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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.

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.