The Creation of Geotechnical Seismic Isolation from Materials with Damping Properties for the Protection of Architectural Monuments

Abstract

This paper presents the results of a study on the relevance of seismic isolation systems for protecting architectural monuments from seismic and vibration impacts. This work aims to develop a method for protecting architectural monuments from seismic and vibration effects by installing geotechnical seismic isolation systems made of various geomaterials, such as a silicate soil mixture (SSM), a cement–soil mixture (CSM), a bitumen–soil mixture (BSM), and a rubber–soil mixture (RSM). The novelty of the work lies in the results of studying the wave processes in different models of geomaterials to assess their effectiveness in a seismic isolation system in the form of damping barrier screens to ensure the seismic resistance of architectural monuments. By comparing the amplitude–frequency characteristics of various geomaterials, it was found that the rubber–soil mixture (RSM), the cement–soil mixture (CSM), and the bitumen–soil mixture (BSM) have the most effective damping properties. A proposed method for protecting architectural monuments with geotechnical seismic isolation in the form of vertical screen barriers and technology for their installation ensures the integrity and safety of architectural monuments at all stages of construction and operation.

1. Introduction

The EM-DAT database recorded 7348 natural disasters between 2000 and 2019, causing approximately 1.23 million deaths, with earthquakes and tsunamis accounting for 58% of the casualties. The Sendai Framework for Disaster Risk Reduction 2015–2030 established priorities and targets for disaster risk reduction worldwide. An expert group from academia and industry has put forward a strategy to reduce risk by developing seismic isolation systems and damping devices to improve the resilience of buildings and structures [1].

A significant number of the architectural monuments belonging to the ancient heritage of Kazakhstan and Central Asia, included in the world cultural treasury, are located in zones of high seismic activity, with different characteristics of the propagation of seismic waves under complex engineering and geological conditions. Over the past hundred years, significant earthquakes and man-made disasters have occurred in these territories, revealing the vulnerability of architectural monuments. For example, the Mausoleum of Khoja Ahmed Yasawi, representing the architectural and cultural heritage of the 14th century, is located in a zone with seismic activity reaching 7 points in the presence of complex soil and hydrological conditions. The problem of ensuring seismic stability and the protection of historic structures in the territory of Kazakhstan is becoming increasingly urgent since it is necessary to preserve and transfer them in their pristine historical condition from generation to generation.

Seismic isolation is widely used as an effective strategy in the design of earthquake-resistant structures [2,3]. Traditional foundation isolation systems such as elastomeric, lead rubber [4], single concave bearings [5], sliding elements, friction pendulum systems [6], and sliding isolation devices [7] are quite expensive and economically and technically difficult to install for the seismic isolation of buildings and architectural monuments [8,9,10,11,12].

An innovative method for protecting structures—the geotechnical seismic isolation of buildings to dampen seismic waves—has recently attracted a lot of attention [2]. It consists of absorbing the seismic energy transferred from the soil to the superstructure by placing a surface layer to reduce the accelerations that penetrate the structure from the soil [13]. This method, based on the concept of reducing seismic loads rather than increasing the seismic resistance of structures, is a surprisingly simple approach to earthquake protection [14]. If we compare geotechnical seismic isolation devices with traditional methods for the seismic strengthening of buildings, then GSI is much cheaper than its analogs [15]. Seismic dampers allow buildings to dampen vibrations and absorb earthquake energy, minimizing damage [16,17,18].

Among the types of geotechnical seismic isolation proposed to improve foundation soils, gravel–rubber mixtures (GRMs) with rubber grains made from waste tires have aroused significant research interest due to the excellent mechanical properties of their materials [19,20], with modeling of their dynamic characteristics during earthquakes [21] in terms of the dynamic interaction between the soil structure and the foundation [22]. Also, using soil–rubber mixtures under foundations is an environmentally sustainable and inexpensive solution; using rubber grains from end-of-life tires in mixtures can create a modern recycling system that will reduce the supply of scrap tires worldwide [23]. Another option is that rubber–sand mixtures, due to their low shear modulus and high initial damping properties, can be used as an alternative to soil to reduce ground motion when seismic loads are a major concern. Recently, flexible foundations composed of a sand–rubber mixture (SRM) have been proposed to protect the soil from ground vibration, a new trend in the low-cost earthquake mitigation research [24].

However, the main disadvantage of rubber-granulated soil mixtures is that the addition of rubber significantly decreases the hardness of the granular soil. An alternative is sand–bitumen mixtures, which can be used as damping materials in geotechnical seismic isolation systems [25]. There are also simpler methods for seismic isolation using stone pebbles [26].

In the context of seismic screen geostructures, materials of various densities have been proposed that have damping properties and device manufacturability. Among them are soil, reinforced concrete, metal, and piles, which are used to shield objects from the effects of earthquakes. Numerical simulation results demonstrate these isolation systems’ effectiveness in reducing horizontal and vertical movements in the subgrade. However, due to specific parameters, such as density and deformation modulus, these type of geostructures have limitations in their application [27,28].

Many researchers have identified the general principles and fundamentals for developing and evaluating the effectiveness of seismic protection, including innovative protection systems against various types of seismic waves. The introduction of screening in the form of walls or trenches to reduce the dynamic impacts on buildings and structures is widely used in many countries. The lack of reliable data on the wave and dynamic characteristics of soils is the main obstacle to creating a reliable, practical analytical base for seismic shielding.

In recent decades, a number of experimental and computational studies have been carried out to study seismic isolation systems using wave barriers. Such barriers can be in the form of unfilled trenches filled with various materials, such as bentonite mortar, sawdust, sand, walls of concrete, sheet piling, or piles installed in the ground [29].

Studies involving different types of seismic barriers are of interest, including vertical, horizontal, V-shaped, and soft barriers. The results of numerical experiments and laboratory and model studies have confirmed the effectiveness of seismic barriers as seismic isolation systems. A mathematical model was developed by studying the frequency characteristics of seismic waves and the speed of their propagation. The parameters of the vertical barriers were obtained to reduce the amplitude of displacement and the acceleration on the surface behind the barrier. Many researchers note that quantitative assessment of the effectiveness of seismic barriers depends on their parameters, such as their width and depth, their location relative to the isolation object, and, above all, the trench filler material [30].

One striking example is the installation of geotechnical seismic isolation based on introducing polyurethane into the soil. This solution significantly reduces surface waves. This method is an alternative to structural interventions and is especially useful for existing buildings in terms of preserving their appearance [31]. It is more often used to protect historical buildings and architectural monuments.

Each seismic isolation method is characterized by unique operating principles, the use of vibration damping means, and the characteristics of the interaction with earthquakes. In the context of preserving architectural monuments, horizontal and vertical seismic barriers, which are damping barrier screens that protect buildings from the surface waves of earthquakes or underground explosions, are considered important alternative methods [32,33].

Analysis of the available approaches to ensuring seismic resistance has revealed insufficient scientific and technical justification for the effectiveness of seismic isolation and seismic damping systems in design solutions and technologies for their implementation. To solve this problem and ensure the seismic resistance of architectural monuments, alternative methods and means of seismic protection and seismic isolation at both the national and international levels have been developed. Our proposed geotechnical seismic isolation system is a measure of protection against seismic and vibration impacts. It can also serve as a seepage barrier, protecting architectural monuments from the effects of groundwater.

As part of this study, scientific works were analyzed to assess the structural and seismic characteristics of architectural monuments subjected to earthquakes. In particular, the paper [34] provides valuable data on the impact of seismic events on one of the oldest monuments in Spain. In tandem with this, reference [35] considers an integrated approach to analyzing the stability of structures based on modern technologies and techniques. Additionally, paper [36] demonstrates the application of methods based on background vibration analysis to assess the seismic reliability of the bell tower of the Cathedral of St. Lawrence in Genoa, Italy, highlighting the importance of integrating non-invasive technologies into the assessment process for historic structures. These studies confirm the need to introduce innovative seismic isolation methods to protect cultural heritage in seismically active regions.

In this study, a method for studying seismic waves in a laboratory was developed to determine the amplitude–frequency characteristics and damping efficiency of some geotechnical seismic isolation geomaterial models to study the dynamic properties of soils. This study is aimed at comparing different models of geomaterials for geotechnical seismic isolation to compare and determine the attenuation values of the waves passing through the proposed compositions. An experimental comparison is carried out of the seismic isolation characteristics of soil, silicate soil, cement–soil, and bitumen–soil, with the determination of the physical and mechanical characteristics of the tested soils and calculation of the damping coefficients. Developing innovative seismic isolation methods based on new operating principles and with improved modified properties is an essential task to reduce the inertial seismic loads on a structure. However, issues still need to be addressed related to assessing the effectiveness of various seismic isolation systems, which depends on many factors, such as their shape and parameters, the properties of the screen materials, and others. These aspects require further research to be fully understood. To achieve the goal of preserving architectural monuments using the proposed soil models, it is recommended that vertical barrier screens be arranged in the form of cylindrical and cone-shaped damping barrier screens, which can be considered in detail in future studies. These structures are distinguished by their high reliability and manufacturability in ensuring the seismic resistance of architectural monuments.

2. Materials and Methods

2.1. Materials

For testing, natural soil was used, taken from a well 10 m deep in the foothills of the city of Almaty (Latitude: 43°15′24″ N. Longitude: 76°55′42″ E), located in a seismic zone with an intensity of 9–10 points. The selected soil has characteristics similar to the soil that is located around the architectural monuments of Turkestan, including the mausoleum of Khoja Ahmed Yassawi, which is listed as a UNESCO World Heritage Site. The soil for testing had the following physical characteristics: its humidity was 12.15%; the soil moisture at the yield boundary using the balancing cone method was 30.2%, the lower limit of plasticity; the soil moisture at the rolling boundary was 18.7%; and the maximum density was also determined to be 2.01 g/cm³ at 18.53% humidity. All the tests were carried out in accordance with the standards GOST 5180-2015 (GOST, government standard) [37] and GOST 22733-2016 [38]. The main physical characteristics are shown in

Table 1. Physical characteristics of the soil (loam).

Soil Density ρ, g/cm3	Soil Moisture W, %	Soil Skeleton Density ρd, g/cm3	Porosity Coefficient e	Plasticity Index IP	Density of Soil Skeleton (Particles) ρs (g/cm3)
1.39	12.15	1.3	1.08	11.5	2.71

.

The mechanical properties of the soil without impurities (SWI) were also determined using a single-plane cutting device, the ASIS GT 2.2.3. Soil testing using the single-plane cut method was carried out to determine its strength characteristics, namely the angle of internal friction, which turned out to be φ = 20.7152, and its specific adhesion, which turned out to be c = 0.0217. The tests were carried out according to GOST 12248-2010 [39]. Figure 1 shows the test results.

To prepare the mixture of soil and silicate (SSM), sodium liquid glass was used according to GOST 13078-81 [40]. The sodium liquid glass had the following parameters: mass fraction of silicon di-oxide: 35%; mass fraction of iron oxide and aluminum oxide: 0.9%, mass fraction of calcium oxide: 0.2%; silicate modulus: 3.3; and density: 1.47 g/cm³. The advantages of soil–silicate are its chemical stability, hardening, and environmental friendliness. Its disadvantages, cost, and efficiency depend on the type and structure of the soil and may be less pronounced in some conditions.

To prepare the mixture of soil and bitumen (BSM), rubber–bitumen mastic was used with the following parameters: density: 1130 kg/m³; viscosity: 145 MPa/s; solids content: 70%; and abrasion resistance: 6 kg/mm. The advantages of soil–bitumen are its water resistance, elasticity, and durability. The disadvantages of soil–bitumen are its cost and temperature sensitivity.

To prepare the mixture of soil and cement (CSM), Portland cement, grade M-400, manufactured according to the GOST standard 31108-2003 [41], was used. The parameters were an ultimate compressive strength (after 28 days) of 0 MPa and a density in its loosened state of 1200 kg/m³. The advantages of soil–cement are improved strength and stability, low cost, an improved damping capacity, and high damping coefficient values, which make it effective in minimizing vibrations. The disadvantages of soil–cement are its rigidity and water permeability.

To prepare the mixture of soil and crumb rubber (RSM), crumb rubber manufactured in accordance with STO 2511-001-58146599-2004 was used [42]. The crumb rubber had the following parameters: fraction: 2–4 mm; textile content: 0.01%; moisture content: 1.5%; presence of metals: 0.1%; bulk density: 650 kg/m³; strength: 8 MPa; hardness: 75 ShorA units; elongation: 210%. The advantages of soil–rubber are its high elasticity and excellent vibration absorption, as well as the fact that the use of waste rubber promotes recycling and waste reduction. The disadvantages of soil–rubber are the aging of the material and it requiring special mixing and laying methods; the properties of recycled rubber can vary greatly, which affects the quality of the final product.

2.2. Methods

2.2.1. The Theory of Recording Earthquakes with Accelerometers

Using accelerometers, a mass is attached to the device body with rigid connections, which makes the period of natural oscillations in this system very small, significantly smaller than the periods of the oscillations to be measured. However, in an earthquake, the mass moves along with the body, with the deformation recorded in proportion to the inertial forces. By measuring these deformations, it is possible to simulate ground accelerations during an earthquake. The nature of different earthquakes is different and depends on many factors, including the unsteadiness of the oscillatory process of the Earth’s surface, its variable amplitude, and period.

The recorded oscillation process contains three main phases: (a) the initial phase: the initial segment of the recording, in which relatively small amplitudes with a high oscillation frequency are detected; (b) the main phase is the most intense section in terms of the vibration amplitudes, the transition to which is clearly expressed in the recording. The arrival of transverse, surface, and other types of waves causes the appearance of the main phase. The periods of the oscillations in this section are almost the same as in the initial phase; (c) the final phase: a recording section characterized by a gradual, although irregular, decrease in the amplitude of the oscillations. This phase differs from the previous ones in terms of the more extended periods of the oscillations. The transition from the main phase to the final phase needs to be clearly expressed. The horizontal components of acceleration are commensurate with each other and usually do not depend on the angle of the position of the recording device relative to the epicenter. The duration of the soil vibration process is 10–40 s.

According to the work of many researchers, the magnitude of soil displacements under seismic impacts, depending on the intensity of the earthquake and the soil conditions, can reach 100 mm. In particular, the displacements are approximately 15 times less for rocky soils than those for loose soils at the same earthquake intensity. The most characteristic periods of seismic impact are in the 0.1–1.5 s range. Most buildings designed in seismic areas are located within these same limits, so these characteristics are important.

It has also been noted that the highest ground accelerations during earthquakes are usually in the short-period spectrum range from up to 0.5 s. In this case, the soil accelerations can be up to 0.4 times greater than the acceleration of gravity, and sometimes more. For a magnitude 7–9 earthquake, the most typical values of the maximum accelerations are correspondingly observed within the range of 0.05 + 0.4 g.

When analyzing the recording of the oscillatory process, in addition to the above factors, the ground conditions of the recorded point must be taken into account. Experimental observations have shown that different soils correspond to the prevailing periods of oscillations characteristic of the given soil conditions.

2.2.2. Experimental Program

In this experiment, the UG-F proctor device was used to compact the soil, in which all the soil models were loaded into their assembled forms. From the samples, a layer of soil 50–60 mm thick was used, and its surface was slightly compacted by hand. Compaction was carried out with 40 blows of a load on an anvil from a height of 300 mm, fixed onto a guide rod. A similar operation was carried out with the three layers of soil and the soil models sequentially loaded into the mold. Before loading the second and third layers, the surface of the previous compacted layer was loosened with a knife to a depth of 1–2 mm. Before laying the third layer, a nozzle was installed in the mold. After compacting the third layer, the nozzle was removed and the protruding part of the soil flush with the end of the mold cut off. The thickness of the protruding layer of cut soil was no more than 10 mm. Afterward, a base was prepared from a container with a larger diameter than that of the UG-F device, into which soil was loaded, and a BC 111 accelerometer was installed in Figure 2. It had the general-purpose parameters for built-in ICP standard (IEPE) electronics: sensitivity: 10 mV/g; frequency range: 0.5 … 15,000 Hz.

Dynamic effects on the soil were created by throwing a load weighing 469 g from a height of 25 cm onto the surface of the soil models. Due to the impact, pulse vibration occurred. The BC111 accelerometer recorded vibrations lasting 1 s and sent them to a ZET 017-U8 spectrum analyzer with the following parameters: dynamic range: 80 dB; frequency range: up to 20 kHz. The ZET 017-U8 spectrum analyzer was connected to a laptop, and the Zetlab software package was pre-installed to collect and analyze the data from the accelerometer. The maximum acceleration value assessed the magnitude of the impulse vibration. For each model type, six tests were carried out to find a more accurate average value for the wave amplitude.

First, the soil without impurities (SWI) was tested. Using the Zetlab software package, we received information in the form of a diagram and the values of the main indicators, such as the minimum amplitude value, maximum amplitude value, mathematical expectation, root mean square value, standard deviation, and fundamental frequency, shown in

Table 2. Acceleration statistics for soil models.

Parameters	Soil without Impurities	Soil–Cement	Soil–Bitumen	Silicate Soil	Soil–Rubber
Minimum amplitude value	−11.152	−6.6625	−3.78249	−4.22825	−7.42375
Maximum amplitude value	6.85825	2.15185	1.40175	2.804	2.477875
Mathematical expectation	−0.42675	0.009475	0.233575	−0.10678	0.1355
Mean square value	1.864	0.366	0.469875	0.29925	0.651
Average square deviation	1.807	0.36075	0.3975	0.27925	0.63575
Main frequency	0.00085	0.00225	0.000825	0.0875	0.02975

.

The second test was of the cement–soil mixture (CSM). The optimal amount of cement added as a percentage was 18% of the total volume of the mixture. The soil–cement ratio was chosen according to SP 291.1325800.2017. The results for the soil–cement reinforced structures are shown in Figure 3 as a graph of the cement consumption required to ensure the strength of soil–cement for various types of soil. The soil–cement was tested in a plastic bag for better sliding of the composition inside the device in case the composition hardened. According to the results of other studies for soil models, the strengths were 0.8 MPa for the RSM [25], 1 MPa for the BSM [26], and 3 MPa for the SSM, in accordance with GOSTR 59706-2022 [43].

In subsequent experiments, the following were tested, the SSM, the BSM, and the RSM, with percentages equal to the amount of additive in the CSM used, which was 18%. For all the experiments, the recording was for six experiments each.

Figure 4 shows a schematic representation of the process of preparing a mixture from the soil models for geotechnical seismic isolation, which included the following components: the CSM, RSM, SSM, BSM, and SWI. This process plays a vital role in soil seismic isolation, aimed at improving the damping properties of the soil. The figure shows the various stages of the preparation and mixing of each component, considering their proportions: soil: 82%; additive: 18%.

Figure 5 shows a general view of the experimental setup designed for studying and analyzing the damping properties of the presented soil models and their behavior under conditions of vibration excitation. This setup allowed for a series of tests and observations to evaluate the damping properties of the soil models. Acceleration data obtained from the BC111 accelerometer are recorded using a ZET 017-U8 spectrum analyzer and transferred to a computer with data analysis software. Accelerograms are recorded on the computer screen. The total recording duration is 1 s, and the recording duration after impact is 0.5 s. Figure 5 shows the experimental setup for all the soil models. In the foreground is a device for soil compaction, the UG-F proctor device, on which various soil models are located. The standard compaction device is installed on a prepared base, and the BC111 accelerometer is installed to conduct the experiments. The accelerometer is placed on the base to measure the characteristics of the seismic waves as they pass through the ground.

This section presents a method for determining the amplitudes of the waves passing through the presented soil models. This study aims to determine how effective the geomaterials of the seismic isolation system made from the BSM, the SSM, the CSM, and the RSM are compared to ordinary soil without impurities, the SWI. This methodology for implementing geotechnical seismic isolation aims to ensure the safety and durability of architectural monuments both during construction and during operation.

3. Results

Figure 6 shows the measured acceleration amplitudes of all the soil models. The ground acceleration of the SWI is chaotic due to it having the largest amplitude value; the waves are not damped during the entire recording period of 0.5 s. The second largest amplitude indicator is that of the RSM. The amplitude in the CSM after the impact immediately decreases by 3–4 times, which shows that a damping element was added to the soil, and wave damping occurs immediately after the initial impact. The test readings for the SSM and the BSM have approximately the same values and wave attenuation patterns.

The graph shown in Figure 7 represents the dependence of the vibration amplitude on the type of soil model. The soil models are plotted on the abscissa axis (horizontal axis), and the vibration amplitudes are plotted on the ordinate axis (vertical axis). The graph also shows a trend line from larger to smaller for different types of soil model. Each bar represents the average of the maximum vibration amplitude from the recorded test results.

Analysis of the graph determined how different types of soil affected the wave transmission. This established that different soil models dampen waves differently. The highest value was shown by the soil without impurities (SWI), which was expected. The next highest value was that of the RSM, which dampened the wave of the SWI by 33.43%; the next highest indicator was that of CSM, with an indicator of 40.26%; then there was the SSM, with an indicator of 62.08; and the most effective was the BSM, which showed a decrease in the wave amplitude of 65.98%.

The amplitude spread of the presented models varies in magnitude. The maximum amplitude value was chosen as the average value from the results of six tests. For the soil models, it was as follows: SWI—11.152, RSM—7.423, CSM—6.662, SSM—4.228, and BSM—3.782.

Based on the data obtained, we can conclude that all the types of geotechnical seismic isolation materials included in the experiment can be used to protect buildings, especially architectural monuments. Based on the data obtained, in the future, we will develop effective methods for seismic isolation in the form of the vertical screen barriers presented in Figure 8 to protect architectural monuments from seismic influences.

4. Discussion

Based on the results of experimental studies, the damping coefficient is determined.

The damping factor is a parameter used to describe the damping, or the reduction in the amplitude of the vibrations, in a system. It measures how quickly the amplitude of an oscillation decreases over time.

Many studies conducted on the amplitude–frequency characteristics of soils evaluate the attenuation of vibrations according to the damping coefficient; research by scientists shows that the addition of geomaterials to soil, significantly reduces its dynamic shear modulus and increases its damping coefficient [25,26].

The damping coefficient is calculated based on the data on the amplitude of the oscillations and the time after which the amplitude decreases by a factor of e (usually, this time is called the “damping period”); the following, Formula (1), is used to calculate the damping coefficient ζ:

$$\zeta =\frac{1}{n},$$

(1)

where n is the number of periods during which the amplitude decreases by e times.

A_o and A_n are the initial and final vibration amplitudes, respectively. The relation can be obtained in the following, Formula (2):

$$\frac{A_n}{A_o}=e^{-\zeta n},$$

(2)

If the initial amplitude A_o and the final amplitude A_n are known, then n can be found as (3):

$$\mathrm{n}=\frac{\ln \left(\frac{A_n}{A_0}\right)}{-\zeta },$$

(3)

Thus, if the initial amplitude A_o and the final amplitude A_n are determined, and the number of periods n during which damping occurs is determined, we use this formula to calculate the damping coefficient ζ, expressed as the ratio of the initial (maximum) to the final (minimum) amplitudes of the oscillations according to the following, Formula (4):

$$\zeta =-\frac{ln\frac{A_{min}}{A_{max}}}{\sqrt{{\pi }^2+{ln}^2\left(\frac{A_{min}}{A_{max}}\right)}}$$

(4)

In this experiment, the minimum value A_max and the maximum amplitude value A_min are taken into account.

Table 3. Damping coefficients of soil models.

Soil Model Name	Damping Coefficient
	Experiment 1	Experiment 2	Experiment 3	Experiment 4
Soil without impurities (SWI)	0.2526	0.0755	0.1763	0.1219
Cement–soil mixture (CSN)	0.3306	0.3655	0.4864	0.2197
Bitumen–soil mixture (BSM)	0.4687	0.3079	0.2532	0.228
Silicate soil mixture (SSM)	0.1249	0.1194	0.1353	0.1366
Rubber–soil mixture (RSM)	0.2538	0.427	0.313	0.334

presents the results of measuring the damping coefficient for various soil models. Based on the damping coefficient values, the ability of a material to absorb vibration energy is assessed for five different types of soil: the SWI, CSM, BSM, SSM, and RSM. The results of these measurements fluctuate depending on the soil model, reflecting their different damping efficiencies.

Figure 9 is a graph showing the values of the soil damping coefficients, which represent the dependence of these coefficients on the presented soil models. As is known, the soil environment, depending on its physical and mechanical properties, can absorb surface waves, especially its density, porosity, moisture, and soil structure formation parameters. The introduction of composite materials into the soil structure significantly changes these parameters. As elastic material, the presence of rubber crumbs in the soil increased the damping coefficient to 0.33195. Also, the introduction of bitumen into the soil structure made it possible to obtain an elastic–plastic geomaterial with a high damping index of 0.31445. The lowest damping indicator was shown by the SSM. Its damping coefficient was 0.129; this is caused by the high viscosity of the liquid, which slows down the dissipation of vibration energy. The viscosity of the liquid creates resistance to the movement of soil particles, which prevents the rapid transfer of vibration energy. Then, the SWI showed an indicator of 0.156. The indicators of the remaining soil models show high damping coefficients; among them, the highest indicator was that of the CSM, with a damping coefficient of 0.3505.

Studies conducted on similar geomaterials, such as soil–bitumen, also show high damping coefficients in experimental installations [26]. A comparison of similar experiments on soil–rubber, with different contents of rubber in the composition of the soil mixture, showed with increasing rubber an increase in the damping efficiency of up to 30% under the conditions of a field experiment [25].

Analysis of such graphs allows us to understand which factors have the greatest influence on the soil damping and seismic isolation coefficients and how these coefficients change under different conditions. This helps us to develop more effective geomaterials for seismic isolation and the protection of architectural monuments in the form of vertical screen barriers.

Many seismic isolation systems for architectural monuments have been developed, and different approaches to design and technologies for their installation have been proposed. The method we propose is distinguished by its effectiveness in reducing the seismic impacts on architectural monuments and the reliability of the technology for their construction at all stages of construction and operation. The technology for constructing geotechnical seismic isolation in the form of vertical screen barriers made of geomaterials is similar to the installation of bored piles. A well is drilled with a rolling machine device to compact the soil of the well wall when drilling, as shown in Figure 10 in three stages: (1) rolling out the well to the design depth, (2) filling the well with a prepared mixture of the geomaterial of the first layer, (2.1) filling the well with a prepared mixture of the geomaterial of the second layer, (3) compaction of the laid geomaterial of the first layer, (3.1) compaction of the laid geomaterial of the second layer. The parametric characteristics of the vertical barriers, the type of geomaterial, the thickness of the screen in 2–3 rows, the location of the building, and its depth depend on the engineering and geological conditions at the site of the architectural monument. The technology of packing a screen barrier well is carried out in stages until the optimal density of the geomaterial is created, using the technology of installing bored piles. In installing geotechnical seismic isolation, the organizational and technological reliability of its installation and the safety of the architectural monuments are ensured.

Implementing geotechnical seismic isolation systems to protect architectural monuments and infrastructure represents a cutting-edge approach in the construction industry. However, despite their significant benefits, certain limitations and problems can affect the practicality, durability, and cost-effectiveness of these systems. For example, thorough study of the geomaterials, design, and calculations of seismic protection systems is required, making their implementation complex and time-consuming. Equally, the engineering and geological conditions of the site and the specifics of architectural monuments can significantly complicate the development and implementation of projects. Many geomaterials, including asphalt and rubber, are subject to aging and environmental degradation, which can reduce their effectiveness over time. Over time, seismic isolation systems can be subject to erosion or subsidence, especially if they are located in active hydrogeological zones, requiring additional investment to strengthen and maintain them.

Despite the potential problems and limitations, properly designed and installed geotechnical seismic isolation systems can significantly improve the seismic resistance of landmarks and other important structures. This requires not only technical innovation but also a strategic approach to the material selection and the design and integration of systems into existing infrastructure. The organizational and technological aspects must be carefully designed to minimize the risks and maximize the long-term value of seismic safety investments.

Our approaches to the design and technology of constructing seismic protection and seismic isolation systems can be used as the basis for research, analysis, and design in organizations involved in the preservation of architectural monuments. Standards establishing the organizational and technical reliability of the installation of geotechnical seismic isolation systems contribute to forming a regulatory framework and developing recommendations to ensure the integrity and safety of architectural monuments at all stages of construction and operation.

5. Conclusions

To effectively protect architectural monuments, geotechnical seismic isolation vertical screen barriers can be used, which perform the functions of intercepting, dispersing, and refracting surface waves.

Experimental studies of the parametric characteristics of materials used as filler for the barrier screen, including the physical, mechanical, and acoustic properties of a CSM, an SSM, a BSM, and an RSM, showed the excellent damping qualities of these geomaterials.

All the types of geomaterial models of a geotechnical seismic isolation system demonstrated a reduction in waves compared to the pure soil. The BSM was identified as the most effective among the soil models, which reduced the wave amplitude by 65.98%.

The results of amplitude–frequency studies show excellent damping coefficient values: SWI—0.156575, RSM—0.33195, CSM—0.35055, SSM—0.12905, BSM—0.31445. According to the results obtained, it is clear that vibrations decay most quickly for the RSM, the CSM, and the BSM, and lower values were found for the soil without impurities (SWI) and the SSM.

Thus, reducing the amplitude of seismic vibrations and providing a higher damping coefficient for geotechnical seismic isolation lead to increased safety and durability and save lives, which makes this technology essential and helpful in protecting buildings and infrastructure from seismic hazards, in this case for the protection of architectural monuments.

This technology of seismic isolation using vertical bored barriers will ensure the organizational and technical reliability of the installation of geotechnical seismic isolation systems and contribute to the integrity and safety of architectural monuments at all construction and operation stages.

Geotechnical seismic isolation is a promising direction in earthquake-resistant construction. However, its implementation requires an integrated approach that considers both the technical and economic aspects and the specifics of its application in various geological conditions. Effective use of this technology is possible with careful planning and consideration of all the factors affecting the system’s functionality and durability.

6. Patents

• Besimbaev, E.T.; Zhautikov, E.Z.; Shokbarov, Y.M.; Irgibaev, T.I.; Besimbaeva, L.E.; Nietbay, S.E. Screen for protecting buildings and structures from seismic shocks during earthquakes and influence of man-made sources of vibrations, 36536, E02D 31/08, KZ, 5 January 2024, bulletin No. 1, 5 https://gosreestr.kazpatent.kz/Invention/DownLoadFilePdf?patentId=367433&lang=ru (accessed on 5 January 2024).
• Besimbaev, E.T.; Zhambakina, Z.M.; Irgibaev, T.I.; Besimbaeva, L.E.; Nietbay, S.E.; Screen for protecting buildings and structures from seismic shocks during earthquakes and influence of man-made sources of vibrations 36537, E02D 31/08, KZ, 5 January 2024, bulletin No. 1, 5 https://gosreestr.kazpatent.kz/Invention/DownLoadFilePdf?patentId=367434&lang=ru (accessed on 5 January 2024).