• Correspondence to "Land Improvement Projects Design Standard and Operation [Water work] design March 2014"
• Open ditch by the seismic method

Fig.1 Applied standard select in the "initial input" screen

About "Land Improvement canal work 2014", the following switches has been added. (initial values are displayed in red)

About inner water pressure, static water pressure by filled water and by pressure water can be loaded concurrently. The concurrent loading is available when inside water is full.

Fig. 2 Static water pressure by filled water (left) and by pressure water (right)

In reference to live load positions of double box, stylized (vertical) live loads of double or triple box culvert is available. Selected live loads will be added automatically.

In addition, a design horizontal seismic intensity used for calculating inertia of seismic load is automatically rounded to two decimal places. An acceptable value according to a standard is also computed automatically.

Fig.3 3D bar arrangement figure and bending moment figure of open ditch		M figure (normal) and M figure (seismic)

As for soil pressure loading of seismic case, static soil pressure and ground displacement frequency loading are given for the seismic deformation method, but only soil pressure based on Coulomb's earth pressure formula is loaded for the seismic coefficient method. Inertial force is also loaded as seismic load.

Fig.4 Coulomb's earth pressure formula

For the section check with the seismic deformation method, the allowable stress method is used for normal time and level 1 earthquake, and the critical state method is used for level 2 earthquake. With the seismic coefficient method, all conditions are checked with the allowable stress method. The allowable value is same in level 1 and 2 earthquake.