The measured results show that for the same distance along axial line, the maximum energy of antenna array at axial point z is proportional to the square of antenna number of the array;

The bridge axial alignment is a key point to bridge bearing capacity evaluation, disease analysis, health analysis and taking-over inspection.

In the light of characteristics that horizontal hole possesses a certain rate of curvature, the method of estimating minimum axial force at any point along a rod string is established.