I mentor a lot of young engineers in my job. Don't be afraid to ask your boss questions and learn from him/her the specifics of what you are to do. Develope that line of communication. It is important. Don't expect them to give you the final answer and do the work for you but do ask questions.
If you have a ridge board (non-structual i.e.2x12) then your rafters also have a large axial load and you have to worry about spreading your walls or use collar ties as Mike suggested to take out spreading loads. Collar ties if not at the wall level acan add in big moments which complicate your...
It sounds like the home is a mix of several styles of log building. The Log Home Builders Association of North America (LHBA) teaches using 1/2" rebar for connecting the logs. I have engineered homes for them for almost 20 years along with other companies and log building methods. I use the...
Two places I have used these devices.
1. Tall narrow heavily loaded shear walls in multiple story buildings (high wind or seismic lateral loads).
2. Log homes where you are trying to use friction between the logs as the first failure mechanism for lateral loading and bearing on the rods as the...
Earthbound Inc, Monroe, WA also has a system. I have used their Earthbound Impasse Device but now they seem to be using a new device called their slackjack with is similar but can allow for more shrinkage and higher loads.
http://www.holdown.com/
Lateral loads from the upper floors must be taken all the way to ground so yes they need to design the framed daylight basement wall for shear.
ASCE 7-05 12.14.1.1 (5) states "the structure shall not exceed 3 stories in height". There are many other restrictions that would need to comply...
I agree that with the 4" wide chinking strips you will get some bending in the all thread. I have used the pipe concept before in log trusses when I needed more bearing area or had bending that couldn't be handled otherwise. With the squash blocks 8 ft apart you don't get a lot of shear...
The 5400 lb/person is the factored load. I don't know many 5400 lb people around. When you do your PL/4 for the moment you length can be the horizontal projection instead of the full length so you get the load and perpendicular distance. That saves you a little since the horizontal projection...
As far as I know the no current codes allow you to use lapped siding for shear wall strength. My house was built in 1975 here near Seattle, WA. It is a two story with only lapped siding. No diagonal bracing or anything else that I can find. Jut lapped siding, tarpaper, 2x4 studs and gypbd. It...
Bylar,
The Canadian log building standards published by the International Log Builders Association recommend allowing for up to 1/2" per foot settlement when building with green logs. That would be 4" of settlement in an 8' wall. I have had some builders who recommend designing for up to 3/4"...
I haven't used the pipe method but unless you have the pipes tight in the hole full height of the wall, the pipes will not bear unless there is some movement in the logs. This means you are relying on the friction between the logs most of the time and the pipes are only there to resist ultimate...
The maximum spacing of the thru bolts is dependant upon your shear stress. The actual spacing is more often based on where your openings are as long as you don't exceed the maximum.
If you are using lag bolts or spikes or pounded in rebar you usually will not include thru bolts. You will just...
Thru bolts are placed at spaced lengths usually about 4 ft o.c. Where there are openings which block that equal spacing you place the bolts on both sides of the opening. There is usually a thru bolt in the overhang at the corners just because it is an easy place to be able to adjust it.
Some...
Uplife is one of the reasons I haven't liked the drift pin method because the logs are not mechanically tied together. If you use full height rods attached to the foundation or bottom log, lag screws, pounded in rebar or spikes there is some mechanical resistance to uplift because the...
Most log walls are relatively low and long and have a lot of weight. They don't have as much problem with overturning as they do in racking shear. That is why you tend to look at a load per length along the walls and then size some type of connection (thru bolt, spike, pipe, dowel pin) that...
Here is a link to APAs paper on design of engineered wood portal frames which would be your wood moment frame.
http://www.apawood.org/pdfs/managed/TT-074A__Portal_Frame_for_Engineered.pdf
Here is another link to an APA article on design of narrow walls which references more good papers...
This may not totally be the answer to this question but APA published a report of tests using double 2x instead of single 3x lumber for these high shear load wall diaphragms. It is TT-076 Shear Wall Lumber
Framing at
http://www.apawood.org/level_c.cfm?content=pub_tch_libmain
APA recommends...
If you are going to have an interior load bearing wall supporting the 2nd floor make sure that all the members and interior foundations are adequate to transfer these loads to the ground. When adding a second story the load path is very important. Follow all your loads through to ground. This...
