Ссылка для цитирования этой статьи: Бокарев С.А., Кобелев К.В. Усиление железобетонных опор железнодорожных мостов полимерными композиционными материалами // Интернет-журнал «Транспортные сооружения», Том 3, №2 (2016) http://t-s.today/PDF/02TS216.pdf (доступ свободный). Загл. с экрана. Яз. рус., англ.

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The paper presents data on the prevalence and service life of solid piers of railroad bridges of the Russian Railways. The dynamics of solid pier damages, the development of normative documents on assessing their technical conditions and durability, and methods of assessing the residual life of bridge structures are shown herein. Information on the threshold values of failure is also given. The residual life of the intermediate masonry support is analyzed and estimated using two standard techniques. Their similarities and differences are determined and their limitations are compared. Proposals are made to clarify the damage parameters described in the current normative document for assessing the technical condition of railway structures. For statistical data processing in relation to bridge damages and prediction of their development, a model is proposed on the basis of semi- Markovian process. Possible data sources for constructing such a model are indicated. An alternative model for estimating the reliability of bridge structures is shown.

At present, more than four thousand metal bridge spans are in operation all over the Russian railway network. Through the years of operation, about thirty types of fatigue cracking were identified. The dynamics of the types Т-9 and Т-10 cracks formation has increased significantly in recent years. The formation and growth of fatigue cracking is influenced by such factors as residual welding stress, stress-strain state of the bridge structure, defects, damages, and non-observing the operation and maintenance standards, bridge location and bridge span structure. At present, neither measures nor repair are performed to prevent fatigue cracking not exceeding 20 mm in length. Only when a creak reaches a certain length, the regulatory documents require to drill a hole at a crack mouth in order to prevent its further development. The hole diameter should be equal approximately to the doubled wall thickness. In order to prevent further crack growth and cover the hole, a high-tensile bearing type bolt is fixed into it, creating a volume stress. As a rule, such a repair is not enough to stop the cracking process. The article suggests a number of measures based on induction heating that allows to prevent cracking (including forging reducing gaps between connecting plates and horizontal sheets in a truss), to carry out repair (crack mouth soldering) and reinforcement (fixing metal plates onto a wall with a hole).