For the design of a residential cellar extension using new CIP retaining walls down to 10ft below grade, the allowable bearing is tentatively assumed to be 1500 psf. There is no geotech report available. The cellar will be an extension of an existing rowhouse cellar. At a minimum, a test pit...
Am trying to determine a code compliant method to determine if a new, higher live load can be accomodated by an existing CIP plate. Plate: 8", 4ksi with only bottom bars (#4's @13" ea way) explicitly stated. Top bars indicated only with codes that refer to a lost drawing. Overall the building...
Hi All,
I need to buy a packaged freezer unit and have received a spec from Norlake with the following electrical data:
208-230V/60Hz/1P
Total system refrigeration amps = 11.4A
Total system defrost amps = 7.1A
Min. circuit amps = 14.2A
Max fuse size = 20A
We told Norlake that we have a 15A...
There's an existing, unreinforced masonry building, 4 stories, that was built ca. 1900. The perimeter masonry walls are load bearing, the interior is framed in steel with heavy cinder fill on terra cotta arched floors (155 lb/sf DL).
One of the exterior walls (5 wythe at 1st floor, 3 wythe at...
We have a 12" slab on grade and some small amount of foundation work (say, 18 yd3), which had a low f'c (around 2800 psi). Corrected core tests from over 56 days came in at around 3550, which is more than the spec'd f'c = 3500.
Petrographic tests/micrographs show the culprits to be very high...
I'm working on an HSS architecturally exposed structural steel canopy with some stainless, exposed screws, currently designed as countersunk (3/4" dia - 10). The aisc 360-05 spec does not list anything for stainless steel bolts or screws.
A193, B8(M) could work based on calcs, but if they...
The old New York City Building Code(1968) allows for use of 30 psf wind loads for up to around 100ft for buildings. This is for the MWFRS as well as cladding to my knowledge. I've seen it used for both.
ASCE 7-02 and other versions of course require much higher wind loads for cladding...
I'm trying to determine how much yielding around a 2" diameter hole in the side of a 7" diameter pipe column is acceptable. The column is subject to bending and axial load.
We've modeled the hole with FEM solid modeling and pretty well defined the areas of yielding - a shallow zone around...
Hi All,
In Table 6-9 ‘Allowable Stresses for Casting Alloys’ (Aluminum) in AASHTO's Standard Spec for Structural Supports for Hwy Signs, Luminaires..., Section 6, the allowable stresses for A444 and A356 are given for various tempers. The allowable tensile/compressive stress for bending for...
A streetlight base made of aluminum (357-T6) is to be bolted to a reinforced concrete foundation. The 4 foundation bolts are hot dipped galvanized steel.
The outside of the light base is subject to urine, deicing salts and sea air.
I first considered some kind of plastic plate (ABS for...
I'm working on a parapet that's 48" high. It's 3 wythes thick with the inner two wythes acting compositely. The outer wythe is a veneer separated by a cavity.
ACI 530-02 and UBC say a 2" min collar joint for 5' height for the 2 grouted wythes. I don't think we can go much less than that...
I’m trying to determine the bearing stresses for a sleeve connection. Marks’ Handbook has a number of bear stress formulas, but not for the case where you have a pipe within a pipe with a clearance fit so there’s some kind of small gap between the inner pipe section and the outer. Please see...
To verify some calc's for an existing composite parapet wall, we need to take some samples of cmu block from the wall and have prism tests done. There's roughly 150 ft of the known parapet wall type - and about 400 ft of an unknown parapet wall type. Any suggestions on min. number of sampling...
I’m working on a streetlight with some cast aluminum parts. The base connecting the pole to the foundation is cast and I’ve spec’d 771.0-T71 up to this point as it has the required fu=48 and fy=45 psi required by the calc’s. But 771.0-T71 is only listed for sand casting so far as I’ve...
Does anyone have advice on sealing off voids of an aluminum extrusion (6061 T6)? So far I've specified welding them shut. The extrsuion is elliptical in section with a number of elliptical voids, and forms part of a proposed light arm. (Please see attachment.) The goal is to keep water or ice...
Does anyone know where I can find an excerpt of the current Canadian Nat. Building Code covering load combinations for limit state design as well as service load cases?
Thanks,
We have a possible project with a 4 lane roadway over an underground parking structure with 2 levels. Do you apply AASHTO code to the roadway and ACI-318 code to the parking structure? Or ACI-318 to the entire structure including the roadway?
One issue for example is for transference of loads...
Hi,
We have a site where the owner is considering a 5 level deep cellar (about 65' deep total) with the lower half of he excavation in clay. Some areas of the cellar would have the retaining walls going down full depth without any cellar slabs for lateral stability. All of the proposed...
Anyone have any suggestions for a good structural properties refenence book? Need one with for structural engineering firm for typical materials such as steel, aluminum (all the different alloys commonly used); and less typical such as titanium, polymers, glass, ceramics.
I've seen 'Concise...
Does anyone know if it's feasible to construct a CMU infill wall within a braced steel frame? The CMU is for sound damping, not structure. Obviously, for a chevron braced frame the cmu would be above and below the diagonals.
This is a moderate seismic zone.
Thanks for any thoughts.
