Chapter 10, Problem 20RQ

Grade is being established to the bottom of a footing that is 24” thick. The elevation of thetop of the footing is 102.33’. the elevation of the existing grade is 106.14’. the backsight of thesurveying instrument on a benchmark of 100.00’ is 6.78’. what is the correct reading for the rodat the bottom of the footing?

6.48 This "double" nozzle discharges water (p = 62.4 lbm/ft³) into the atmosphere at a rate of 16 cfs. If the nozzle is lying in a horizontal plane, what X-component of force acting through the flange bolts is required to hold the nozzle in place? Note: Assume irrotational flow, and assume the water speed in each jet to be the same. Jet A is 4 in. in diameter, jet B is 4.5 in. in diameter, and the pipe is 1.4 ft in diameter. A 30°F B Problem 6.48 Xx

6-1 For the rectangular beam shown in Fig. P6-1, (a) Draw a shear-force diagram. (b) Assuming the beam is uncracked, show the direction of the principal tensile stresses at middepth at points A, B, and C. (c) Sketch, on a drawing of the beam, the inclined cracks that would develop at A, B, and C. 10 kips A B 1 kip/ft 7.5 ft Fig. P6-1 + 7.5 ft 6 ft 10 kips

6.85 A reducing pipe bend is held in place by a pedestal as shown. There are expansion joints at sections 1 and 2, so no force is transmitted through the pipe past these sections. The pressure at section 1 is 20 psig, and the rate of flow of water (p = 62.4 Ibm/ft³) is 2 cfs. Find the force and moment that must be applied at section 3 to hold the bend stationary. Assume the flow is irrotational, and neglect the influence of gravity. 6 in. diameter + 24 in. 24 in. (3 4 in. diameter Problem 6.85

6.79 A cart is moving along a railroad track at a constant velocity of 5 m/s as shown. Water (p = 1000 kg/m³) issues from a nozzle at 10 m/s and is deflected through 180° by a vane on the cart. The cross-sectional area of the nozzle is 0.002 m². Calculate the resistive force on the cart. 5 m/s D 10 m/s Nozzle Problem 6.79

Oil of specific gravity 0.800 acts on a vertical triangular area whose apex is in the oil surface. The triangle is 9 ft high and 12 ft wide. A vertical rectangular area 8 ft high is attached to the 12-ft base of the triangle and is acted upon by water. Find the magnitude and position of the resultant force on the entire area.

What types of constraints did Covid-19 cause in duration of activities on different construction projects?

Post-tensioned AASHTO Type III girders are to be used to support a deck with unsupported span equal to 90 feet. One level of Grade 270, 10 x 0.6" Ø 7-wire strand are used to tension the girders. The girder is simply supported at both ends. The anchors are located 2" from the neutral axis at the supports while the eccentricity is measured at 14" at the midspan. Use maximum values for ranges (table values). The tendons are encased in flexible metal sheathing. Assume and loadings are placed immediately after stressing. Determine the stresses at the top and bottom of the beam, including the stress at the level of steel after three years. Given the following parameters: F'c = 5000 psi Fy = 240 ksi (Bonded, Stress-relieved) Fu = 270 ksi = Es 29,000 ksi Ec = 4,030 psi Fj = 235 ksi A = 1x0.6" 07-W.S. = 0.217 in² Yc = 140 lbs/ft³ ΔΑ = 3/8" RH = 33% Superimposed Service Load = 10 kips/ft (excluding self-weight)

FIG. P5.66 40 kN B 4 m A 20 kN 10 kN/m C 8 m 8 m