The study is devoted to identifying the main trends in the development of the theory of evaluating the effectiveness of investment and construction linear-extended projects, the implementation of which is carried out with the participation of public investments of different levels, as well as those of socio-economic importance for the construction region and Russia as a whole. Global informatization, penetrating into all spheres of human activity, determines the digital economy formation as an economic activity operating in the digital space. This means that digital material data is a key factor in production, processing of which in large volumes, compared to traditional forms of management, makes it possible to increase the economic activities efficiency. Methods of qualitative and quantitative risk assessment and accounting for the uncertainty of investment projects have been applied. In most theoretical directions, the preference is given to the use of the cost effectiveness criterion; methods of qualitative assessment and risk identification; introduction of modern digital methods of risk assessment and uncertainty accounting (Monte Carlo method, method of integral convolutions of numbers). There is no universal theoretical approach that reveals the investment process essence through the return on investment, which makes it possible to reliably assess the economic efficiency in construction ICP in the digital economy. It was revealed that the implementation of investment and construction projects (ICP) suggests the need to supplement the theoretical foundations, taking into account their specificity in terms of the effects taken into account, as well as uncertainty factors. The development of efficiency theory and, as a consequence, an increase in the basic data collection speed in the digital economy, as well as an increase in the reliability of efficiency estimates due to mathematical methods for quantifying risk and uncertainty. The implementation of investment and construction projects plays an important role in the transport industry.