75504 2712-8172 4 30 2012 1-71

RAR RUS 2-9 Peter the Great St. Petersburg Polytechnic University Bulatov Georgiy bulatov.spbgpu@gmail.com

29 Politechnicheskaya St., St. Petersburg, 195251, Russia

Peter the Great Saint Petersburg Polytechnic University Gatanov Dmitriy dmi2240@gmail.com

Polytechnicheskay, 29

Reliability of earth dams on compound base This article deals with the design of earth dams (estimating filter strength, compressibility and permeability of soils, studing of the stress-strain state, etc.) The authors look through a new, not previously discussed task of reliability of groundwater dams in extreme conditions like an influence of new and additional loads in the form of intense deformation of elongation and the base curvature. The dependences that allow determining the permissible values of deformations of ground dams earth surface on undermined territories are presented. The proposed method allows calculating the required parameters of structural and technological protection activities. In addition, the solution of such problems as predicting the behavior of the dam and its degree of reliability for a given expected deformation from external influence is found. The reliability forecasting of conventional dams, without undermining, can also be made. 10.5862/MCE.30.1 reliability of hydraulic structures cracking crack resistance surface undermining ground dam foundation deformation https://engstroy.spbstu.ru/article/2012.30.1/ 01.pdf

RAR RUS 10-16 Peter the Great Saint Petersburg Polytechnic University Balashov B. ksenbor@gmail.com

Polytechnicheskay, 29

Peter the Great Saint Petersburg Polytechnic University Belyaev Nikolay dnd@mail.ru

Polytechnicheskay, 29

Peter the Great Saint Petersburg Polytechnic University Mikhalenko E. ksenbor@gmail.com

Polytechnicheskay, 29

ZAO "GT Morstroy" Tazeyev T. Monitoring of fill dam constructed in Ust-Luga on soft foundation soils Improvement of fill dams sediment measuring methods and receiving long-term results of in-situ measurements and their analysis is relevant and have a great practical importance for the prediction of possible sediments and, consequently, to enhance the safety of objects on soft foundation soils. The object of this study was the dam as part of a complex for transshipment of liquefied petroleum gases in the commercial port of Ust-Luga. During the work monitoring of facilities was carried out in order to control the security status of hydraulic structures under construction and to evaluate their impact on the environment. The focus in the period of 2010 - 2011 years was given to geodetic control of sediment of the fill dam, which was built on soft foundation soils up to 20...25 m depth. 10.5862/MCE.30.2 monitoring safety dam rotten soils settling https://engstroy.spbstu.ru/article/2012.30.2/ 02.pdf

RAR RUS 17-24 Samara State University of Architecture and Civil Engineering Senitskiy Yuriy Senitskiy@mail.ru Samara State University of Architecture and Civil Engineering Kuzmin N. The oscillations of ship lock bottom The article deals with the dynamic characteristics of the ship lock. The accurate design relations intended to study the natural and forced vibrations of the bottom of the ship lock are provided. The degree of filling of the lock, as well as the added mass of water is considered. The various coupling conditions of the bottom and walls of buildings are taken into account. A concrete example of the calculation is given. An exact, in the framework of the adopted design scheme, solution of the problem of the own and forced vibrations of the bottom of the ship lock is found. The frequency of the first five tones of vibrations and the associated mass of liquid according to thickness of the structure and coupling conditions of the bottom and sides of the lock are analyzed. A significant effect of liquids on low-frequency part of the spectrum and the dynamic response of the bottom is determined. 10.5862/MCE.30.3 ship lock lock bottom bottom oscillations frequency added mass of fluid finite integral transformations https://engstroy.spbstu.ru/article/2012.30.3/ 03.pdf

RAR RUS 25-32 Peter the Great St. Petersburg Polytechnic University Badanin A. chinnab@mail.ru

St. Petersburg, Russia

Peter the Great Saint Petersburg Polytechnic University Evgeny Kolosov eskol@cef.spbstu.ru

29 Politechnicheskaya St., St. Petersburg, 195251, Russia

Determining the bearing capacity of soil foundation reinforced by geogrid The article deals with improving the construction properties of soils due to their reinforcement by geosynthetics, namely the geogrid. Geosynthetics have been widely used in the construction of extended objects: the mound of roads and railways, dams, retaining walls. The article includes a description of the possible destruction of reinforced soil base under load. It is established that the soil reinforcement by geogrids prevents adhesive failure (slip). The definition of carrying capacity of geogrid reinforced foundation is considered in terms of spatial task for the case when the ratio of base length to its width is not more than 5. The solution presented in the form of the equilibrium conditions of active and passive earth pressure. The coefficient of geogrid space work for water-saturated silt and fine sands is derivered. The optimal size and depth of geogrid inception are determined. 10.5862/MCE.30.4 geosynthetics geogrid reinforced soil https://engstroy.spbstu.ru/article/2012.30.4/ 04.pdf

RAR RUS 33-38 Far Eastern State Transport University Kudryavtsev Sergey kudr@festu.khv.ru Far Eastern State Transport University Kazharskiy A. Numerical simulation of moisture migration depending on the rate of soil freezing One of the geomechanics challenges is the quantitative assessment of deformation of soils associated with frost heaving and thawing. The main difficulty in solving this problem is the need to consider changing the state of soil freezing and thawing ground and thermophysical characteristics of the medium in a transient state. The main process in frozen soil is the redistribution of moisture in them due to water migration during freezing. When water freezes, the soil characteristics, its physical and mechanical properties change. This paper includes description of a numerical simulation method and study about humidity changing in frozen soils, depending on the rate of soil freezing. The influence of soil humidity changing on the values of strength characteristics during the process of thawing is evaluated. The developed technique of numerical simulation of the freezing and thawing process allows assessing the impact of frost heaving forces, decreasing the strength of buildings foundations and structures during freezing and thawing at the design stage. This allows the effective implementing of modern structures for soils and foundations reinforcement using geosynthetics to reduce or eliminate frost heave processes and thawing. 10.5862/MCE.30.5 numerical simulation humidity permafrost soil thawing https://engstroy.spbstu.ru/article/2012.30.5/ 05.pdf

RAR RUS 39-45 Saint-Petersburg State Transport University Shtykov V. Saint-Petersburg State Transport University Ponomarev Andrey pol1nom@yandex.ru Additional requirements for protective filtering materials of closed drainage laying in the seasonal soil frost zone The paper considers the problem of preserving the filtration properties of the drainage material in the zone of seasonal freezing. Studies have shown that drainage can lay in the zone of seasonal freezing, but the pores in the filter should not be completely filled with ice. The drainage filter may include a geotextile. The article introduces the filtration model, taking into account the freezing of water in the geotextile. The model analysis allows obtaining conclusions about changes in the porosity and the coefficient of filtration of geotextile with according to changes in ice content. The diameter of the geotextile fiber, the initial porosity and the experimentally determined water loss geotextiles are considered. The formulas relating these parameters are found. The results can be applied for the selection of geotextiles used in the zone of seasonal freezing for the drainage protection or as separating filter layers in the soil. 10.5862/MCE.30.6 geotextiles drainage seasonal freezing filtering https://engstroy.spbstu.ru/article/2012.30.6/ 06.pdf

RAR RUS 46-51 Saint-Petersburg State Transport University Kantsiber Yuriy kanziber3@yandex.ru Saint-Petersburg State Transport University Shtykov V. Evaluating drainage outflow from residential and industrial areas of North-West Russia Existing methods and techniques for calculation of hydrological characteristics of drainage systems are based on existing standards in which such parameters as climate, soils, structures and drainage system features, the data of hydrological and hydrogeological observations are not sufficiently taken into account. The article presents a method of estimating the design characteristics of the drainage from residential and industrial areas of North-West Russia, intended to substantiate structures and parameters of drainage systems, to account the volume of waste water and to determine maximum allowable discharge of water into diversion chamber. The method is based on a synthesis of available materials, with use of simple and appropriate calculated dependences of the drainage outflow characteristics on determining factors. Various factors of the soils hydrological regime are taken into account (climate, type of water supply, drainage structures and parameters of the network). The infiltration inflow and drainage flow for the north-western area of Russia are calculated. 10.5862/MCE.30.7 residential and industrial areas drainage outflow hydrological characteristics water balance analytical method https://engstroy.spbstu.ru/article/2012.30.7/ 07.pdf

RAR RUS 53-56 Peter the Great St. Petersburg Polytechnic University Girgidov Artur ardgir@mail.ru

29 Politechnicheskaya St., St. Petersburg, 195251, Russia

The time of groundwater free surface lowering before foundation pit construction On the basis of plane free surface gravitations groundwater flow model and some assumptions similar to ones employing in infiltration and quasistationary problems the time of the necessary lowering of free surface before the building of pit is considered. For the lowering the group of wells along the pit perimeter is used. The wells are located so close to each other that formation a filtration flow by them is equivalent to dewatering by using a narrow vertical slit along the perimeter of the excavation. The time is calculated on the basis of condition that at the beginning of construction the level of ground water within the excavation must be below the design elevation of excavation bottom, and outside it smoothly changing water flow to the slit must be formed. The formulas for the time of lowering from initial natural level before building of pit to finite level equal to the bottom of pit are obtained. The example of calculation is discussed. 10.5862/MCE.30.8 groundwater pit free surface flow lowering of free surface group of wells time of lowering https://engstroy.spbstu.ru/article/2012.30.8/ 08.pdf