# Effect of Soil Box Boundary Conditions on Dynamic Behavior of Model Soil in 1 g Shaking Table Test
###### Abstract  
In order to evaluate the effects of soil box boundary conditions on the dynamic soil behavior, the Rigid Box (RB) and the Laminar Shear box (LSB) were constructed and 1 g shaking table tests were carried out for various boundary conditions. The boundary effects of the RB and the LSB were compared. To reduce the boundary effects of the RB, sponges, 5 cm, 10 cm, and 15 cm in thickness, were attached to the two end sides of the RB. A model soil was constructed on flat ground, and the acceleration and amplification occurring in the center of the soil were analyzed by spectrum and peak ground acceleration. Compared with the RB, the center and wall accelerations of LSB were very close to each other. This implies that the LSB can better simulate the behavior of the infinite half space than the RB. 1-g shaking table test; boundary effect; Rigid Box; Laminar Shear Box; acceleration amplification 2020 10 4642 10.3390/app10134642 10.3390/app10134642 10.  
soil box include keeping a uniform section while seismic load is given, little weight, and minimum shear rigidity. In addition, no resistance to soil displacement, and no outward water leak, should be ensured. [PERSON] [3] designed a soil box in the concept of flexible shear beams, not a box, and manufactured it to act like five layers of ring type. [PERSON] [4] made a V-shaped groove between layers to insert ball bearings to minimize friction and attached a spring of low rigidity to the short sides of the soil box to get rid of rocking. In Korea, [PERSON] [5] studied how to develop a small-scale flexible shear box to produce a small laminar box, 30 cm in height, and compared the RB of the same size with ground response. [PERSON] and [PERSON] [6,7] examined the performance of the RB and the flexible shear box system through a finite element analysis of shaking characteristics, and concluded that the RB has a limited reproduction of behaviors of free field, and the LSB can make more similar reproduction of free field behaviors than the RB. [PERSON] [8] created a clay ground model and conducted a seismic simulation test to compare the boundary conditions of the flexible soil box and RB based on [PERSON] and [PERSON]'s studies. [PERSON] [9] and [PERSON] [10] used an LSB using the elasticity of a spring and simulating layer division behaviors. They used an iron board with a given spacing on the outer side from the layer-divided walls to connect the walls to the iron board to build a flexible wall. [PERSON] [1] summarized that physical modelling of scaled models is an established method for understanding failure mechanisms and verifying design hypothesis in earthquake geotechnical engineering practice. The main requirement of physical modelling is the replication of semi-infinite extent of the ground in a finite dimension model soil container. It is important to choose particular types of container depending on the problem at hand. [PERSON] [11] has summarized the soil boxes as follows: (i) RB; (ii) RB with flexible boundaries (e.g., duxseal or sponge); (iii) RB with hinged end-walls; (iv) Equivalent Shear Beam (ESB) box; (v) LSB; (vi) Active boundary box. In the most traditional box, the RB, the shear stiffness of the end walls is much higher than the stiffness of the layers of soil contained by it. This ensures the development of shear stresses in the vertical plane at the interface between the container and soil. To compensate for this, a flexible boundary such as a sponge was attached to the RB. The main advantage of the RB with flexible boundaries is the reduction in the wave reflection and the P-wave generation. The design principle of a LSB is to minimize the lateral stiffness of the container in order to ensure that the soil governs the response of the soil-box system. Therefore, we experimentally compared the RB, RB with flexible boundaries and LSB. Although there have been several studies using 1 g shaking tables with the RB and LSB, the comparative studies on the effects of RB and LSB on dynamic behavior are not available.