Celt83
Structural
- Sep 4, 2007
- 2,070
Cue "Oh great this topic again"
I've read a ton of the existing threads on what amounts to this subject but everything seems to die right before it gets to the spot I am concerned with.
I believe there should be a check, akin to Appendix D/Chapter 17 or Strut-Tie Nodal Stresses, beyond Ld/Ldh of rebar into a foundation but I haven't found a resource that goes beyond those checks.
Attached picture to set up a situation:
Left configuration:
Steel column in pure tension anchored to concrete pier with anchor embedment such that pier vertical reinf. is developed on either side of the failure cone precluding the concrete tension failure modes for the anchors and thus developing the tension into the bars. Square foundation proportioned such that the pier vertical reinf. can be cast in at a depth equal to Ldh+cover and such that the self weight of the pier+foundation exactly counter the applied tension. ACI and convention in reference texts at my disposal would seem to say that the provided Ldh embedment of the rebar is all that needs to be checked.
Right configuration:
Steel column in pure tension directly anchored to the foundation. Anchor spacing and embedment match that of the left configuration. Sqaure foundation is proportioned such that it's self weight exactly counteracts the applied tension and that anchorage depth can be achieved + appropriate cover. ACI and convention in reference texts point to Appendix D/Chapter 17 checks for this situation which may result in a lower capacity than that implied by the left configuration.
Are there any reference available that go into if/when an additional Appendix D/Chapter 17 style check needs to be performed for developed reinforcement, best approach I can think of to use for now is look at it like a node in a strut and tie model and see if the associated strut/plain concrete tie stresses work out.
Open Source Structural Applications:
I've read a ton of the existing threads on what amounts to this subject but everything seems to die right before it gets to the spot I am concerned with.
I believe there should be a check, akin to Appendix D/Chapter 17 or Strut-Tie Nodal Stresses, beyond Ld/Ldh of rebar into a foundation but I haven't found a resource that goes beyond those checks.
Attached picture to set up a situation:
Left configuration:
Steel column in pure tension anchored to concrete pier with anchor embedment such that pier vertical reinf. is developed on either side of the failure cone precluding the concrete tension failure modes for the anchors and thus developing the tension into the bars. Square foundation proportioned such that the pier vertical reinf. can be cast in at a depth equal to Ldh+cover and such that the self weight of the pier+foundation exactly counter the applied tension. ACI and convention in reference texts at my disposal would seem to say that the provided Ldh embedment of the rebar is all that needs to be checked.
Right configuration:
Steel column in pure tension directly anchored to the foundation. Anchor spacing and embedment match that of the left configuration. Sqaure foundation is proportioned such that it's self weight exactly counteracts the applied tension and that anchorage depth can be achieved + appropriate cover. ACI and convention in reference texts point to Appendix D/Chapter 17 checks for this situation which may result in a lower capacity than that implied by the left configuration.
Are there any reference available that go into if/when an additional Appendix D/Chapter 17 style check needs to be performed for developed reinforcement, best approach I can think of to use for now is look at it like a node in a strut and tie model and see if the associated strut/plain concrete tie stresses work out.
Open Source Structural Applications:
