Vol 54, No 3 (2017)

The behavior of single, reinforced-concrete, bored piles in solid rock is studied. Such a foundation can be used to transfer load from surface structures and buildings through a layer of weak soils to stronger underlying hard rock. A method is proposed for calculating piles under vertical loads taking account of the particulars of the changes in the stress-strain state of the system 'pile-rock' under compressive loads.

In offshore industry, foundations are subjected to vertical and horizontal loads due to the self-weight and wind or wave forces, and they are founded on non-homogeneous deposits where the strength increases with depth. This paper aims to evaluate the inclination factor through the study of the undrained bearing capacity of strip footings on non-homogeneous clay under inclined loading. An expression of the inclination factor is proposed.

The results of experimental studies of models of strip foundations with different angle of internal notches for determining the optimal shape of the foundation pad with broken contour of the edge zone are presented. A design solution for such foundations is proposed. New experimental data are obtained on the stress state of the sandy base of strip foundations in the entire range of loads.

Bituminous coatings can be used to reduce negative skin friction on pile. The present study investigates the other applications and the effectiveness of heated coating withelastic and visco-elastic-plastic behavior on the skin friction at soil-pile interface. Aseries of small scale physical modeling tests of short pile foundations under pullout load was carried out to study the effects of adhesive coating materials on the short pile foundation interaction. The results indicated that heated bituminous materials can significantly affect the pull-out capacity of short pile foundations.

It is shown that the physical-mechanical and thermal-moisture characteristics of high-temperature permafrost soils under process loads are interrelated. It is shown that technological process control for the purpose of increasing the carrying capacity of the base of geotechnical structures during the construction period is expedient.

An example of the development of settlement and inadmissible tilt of an oil tank during hydraulic testing is presented. Data from engineering and geological research as well as a combined numerical calculation of the base and foundation by the finite-element method did not permit predicting the considerable tilt of the tank during hydraulic testing.

The reasons for the increase in accidents and the reduction of the safety of buildings and structures built on permafrost in the last 25 years are reviewed and analyzed. Measures to ensure increased reliability and reduction of accident risks in construction in permafrost areas are proposed.

The rapid treatment of soft soil foundation is one of the main ways to solve problems associated with road construction. This study was conducted to determine the most effective stabilizer to increase the strength of wet and soft clay soils within 72 hours for rapid road construction. Extra admixtures are added to accelerate the reactions of cement and improve the stabilization effect. Using the unconfined compressive strength test (UCS), the effectiveness of admixtures was compared with that of a common cement-based binder. The results show that the addition of extra admixtures could rapidly improve the early strength of cement stabilized soils.