It is proposed to widen and strengthen an existing two lane NH section...
To compute the cumulative standard axles (msa) for the proposed highway, you need to first calculate the design traffic volume for the highway. The design traffic volume is the expected traffic volume on the highway over its design life, which in this case is 10 years. The design traffic volume can be calculated using the following formula:
Design traffic volume = (existing traffic volume + (traffic growth rate * existing traffic volume * design life)) * traffic distribution factor
Plugging in the given values, we get: Design traffic volume = (2500 + (8% * 2500 * 10)) * 0.75 = (2500 + 2000) * 0.75 = 4500 * 0.75 = 3375
Next, we need to calculate the number of standard axles that the highway will experience over its design life. The number of standard axles can be calculated using the following formula:
Number of standard axles = design traffic volume * vehicle damage factor
Plugging in the values, we get: Number of standard axles = 3375 * 3.5 = 11737.5
Finally, we can calculate the cumulative standard axles (msa) for the highway using the following formula:
Cumulative standard axles (msa) = number of standard axles * design CBR
Plugging in the values, we get: Cumulative standard axles (msa) = 11737.5 * 5% = 586.875
Rounding this value to the nearest whole number gives us 587 cumulative standard axles (msa).
Therefore, the correct answer is 1, "65."