Placing booms
Placing booms support a 5-in.-diameter pipeline which re-ceives the discharge from a concrete pump and places it inthe forms. Booms have three or four articulating sections.The booms are mounted on a turret that rotates to enable the
discharge of the pipeline to be located anywhere within a cir-cle. One type of boom telescopes 17 ft. Most booms are per-manently mounted to the trucks on which they are transported, along with the concrete pump. Some booms are designed to be removed from the truck and mounted on a pedestal that can be located in the placement area or support- ed on the floors of buildings under construction. There also are placing booms designed to be used only on a pedestal or to be mounted on tower cranes. Placing booms should never be used as a crane and must be inspected for structural integ- rity on a regular basis.
Specialized equipment
Concrete pumps and placing booms have been developed that are mounted on ready-mixed concrete trucks. These units are capable of placing the concrete mixed and trans-
ported in the truck that carries them and can also receive con- crete from other ready-mixed concrete trucks to complete a placement. These units usually have the capacities of small general purpose pumps (Section 2.3.2).
2.7—Safety
Concrete pumps are powerful machines that utilize high hydraulic oil pressures, concrete under high pressure, and compressed air for cleanup. Safe operating practices are a necessity for the protection of the pump operator, ready- mixed concrete drivers, and the workers placing and finish- ing the pumped concrete. The American Concrete Pumping Association has prepared a detailed Safety Manual7 for those who supervise or engage in concrete pumping.
Pipe inside diameter | In. | 2 | 3 | 4 | 5 | 6 | 7 | |
Cross-sectional area
(inside pipe) |
2
in. |
3.14 | 7.07 | 12.57 | 19.63 | 28.27 | 38.48 | |
ft2 | 0.02 | 0.05 | 0.09 | 0.14 | 0.20 | 0.27 | ||
Volume of concrete
per 100 ft of pipe |
ft3 | 2.18 | 4.91 | 8.73 | 13.64 | 19.63 | 26.73 | |
yd3 | 0.08 | 0.18 | 0.32 | 0.51 | 0.73 | 0.99 | ||
Weight of concrete
per 10-ft section of pipe |
Lb | 32.72 | 73.63 | 130.90 | 204.53 | 294.52 | 400.88 | |
3
Pipe length per yd of concrete |
Ft | 1237.59 | 550.04 | 309.40 | 198.01 | 137.51 | 101.03 | |
Inside
diameter In. 2 3 4 4 5 5 5 5 6 6 7 |
Wall | Weight, lb per ft | ||||||
Line
empty |
Concrete
only |
1-ft
section |
10-ft
section |
|||||
Gage | In. | |||||||
11 | 0.120 | 2.72 | 3.27 | 5.99 | 59.89 | |||
11 | 0.120 | 4.00 | 7.36 | 11.36 | 113.62 | |||
11 | 0.120 | 5.28 | 13.09 | 18.37 | 183.70 | |||
9 | 0.150 | 6.65 | 13.09 | 19.74 | 197.38 | |||
11 | 0.120 | 6.56 | 20.45 | 27.01 | 270.15 | |||
9 | 0.150 | 8.25 | 20.45 | 28.70 | 287.03 | |||
7 | 0.188 | 10.42 | 20.45 | 30.87 | 308.70 | |||
— | 0.250 | 14.02 | 20.45 | 34.47 | 344.71 | |||
11 | 0.120 | 7.84 | 29.45 | 37.30 | 372.96 | |||
9 | 0.150 | 9.85 | 29.45 | 39.30 | 393.05 | |||
11 | 0.120 | 9.12 | 40.09 | 49.21 | 492.13 |