Hello all! I have been looking for and answer to this question and cannot seem to find it anywhere. I am designing a rigging system and need to use (1) 1 1/2" diameter A490 bolt that will be fully in tension (hanger connection) My question is do I need to install double heavy hex nuts to to...
I appreciate all the input and I am going to check using relative stiffness.
The project is moving so fast and they are building the structure now and will be pouring concrete in the next few days so I just want to make sure that I have all my bases covered thats all. I guess I just went into...
I just want to make sure that the detail that I provide for this connection between the transfer beam and the column will no produce a rigid connection and induce a moment into the column.
jike,
That would assume that the beam to column has a fixed support. The beam was designed as simply supported so the moment at the columns is zero unless the connection that is detailed has rigidity. From what I understand from the code is that the equations checking the axial capacity of a...
The foundation is in place and they are forming the columns now. Basically my transfer beam sits over top of the column were I have the beam reinforcing bars running over the top of the column and being hooked at the end. The column reinforcing bars run through the transfer beam to develop the...
I am designing a 9 story concrete structure that employs a two way slab system supported by 16" sq. columns. At the second floor level a column is being supported by a reinforced concrete transfer beam that is 16"X42". I designed the beam as simply supported and the columns supporting the beam...
The spreader beam will be able to support itself. The beam will be in compression due to the axial load induced be the rigging cables and will have a straight pull on the bottom with beam clamps. I am concerned about the stability of the member being picked. It is 128 feet long. If the spreader...
Is there a criteria or a rule of thumb on how long a spreader beam needs to be for a crane lift? I have always made the spreader beam at least 1/3 of the span of the beam being lifted as my length. I have a situation were I cannot do that and I was wondering if there is any criteria for...
When we designed the sheeting system we neglected hydrostatic pressure because the water would seep through the gaps in the lagging and that the site was to be dewatered. In any case the TA is forcing us to add a detail to our drawing showing a one bag cement to sand mixture behind the lagging...
BorntoDrill,
Thanks for the response. I understand your concern with the drypacking and I agree. As far as the site I am working on now it will have a dewatering system. The transit authority that we are working for insists that the lagging needs to be drypacked so that no soil failure will...
Is it a common practice to show a louver and backpacking behind timber lagging in a soldier pile retention system? We specify to replace any lost soil behind the lagging before installation of the next board to have solid soil behind the lagging. I was told however that it should be backpacked...
How is the point load applied? I wouldnt recommend a double channel spreader beam as you described. If a double channel was to be used they should be put back to back to put the load into the major axis of the channels. Channels placed toe to toe are eccentric and unconventional. Also depending...
I figured out the maximum spacing of my baces to be able to get the full allowable stress (Lb < Lc) using L/rt. The spacing of my braces can be at a maximum of 14 ft to get the full allowable stress of 0.60FY. Now I need to find out what force do I need to design these discrete braces for? 2% of...
