Domain: Engineering — Structural Engineering
Target concept: Mortar Strength and Seismic Resistance

Video generation prompt: Two masonry structure models are displayed side by side on the table. The model on the left has a mortar strength of M5, while the model on the right has a mortar strength of M10. Low-cycle cyclic loading is applied until one of them is damaged.

Evaluation guide:
(i) Target concept: Mortar strength governs masonry structure"s resistance to low-cycle cyclic loading, with higher strength delaying joint cracking and collapse.
Minimum mechanism: Load must be applied cyclically (repeated compression-tension), damage must initiate preferentially in lower-strength mortar (M5), and failure must manifest as mortar-joint cracking or localized collapse, not unit fracture or global instability.
(ii)Storyline: Frame 1–2: Static wide shot showing two labeled models side-by-side on table. Frame 3–4: Loading apparatus makes firm contact with both models. Frame 5–7: Apparatus executes ≥2 full oscillations with visible displacement. Frame 8–9: Cracks appear *only* in M5 model"s mortar joints during loading phase; M10 model shows zero joint separation. Frame 10: Final state shows M5 with open cracks and minor spalling, M10 fully intact. Perspective: Fixed frontal view, eye-level, no occlusion, full models and labels always in frame.

Manual:
Experimental Procedure
1. Place two identical masonry structure models side-by-side on a rigid table.
2. Label left model “M5”, right model “M10”.
3. Attach low-cycle cyclic loading apparatus to top surfaces of both models.
4. Apply symmetric back-and-forth loading until visible structural damage occurs in one model.
Observation of Experimental Phenomena
The M5-labeled model develops visible cracking along mortar joints and partial wall panel collapse, while the M10-labeled model remains fully intact with no cracking or deformation.
Summary of Experimental Principles
Higher mortar strength (M10 vs M5) increases bond strength and compressive resistance, improving seismic performance by delaying crack initiation and maintaining structural integrity under cyclic lateral loads.

Prompt Grounding rubric:
level_1: No masonry model appears, or only one model is shown, or the two models are never both on the table at the same time, or neither model bears a visible label distinguishing M5 from M10, or no loading apparatus is shown.
level_2: Both masonry models and a loading apparatus appear, but the models are stacked, overlapping, or separated by a wide gap rather than sitting side by side on the table, or it is unclear which model is on the left versus the right, or the apparatus never touches either model.
level_3: Both models sit side by side on the table within the same shot; the left model is marked or otherwise identifiable as M5 and the right model as M10; the loading apparatus visibly presses against both models, either together or one after the other.
level_4: The left model (M5) and right model (M10) sit side by side on the table, correctly labeled, and the loading apparatus visibly pushes back and forth against both in a repeating cyclic motion while the models stay in place until damage appears; no object blocks the view of either model or its label.
level_5: The two models sit in a strictly horizontal, symmetric side-by-side arrangement, matched in size, shape, and material appearance apart from their labeled mortar grade; the loading apparatus applies its back-and-forth motion to the top of both models at the same time; the camera holds one fixed frontal view with no zoom or repositioning for the entire clip.

Scientific and Causal Correctness rubric:
level_1: Neither model shows any damage, or both models crack or collapse at the same time, or damage appears before the loading apparatus starts moving, or the visible change is cosmetic only (paint flaking or color change) rather than structural cracking.
level_2: Only the M5 model is damaged, and the damage begins after loading starts, but the failure mode is unrealistic for masonry (for instance the model crumbles entirely to dust or bursts apart explosively), or the damage instead appears in the M10 model.
level_3: The M5 model develops visible cracking or a partially collapsed wall section while the M10 model stays intact, and this damage appears only after the loading apparatus has been moving for at least two full back-and-forth cycles.
level_4: The M5 model's cracking runs along the mortar joints between bricks (not through the bricks themselves) while the M10 model shows no joint opening or brick misalignment at any point, and M10 never fails before M5 does.
level_5: The M5 model's mortar-joint cracks visibly widen during each compression stroke and partially close during each tension stroke, ending permanently open after the final cycle, while the M10 model keeps its joints fully tight and shows no hairline cracking or surface separation throughout.

Spatiotemporal Consistency rubric:
level_1: One of the two models suddenly appears in a different spot with no motion in between, or a chunk of a model vanishes and reappears, or the loading apparatus flashes to a new position, or the table surface visibly warps between frames, or the lighting abruptly flashes or flips between bright and dark with no source change to explain it.
level_2: A model briefly disappears due to a jump or skipped frame, the edge of a model visibly warps or bends across several consecutive frames, the shadow cast by a model points a different way with no change in lighting, or the loading apparatus moves in a jerky, stop-start manner instead of smoothly.
level_3: The two models stay on the table and the labels stay attached to the correct model, the apparatus keeps steady contact with the models, and no part of either model tears, clips through the other, or warps, but the light on the models shifts slightly in brightness or angle at one point in the clip.
level_4: The loading apparatus swings back and forth with a steady, even rhythm and consistent range of motion, the edges of both models line up consistently from one frame to the next, the camera holds its position with no drift, and no crack is shown appearing before the apparatus makes contact.
level_5: The mortar joints and brick edges on both models stay visually steady and well-defined in every frame with no blurring that hides the joint lines, both models look equally sharp and equally lit throughout (neither looks closer or farther than the other), and the overall brightness of the scene stays even from frame to frame.