3.1.3. Loading System's Overall Layout Scheme

In accordance with the experimental requirements, the loading devices described in the previous section were sequentially arranged along the longitudinal direction of the bridge, forming an array-based pulley-group loading system, as shown in Figure 8. In this system, even if the counterweight near the loading point affects the vertical displacement of the current loading point, due to the equal tension on both sides of the same pulley's steel wire rope, the load amplification factor of the current loading point will gradually approach seven times over time, exhibiting a self-balancing characteristic. This system overcomes the shortcomings of the hydraulic jack-loading method, in which the load values are difficult to maintain stable over a long period; the lever-loading method, where load values are easily affected by adjacent loading points; and the direct-counterweight method, where the counterweight blocks are excessively large in volume.

**Figure 8.** Overall layout plan of the model test's loading system.
