Box Culverts - Difference between ASTM C1433 and C1577

[JoelTXCive]

Is there a quick easy definition for the difference between C1433 culverts and C1577 culverts?

It looks to me like the C1433 culverts take an HS-20 load with a 24Kip 'design tandem load'.

Whereas the C1577 takes the HL-93 model (Comprised of HS-20 + 25kip design tandem).

Neither standard takes the design lane load.

Is this a good summary? If so, then why two standards. I must be missing something.

Thank you,

Joel

 

[le99]

The ASTM Standard for the Standard Design Code is: ASTM C 1433 Precast Reinforced Concrete Monolithic Box Sections for Culverts, Storm Drains, and Sewers

The ASTM Standard for the LRFD Design Code is: ASTM C 1577 Precast Reinforced Concrete Monolithic Box Sections for Culverts, Storm Drains, and Sewers According to AASHTO LRFD

Also, you may find a note on the AASHTO standards M 259 and M 273 - “If load–and-resistance factor design is required, then use ASTM C 1577.”

 

[JStructsteel]

Pretty much all states have gone to LRFD with HL93 as the design truck

 

[JoelTXCive]

I thought we always spec'd the C1577 ones, but we have an existing project's specifications that has 1 region of culverts citing the C1433 standard in our contract documents.

I think it was old contract language that somehow slipped by. We are trying to determine if we can keep the C1433 standard; or need to issue a change order to the 1577 standard.

 

[le99]

I think it is better to keep your spec consistent with the design code, so as not to cause confusion.