Scientific researches at the SPbSPU Structural Mechanics and Theory of Elasticity Department play a very important role in its activities. Department's history is tackled with outstanding scientists, who have made a significant contribution to the development of science, first of all - with world wide known academician Boris G.Galerkin.

Department officers always tried to support scientific traditions, layed by the founders of the department. In our country the department played a very imortant role in the development, introducing and popularization of Finite Elements Method (FEM), which has become the main method of modern structural mechanics nowadays. Particulary, our department was responsible for organizing and conducting of All-Union schools-seminars on FEM. High level of scientific researches, conducted at the department and its prestige among scientists of Russia and the rest of the world are associated with the authority of professor Leonid A.Rozin ,who has been the head of the department for approximately thirty years and nowadays remains one of the Russian structural mechanics scientific school leaders.

Succession of generations and preservation of structural mechanics unique scientific school traditions is the most important aim of the department. Its achievment is provided by the highest level of scientific works and qualified specialists training in this sphere.

Scientific work of the department nowadays includes researches, according to the state research programs and contractual researches, scientific resarches of students and post-graduate students, participation of officers and post-graduate students in different scientific conferences and seminars, participation of the most authoritative and experienced officers in the work of expert commissions of different kinds, opposing and critisizing of thesises and scientific transactions etc. A lot of department officers and post-graduate students received primes or grants for conducting scientific researches, participation in international conferences in regional, national and international competitions. Results of researches of the department officers and post-graduate students are published in scientific magazins and books, particulary in "Structural Mechanics and Structural Analysis." - scientific transactions, published in St.Petersburg Polytechnical University.

Serios attention of the department staff is attached to the work with young scientists. Thesises, prepeared by the department post-graduate students, usually represent serious scientific works, containing important scientific results. Their distinguishing features are deep analysis of scientific and engineering problems and wide application of the profound mathematical apparatus. Majority of works are fulfilled in accordance with scientific speciality 05.23.17 "Structural mechanics". Two officers of the department staff have permission to be post-graduate students' scientific consultants: Russian Federation Science and Technics honored worker, professor Leonid A. Rozin and the head of the department, professor Vladimir V. Lalin. Students are also take part in scientific researches.

In the variety of the department's scientific research themes the most important role is traditionally given to those, which are related with hydrotechnical and energy constructions. The department has good ties with many companies, working in these spheres, for example "Lengidroproekt" Institute, "Spetsgidromontazh" trust, B.E.Vedeneyev Hydrotechnical Research Institute, some smaller companies, working in construction business. Many of the results, received by the department officers and post-graduate students in the researches process are applied in the practical work of these and other companies. The department officers and post-graduate students participated in scientific researches, tackled with designing and analysis of concrete and soil dams, elements of high-head hydro power plants units water-flow pipes, self-elevating drilling platforms, sea-bed oil pipe-lines, water transport constructions, wind power plants, urban industry objects, transport objects and others. The majority of the researches, students' and post-graduate students' degree works include the development of the appropriate software.

For some previous years the main directions of the department researches, where its officers and post-graduate students managed to obtain important scientific results were:

• Development and studying of the problems statements regarding derivatives of unknown functions and development of their solution methods. This gives an opportunity to avoid computational errors in numerical differentiation process. Particulary, in last V.V.Lalin's researches theory of elasticity and pivot systems analysis (post-graduate student T.N.Bougayeva) problems solution methods, based on the forces method, but free of some its drawbacks and competitive in effectivity with traditionally used nowadays displacement method are developed. Similar results are received by prof.V.V.Lalin for some other problems of mathematical physics, particulary - for hydroelasticity problem.
• Constructions with unilateral joints analysis, i.e. structures or domains with seams and cracks. Prof.L.A.Rozin and assistant professor M.S.Smirnov work in this field. Particulary, in M.S.Smirnov's Candidate thisis gap iterations method modification is developed. It gives an opportunity to solve such problems taking in account friction and compliance in unilateral joints, and therefore model processes on the contact of interacting domains more exactly and in certain cases improve the problem's mathematical characteristics. Some results in the field of pivot systems with unilateral joints analysis were also obtained.
• Constructions under ice loads dynamical analysis methods development. Constructions on the sea shelf and sea-bed pipes interacting with huge ice fields and formations, such as ice or grounded hummocks, dynamical analysis methods are developed. Researches were conducted under the guiding of prof.L.A.Rozin.
• Wind power plants dynamical analysis approximate methods development and studying. Researches, conducted by prof.I.A.Konstantinov and A.A.Panfilov (Renewable sources of power and hydroenergy department), studied error values, received in the process of wind power plants dynamical analysis using simplified models. These researches have let to develop certain recommendations for using simplified models in the dynamical analysis of wind power plants constructions.
• Theory of elasticity problems in infinite domains solution methods development. Prof.L.A.Rozin with post-graduate students developed methods, based on using Finite Elements Method in combination with Green-Somiliana formula, Boundary Elements Method or other methods for solving such kinds of problems. These researches have let to take in account infinite dimensions of soil basements in the process of system "construction-foundament-basement" analysis and underground constructions analysis. Assistant professor G.S.Kolosova conducted similar researches for plates on infinite elastic basement.
• Effective algorythms and effective elements for Finite Elements Method development. In particular, new method for stresses precise definition on the contact of structure and its basement in finite-elements models with linear displacement approximation elements was developed by assistant professor B.M.Yevdokimov together with post-graduate students.