Ensuring high quality and efficiency of the worksin the process of constructing the tunnels of in-situ concrete

• Main Author: Ginzburg Aleksandr Vladimirovich
• Format: Article
• Language: English
• Published: Moscow State University of Civil Engineering (MGSU) 2014-01-01
• Series: Vestnik MGSU
• Subjects: quality of concrete; concrete; formwork; concrete pouring; self-compacting concrete; concrete curing; tunnels; underground; technological regulations
• Online Access: http://vestnikmgsu.ru/files/archive/issues/2014/1/ru/12.pdf

In the article the author describes the importance of the technological regulations development in the process of constructing various transport constructions: tunnels, subways, bridges and other important objects. In the article the peculiarities of the technological regulations development are fully taken into account; the dependence of the depth of their development and the quality of the concrete constructions, as well as the speed of the objects of transport infrastructure construction, including the examples of building the road tunnels in Moscow. The course of their development is shown with account for the main provisions, which should be included in technological regulations in order to ensure the most complete coverage of the issues arising in engineering, laboratory and Supervisory structure in the process of performing the works. The author proposes new effective materials and technologies of works. In particular, sufficient attention is paid to self-compacting concrete — a new type of concrete, which is able to flow and compact under its own weight, completely filling the formwork even in case of dense reinforcement, while maintaining the homogeneity and having no seals. The application experience of concrete self-sealing in the construction of the metro showed that labor costs for the concrete mixture sealing were 5-6 times reduced, and the speed of laying the concrete increased 2-3 times. When laying self-compacting concrete high-quality surfaces are formed, which do not require additional costs to bring them to the design parameters. In addition, the work shows the parameters of the technological processes and sets various types of works sequence: the article describes the features of formwork, placement and curing of the concrete in terms of year-round construction, shows the importance of thermo physical calculations of concrete hardening and the efficiency of using self-sealing concrete. Sufficient attention is also paid to the methods of quality assurance and to the methods of preventing cracking of various structural elements of a construction, as well as to the safety requirements and ensuring proper protection of the environment.