b) A major road is to be upgraded and realigned. Following the completion of the works, it is expected that traffic will
Posted: Wed Apr 27, 2022 2:44 pm
- B A Major Road Is To Be Upgraded And Realigned Following The Completion Of The Works It Is Expected That Traffic Will 1 (83.9 KiB) Viewed 32 times
b) A major road is to be upgraded and realigned. Following the completion of the works, it is expected that traffic will transfer to the improved road from other parallel routes. The predicted vehicle flows and speeds before and after the improvements are presented in Table 1. The realignment is such that properties fronting on to the road, which were previously 30m away from the traffic stream, will now be 10m closer to traffic. Table 1: Flows and speeds before and after the road improvement Light vehicle Heavy vehicle Average traffic flow (0600- flow (0600 - speed km/h 2400) 2400) Before 40,000 6,000 50 improvement After improvement 42,000 9,000 65 i) Explain what is meant by the terms LA10, 18hr and Laeq, 18hr- A monitoring station has recorded the following noise levels at different times of the day: Day time (0600 – 1800) 72 dB(A) Laeq Evening time (1800 - 2400) 62 dB(A) LAeg Night time (2400 - 0600) 54 dB(A) LA Use the formula below to estimate the Laeq, 24hr at the monitoring station: i=n 0.1L degi Σι.10.17 i=1 T LAeq = 10log 10 where, 't' is the duration of measurement period i, 'LAeq, r is the level recorded in that period and 'T' is the duration of all periods combined.