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Enhancing the strength of fly ash (FA)-based geopolymer by increasing the alkaline activator content is a costly and unsustainable technique. Therefore, this work was designed to reduce the activator by employing the pressured catalysis (PC) technique, coupled with the use of minerals that have filler and occupying effects. The main objective was to enhance the strength of the mix with a lower alkaline-to-precursor (A/P) ratio and create a sustainable, load-bearing building block from it. Initially, the compressive strength of the FA-based geopolymer was investigated experimentally by varying sodium silicate to sodium hydroxide and A/P ratios with ambient and hot curing. Afterward, PC was applied to the optimized proportion of constituents, and a significant increase in strength (9.6 to 20.0 Mpa) was observed at a 0.25 A/P ratio. By adding clay and dune sand (DS), the compressive strength was 19.5 and 40.4 Mpa at an A/P of 0.25 and 0.16, respectively. The strength gain mechanism was evaluated at the molecular and micro levels by conducting FTIR and SEM analyses. The environmental and economic indices and strength indicated the high sustainability of DS-based geopolymers compared to analogous blocks. The environmental and economic benefits of 23.9% reduced CO2 emissions and 24.2% less cost were provided by the DS-based block compared to the FA–clay-based block. A DS-based geopolymer obtains strength at a low A/P due to its occupying effect and results in sustainable building blocks. [ABSTRACT FROM AUTHOR]

Purpose: This paper focuses on knowledge storage, knowledge accessibility and the associated challenges with these processes in an interorganizational project. For this purpose, the context of the Orange Line (OL) metro train project in Pakistan is examined, where multiple organizations were involved. Design/methodology/approach: This study adopts an exploratory single case study approach. The empirical data comprise semi-structured interviews and archival documents. Thematic analysis is used for analyzing the data. Findings: The distinct findings include (1) the use of knowledge storage systems, such as manual storage systems, electronic storage systems and assigning a dedicated resource; (2) that knowledge accessibility occurs at different levels within the organization (including intradepartmental and interdepartmental levels) as well as at interorganizational levels and (3) the challenges, such as misuse of knowledge, time pressures, confidentiality of sensitive knowledge, government regulations and the reliance on human memory, which are associated with knowledge storage and knowledge accessibility. Based on the findings, an integrative framework of the interplay between knowledge storage, knowledge accessibility and challenges is proposed. Originality/value: This paper contributes to the literature on resource-based theory by examining knowledge storage and accessibility in an interorganizational project. [ABSTRACT FROM AUTHOR]