## 3 Experimental Results and Analyses
### Horizontal Deformation  
#### 3.3.1 Time-History Curves of Horizontal Deformation  
In order to further analyze the distribution of horizontal displacement of test specimen along the depth, the time-history curves of horizontal displacement of nine typical measurement points on the specimen are discussed in this section, as shown in Figure 18. Figure 18a shows the locations of nine measurement points and the distribution (red line) of the specimen considering accumulative deformation under \(\pm\)16 mm displacement load. Time-history curves of horizontal deformation of measurement points, D1, D2, D4 (the buried depth of 0 m, 0.6 m, 1.0 m), D5, D6, D7, D8, D10, D13 (the pile depth of 0.2 m, 0.4 m, 0.6 m, 0.8 m, 1.2 m, 1.8 m) are presented in Figure 18b-j respectively. In Figure 18b-j, the purple lines are the accumulative deformation curves for each measurement point. Figure 16: Equivalent viscous damping. Figure 17: Skeleton curve for the test specimen. For the measurement points of abutment, it can be seen that the time-history curve of horizontal deformation of D1 in Figure 18b is basically symmetrical and consistent with that of displacement load in Figure 8. Since the abutment revolves around the action point, the time-history curve of horizontal deformation of D1 is slightly larger than that of loading system. In Figure 18c,d, the time-history curves of horizontal displacement of D2 and D4 are smaller than that of the displacement loads, which are a little asymmetrical by the effect of steel H-pile. For the measurement points of pile, the time-history curves of horizontal deformation of D5, D6, D7, D8, D10 and D13 vary widely. In Figure 18e, the accumulative deformation of D5 is almost neglected when the displacement is less than \(\pm\)10 mm. But after that, the accumulative deformation increases rapidly, and goes up to +13.63 mm when the displacement load is \(\pm\)16 mm. The accumulative deformation makes the displacement of measurement points no longer symmetrical with time axis. In Figure 18f,g, D6 and D7 have the similar phenomenon with D5. To be noted, in Figure 18h-j, the measurement points D8, D10 and D13 have the negative accumulative deformations, which means this range of pile body moves to the negative direction as the displacement load increases. Among these measurement points, the maximum positive accumulative deformation occurs at D6, about +16.71 mm, and the maximum negative accumulative deformation occurs at D10, about \(-\)1.99 mm. Figure 19 shows the curves of accumulative deformation and displacement loads for each measurement point. It can be observed from Figure 19 that the accumulative deformation goes up with the increases of displacement load, and the growth rate is nonlinear and faster when the displacement load reaches 10 mm, especially for D5 and D6 of 1.0\(\it{b}\)\(\sim\)3.0\(\it{b}\) of pile depth. Figure 18: Time-history curves considering accumulative deformation. (**a**) The locations of nine measurement points and the distribution (red line) of the specimen considering accumulative deformation. (**b**) D1. (**c**) D2. (**d**) D4. (**e**) D5. (**f**) D6. (**g**) D7. (**h**) D8. (i) D10. (**j**) D13. The noncumulative deformation is that the whole horizontal deformation of specimen deducts its accumulative deformation, thus it is symmetrical with the time axis. In order to further understand the distribution of horizontal deformation of specimen under each step of displacement load and compare with those of previous test and traditional theory of soil-pile, the time-history curves of horizontal deformation of nine typical measurement points deducting accumulative deformation are discussed in this section, as shown in Figure 20. Figure 20a shows the locations of nine measurement points and the distribution (red line) of the specimen deducting accumulative deformation under \(\pm\)16 mm displacement load. Their time-history curves are presented in Figure 20b-j respectively. Figure 19: Accumulative deformation of each measurement point.