diff --git a/B05_Profile/B05_Profile_UI_Corridor_Plan.ts b/B05_Profile/B05_Profile_UI_Corridor_Plan.ts
index a97adaa7..af223076 100644
--- a/B05_Profile/B05_Profile_UI_Corridor_Plan.ts
+++ b/B05_Profile/B05_Profile_UI_Corridor_Plan.ts
@@ -19,6 +19,8 @@ import type { CrossSection } from "../B06_Section/B06_Section_Api_Fetch";
 import type { CorridorStructure, RouteFrame } from "./B05_Profile_UI_Corridor_Structures";
 import { structureSilhouettes } from "./B05_Profile_UI_Corridor_Station_Structure";
 import { assembleStripLoops, CarveFootprint, ringEdges } from "./B05_Profile_UI_Corridor_Carve";
+import { mixedGround, trimSlopeToGround } from "./B05_Profile_UI_Corridor_Station";
+import { groundInterpolator } from "../B06_Section/B06_Section_UI_Cross_Culvert_Solve";
 import type { PXY } from "./B05_Profile_UI_Corridor_Union";
 
 export type PlanCurveSource = "structure" | "slope-deformed" | "slope-original";
@@ -40,7 +42,7 @@ export interface PlanCurve {
 const PLANE_LIFT_M = 5;
 
 /** 비탈 스트립 종방향 걸음(m). */
-const STEP_M = 1.0;
+const STEP_M = 0.5;
 
 /** 안팎 폭이 이만큼은 돼야 커브를 만든다(m). */
 const MIN_WIDTH_M = 0.05;
@@ -62,6 +64,30 @@ interface PlanFrame {
   leftY: number;
 }
 
+/** 누가거리 → 그 행의 지반선. 인접 두 측점 지반을 섞는다(코리도 빌드와 같은 방식). */
+function buildGroundAt(
+  crossSections: ReadonlyArray<CrossSection>,
+): (chainageM: number) => ((offset: number) => number) | null {
+  const rows = crossSections
+    .map((section) => ({
+      chainage: section.chainage_m,
+      ground: groundInterpolator(section.samples),
+    }))
+    .sort((a, b) => a.chainage - b.chainage);
+  return (chainageM) => {
+    if (!rows.length) return null;
+    for (let i = 0; i < rows.length - 1; i += 1) {
+      const lo = rows[i];
+      const hi = rows[i + 1];
+      if (chainageM < lo.chainage || chainageM > hi.chainage) continue;
+      const span = hi.chainage - lo.chainage;
+      const t = span > 1e-6 ? (chainageM - lo.chainage) / span : 0;
+      return mixedGround(lo.ground, hi.ground, t);
+    }
+    return chainageM <= rows[0].chainage ? rows[0].ground : rows[rows.length - 1].ground;
+  };
+}
+
 function at(frame: PlanFrame, offset: number): PXY {
   return { x: frame.cx + frame.leftX * offset, y: frame.cy + frame.leftY * offset };
 }
@@ -165,6 +191,7 @@ export function buildPlanCurves(
   outline: CorridorOutline,
 ): PlanCurve[] {
   const curves: PlanCurve[] = [];
+  const groundAt = buildGroundAt(crossSections);
   for (const section of crossSections) {
     const set = structures.filter(
       (structure) => Math.abs(structure.chainage_m - section.chainage_m) < 1e-6,
@@ -213,30 +240,41 @@ export function buildPlanCurves(
       const side = silhouette.side;
       const sign = side === "left" ? 1 : -1;
       const roadEdge = roadEdgeOf(side);
-      // 변형 실루엣 — [노견 확장끝 → 실루엣 바깥끝].
+      // 변형 실루엣 — [노견 확장끝 → 실루엣이 그 행 지반과 만나는 자리].
+      // 실루엣은 소유 측점 단면 한 장이라 그대로 밀면 구간 내내 같은 폭이 된다
+      // (2026-08-26 사용자 ②) — 행마다 지반선에 트림해 실제 발끝을 따라가게 한다.
+      // 서피스는 여전히 안 건드린다 — 표기 커브만 바뀐다.
       const inner = silhouette.widenTo?.offset_m ?? roadEdge;
-      let outer = inner;
-      for (const point of silhouette.points) {
-        if ((point.offset_m - outer) * sign > 0) outer = point.offset_m;
-      }
       const from = section.chainage_m - silhouette.span.beforeM;
       const to = section.chainage_m + silhouette.span.afterM;
-      if ((outer - inner) * sign > MIN_WIDTH_M) {
-        const steps: number[] = [];
-        for (let atM = from; atM < to; atM += STEP_M) steps.push(atM);
-        steps.push(to);
-        push(
-          "slope-deformed",
-          side,
-          stripLoops(
-            steps.map((atM) => {
-              const frame = frameOf(atM);
-              return [at(frame, inner), at(frame, outer)] as [PXY, PXY];
-            }),
-            planZ,
-          ),
-        );
+      // "auto" = 실루엣 가운데가 지반보다 높으면 성토, 낮으면 절토(패치 리본과 같은 판정).
+      let kind: "cut" | "fill" = silhouette.kind === "auto" ? "fill" : silhouette.kind;
+      if (silhouette.kind === "auto") {
+        const stationGround = groundInterpolator(section.samples);
+        const mid = silhouette.points[Math.floor(silhouette.points.length / 2)];
+        if (stationGround && mid.elevation_m < stationGround(mid.offset_m) - 0.05) kind = "cut";
       }
+      const baseZ = frameOf(section.chainage_m).designZ;
+      const steps: number[] = [];
+      for (let atM = from; atM < to; atM += STEP_M) steps.push(atM);
+      steps.push(to);
+      const deformedRows = steps.map((atM): [PXY, PXY] | null => {
+        const frame = frameOf(atM);
+        const ground = groundAt(atM);
+        if (!ground) return null;
+        // 종단 경사만큼 실루엣을 통째로 올리고 내린다 — 측점 단면은 그 측점 계획고 기준이다.
+        const shift = baseZ != null && frame.designZ != null ? frame.designZ - baseZ : 0;
+        const placed = silhouette.points.map((point) => ({
+          offset_m: point.offset_m,
+          elevation_m: point.elevation_m + shift,
+        }));
+        const trimmed = trimSlopeToGround(placed, kind, ground);
+        if (!trimmed) return null;
+        const outer = trimmed[trimmed.length - 1].offset_m;
+        if ((outer - inner) * sign <= MIN_WIDTH_M) return null;
+        return [at(frame, inner), at(frame, outer)];
+      });
+      push("slope-deformed", side, stripLoops(deformedRows, planZ));
       // 원본 성토·절토선 — [노견 끝 → 코리도 바깥 윤곽(catch)]. 구조물이 없다고 본 면이다.
       const rows: Array<[PXY, PXY] | null> = [];
       outline.chainages.forEach((chainageM, index) => {