OPTIMIZATION OF THE FORMWORK RENTAL COST USING THE NIF METHOD TAKING INTO ACCOUNT THE VARIATION OF THE CROSS-SECTION OF THE MONOLITHIC ELEMENT

Purpose: The aim of the work is to determine the optimal value of the cost of renting formwork for monolithic works, assuming a variable cross-section of the formwork elements. Design/methodology/approach: The article attempts to analyze the optimization costs of leasing system formworks using the author's research method NIF (no idle formwork). It is an extension of the classic parallel-stream methods - with continuous use of production means (no idle) and with uninterrupted work on the work front (no wait). For the purposes of empirical research, selected structural elements of a sports hall building with a monolithic "foot-column" structure were used. Findings: The implementation of the proposed NIF method proved that it allows for the selection of the numerical composition of the work team and the division of the work front into elementary plots, finding the optimal team work plan and implementation scenario in the set of admissible solutions, limited by the implementation deadline or cost budget. Research limitations/implications: The essence of calculating the rental of system forms is to determine the required time of their stay on the work front, during assembly, technological standstill (the process of binding the concrete mix) and dismantling. The calculation of the costs of traditional forms, apart from the time of their assembly and dismantling, during which the costs of human work (labour) are incurred, treats the above principle in a different way: wood formwork material, purchased as a non-renewable resource, is treated in it at the purchase price - with standard recovery, and not at the cost of labour. Practical implications: Construction formwork for monolithic works, due to its technological specificity, is divided into traditional – made of sawn wood, and system – supplied in the form of unified elements. Social implications: System formwork forms for monolithic works, as their price-determining component, are cost-intensive equipment units, hence the appropriate selection of their quantity and determination of the lease period on the construction site is a very important issue, affecting the profitability of these works. Originality/value: The innovative element of the work is the use of the proprietary NIF method, which determines the optimal level of construction formwork lease costs.