"Вестник МГСУ"

Nikolaev railway depot is one of the first locomotive depots in Russia. It is a monument of cultural heritage, and it belongs to a group of buildings of the Leningrad Railroad Station in Moscow. The depot was designed by renowned architects K.A. Ton andR.A. Zhelyazevich in 1951. The depot building is round; it consists of 22 sections. The bearing structures of the building, its columns, arches and vaults are made of masonry. The depot building was remodeled several times, following changes in its intended use. Therefore, the original look of the building has lost its initial splendour. Now its structures are badly damaged, and the bearing capacity of its masonry columns and arches has changed for the worse. Its reconstruction will be accompanied by the restoration of its original exterior. Its reconstruction must be accompanied by the comprehensive monitoring of the stress-strain state of its surviving structures. The renovation must be based on the structural analysis of changes of its properties and damages. Currently, the engineering staff of our university is monitoring the strained state of the building to give advice in the course of its further restoration.

The paper considers civil engineering in retrospect. The paper presents the records of the two contracts that date back to 1837 and 1838. The contracts cover the two stages of construction of a famous church in Vozdvizhenskoe Village in the Moscow Province. These documents were stored in the Central Historic Archive, namely, in the collection of the town hall of Sergievskij Possad. These records of the two agreements in the collection of the brokers notes (or in other books of the same type) are of particular value, as the majority of authentic contracts have been lost. One of the contracts covers the organizational procedure and pre-construction works, while the other one covers the construction of the church. The first document gives the idea of environmental protection, employment of ecological technologies, and safe disposal and recycling of human biowaste in the course of dismantling of an old structure in Vozdvizhenskoe village. The second document that dates back to 1838 covers the sequence of construction works, starting from the foundation and ending with the arches, the types of building materials used, and peculiarities of stone masonry. The information recorded in the contract includes the names of the counterparties, day-to-day mode of life of seasonal workers, remuneration of labour and procedures that assure the quality of construction. This agreement makes it possible to outline the construction process that includes workers, bricklayers, the foreman, the contractor, the architect, and the customer. On the whole, both documents help us outline and assess some of the building practices of the 19th century. This issue is relevant nowadays, as our society has entered the phase of the market economy, while the experience accumulated by the past generations is of undeniable value.

Subject: multi-layer building envelope is the subject of the paper. Recently, in the context of energy conservation policies, the heat engineering requirements for enveloping structures of buildings and structures have significantly increased. At the same time, their moisture condition has a significant impact on the operational properties of materials of structures and on microclimate of rooms constrained by these structures. Research objectives: emphasize importance of the task of predicting the temperature and moisture condition of the walling at the stage of design and construction of building envelopes. In this paper, the temperature distributions in layered walls are analyzed. Materials and methods: to achieve the objectives, computational and experimental studies are conducted. By alternating (rearranging) layers and preserving the thermal resistance of the wall on the whole, we find the optimal alternation of layers that minimizes deviation of the maximum wall temperature from the average temperature. Results: for the optimal location of layers in the wall’s structure, the moisture penetration into the wall is minimal or absent altogether. This is possible if the heat-insulating layer is mounted on the outer surface of the structure. Conclusions: the obtained results of computational and experimental studies allow us to verify appropriateness of accounting for alternation of layers in multilayer structures. These calculations proved that the higher the average temperature level, the more energy-efficient the structure will be.

In the article the survey results of durability and crack resistance investigation of masonry are presented. The aim of the investigations is improving calculation methods of masonry and reinforced masonry. The relevancy of the problem is determined by the necessity of new efficient materials implementation. In accordance with scientific search methodology complex investigations were carried out, which includes gathering, analyzing and revising the existing data on the topic together with determining essential factors and their value rate. Within the framework of the investigations the features of masonry have been studied. The developed calculation method on the basis of the theory of resistance of anisotropic materials at the compression, which reflects the stress-strain state features and nature of destruction, allows to carry out an assessment of durability and crack resistance of the compressed members and structures made of masonry. The research results can be used at revising or updating the existing normative documents.

Results of the theoretical analysis of experimental diagrams of deformations of columns made of wood sawdust and concrete mixtures and of wood sawdust and gypsum mixtures exposed to uniaxial compression are provided in the paper.
The findings of the prototype testing include identification of the two areas of deformations: areas of elastic deformations and areas of intensive development of deformations. The first area of partial elastic deformations is characterized by the linear stress function, while the second area demonstrates that this relationship is nonlinear. Permanent deformations appear as of the startup of the loading process and disproportionate stress is demonstrated throughout the deformation process. However, in the first area (partial elastic deformations) residual deformations are so small that this area is considered as the area of "the area of incomplete elasticity".

Masonry is a complex multicomponent composite composed of dissimilar materials (brick / stone and mortar). The process of masonry deformation under load depends on the mechanical characteristics of the basic composite materials, as well as of the parameters belonging to the elements, which define the link between brick and mortar being the structural elements. The paper provides an analysis of the experimental study results of masonry behaviour in two-dimensional stress state at primary stresses of opposite signs; identifies the mechanisms of masonry failure that are in compliance with the conditions of stress state. The work shows the key role that structural elements play in the formation of masonry failure processes. On the basis of failure mechanisms educed from the experiments, there was developed a discrete model of masonry. The processes and the corresponding strength criteria, which play a key role in the implementation of plastic deformation phase, have been detected. It has been shown that the plastic deformation of masonry under biaxial stresses occurs in case of the physical linear behavior of the basic materials (brick and mortar). It has been also substantiated that the plastic properties of masonry under biaxial stresses are determined by the processes occurring at the contact interaction nodes between brick and mortar in bed and cross joints. The values of the plasticity coefficients for masonry depending on the mechanical properties of a brick, a mortar and adhesive strength in their interaction have been obtained basing on the results of the performed numerical investigations.