Bus stop where the bench blocks the only level access
A Bengaluru bus stop occupies a 3.5 m wide footpath. Peak flow is 24 buses and about 140 boarding passengers an hour. The only furniture is a 2 m × 1 m concrete bench with no back and no roof. Users are roughly 30% office workers and elderly residents, 25% schoolchildren aged 8–14, 20% street vendors who set up beside the stop, and one regular wheelchair user who boards the low-floor bus from the kerb. Local norms require 1.5 m of clear footpath. The shelter cannot project more than 1.5 m from the building line. Monsoon rain is heavy from June to September; the western afternoon sun sits at 55–70° above the horizon. The residents' association wants a glass back panel for rain protection; the vendors want the sides left open; the wheelchair user says the bench currently blocks the only level approach to the kerb.
1. Resolve the bench versus wheelchair-access conflict with a specific layout, giving dimensions.
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Replace the single 2 m block with three 750 mm segments against the back wall, each 450 mm deep and 450 mm high, with 900 mm clear between segments, and keep a continuous 1.5 m band of footpath free in front of them.
The 900 mm gap is the governing dimension: wide enough for a wheelchair to pull in parallel to the kerb and transfer, and also wide enough for a queue to form without spilling into the planted strip. Place one gap directly opposite the kerb boarding point, because that is where the wheelchair user actually boards.
Seated length rises from 2 m to 2.25 m and access improves, so the association does not have to be argued out of seating to get access. The conflict was a siting error, not a furniture problem: nothing needs to be invented, only rearranged.
2. The glass back panel is requested for rain protection but the vendors want open sides. What is your decision, and what does it depend on?
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Glass to 900 mm, fully open above.
Up to 900 mm it keeps wind-driven rain off seated passengers' legs and bags, which is what the association is actually complaining about. Above 900 mm it would cut the vendors' sightline to the oncoming bus and to their own customers, and their livelihood depends on both.
This is a decision that should follow observation rather than preference: watch one full rain event and note where water lands on the bench, and watch whether the vendors stand behind or beside the shelter. If the rain arrives at 30–40° from the west, a 900 mm solid panel plus a 200 mm upstand on the roof's western edge does more than a full-height glass wall, needs less cleaning, and does not heat the waiting area like a greenhouse.
3. How would you choose between a flat cantilever roof and a curved roof within the 1.5 m depth limit?
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Choose by shadow, because sunlight is the constraint you can calculate and rain is the one you can only approximate.
With the roof edge at 2.4 m, a 60° sun altitude throws a shadow of about 1.4 m (2.4 ÷ tan 60°), so a 1.5 m flat cantilever just covers the bench at midday. At 70° the shadow shortens to about 0.87 m (2.4 ÷ tan 70°) and the outer half of the bench is in sun during the worst hour.
Build both as 1:20 card models, light them with a desk lamp set to 55° and 70° from the west, and photograph the shadow onto a plan. Pick whichever keeps about 80% of the seating shaded at 15:00 in April - the pre-monsoon month when people are most likely to be waiting in the open. Appearance is the tiebreaker only after that test.