Reaction distance
reaction_distance_m
Reaction distance component d_r (m)
Scores if within ±3% of the reference value.
Computes stopping sight distance (SSD) on graded road segments as the sum of reaction distance d_r = V*t_r/3.6 and braking distance d_b = V^2/(254*(f+g)), using speed-dependent longitudinal friction coefficients from AGRD Part 3 Table 5.5. Accounts for uphill and downhill grades to verify geometric design adequacy for safe vehicle stopping.
with-tool: The model is given an executable Python calculator script.
Standards
One template produces many comparable benchmark tasks while keeping the scoring contract fixed.
01
The reusable contract shown on this page.
02
An archetype and site context are sampled.
03
Inputs may be hidden at harder tiers.
04
The model responds with the declared outputs.
Inputs the model receives, and the outputs it is scored on.
3 inputs
Included directly in every task prompt.
Design speed
design_speed_km_h
Design speed V
Grade pct
grade_pct
Longitudinal grade (positive = uphill, negative = downhill)
Visible in easier tasks and withheld in one or more harder tiers.
Reaction time
reaction_time_s
Driver reaction time t_r
Hidden at hard difficulty.
3 outputs
reaction_distance_m
Reaction distance component d_r (m)
Scores if within ±3% of the reference value.
braking_distance_m
Braking distance component d_b (m)
Scores if within ±3% of the reference value.
stopping_sight_distance_m
Total stopping sight distance SSD (m)
Scores if within ±3% of the reference value.
Each template is sampled at three tiers. Harder tiers may hide inputs, forcing the model to infer them from the scenario description.
All inputs given
All parameters given, flat to gentle grade on a suburban arterial
All inputs given
All parameters given, any road type including steep grades
Some inputs hidden
Reaction time hidden — agent must infer t_r from road type and driver alertness context
Hidden inputs
Prompt replacement text
The site is a {{ archetype.description }} ({{ archetype.site_context }}). Assume an appropriate driver reaction time for this road environment.
The exact instruction and parameter contract used to generate this task, pinned to the published library source.
/workspace
Teal lines show Jinja input conditions, not task visibility policy. A line renders only when that input or tool is visible.
1You are a senior civil engineer specializing in road geometry and stopping sight distance analysis.2 3## Problem4 5Calculate the required stopping sight distance (SSD) for a road segment on a longitudinal grade.6 7## Given8 9| Parameter | Value | Unit |10|-----------|-------|------|11| Design speed (V) | {{ design_speed_km_h }} | km/h |12| Longitudinal grade | {{ grade_pct }} | % |13{% if reaction_time_s is defined %}14| Reaction time (t_r) | {{ reaction_time_s }} | s |15{% endif %}16{% if archetype_description is defined %}17 18### Site Conditions19 20{{ archetype_description }}21{% endif %}22 23{% if tool_available %}24## Available Tool25 26A stopping sight distance calculation tool is available at `/workspace/{{ meta.name }}_calc.py`. Run it with:27 28```bash29python3 /workspace/{{ meta.name }}_calc.py --help30```31 32You may use this tool to verify your calculations or compute values directly.33{% endif %}34 35## Required36 37Calculate the following:38 391. Reaction distance component d_r (m)402. Braking distance component d_b (m)413. Total stopping sight distance SSD (m)42 43## Applicable Standards44 45- Austroads Guide to Road Design Part 3 (AGRD Part 3 §5)46 47## Constraints48 49- No internet access is available. Work from engineering knowledge and the provided tool.50- The friction coefficient f depends on design speed per AGRD Table 5.5. Use the following lookup:51 - 40 km/h → f = 0.52, 50 → 0.48, 60 → 0.45, 70 → 0.43, 80 → 0.40, 90 → 0.38, 100 → 0.36, 110 → 0.34, 120 → 0.32, 130 → 0.2952 - Interpolate linearly for intermediate speeds53- Reaction distance: d_r = V × t_r / 3.6 (where V in km/h, t_r in seconds)54- Braking distance: d_b = V² / (254 × (f + g)) (where g = grade / 100, positive = uphill)55 - Sign convention: positive grade means uphill travel (grade assists braking); negative grade means downhill travel (grade hinders braking)56- Total SSD = d_r + d_b57{% if reaction_time_s is not defined %}58- Reaction time is not provided; select an appropriate value based on the road environment and expected driver alertness. AGRD recommends 1.5 s (alert) to 2.5 s (relaxed).59{% endif %}60 61## Output Format62 63Show your step-by-step working in Markdown. At the end of your solution, include a JSON block with your final answers in exactly this format:64 65```json66{67 "reaction_distance_m": <numeric_value>,68 "braking_distance_m": <numeric_value>,69 "stopping_sight_distance_m": <numeric_value>70}71```72 73Write your complete solution to `/workspace/output.md`.74 Each generated task is drawn from one of these realistic scenario bands.
Site contexts ground each scenario in a real locale the model can use to infer hidden values.
urban_local_street
Low-speed urban local street with pedestrian activity and on-street parking
suburban_arterial
Suburban arterial road with moderate speeds and intersection access
rural_highway
Rural two-lane highway through open terrain with higher operating speeds
mountain_road
Winding mountain road with steep grades and limited sight lines
sydney-pennant-hills-road-suburban-arterial-preview — hard difficulty, some inputs hidden.
Suburban arterial road with moderate speeds and intersection access. sydney-pennant-hills-road. Required outputs: reaction_distance_m, braking_distance_m, stopping_sight_distance_m
Scenario context and visible inputs.
Executable tool: ssd-on-grade_calc.py
Inputs withheld at this difficulty.
Reaction time s
reaction_time_s
Stand-in text in the prompt
The site is a {{ archetype.description }} ({{ archetype.site_context }}). Assume an appropriate driver reaction time for this road environment.
The scored JSON answer schema.
{
"reaction_distance_m": <number>,
"braking_distance_m": <number>,
"stopping_sight_distance_m": <number>
}