Extract sum shear force logic

StructureHelperLogics/Models/BeamShears/Logics/IGetDirectShearForceLogic.cs

@@ -0,0 +1,17 @@
+using StructureHelperCommon.Infrastructures.Interfaces;
+using StructureHelperCommon.Models.Forces;
+
+namespace StructureHelperLogics.Models.BeamShears
+{
+    /// <summary>
+    /// Implements logic of calculating shear force without considering term and limit state
+    /// </summary>
+    public interface IGetDirectShearForceLogic : ILogic
+    {
+        /// <summary>
+        /// Returns value of shear force at the end of inclined section
+        /// </summary>
+        /// <returns>Value of shear force at the end of inclined section</returns>
+        double CalculateShearForce();
+    }
+}