On the basis of the measured values of lateral displacements of some engineering,the limitation of lateral displacement measured by inclinometers and side pilings is analyzed.

Based on the introduction to arrangement and observation of side piling, forward intersection method, which is commonly used in lateral displacement measuring with side piling, is presented in the article, and then the limitation in the measurement is brought out.

Using the straight line which crosses the center point and the crossing point, this paper, puts forward the way choos a certain point on the symmetric axis as an instrument station and then staking out the curve center line point and boundary line point.

According to road designing data of mileage,coordinate,azimuth angle of tangent or straight line,curve radius,the length of spiral line from main point of curve or straight line starting point,we can calculate the coordinates of center line points and boundary line points in any form of road under the same coordinate system.

The paper introduces the principle of laying out railway horizontal curve by using polar coordinate method at arbitrary point, and concludes the mathematic models of middle stake and side slope stakes coordinate calculations.

The calculating methods of middle stake coordinates also can be used in the highway.