A colleague approached me with a structural problem. He issued a drawing for construction where the tension reinforcement for a beam were specified less than required. (As(Reqd)=1783 mm², As(Prov)=1000 mm²). The slab and beam are now cast but formwork is not removed. I have advised him not to...
I am working on a project for replacement of small (5HP) compressors. Vendor shop drawings show light gravity and lateral reactions. (4.5 kN gravity and 2.0 kN lateral max) Existing slab on grade is a, 8" thick concrete with two layers of rebars. I have no concern if the slab will be able to...
I have just been to review the floor framing of a site. Though wall framing was not part of my scope but I noticed gaps of 3/8" to 3/4" at the horizontal connection of plywood sheathing. I know that recommended gap for expansion of sheathing is 1/8" to 1/4" minimum but what I found on site was...
I posted a query two years ago regarding concrete foundation walls which are not considered laterally supported if the top end is not reaching the floor diaphragm. ( https://www.eng-tips.com/viewthread.cfm?qid=451821 ) I have just thought about a solution where by the wall studs are extended up...
My client bought two bays in a commercial building and wants to connect them by creating an opening in the demising CMU wall. The wall is non-loadbearing but it is ±24 feet high. He wants an opening of 8'-0"H x 10-'0"W opening. I am thinking of adding two channels on each side of the wall...
I have worked previously in locations where British and Indian codes were in use. Both these codes consider the amount of flexural steel reinforcements (Tension as well as compression) in flexural members to determine shear capacity. Now I am working in Canada and CSA A23-04 does not utilize the...
I provided a normal HSS102x102x6.4 lightly loaded column (axial 50kN, shear 2kN) with a 20 thk base plate and 4-20Ø A325 anchor bolts with Hilti HIT HY200 on a project where the base building is existing. Now the architect has come back to tell me that he cannot accept the base plate and...
I have come across a project where I have to design a wall for a maximum lateral force of 1.25 kPa which is going to last a second and two. (Due to fire suppression system) Does anyone has any idea if I have to design it like any other case of sustained lateral pressure or I can reduce this...
I am quite clear on all the load combinations at ULS as prescribed by National Building Code of Canada. But cannot find any information on what combinations to use at SLS. If it is sum of all Dead + Live + Snow + Wind loads multiplied by one, then it is more than many ULS combinations. Is this...
thread507-51453
I have to design a splice for a C6 purlin which was cut to accommodate the installation of a new equipment and now has to be replaced. The cut was at 0.2L distance from both supports. I am getting moment of 4.7 kN.m and shear of 4.7 kN. The splice shall be a 3/8" thk x 4" plate...
Can the concrete foundation wall in the image be considered as a laterally supported at top? If not, then what are my options to design it as anything but a cantilever retaining wall?
I am designing a reversed-L shaped retaining wall. (Cannot have a heel due to boundary restriction and retained earth being higher on neighbor side) If the wall height is less than 1.0m and providing 0.9 ~ 1.0m long 50mm thick rigid insulation, would it be OK to provide base around 200mm below...
Does anyone have any information about how the values of Maximum Unsupported Beam Length (Lu) is derived in the Beam Selection Table of CISC Blue Book (Handbook of Steel Construction)? I have seen some threads on Eng-Tips.com which has some formulas to calculate Lu based on AISC Imperial values...
