Purpose. This paper presents the innovative scientifically-based method on efficiency evaluation of the building production management for contracting companies. Otimisation models are substantially aimed at reducing the influence of negative factors and increasing the quality indexes of the organisational process of construction production. Methodology. Methodological approaches of the organisational processes optimisation of construction production are based on the establishment of a well-defined interconnection between the units of the functional structure, the definition of strategies hierarchy of the contracting company.The correlation of duration t and cost c in building production, its influence on the economic appropriateness for projects realisation in civil engineering are analyzed. Findings. Using mathematical analysing methods for cumulative distribution function S(t,c) of two-dimensional random value of construction duration and cost, the basic principles are shown that allow to qualitatively and quantitatively determine the level of influence of the construction market external factors on the implementation of organisational processes in the construction industry, in which a large number of forming elements are involved. The implementation of this methodology permits to assess the real state of organisational processes system in building production, its stability, the degree of determinate indicators structuring in a single functional system, to generate an economic justification in complex. On basis of simulation modeling, efficiency of organisational processes system in building production S(t,c) was determined and graphically illustrated. Originality. The results of the present study demonstrate that it amounted to 58.08 % within the established limits of acceptable risk (LAR) between 0.35 and 0.65. Practical value. It has been shown an implementation practicability of using this methodology by contracting companies at decision-making stage for construction projects initiation with determinate indicators of duration Td and cost Cd. The creation of theoretical and methodological foundations for the development of structural efficiency evaluation algorithms for the organisation of construction production will allow to achieve for contractor companies the highest level of competitiveness in the market of construction services.

This paper argues that in the context of transformation from the linear to circular model of the economy, the issues of managing the flow of construction and demolition waste (C&DW) are becoming increasingly relevant, which is primarily due to the increase in prices for building materials, as well as resource saving and interest of stakeholders in the creation of eco-cities. The tools and methods to manage C&DW flows have been examined in the context of simultaneous ensuring the environmental and economic efficiency of the process. It is substantiated that the expediency of implementing the C&DW flow management process exists only within the framework of the system of integrated management of waste flows from construction and demolition of real estate in compliance with logistical principles and coverage of the interests of all stakeholders of the process. Tools, methods to forecast and plan C&DW volumes within IFMS have been proposed, which contributed to the construction of a model for forecasting the volume of C&DW formation and, therefore, determining the amount of total costs for the creation of appropriate technological capacities; the development of a model for assessing information risks in the process of logistics management of C&DW flows (based on solving the transport problem according to Kolmogorov's differentiated equations) and constructing an algorithm for its application, the introduction of which in practice will ensure the balancing of the interests of each stakeholder interested in the processing of C&DW; solving the problem of synthesis of reducing the cost of managing C&DW flows and reducing environmental pressure. In order to combine the goals of minimizing costs and minimizing environmental damage within the framework of SIWFM, a two-purpose dynamic optimization model is proposed, as well as restrictions on the possibility of its introduction and validation of this study's results. It is substantiated that the tools and methods of economic and mathematical modeling proposed in the current study could solve an important scientific and practical task to effectively manage C&DW flows