Domain: Engineering — Structural Engineering
Target concept: A centrally loaded column is uniformly compressed and has a higher load-bearing capacity.

Video generation prompt: Place two concrete columns side by side on a table and apply the same vertical load to both. The left concrete column is subjected to axial compression, while the right concrete column is subjected to eccentric compression. Gradually increase the vertical load until deformation or failure occurs in the concrete columns.

Evaluation guide:
(i) Target concept: Axial vs. eccentric compressive stability in slender concrete columns.
Minimum mechanism: Columns must be slender enough for the eccentric load to produce a noticeable bending moment (P-delta effect) rather than pure crushing; concrete is treated as the brittle/quasi-brittle compressive material it actually is: progressive surface micro-cracking culminating in sudden crushing or spalling, not a ductile elastic-plastic bending phase; load must be applied statically and monotonically; supports must let the eccentrically loaded column deflect laterally rather than being fully clamped.
(ii)Storyline: Frame 1–2: Static wide shot showing two identical concrete columns side-by-side on table, no load. Frame 3–4: Load application begins. Identical downward motion from above onto both columns. Frame 5–7: Left column shortens vertically with no lateral motion; right column develops progressive lateral curvature while shortening. Frame 8–9: Right column's curvature increases, visible cracking appears on outer convex face; left column remains perfectly straight. Frame 10: Right column collapses/buckles; left column remains intact and upright. Viewpoint: Fixed frontal orthographic-like framing, full columns in view, no occlusion, consistent lighting from upper front.

Manual:
Experimental Procedure
1. Place two identical gray concrete columns side by side on a flat horizontal table.
2. Apply identical vertical downward loads simultaneously to both columns from directly above.
3. Increase load gradually until deformation or failure occurs.
Observation of Experimental Phenomena
Left column remains straight and compresses uniformly; right column bends laterally while shortening, then fails earlier via buckling or asymmetric cracking.
Summary of Experimental Principles
Axially loaded columns resist higher loads due to uniform stress distribution; eccentrically loaded columns experience bending moment + compression, reducing load capacity and causing instability.

Prompt Grounding rubric:
level_1: No concrete columns are present; or only one column is shown; or the two columns are not placed side by side on a flat horizontal surface; or no vertical load application is visible; or a load is applied to only one column; or a load is applied at an angle or horizontally instead of vertically.
level_2: Two column-like objects sit side by side on a flat surface, but at least one setup element is missing: both are not clearly concrete-colored (grayish, coarse-textured); or the vertical load is not applied to both at the same time; or the load contact is not a clearly downward press (plate, weight, or hand) from above; or the two load-contact points look identical, with no visible difference in where the load touches each column's top face.
level_3: Two grayish, coarse-textured concrete columns of matching size sit side by side on a flat horizontal surface; a vertical load is applied to both from directly above using a consistent method (e.g., identical weights, pressing plates, or hand motions); the load contacts the left column's top face at its center; the load contacts the right column's top face clearly off-center, toward one edge; neither column is tilted, overlapping, or floating before loading starts.
level_4: Everything in score 3 holds, and in addition the off-center location of the load contact on the right column stays at the same edge/offset each time the load is renewed or increased, rather than drifting toward the center or to a different side; the base position of each column on the surface does not shift; the camera stays static and frontal, keeping both columns fully visible without cuts or occlusion.
level_5: Everything in score 4 holds, and in addition both columns keep their original concrete texture, color, and scale for the entire clip (no material swap, relighting, or rescaling); the centered contact point on the left column and the off-center contact point on the right column remain the only visible difference in how the load is delivered to the two columns; and there is no camera cut, repositioning, or change of zoom or angle at any point, including during any deformation or failure event.

Scientific and Causal Correctness rubric:
level_1: The setup contradicts axial vs. eccentric compression: both columns deflect identically; the left (axial) column deflects more than the right (eccentric) column; both columns fail in the same symmetric crushing mode; or failure occurs with no visible deformation beforehand.
level_2: At least one column deforms, but not in the way the loading type predicts: the left column shows lateral bending; the right column shows only straight vertical shortening with no bending; deformation appears before any load is applied; or both columns fail explosively/suddenly with no visible progressive bending in the right column beforehand.
level_3: The left column stays straight and upright through loading while the right column visibly bends laterally (develops curvature or leans off the vertical axis) as loading proceeds; both columns shorten somewhat, but only the right column changes shape asymmetrically (bending plus shortening); if failure is shown, it occurs first in the right column as buckling or cracking on its convex face.
level_4: Everything in score 3 holds, and in addition the right column's lateral bending begins before any visible cracking or crushing appears in either column; the left column shows no lateral deviation at any point, even at the highest load shown; the right column's bending stays consistently oriented toward one side rather than oscillating or reversing direction.
level_5: Everything in score 4 holds, and in addition the right column's lateral bending increases steadily (no pause or reduction) as load increases; the left column shows no visually perceptible tilt, lean, or curvature away from vertical (however slight) even under the highest load; the right column's failure is a localized buckling or diagonal/shear crack aligned with the side it bent toward, not a uniform crushing across its whole cross-section.

Spatiotemporal Consistency rubric:
level_1: A column vanishes or is suddenly replaced between frames with no visible motion causing it; a column's position jumps without any sliding or lifting shown; the lighting swings abruptly from bright to dark (or the reverse) between adjacent frames; the load (plate/weight/hand) appears or disappears without any approach or withdrawal motion; or a column visibly warps, melts, or breaks apart in a way concrete cannot.
level_2: A column jitters or wobbles with no applied force visible; the load's downward motion jump-cuts rather than moving continuously; the shadows the two columns cast switch sides relative to each other between frames even though the light source hasn't moved; a column appears to pass partway through the table surface; or the table surface visibly sags or flexes under the static load in a way rigid concrete and a table would not.
level_3: A brief, isolated jitter appears at a column's base while load is being applied; the view of a column is very briefly and only partially blocked during loading; the shadows on the bench shift very slightly and briefly at one point in the clip; one instance of the load-application tool relocating without a visible path between positions; none of these persist, and there is no vanishing, teleporting, or breaking apart of either column.
level_4: Everything in score 3 holds, and in addition the two columns stay the same distance apart and do not slide or shift on the table at any point; the load is applied with smooth, continuous motion with no jumps, freezes, or stutters; the shadows both columns cast keep the same direction and length as the clip progresses; the table surface stays flat and rigid, without sagging or flexing.
level_5: Everything in score 4 holds, and in addition neither column shows any visible shaking or vibration at rest or during loading; the load-application motion keeps a constant speed with no sudden jerks; the edges and surface texture of both columns stay clearly defined and stable across every frame; the shadow geometry and any surface reflections stay coherent and unchanging over time; and neither column appears to shift relative to the other in a way that would suggest the camera itself moved.