I have a project where I am using #6 and #7 rebar for an 8" CMU wall. The design code is 2006 IBC and the required masonry rebar lap splice length is 72db due to the stress in the bars. So for a #6 and #7 bar, the required lap splice length is 54" and 63", respectively.
The masonry contractor...
Are there any code provision that require ductile failure modes for cast-in anchors in CMU in high seismic areas? For example with concrete, ACI appendix D clearly outlines the requirement that ductile failure modes must govern anchorage design in SDC C or higher structures or that you can...
I am designing an occupancy category IV structure that is in a seismic design category of D. The structure is steel bar joists on CMU bearing-shear walls. Where the joists bear on top of the CMU walls, to transfer the diaphragm load to the top of the wall, I am debating whether to use tube...
I'm designing a storm shelter where the gross wind uplift is on the order of 225 psf. We will be utilizing either precast hollowcore planks or double tees as the roof system with a 4" topping to resist in-plane diaphragm forces.
How is the topping slab anchored to the roof members for net...
Section 303.3 of the ICC500 states: "Underground portions of storm shelters shall be designed for buoyancy forces and hydrostatic loads assuming that the ground water level is at the surface of the ground at the entrance to the storm shelter, unless adequate drainage is available to justify...
How would one go about designing a reinforced concrete slab-to-top of cmu wall connection in the attached sketch? What provisions in the masonry code would you use in designing the 90 degree rebar dowel attachment for the forces shown? This connection is for a storm shelter. I only have...
I am calculating the wind load on individual members for an exterior steel frame (open building).
Using ASCE 7-05 section 6.5.15 "design wind loads on other structures," does the force coefficients include the windward and leeward wind against the face of an individual member?
I am trying to calculate the gust effect factor for a four-legged exterior steel portal frame that supports a large piece of mechanical equipment. The frame consists of steel moment frames in each orthogonal direction (directly welded flanges at HSS tubes) and has bolted shear connections at...
I have a two story building. The interior partition walls at the ground level and upper level are all metal stud walls with deflection tracks up to the joists/beams above each level.
When calculating the effective seismic weight at the upper level, I know the code mandates that you add 10...
I have an elevator shaft for a two story building made out of 8" concrete. I am not using the elevator walls for shear walls for my lateral system, however, they are carrying some floor load from the upper level.
I obviously need to design this for some seismic load, however, I don't know...
I am checking connection steel shop drawings for a job. I have an HSS steel column sitting on top of a girder cap plate connection (see attached sketch) with fairly high loads (260 kips from the column above, 100 kips from the girder). All the loads are gravity only with no moment transfer. I...
In my soils report, the geotechnical engineer has given me an ALLOWABLE coefficient of friction of 0.3. When using retaining wall software, I input this value. The software calculates all of the dead load of the wall, D, multiplies this value by the inputted coefficient of friction, and gives...
How does one treat the design of an embed. plate (with a group of headed studs) when it is in close proximity to another embed. plate? The type of embed. plate is cast into a concrete wall taking mainly vertical load from floor joists (therefore, there is no edge distance in the direction of...
If you are connecting to the flange of a WF shape with a shear tab or double angle connection, do you have to design the column for the moment M = P*e where "P" is the end reaction and "e" is half of the WF column depth? What about when you are connecting to the wall of an HSS tube with shear...
I have a 17" square baseplate sitting on a 7' square spread footing with 2" grout. When checking the bearing of the concrete, is the bearing area "A2" the area of the baseplate or is it (17" + 2*2")*(17" + 2*2") assuming the grout spreads out at a 45 degree angle on all sides? Or is it the...
I want to use rebar for anchor bolts, specifically, ASTM A615 Gr. 75. My reactions involve rather high moments and tension loads and I am therefore embedding the rebar into a drilled pier (and developing the bar). What failure modes do I need to consider? For tension, do I just need to make...
When calculating the shear friction demand for an interface with shear both parallel and perpendicular to the shear plane, do you just take the resultant of the two forces ( sqrt(Vperpendicular^2 + Vparallel^2) ) and use that value to calculate the required area of the steel?
I have a two story wf column in a corner of a building. In the strong axis direction, the column is pinned at the base and has moment connections going into it at both the upper floor and roof levels (it is part of a two story moment frame in that direction). therefore, my k value is 2 with an...
For an embed plate with headed studs, free edges on both sides and the top, with the vertical load away from the top edge, what does the failure plan look like for the shear parallel to edge? Will the failure plan start from the anchor nearest the edge (with half of the vertical load) and...
