diff --git a/repository/physical_section.go b/repository/physical_section.go
index f9a19c1..8244e06 100644
--- a/repository/physical_section.go
+++ b/repository/physical_section.go
@@ -3,8 +3,8 @@ package repository
 import (
 	"errors"
 	"fmt"
-
 	"joylink.club/rtsssimulation/repository/model/proto"
+	"joylink.club/rtsssimulation/util/number"
 )
 
 // 物理区段
@@ -30,10 +30,7 @@ type PhysicalSection struct {
 	//aKm/bKm对应的LinkPosition
 	aLinkPosition *LinkPosition
 	bLinkPosition *LinkPosition
-	////在Link上的区间（根据aKm和bKm计算出的，start的offset一定小于end的offset）
-	//startLinkPosition *LinkPosition
-	//endLinkPosition   *LinkPosition
-	//在Link上的区间
+	//在Link上的区间（start小于end）
 	linkRanges []*LinkRange
 
 	//物理区段所属集中站
@@ -46,6 +43,14 @@ func NewPhysicalSection(id string) *PhysicalSection {
 	}
 }
 
+func (p *PhysicalSection) bindLinkRange(link *Link, one int64, two int64) {
+	p.linkRanges = append(p.linkRanges, &LinkRange{
+		link:  link,
+		start: number.Min(one, two),
+		end:   number.Max(one, two),
+	})
+}
+
 func (s *PhysicalSection) PortNum() int {
 	return 2
 }
diff --git a/repository/repository_manager.go b/repository/repository_manager.go
index 0163bf9..731fc68 100644
--- a/repository/repository_manager.go
+++ b/repository/repository_manager.go
@@ -686,11 +686,7 @@ func relatePhysicalSectionAndLink(repo *Repository, section *PhysicalSection, li
 		link:   link,
 		offset: bOffset,
 	}
-	section.linkRanges = append(section.linkRanges, &LinkRange{
-		link:  link,
-		start: aOffset,
-		end:   bOffset,
-	})
+	section.bindLinkRange(link, aOffset, bOffset)
 }
 
 func getATurnoutPort(turnouts []*Turnout, visitedTurnoutMap map[string]bool) *TurnoutPort {
@@ -764,31 +760,19 @@ func buildLinkRangeOfTurnoutPhysicalSection(link *Link) {
 	//解决[两道岔的道岔物理区段，两道岔间的Link会产生两个LinkRange]的问题
 	if link.aRelation != nil && link.bRelation != nil && link.aRelation.turnout.section == link.bRelation.turnout.section {
 		section := link.aRelation.turnout.section
-		section.linkRanges = append(section.linkRanges, &LinkRange{
-			link:  link,
-			start: 0,
-			end:   link.length,
-		})
+		section.bindLinkRange(link, 0, link.length)
 		return
 	}
 
 	if link.aRelation != nil {
 		aSection := link.aRelation.turnout.section                                          //Link A端的关联的道岔物理区段
 		aLinkPosition := link.aRelation.turnout.FindLinkPositionByPort(link.aRelation.port) //Link A端道岔端点在Link上的位置
-		aSection.linkRanges = append(aSection.linkRanges, &LinkRange{
-			link:  link,
-			start: 0,
-			end:   aLinkPosition.offset,
-		})
+		aSection.bindLinkRange(link, 0, aLinkPosition.offset)
 	}
 	if link.bRelation != nil {
 		bSection := link.bRelation.turnout.section                                          //Link A端的关联的道岔物理区段
 		bLinkPosition := link.bRelation.turnout.FindLinkPositionByPort(link.bRelation.port) //Link A端道岔端点在Link上的位置
-		bSection.linkRanges = append(bSection.linkRanges, &LinkRange{
-			link:  link,
-			start: link.length,
-			end:   bLinkPosition.offset,
-		})
+		bSection.bindLinkRange(link, bLinkPosition.offset, link.length)
 	}
 }