Examkin

Soru

Zorluk: Çok zorCargo Securement: Tie-Down Rules and WLL

An unblocked precast concrete pillar measuring 24 feet24\text{ feet} in length and weighing 54000 pounds54{}000\text{ pounds} is loaded onto a flatbed trailer. The cargo is currently secured with a single heavy-duty chain assembly possessing a verified Working Load Limit (WLL) of 6000 pounds6{}000\text{ pounds}. The driver intends to use identical synthetic web straps, each rated at a 5000-pound5{}000\text{-pound} WLL, for all remaining securement.

Under FMCSA regulations, what is the absolute minimum number of these synthetic straps that must be added to bring the securement system into full compliance?

  1. A
    2
  2. B
    3
  3. 5Cevap
  4. D
    6

Cevap

5
To be compliant, the securement system must satisfy both the length rule and the weight rule. While the length rule for a 24-foot24\text{-foot} unblocked article only necessitates 33 to 44 total tie-downs, the weight rule is much stricter for this heavy cargo. The aggregate WLL must equal at least 50%50\% of the cargo's weight, which is 27000 lbs27{}000\text{ lbs} (54000÷254{}000 \div 2). Because one chain providing 6000 lbs6{}000\text{ lbs} of WLL is already in place, the driver must make up the remaining 21000 lbs21{}000\text{ lbs} using the synthetic straps. Dividing the 21000 lbs21{}000\text{ lbs} deficit by the 5000-pound5{}000\text{-pound} capacity of each strap yields 4.24.2. Because fractions of a strap are impossible, the driver must round up and apply 55 additional straps.

Adım Adım Çözüm

1
Calculate the required aggregate Working Load Limit (WLL) based on cargo weight.
The minimum required WLL is 27000 pounds27{}000\text{ pounds}.
Federal regulations mandate that the combined WLL of all securement devices must be at least 50%50\% of the total cargo weight (54000×0.50=2700054{}000 \times 0.50 = 27{}000).
2
Determine the remaining WLL deficit after accounting for existing securement.
The remaining WLL deficit is 21000 pounds21{}000\text{ pounds}.
The driver has already applied one chain with a 6000-pound6{}000\text{-pound} WLL. Subtracting this from the required total (27000−600027{}000 - 6{}000) leaves the balance that must be covered by new straps.
3
Calculate the number of synthetic straps needed to cover the WLL deficit.
The driver needs 55 additional synthetic straps.
Divide the deficit by the strap rating: 21000÷5000=4.221{}000 \div 5{}000 = 4.2. Since partial straps cannot be used, this must be rounded up to the next whole number (55).
4
Verify if the number of straps satisfies the length-based tie-down rules.
The length rule is satisfied by default.
A 24-foot24\text{-foot} unblocked article requires a minimum of 33 or 44 tie-downs (depending on calculation method). The driver will be using a total of 66 securement devices (11 chain + 55 straps), easily exceeding the length minimums. The WLL is the limiting factor.

Anahtar Kavram

Cargo Securement: Tie-Down Rules and WLL
Bu soruyu puanla

Konular

Cargo Securement: Tie-Down Rules and WLL

Bu konudan daha fazla soru