Does anyone have any load tables on CECO trusses? CECO makes concrete forms and Pre-engineered buildings. CECO = Concrete Engineered Company. It used to make trusses with cold formed top and bottom chords in the 1960 and 70's. That portion of the company is out of business.
I have a situation where we need to dig a 15' Deep trench for a 10' dia. x 60' long water tank. The trench only needs to be open for about 1 day. OSHA requires us to shore the trench or layer it back. Is there an easy and cost effective solution shoring the trench. The solution can bend, but...
How do you calculate the critical Storm? I use Hydrocad and I like it's simplicity. I would like to know how other calculate their critical storms. In the Critical Storm Detention method you determin the %increase for 1-yr volume(V1) between Post and Predevelopment(post V1/Pre V1-1.0)*100...
There is some confusion at our office of whether Horiz. Mas. Jt. Reinf. should be put in the masonry foundation wall below grade. According to NCMA Tech. Support, horizontal mas. joint reinforcing is Not required by code. I would like to get a consensus of whether other engineers require it...
I have been called by the owner to eliminate some intermediate x-bracing that is interferring with machinery operations. The building has 12 bays @ 25'in the direction of the runway beams. The runway beams are x-braced longitudinally in the 1st, 8th, and 12th bays for (2)10 ton cranes on the...
We have a project to install a pit inside an existing building. The soil is loose sand and gravel. The clear height inside building is 18'. It's possible the soil may be very wet. Due to the limited clear height, it would be difficult to drive sheet piles or I-bms. Any recommendations.
What structural loads are others using on there firewalls? How are others designing their firewalls? The firewalls must maintain structural stability when the building on the other side of the wall collapes. There seems to be 3 methods: 1)Free standing wall cantilevered from the floor(neither...
I have a 2x6 stud, 10.5' high. When I run the numbers, it can take 5.56k when braced in the weak direction and 0.49k when NOT braced in the weak direction. Can drywall provide the necessary lateral support? If Not, how do they build 2 story houses with walls made of 1/2"dry wall, 2x4 studs...
I have 2 concrete suppliers. One has No problem using #4 stone and the other is Not comfortable using #4 stone in exterior slabs. Does anyone know if there is any problem with using #4 stone in exterior slabs.
Can you use #4 stone in exterior conc. slab on grade. I have one supplier who says it is No problem and another who says you cannot use #4 stone outside. He says #4 has more deterious material, because it is not crushed as much.
He says ACI does Not reccommend it outside, but could not quote...
I'm posting concrete mixes on this page because we do Not have a Concrete page. Please review the following mixes and comment.
No. PSI Cement Sand #4 #57 #8 water air W.R.
(-) psi lb/cy lb/cy lb/cy lb/cy lb/cy gal oz/cwt oz/cwt
1 3000 470 1235 575 1085 300 35...
How do most people specify concrete floor slab-on-grade. Give ACI a little time and they will reverse their decisions. Concrete has too many variables. If you spec a highier strength mix, you get more cracking because of curling. Some want vapor barriers between concrete and granular...
If you have the Req'd flow Q, diam. D, Length L, manning's "n", and entrance loss Ke, for each pipe length, than you can calc. the head losses thru the pipe. he=Ke*V^2/2g; hf=29*n^2*L/[(D/4)^1.333]; hv=V^2/2g where he, hf, hv are the entrance, friction, and veloc. heads. The req'd head to push...
The Floodway is the portion of the floodplain that is reserved for the passage of the 100 yr. storm without raising the flood elevation by more than 1.0 feet. You cannot fill in the floodway, but you may fill-in the remainder of the flood plain(flood fringe). It appears that the location is...
We want to extend a buiding addition into a "Zone A" 100 yr floodplain. I'm hearing conflicting information from FEMA and others, and would like to get it clarified. Zone A is determined by approximate methods and does Not have a Base Flood Elev(BFE) or a defined Floodway. We know we have to...
We work in a local community that just came out with a new fee schedule, based on sf, for site plan review. For a 100,000 sf factory/warehouse they were going to charge us $70,000 to review the plans. This is probably 3x the cost for us to design the site, arch, structural, electrical...
Questions on roof diaphrams. Text books and field observations appear to differ. Assume a typ. building with parapet masonry walls, metal decking, and bar joist.
1. Walls with Bar joist perpend. to wall:
a. Chords: consist of bond beams, contin. angles, or portions of metal deck...
What methods are other engineers using for stormwater POST contruction water quality for 1 to 5 Ac sites. It seems that Extended Detention is the simpliest to adapt to our existing methods of detention. It requires 1" dia. orifices(metering water for 48 hrs.)which need to be protected by...
I would like to create a small engineering Peer Review group where we can meet monthly to review projects and other information. It would consist of approximately 6 engineers, meeting the 1st Thursday of the month, in the evening, at a local university, in a non-competitive atmoshere. The...
