Domain: Engineering — Geotechnical Engineering
Target concept: Soil sample volume shows significant expansion and upward bulging

Video generation prompt: Place a suitable amount of dry expansive soil sample into a transparent container and slowly add water to moisten it.

Evaluation guide:
(i) Target concept: Hydration-induced volumetric expansion of expansive soil leading to upward bulging.
Minimum mechanism: Soil must be initially dry and cohesive; water must make direct contact; swelling must be vertical, progressive, and constrained by container walls to manifest as upward surface displacement.
(ii)Storyline: [Frame 0–2] Dry soil rests statically in bottom half of transparent container; [Frame 3–4] Water stream enters container from above and contacts soil surface; [Frame 5–7] Soil darkens locally at contact zone; [Frame 8–9] Soil surface begins rising upward as convex bulge, maintaining granular integrity; [Visibility constraint] Entire soil-water-container interface must remain fully visible, front-facing, with no occlusion or angle distortion; [Perspective constraint] Fixed frontal viewpoint, no rotation or tilt, container centered and upright.

Manual:
Experimental Procedure
1. Place dry expansive soil sample into a transparent container.
2. Slowly add water from above until soil is moistened.
Observation of Experimental Phenomena
Soil surface rises upward uniformly, forming convex bulge; volume visibly expands without cracking or flowing.
Summary of Experimental Principles
Expansive soils contain clay minerals (e.g., montmorillonite) that absorb water, swell, and generate significant upward pressure — key to geotechnical hazard assessment.

Prompt Grounding rubric:
level_1: No dry soil is shown in any container; no transparent container appears; no water is poured; the placement-then-watering setup described in the prompt is entirely absent.
level_2: A transparent container and a soil sample appear, but at least one required element is missing, or the container is not transparent (e.g. it is opaque, tinted, or covered by an opaque label blocking the view), or the soil already looks moist or wet before any water is added, or water is poured before the soil is placed, or no water is ever added.
level_3: Dry soil is placed into a transparent container, and water is subsequently poured onto it so the liquid visibly touches the soil surface, in that order (soil first, water second); the container stays upright and stationary; nothing unrelated to this setup is in frame.
level_4: The soil visibly looks dry before any water touches it (matte, light-colored, no wet sheen); the container is fully see-through with no obstruction blocking the soil-water interface; the water is poured from above directly into the container rather than from the side or from outside it; and the water level in the container rises without spilling over the rim or disappearing between shots.
level_5: Building on level 4: watering only begins once the soil has come to rest at the bottom of the container (it is not still being poured or settling when water starts); the soil sits below the container's midline before any water is added; the water arrives as one continuous pour rather than several separate splashes or drips; and the soil-water contact area stays unobstructed by hands, labels, or camera angle in every frame.

Scientific and Causal Correctness rubric:
level_1: The soil's top surface never rises after water is added — it stays flat or compact for the whole video, or the soil visibly shrinks, cracks apart, or dissolves into the water instead of swelling.
level_2: The soil darkens where water lands, showing it has absorbed moisture, but the surface stays level with no upward doming; or any surface change moves sideways or downward rather than up; or a bulge appears abruptly in a single instant rather than growing over time.
level_3: After water contacts it, the soil's surface visibly domes upward, forming a rounded bulge that grows over more than an instant; the bulge starts near the middle or spreads fairly evenly across the surface; the soil stays intact as a solid mass rather than turning into mud or flowing like a liquid.
level_4: In addition to level 3: the upward bulging keeps growing step by step rather than jumping to full size or resetting partway; the soil keeps its granular, clumped look rather than collapsing into slurry; the color change from dry/light to wet/dark spreads outward from where the water lands and appears before the bulge grows there, showing moisture visibly precedes swelling rather than the reverse; the bulge does not sink back down once it has risen.
level_5: In addition to level 4: the bulge keeps getting taller for as long as the video runs, without plateauing and shrinking back; the upward movement is confined to the soil itself (the container's rim or any lid stays put and undeformed); no soil overflows the container or breaks into separate cracked chunks; and individual soil grains or clumps stay visibly distinct at the surface rather than blurring into a smooth wet paste.

Spatiotemporal Consistency rubric:
level_1: The container jumps to a different position or camera angle between shots with no hand or camera motion shown carrying it there; the soil mass or the falling water stream vanishes and reappears elsewhere in frame; the container's outline warps or fractures unnaturally as the soil swells; the shot cuts or zooms with no soil-and-water action to justify the change.
level_2: The container appears to rock or slide as though unsupported, with nothing shown pushing or holding it; the water stream has a visible gap between where it should start (a pitcher, hose, or hand) and where it begins falling; soil grains appear to float above the surface with no contact; or the shadow the container and the rising soil bulge cast on the table swaps to the opposite side mid-video even though nothing about the room's lighting changes.
level_3: The container stays in the same spot with the same orientation for the whole clip; the soil stays inside the container's walls; the water stream flows in from a consistent direction throughout the pour; the shadow cast by the container and soil stays on the same side without flickering on and off; nothing in the shot fractures, warps, or freezes unnaturally.
level_4: Building on level 3: there is no jump in how far along the bulging looks from one moment to the next (it doesn't skip stages); the water's fall into the container looks like one continuous stream rather than stuttering or skipping; once bulging starts, it doesn't reverse or freeze mid-rise before continuing; the container's transparent walls show the same reflective/refractive look throughout rather than suddenly appearing more or less transparent.
level_5: Building on level 4: the water forms a visible meniscus where it meets the container wall and the soil, and this contact line moves smoothly rather than snapping between positions; the top of the rising soil bulge keeps a continuously curved profile as it grows rather than developing sudden flat facets or sharp corners; and the outline of the container rim stays a consistent, unbroken shape relative to the soil behind it throughout the pour and the swelling.