Bond Friction

[jramosjr]

I'm currently designing an API 650 tank to Appendix E. This tank will be set on top of and existing conrete base. The client is proposing the use of HAS rods with an epoxy adhesive (no welded nut nor hooked). However, section E.7.1.2 states that anchorage systems based solely on bond fricton shall not be used when seismic design is required. It also says that "post-installed" anchors may be used provided that testing validates their ability to develop yield load.

Is it OK to use these HAS rods with an epoxy adhesive? What exactly does the code mean by "post-installed" anchors? What kind of testing needs to be done?

Jorge L. Ramos, Jr., MSCE, PE
Alonso & Carus Iron Works, Inc. (

http://www.alonsocarus.com)

Euro-American Steel Co., Inc. (

http://www.euroamericansteel.com)

 

[JStephen]

In the old AWWA D100, they gave a formula for bond strength on a plain rod for use with hooked anchor bolts. This was for cast-in-place bolts. I think this is the approach they wish to avoid.

Read Appendix D in the latest ACI-318 for more detailed bolt requirements.

 

[IFRs]

Does 650 Appendix E indicate that anchors are required, IE the tank experiences uplift and is not self anchoring? Or is the tank stable and you are looking at horizontal shear or displacement?

 

[jramosjr]

Per Appendix E, the tank must be anchored.

Jorge L. Ramos, Jr., MSCE, PE
Alonso & Carus Iron Works, Inc. (

http://www.alonsocarus.com)

Euro-American Steel Co., Inc. (

http://www.euroamericansteel.com)

 

[IFRs]

I believe it says: "Post-installed anchors may be used provided that testing validates their ability to develop yield load in the anchor under cyclic loads in cracked concrete and meet the requirements of ACI 355." In this context I take "post installed" to mean a situation like yours where the slab is already poured without anchors. For the testing, what does ACI 355 say?