Gate and Barricade Plan for a Two-Day Yatra
You are drafting a bandobast plan for a two-day yatra on an open ground measuring 120 m by 80 m. Day 1 expects 18,000 people; Day 2 expects 24,000. The event opens at 6 am and the main ritual is at 10 am. Experience says 40% of the day's crowd arrives in the first 90 minutes after opening. Each entry gate can process 500 persons per hour. One gate must be kept exclusively for emergency vehicles and women, and it will not process the general queue. The perimeter must be barricaded except for gate openings of 4 m each. Barricade panels are sold in 3 m lengths, and you must add a 10% wastage buffer. The control room asks for a gate count and a barricade panel count by this evening.
1. Calculate the minimum number of processing gates needed for Day 2 during the 90-minute surge, and the total gates including the reserved gate. Show every step.
Read the worked answer
Day 2 crowd = 24,000. Surge share = 40% = 0.40 × 24,000 = 9,600 persons. Surge window = 90 minutes = 1.5 hours. One processing gate handles 500 × 1.5 = 750 persons in that window. Required processing gates = 9,600 ÷ 750 = 12.8. Since a fraction of a gate cannot be used, round up to 13. Check: 13 × 750 = 9,750, which is above 9,600; 12 × 750 = 9,000, which is short. Add the reserved emergency/women gate: 13 + 1 = 14 total gates. The plan should state 14 gates, of which 13 process the general queue.
2. Calculate the barricade panels required. Use the full perimeter, subtract gate openings, add 10%, and round up to whole 3 m panels.
Read the worked answer
Perimeter = 2 × (120 + 80) = 2 × 200 = 400 m. Gate openings = 14 gates × 4 m = 56 m. Net barricade length = 400 − 56 = 344 m. Add 10% wastage: 344 × 1.10 = 378.4 m. Panels required = 378.4 ÷ 3 = 126.13. Round up to 127 panels. Check: 127 × 3 = 381 m, which covers 378.4 m with 2.6 m to spare. A plan that orders 126 panels would provide 378 m and fall 0.4 m short before any cutting loss, so 127 is the defensible figure.
3. If two processing gates become unusable at 6 am on Day 2, calculate the new clearance time for the 9,600 surge and state whether the plan still meets the 90-minute target. Give a practical judgement.
Read the worked answer
Remaining processing gates = 13 − 2 = 11. Capacity = 11 × 500 = 5,500 persons per hour. Time to clear 9,600 = 9,600 ÷ 5,500 = 1.745 hours, i.e. about 1 hour 45 minutes. The target was 1.5 hours, so the plan misses it by about 15 minutes. Judgement: do not quietly convert the reserved gate to general queue without arranging emergency cover; instead open a pre-designated overflow gate, hold the surge at the approach road, and announce staggered entry. The numbers show the shortfall is modest but real, so a spare gate or a holding area is needed, not a paper adjustment.