Appendix D of ACI 318-08 provides formulas for calculating the projected concrete failure area, ANC on page 421 for varying number of rods. These formulas are to calculate the ANC when ALL of the rods are in tension, i.e. when ALL the rods are experiencing uplift when in the process of being...
I have got a question about the placement of minimum temperature and shrinkage steel, say for a 35" thick rectangular footing 14 feet long and 5 feet wide. Let's say, that all I need for my footing is minimum temperature and shrinkage steel.
Hence, Ast = 0.0018bh = 0.0018 * (14*12) in * 35 in =...
I have got a question about the design of a group of four anchor bolts that are tied with hair pin ties. My hair pin ties are #7 bars and about 6'-6" long. They are in the shape of V with a "flattened bottom". The "flattened bottom" is pointed towards the outside of the slab and hooked around...
I have an exterior concrete spread footing, say 10' x 10'. The thickness is 3', say. My column is 2' from the edge of the footing. Therefore, my actual eccentricity, e is 10'/2 - 2' = 3. Now, I have been told that my eccentricity - the calculated eccentricity, that is - can be less than the...
I have got a general question about the design of a combined footing vs. a single footing. I have just finished a design of a single footing for a storage silo. It is founded on grade, with a soil bearing capacity of 3 ksf. My footing will be a 19 ft by 19 ft by 3 ft thick footing, reinforced...
Avc, as defined in ACI 318 Section D.6.2, is the projected area of the failure surface on the side of the concrete member at its edge for a single anchor or a group of anchors. Now, my aim is to calculate the concrete breakout strength of anchor in shear. ca1 is the distance from the concrete...
I am checking the concrete strength of my footing, and came across this formula for the nominal moment of a one-foot section of my footing:
Mn = 5 * (fc')^1/2 * S
S = section modulus
Could someone please verify the validity of this formula, and where is this formula stated, i.e. provide some...
I have got a question about concrete development length, and whether I can reduce the development length if the tension in my steel is less than the maximum tension that my steel reinforcement can take. Reference is ACI 318-05
Section 15.6.2 - "Calculated tension or compression in reinforcement...
In ACI 318-05 and also 318-08, Section 12.2.2 commentary, it is stated that "In the development of ACI 318-95, a comparison with past provisions and a check of a database of experimental results maintained by ACI Committee 408 indicated that for No. 6 deformed bars and smaller as well as for...
I posted this in the General Engineering program section but have had no luck there. Hope I can get some responses here.
In the Masonry Wall design portion of Enercalc v5.8, what does "parapet height" refer to? The definition provided in Enercalc Help is, "This portion of the wall extends...
In the Masonry Wall design portion of Enercalc v5.8, what does the parapet height refer to? The definition provided in Enercalc Help is, "This portion of the wall extends above the Clear Span Height and will apply a concentrated moment due to wind or seismic loads to the top of the wall...
In the stability anlayis of a cantilevered retaining wall for a short roadway, with dirt on both the heel and the toe, can we use the soil above the toe in helping to provide sliding resistance?
The roadway is on the side where the toe is, and the dirt is almost up to the top of the wall on the...
I would like to get feedback on ASCE's requirement for rain-on-snow surcharge loads on tanks, say tall silo tanks. Is this required? Section 7.10 of ASCE 7-05 states that, "for locations where pg is 20 PSF or less, but not zero, all roofs with slopes (in deg) less than W/50 with W in feet shall...
