upper bound limit analysis, as well as finite elements and SOCP, to estimate the bearing capacity of a surface strip and circular footings lying on layered sand.

This study is concerned with the dynamics of the internal communications at Netflix following the release of The Closer and the public debate that followed, testing Netflix's long-standing reputation for promoting diverse content and supporting a progressive organizational culture.

Using the circuit of culture (CoC) as a theoretical framework, this study applies a case study approach to analyze internal communication and strategic public relations in addressing this crisis.

This study's findings illustrate that by failing to interpret two of the five moments of the CoC, production and identity, Netflix negated the very values that constitute its brand. These findings have implications for how public relations' long-standing focus on two-way symmetrical communication is problematic, especially in the workplace.

The findings situate how the exertion of power within an organization, particularly in moments of identity and production, problematize the role of two-way symmetrical communication within an organization in crisis.

In recent years, additive manufacturing (AM) has started to be used for manufacturing real functional parts and assemblies for critical applications in aerospace, automotive, and machinery industries. Most complex or assembled parts require internal features (IF) such as holes, channels, slots, or guides for locational and mating requirements. Therefore, it is critical to understand and compare the structural and mechanical properties of additively manufactured and conventionally machined IFs.

In this study, mechanical and microstructural properties of Inconel 718 (Inc718) alloy internal features, manufactured either as-built with AM or machining of additively manufactured (AMed) part thereafter were investigated.

The results showed that the average ultimate tensile strength (UTS) of additively manufactured center internal feature (AM-IF) is almost analogous to the machined internal feature (M-IF). However, the yield strength of M-IF is greater than that of AM-IF due the greater surface roughness of the internal feature in AM-IF, which is deemed to surpass the effect of microstructure on the mechanical performance. The results of digital image correlation (DIC) analysis suggest that AM-IF and M-IF conditions have similar strain values under the same stress levels but the specimens with as built IF have a more locally ductile region around their IF, which is confirmed by hardness test results. But this does not change global elongation behavior. The microstructural evolution starting from as-built (AB) and heat-treated (HT) samples to specimens with IF are examined. The microstructure of HT specimens has bimodal grain structure with d phase while the AB specimens display a very fine dendritic microstructure with the presence of carbides. Although they both have close values, machined specimens have a higher frequency of finer grains based on SEM images.

It was shown that the concurrent creation of the IF during AM can provide a final part with a preserved ultimate tensile strength and elongation but a decreased yield strength. The variation in UTS of AM-IF increases due to the surface roughness near the internal feature as compared to smooth internal surfaces in M-IF. Hence, the outcomes of this study are believed to be valuable for the industry in terms of determining the appropriate production strategy of parts with IF using AM and postprocessing processes.

This paper presents the experimental and numerical results of the bending properties of low-height prestressed T-beams. The purpose is to study the bearing capacity, failure state and strain distribution of low-height prestressed T-beams.

First, two 13 m-long full-size test beams were fabricated with different positions of prestressed steel bundles in the span. The load–deflection curves and failure patterns of each test beam were obtained through static load tests. Secondly, the test data were used to validate the finite element model developed to simulate the flexural behavior of low-height prestressed T-beams. Finally, the influence of different parameters (the number of prestressed steel bundles, initial prestress and concrete strength grade) on the flexural performance of the test beams is studied by using a finite element model.

The test results show that when the distance of the prestressed steel beam from the bottom height of the test beam increases from 40 to 120 mm, the cracking load of the test beam decreases from 550.00 to 450.00 kN, reducing by 18.18%, and the ultimate load decreases from 1338.15 to 1227.66 kN, reducing by 8.26%, therefore, the increase of the height of the prestressed steel beam reduces the bearing capacity of the test beam. The numerical simulation results show that when the number of steel bundles increases from 2 to 9, the cracking load increases by 183.60%, the yield load increases by 117.71% and the ultimate load increases by 132.95%. Therefore, the increase in the number of prestressed steel bundles can increase the cracking load, yield load and ultimate load of the test beam. When the initial prestress is from 695 to 1,395 MPa, the cracking load increases by 69.20%, the yield load of the bottom reinforcement increases by 31.61% and the ultimate load increases by 3.97%. Therefore, increasing the initial prestress can increase the cracking load and yield load of the test beam, but it has little effect on the ultimate load. The strength grade of concrete increases from C30 to C80, the cracking load is about 455.00 kN, the yield load is about 850.00 kN and the ultimate load is increased by 4.90%. Therefore, the improvement in concrete strength grade has little influence on the bearing capacity of the test beam.

Based on the experimental study, the bearing capacity of low-height prestressed T-beams with different prestressed steel beam heights is calculated by finite element simulation, and the influence of different parameters on the bearing capacity is discussed. This method not only ensures the accuracy of bearing capacity assessment, but also does not require a large number of samples and has a certain economy. The study of prestressed low-height T-beams is of great significance for understanding the principle and application of prestressed technology. Research on the mechanical behavior and performance of low-height prestressed T beams can provide a scientific basis and technical support for the design and construction of prestressed concrete structures. In addition, the study of prestressed low-height T-beams can also provide a reference for the optimization design and construction of other structural types.

This paper aims to answer report how mentors who onboard newcomers to a high-stress social work organization can learn about their onboarding practice by treating onboarding as a wicked problem that escapes definitive formulation and final solutions.

The authors follow an action research approach with three iterations of learning about onboarding with mentors in a Danish social work organization struggling with an employee turnover exceeding 30%.

The authors unfold the authors’ emerging sensitivity to wickedity over the iterations of learning about onboarding with the mentors. As the authors foreground the wickedity of the authors onboarding in the last iteration, three lessons learned could be derived: it warrants the mentors’ continuous inquiry; opens inquiry into the ambivalence of mentoring; and convenes responsibility for inquiry to a community of mentors.

This study of problematic onboarding to high-stress social work shows the value of fore-grounding wickedity instead of hiding it with a positive framing. This wickedity rests on situated grounding and is only transferrable to other organizations with the utmost caution.

High-stress social work organizations without the capacity to systematically sustain best practices for onboarding may, instead, increase attention to the wickedity of onboarding as a motivation for continuous inquiry by a broader community of mentors.

To the best of the authors’ knowledge, this paper is the first to present an action research study of problem wickedity to motivate mentors’ inquiry into onboarding newcomers to high-stress social work.

The Quality Assurance Agency (QAA) for Higher Education in the UK focuses on maintaining, enhancing and standardising the quality of higher education. Of significant impact are the development of subject benchmark statements (SBS) by the QAA, which describe the type and content of study along with the academic standards expected of graduates in specific disciplines. Prior to 2022, the QAA did not have a SBS to which higher education policing programmes could be directly aligned.

Over 12-months, a SBS advisory group with representatives from higher education across England, Scotland, Wales and Northern Ireland, The College of Policing, QAA, Police Federation of England and Wales and policing, worked in partnership to harness their collective professional experience and knowledge to create the first UK SBS for policing. Post publication of the SBS, permission was sought and granted from both the College of Policing and QAA for members of the advisory group to reflect in an article on their experiences of collaborating and working in partnership to achieve the SBS.

There is great importance of creating a shared vision and mutual trust, developed through open facilitated discussions, with representatives championing their cause and developing a collaborative and partnership approach to completing the SBS.

A collaborative and partnership approach is essential in developing and recognising the academic discipline of policing. This necessarily requires the joint development of initiatives, one of which is the coming together of higher education institutions, PSRBs and practitioner groups to collaborate and design QAA benchmark statements.

The SBS advisory group has further driven forward the emergence of policing as a recognised academic discipline to benefit multiple stakeholders.

The SBS for policing is the first across the UK. The authors experiences can be used to assist others in their developments of similar subject specific benchmarking or academic quality standards.

This chapter shares the challenges that scholars experienced during the pandemic and their responses to them. We find that participants responded to complex work and home challenges through ethics of grit and perseverance. Offering a caution against grit mindsets, we argue that academics would benefit from opportunities to develop fuller forms of resilience. To do so, we recommend that higher education institutions co-construct locally and culturally relevant conceptualisations of resilience and enact trauma-informed practice to better support academic resilience in their faculties.

In this article, the author discusses works from the French Documentation Movement in the 1940s and 1950s with regard to how it formulates bibliographic classification systems as documents. Significant writings by Suzanne Briet, Éric de Grolier and Robert Pagès are analyzed in the light of current document-theoretical concepts and discussions.

Conceptual analysis.

The French Documentation Movement provided a rich intellectual environment in the late 1940s and early 1950s, resulting in original works on documents and the ways these may be represented bibliographically. These works display a variety of approaches from object-oriented description to notational concept-synthesis, and definitions of classification systems as isomorph documents at the center of politically informed critique of modern society.

The article brings together historical and conceptual elements in the analysis which have not previously been combined in Library and Information Science literature. In the analysis, the article discusses significant contributions to classification and document theory that hitherto have eluded attention from the wider international Library and Information Science research community. Through this, the article contributes to the currently ongoing conceptual discussion on documents and documentality.

The Central Bank of Nigeria (CBN) recently relaunched Nigeria’s cashless policy initiative which seeks to reduce financial crime and tax avoidance, decrease cash dependency, advance the adoption of digital financial services (DFS), decrease the risks to the payment system and foster financial inclusion. This study aims to identify the unique challenges of going cashless in Nigeria, particularly in terms of infrastructural, exclusionary and cost implications of the policy on the average citizens.

The author applies a doctrinal research methodology to identify and reflect on key challenges of the cashless policy from the economic, regulatory and transactional perspectives.

The cashless policy initiative in Nigeria heralds value for financial integrity, financial policy regulation and user convenience. The mode of introduction, however, ushers in significant challenges and hardly considers Nigeria’s inadequate payment infrastructure, persistent financial exclusion, low levels of financial and digital literacy and capability, high cost of using DFS and pervasive proclivity for cash. As Nigerians adjust albeit inconveniently to the policy, the CBN can ameliorate the hardship by strengthening the payment infrastructure, particularly for digital payments, fostering consumer trust by safeguarding user funds and enabling consumer preferences.

Research materials include the national regulator’s policy documents and newspaper articles that have not been published in formal reports but non-the-less adequately mirror the policy intention of the CBN and the lived experiences of Nigerians.

This study identifies the practical steps and regulatory measures that the CBN can take to improve acceptance and meaningful and sustainable adoption of the cashless policy by the majority of Nigerians.

The recommendations that are proffered provide some rich insights to inform regulatory direction for the CBN to seamlessly phase-in the cashless policy and consequently drive down financial exclusion in Nigeria.

This study contributes to the policy discussion around the introduction of the cashless Nigeria project. The doctrinal research method highlights the policy intentions of the regulator in juxtaposition with lived experiences of Nigerians. This study offers recommendations to bolster financial inclusion, stability and integrity.