Masonry structures are still very common in rural areas of some countries; due to the lack of appropriate seismic design and detailed design, their seismic performance is poor. Masonry buildings with poor seismic performance often suffer damage or even collapse under the action of earthquakes. The collapse and damage to houses will bring direct economic losses and a large number of refugees, causing a huge economic burden. However, in high-seismic and cold regions, the two threats of earthquakes and frost heave can cause damage to low-rise, rigid, and heavy masonry buildings. Therefore, for high-seismic and cold regions, efforts should be made to formulate technically feasible and cost-effective measures to simultaneously reduce the seismic and frost heave risks of brick–concrete buildings.
The application of structural energy dissipation and damping technology and base isolation technology makes it possible for buildings not to collapse during earthquakes and is one of the most effective means to mitigate earthquake hazards. Structural energy dissipation and damping technology is to install energy dissipation devices in certain parts of the structure, such as metal dampers and viscous dampers [
1]. The base isolation technology places isolation materials with bearing capacity between the building foundation and the superstructure, such as laminated rubber isolation bearings and friction pendulum bearings [
2,
3]. Currently, structural energy dissipation, damping technology, and base isolation technology are widely used in improving the seismic performance of new or existing important buildings [
4,
5]. However, due to their high costs, these two methods are not feasible in masonry structure buildings in rural areas. Therefore, scholars have developed many economical and effective isolation systems [
6,
7,
8,
9,
10,
11], which are an attractive and feasible option for the isolation of rural buildings, but these isolation systems set flexible or sliding interfaces between the structure and its foundation. For high and cold regions, the frost heave risk is usually related to the freezing of moisture in the foundation soil, and these isolation technologies cannot be directly used to reduce the frost heave risk.
In recent years, geotechnical isolation technology using low-modulus materials around structure foundations has garnered significant research interest. This technology involves treating the foundation soil beneath structures, offering a potential solution to simultaneously mitigate the threats of earthquakes and frost heave in high-seismic and cold regions. The GSI technique that uses the rubber sand particles as the foundation pit backfill material (Geotechnical Seismic Isolation System based on rubber–soil mixtures, GSI-RSM) was first proposed by Tsang [
12]. Subsequently, scholars conducted extensive research in both numerical and experimental aspects [
13]. In terms of numerical research, Senetakis et al. [
14] and Pitilakis et al. [
15] investigated the response of a rubber sand layer through numerical simulation. Numerical studies by Pitilakis et al. [
16] and Panjamani et al. [
17] showed that the rubber sand layer was effective in decreasing base shear and maximum inter-layer displacement of mid- and high-rise buildings. Brunet et al. [
18] found that a rubber–soil mixture of only 2–3 m thick was sufficient to achieve a good structural seismic response. Tsang and Pitilakis [
19] analyzed the dynamic behavior of buildings equipped with a GSI system using a lumped parameter analysis model, and they also proposed the equivalent linear stiffness, viscous damping coefficient, and rocking radiation damping coefficient for ground and pre-built foundations. Forcellini [
20,
21] established a 3D numerical finite element model to evaluate the isolation potential of the GSI system. In terms of experimental research, Hazarika et al. [
22] found that the use of tire debris and/or sand-mixed tire debris as a compressible cushion could not only reduce the dynamic load of the structure but also significantly reduce the dynamic-induced permanent displacement of the structure. Xiong and Li [
23] and Bandyopadhyay et al. [
24] carried out small-scale shaking table tests on the GSI-RSM system, where rubber–sand mixtures were positioned below the concrete or rigid block as the isolation material. Anastasios et al. [
25] performed direct shear tests to sort out the failure mechanism of the rubber sand layer, further confirming its applicability in seismic isolation. Additionally, Banović et al. [
26,
27] proposed a GSI system based on a pebble layer sliding mechanism. The isolation performance of this system was validated through experiments, and the impact of foundation size on the system’s isolation efficiency was also examined. Tsiavos et al. [
28] introduced a new isolation strategy, which was defined as the “PVC sandwich” isolation strategy and evaluated the effectiveness of the proposed design method through the experimental study of the isolation structure. Kuvat and Sadoglu [
29] conducted cyclic triaxial tests on an asphalt and sand mixture that serves as damping material for the GSI system. The results showed that the asphalt and sand mixture had stronger rigidity and damping. Forcellini [
30] discussed several geotechnical isolation (GSI) techniques for bridge structures to assess seismic vulnerability. Previous scholars have conducted extensive numerical and experimental research on the GSI-RSM system, but because of the relatively high material cost of rubber sand particles, the system has not yet been applied in engineering practice, and on-site data cannot be obtained to verify its reliability. Furthermore, it remains unclear whether replacing soil with rubber sand can effectively eliminate the threat of frost heave in foundations.
Sand is a widely used, low-cost building material. Replacing soil with sand can reduce the threat of frost heave, and sand also has isolation properties that help mitigate earthquake forces. However, there is still a lack of shaking table tests on entire masonry structures with sand cushion foundations. While a shaking table test was conducted on a brick masonry building with a sand cushion [
31], the existing conclusions did not take the influence of foundation soil into account. This article proposed an economically efficient GSI-SC system, where a sand cushion is introduced between the structural foundation and natural soil to replace the original permanent frozen soil, and the sand that serves as a buffer layer is backfilled around the foundation to limit sliding displacement, as illustrated in
Figure 1. Large-scale shaking table tests of the site foundation structure system were conducted on a single-layer masonry structure model to verify the effectiveness of the GSI-SC system, and numerical simulations were conducted on the shaking table tests using ABAQUS software version 6.14 to verify the seismic response of buildings equipped and non-equipped with the GSI-SC system.