## General Mechanical

Topics relate to Mechanical Enterprise, Motion, Additive Print and more

#### Autodyn

• AhmedKhalil2011
Subscriber

Hi,

My case study is a concrete-filled tube column subjected to a contact explosion and the compression strength of the concrete is 35 Mpa I used the RHT model for concrete.

My question is: Is it normal to have stress 4000 MPa at the concrete particles in front of the explosion?

• Chris Quan
Ansys Employee

Is the stress of 4000 MPa a tensile stress or a compressive stress?

You need to look at pressure in the concrete to see how large the pressure is at tthe same location.

If the stress of 4000 MPa is negative, it is from pressure. The magnitude may be reasoanble.

If the stress of 4000 MPa is positive, you need to check the material model to make sure it has failure criteria to limit its maximum tensile stress.

• AhmedKhalil2011
Subscriber

Thanks, Chris Quan

The stress in concrete is compressive; its value is 4000 MPa and the pressure at the same location is 3832 MPa.

I know that concrete has larger stress in blast load due to the strain rate effect. but is it normal to reach compressive stress more than 100 times Fcu of the concrete?