Browse Forums Renovation + Home Improvement Re: PFC Beam Question 8Feb 21, 2014 2:14 pm hi beechworth, I am an engineer and its not just the moment of inertia (MI) that matters. What actually matters is the Z (section modulus), which is MI/y. 2x 150 PFC would give you almost the same Z as that of 1 x 230PFC 230PFC, Z = 232.7E3 mm3 150PFC, Z = 111.2E3 mm3 I am not sure what factors of safety (FOS) was assumed when your engineer did the calculations. But my gut feel tells me that with the usual FOS values 2x150PFC should do the job. My Building Thread: viewtopic.php?f=31&t=62776 Re: PFC Beam Question 9Feb 21, 2014 3:39 pm wrexter what are your size constraints? Mainly around the 2 house stumps the beams will need to rest on and which currently support the wooden beam. It is a wooden stump at one end and concrete at the other. Both of which I need to cut in order to allow the PFC/UB/UC to sit on. The width of UC is such that over half the beam will be in mid air Re: PFC Beam Question 10Feb 21, 2014 3:40 pm navarch hi beechworth, I am an engineer and its not just the moment of inertia (MI) that matters. What actually matters is the Z (section modulus), which is MI/y. 2x 150 PFC would give you almost the same Z as that of 1 x 230PFC 230PFC, Z = 232.7E3 mm3 150PFC, Z = 111.2E3 mm3 I am not sure what factors of safety (FOS) was assumed when your engineer did the calculations. But my gut feel tells me that with the usual FOS values 2x150PFC should do the job. Thanks for that. Will do some further calculations - what would the Z of a 180PFC be? Re: PFC Beam Question 11Feb 21, 2014 4:22 pm 180 PFC ; Z=157e3 mm3. Two of these connected appropriately should give you more Z than a single 230PFC and should be fine for your job. My Building Thread: viewtopic.php?f=31&t=62776 Hello everyone, After some suggestions and ideas about how to put a concrete path around the drop edge beam area on our new build. We are required to have a concrete path… 0 13024 The distance between my DEBs varies from 4.1m at the narrowest to 8.1m at the widest. 5 27448 |