diff --git a/src/views/newMap/newMapdraft/mapoperate/models.js b/src/views/newMap/newMapdraft/mapoperate/models.js
index 766b8ecb5..ae352df3f 100644
--- a/src/views/newMap/newMapdraft/mapoperate/models.js
+++ b/src/views/newMap/newMapdraft/mapoperate/models.js
@@ -54,6 +54,7 @@ class Model {
         this.rightAxleOffset = { x: 0, y: 0 };
         this.leftAxleOffset = { x: 0, y: 0 };
         this.logicLengthList = [];
+        this.relCrossSection = '';
     }
     SignalModel() {
         this._type = 'Signal';