## 6 Discussion  
By carrying out the analysis and optimization of the LVT track structure under the load of a heavy-haul train, we have completed the research goal. According to the analysis of \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Position**} & \multicolumn{2}{c}{**Original**} & \multirow{2}{*}{**20 mm**} & \multirow{2}{*}{**40 mm**} & \multirow{2}{*}{**60 mm**} & \multirow{2}{*}{**80 mm**} & \multirow{2}{*}{**100 mm**} & \multirow{2}{*}{**120 mm**} \\  & & & & & & & \\ \hline T1 & 2.53 & 2.23 & 1.99 & 1.94 & 1.90 & 1.86 & 1.82 \\ Loading point 8 & T2 & 0.84 & 0.78 & 0.72 & 0.71 & 0.70 & 0.70 & 0.70 \\  & T3 & 0.54 & 0.54 & 0.54 & 0.52 & 0.50 & 0.49 & 0.48 \\  & T1 & 3.06 & 3.00 & 2.96 & 2.91 & 2.89 & 2.86 & 2.83 \\ Loading point 11 & T2 & 1.50 & 1.50 & 1.50 & 1.50 & 1.50 & 1.50 & 1.50 \\  & T3 & 2.20 & 2.21 & 2.21 & 2.19 & 2.16 & 2.14 & 2.11 \\ \hline \hline \end{tabular}
\end{table} 
Table 13: Widen TLVT in the lateral direction (MPa). \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Position**} & \multicolumn{2}{c}{**Original**} & \multirow{2}{*}{**20 mm**} & \multirow{2}{*}{**40 mm**} & \multirow{2}{*}{**60 mm**} & \multirow{2}{*}{**80 mm**} & \multirow{2}{*}{**100 mm**} & \multirow{2}{*}{**120 mm**} \\  & & & & & & & \\ \hline T1 & 3.06 & 2.91 & 2.77 & 2.62 & 2.51 & 2.43 & 2.40 \\ T2 & 1.50 & 1.48 & 1.45 & 1.39 & 1.29 & 1.21 & 1.18 \\ T3 & 2.20 & 1.86 & 1.56 & 1.32 & 1.12 & 0.97 & 0.91 \\ \hline \hline \end{tabular}
\end{table} 
Table 11: Lengthet TLVT in the longitudinal direction (MPa). \begin{table}
\begin{tabular}{c c c c c c c c} \hline \hline \multirow{2}{*}{**Position**} & \multicolumn{2}{c}{**Original**} & \multirow{2}{*}{**20 mm**} & \multirow{2}{*}{**40 mm**} & \multirow{2}{*}{**60 mm**} & \multirow{2}{*}{**80 mm**} & \multirow{2}{*}{**100 mm**} & \multirow{2}{*}{**120 mm**} \\  & & & & & & & \\ \hline T1 & 2.52 & 2.34 & 2.21 & 2.14 & 2.11 & 2.06 & 2.02 \\ Loading point 8 & T2 & 1.09 & 1.10 & 1.11 & 1.10 & 1.10 & 1.09 & 1.09 \\  & T3 & 1.15 & 1.09 & 1.05 & 1.03 & 1.02 & 1.01 & 1.01 \\  & T1 & 2.65 & 2.61 & 2.5 experiments and finite element data, it is not difficult to see that ILVT has better mechanical properties than TLVT. When ILVT is subjected to the same load, the ILVT design can reduce the vertical displacement of the rail and the supporting block, better control the sinking amount of the track, and improve the driving safety of LVT. As the load sharing rate of LVT at the loading point has been improved, it shows that the supporting block at the loading point has a stronger bearing capacity. Because part of the gauge expansion is caused by the overturning of the steel rail and the supporting block. For this type of track structure, as the axle load increases, the various indicators of the track structure response show a linear increase trend, and the maximum displacement of the rail is 2.67 mm. Comparing the test results in the literature [38], the displacement is less than the test value when the 39t axle load vehicle passes, and it can be considered that the vertical displacement of the rail meets the requirements. It can be seen from the data comparison and analysis that the design of ILVT can reduce the expansion of the gauge and the lateral spacing of the supporting block, and also improve the anti-turning ability of the rail and the supporting block under the lateral load to a certain extent, and improve the stability of the track structure. According to reference [37], the general railway track dynamic quality tolerance management value specifies the gauge tolerance value of +8 mm, and the track static geometric dimension tolerance management value specifies the gauge tolerance value of +6 mm. Under the action of 40t axle load and double axle load, the gauge expansion of TLVT and ILVT did not exceed the management value of dynamic quality tolerance of track, but both exceeded the management value of static geometric dimension tolerance.