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To reduce the effect of dynamic traffic and seismic loads, it is proposed to use a seismic insulating support, the contact surfaces of which are pasted over with a fluoroplastic film. The dry friction coefficient for a fluoroplastic pair is 0.03-0.05. Due to the small value of the dry friction force, the support will operate both during traffic and seismic effects. Instrumental records of accelerations recorded by the devices of the ESS station No. 22, installed on a nine-story single-section large-panel building of series 158 in the city of Almaty, are analyzed. The earthquake source is 148 km from the city of Almaty. The house is equipped with a seismic isolation system. The foundations of the building are sliding supports. The values of acceleration along the height of the building are analyzed, and the spectral curves β are also constructed. The presence of 2 maxima on the spectral curves β at periods of 0.13-0.14 sec and 0.44-0.47 sec is revealed. The absence of resonance phenomena under the combined action of seismic and traffic loads is shown. The seismic support is proposed to be used on dense soils. Thus, transport and seismic loads can be effectively reduced.

Methods for calculating buildings and structures based on direct numerical integration of the equations of dynamics are very relevant. For this, a new method for generating artificial accelerograms has been proposed. The method is based on the representation of the correlation function as a sum of cosine-exponential terms. The approximation parameters are determined based on the least squares method using the Curve Fitting Toolbox SCM MATLAB package. Artificial accelerograms are generated using an autoregressive (moving average) calculation formula. The generation accuracy is illustrated by the calculation of the spectral curves. The accelerogram of the 1990 Baisorun earthquake is taken as an example. The area of application of the accelerograms obtained in this way are earthquake-resistant construction and seismic microzoning, calculation of systems with dampers of viscous and dry friction, seismic isolation systems, different non-linear systems.

During the earthquake on August 31, 2018 with a source in the Almaty region, the stations of the engineering and seismometric service registered instrumental records on rigid and flexible buildings. Accelerograms were obtained on a four-storey frame building and an 11-storey building with a steel frame. The reaction of two buildings at a given earthquake is analyzed. Spectral curves were plotted at the registration points on the roof and basement parts of buildings. The spectral curves at the basement level differ in spectral composition and spectrum irregularity. The influence of a tectonic fault on the response of an 11-storey building is revealed, and a criterion for the operation of a tectonic fault is proposed. The presence of resonance phenomena for a rigid building was established. Instrumental records are included in the accelerograms database of KazRDICA JSC. The results will be used to identify dynamic building models. This will allow you to take into account local features of seismic impact.

For the seismically active region of the southern part of the Republic of Kazakhstan, a mathematical model of seismic action has been developed based on the representation of seismic action by a non-stationary random process, which is obtained from a stationary multiplication by a deterministic envelope function. For the territory of the city of Taraz, the seismic regime of its territory and soil conditions were studied. Accelerograms of strong earthquakes were selected from the world database, the source parameters of which correspond to the parameters of past earthquakes. It was found that the calculated sample of accelerograms for the region of Taraz should include instrumental records with acceleration maxima in the range of 124–275 cm/s2, recorded on soils of the second category. For each accelerogram, the parameters of the correlation functions of the random process, the values of the effective duration and the frequency characteristics of the seismic impact are determined. This information allows to perform digital modeling of seismic impact, given as a random process. The results can be used to calculate buildings with various seismic isolation systems, high-rise and extended buildings.

For the first time, a study of the strength and deformability of the dome of the “Kazanlyk” room of the Mausoleum of Khoja Ahmed Yasawi, included in the World Heritage List by the United Nations Educational, Scientific and Cultural Organization, was carried out. The mausoleum was built in the fourteenth century. A visual inspection of the technical condition of the dome was carried out, instrumental records of micro-oscillations were obtained, and a computational and analytical assessment of the bearing capacity of the structures of a decorative dome under seismic and static influences was carried out. The technical condition of the dome is not satisfactory, there are multiple cracks along the outer surface of the dome. The technical condition of the wooden beams is not satisfactory. The presence of rotten beams, in places where they are embedded in masonry, and the presence of beams affected by fungi and insects, weaken the bearing capacity of the decorative dome. When calculating for seismic impact, the seismicity of the construction site was taken equal to 7 points. The calculation was carried out using the finite element method. Two variants of the calculation were performed - without damage and taking into account the modeling of a horizontal crack between 16 and 17 rows of stalactites with a length of ¼ of the dome perimeter. It was found that presence of a crack affects the strength and deformation characteristics of the dome. The displacement values, taking into account the simulation of the crack, changed - the maximum displacement value increased 2.7 times from 0.0256 mm to 0.0629 mm.

A resonant method of determining the dynamic characteristics of an 11-storey building with a steel frame and a 25-storey building of the Kazakhstan Hotel in Almaty is proposed. Both buildings are located near the tectonic faults. The buildings have engineering seismometric service stations equipped with digital systems. From the base of accelerograms of KazRDICA JSC, accelerograms of earthquakes were selected, under the influence of which resonant oscillations of these buildings took place. Such were remote earthquakes with epicentral distances of over 300 km. An earthquake was chosen on August 9, 2017 with a focus of 480 km from Almaty in the border region of China (Xinjiang-Uygur autonoma district). When exposed to earthquake, periods of oscillation of buildings by main and second forms of oscillation are revealed. A significant change in the periods of fluctuation during the existence of buildings has been established. In constant earthquake conditions, the selection of instrumental records was not a complex task. The results of the work can be used to determine the dynamic characteristics of buildings during its lifetime.

The behavior of the 25-storey building of the “Kazakhstan” hotel located near a tectonic fault is analyzed during the earthquake on March 26, 2018. The epicenter of the earthquake is located 68 km north-east of Almaty in Kazakhstan. A digital station of the engineering and seismometric service is installed on the hotel building. The absence of resonance phenomena of the building was revealed during the indicated earthquake. The curves of acceleration distribution in the building levels on the azimuthal plane are plotted. Significant acceleration in the vertical direction at the level of the technical floor was noted, which may be a consequence of the presence of a tectonic fault near the building. It was found that at the basement level, the period of the spectrum maximum is about 0.18 s. For the first time, the energy characteristics of instrumental records in building levels are determined. Instrumental records can be used to build seismic models.

On August 9, 2017, a strong earthquake with a magnitude Mw = 6.3 occurred in the Xinjiang Uygur Autonomous Region of China. For the first time in the last 10 years, representative instrumental data were obtained at the seismic station No. 11 (“Prospect Abay”) in the city of Almaty, equipped with a digital instrumentation and measuring system. The building is eleven-story and is made in a steel frame. In the city of Almaty, there is a significant number of residential and public buildings made in a steel frame. Using the AT 1105 sensors and the RSM-8 recorder, high-quality instrumental records of accelerations in the basement and on the roof of the building were obtained, as well as the β spectral curves. The frequency composition of the impact at the basement level has been determined. The prevailing period of fluctuation at the basement level is 0.3 sec, and at the roof level is close to 1.3 sec. It was found that during a remote earthquake, resonant vibrations of the building took place. The results of the work can be used in the design of buildings with a steel frame in the city of Almaty.

Earthquakes give rise to a significant number of problems that affect environmental, seismic, and economic risks forthelocalsand construction sites. For the first time in the last 40 years, another local zero depth earthquake was registered in the territory of the city of Almaty. In terms of intensity, this was a 3-4-point earthquake. At 100 meters from the tectonic fault, there is a 16-storey building with a stiffening core and an engineering seismometric service station. With the use of AT 1105 sensors and a PCM-8 recorder, instrumental records of accelerations in the basement and on the roof of the building were recorded, and spectral β curves were constructed. The effective duration of the seismic impact in the basement of the building was quite significant, 47-56 seconds. There is undoubtedly an increase in the intensity of local earthquakes compared to 2007-2014. It was found that at the basement level the value of the vertical component is significantly less than the horizontal one. It is assumed that the abnormally high values of acceleration in the horizontal plane are a consequence of the presence of a tectonic fault near the building. Instrumental records of acceleration (accelerograms) can be used in calculations of both the seismic resistance of an object and the assessment of environmental, social, economic, and non-economic risks.