Masonry Magazine May 1967 Page. 34
# Filtration and Chemical Treatment
Filtration is therefore recommended. Filtration is not purification; however, and a chemical treatment is required for all systems.
# Pool Water Methods
Where "fill-and-draw" is used, the pool is emptied and refilled at intervals depending on the usage and entrance of debris. Water is disinfected upon filling and thereafter as required. Where "flow-through" is employed, a continuous stream of water enters the pool. The outlet is adjusted to discharge an equal amount. A chemical disinfectant usually is injected with the entering water. With both methods, waste water is frequently used for such purposes as watering lawns. The main pool drain may discharge directly into a sewer if permitted by local authorities, but should be at an elevation sufficient to prevent sewer back-up from contaminating the pool. The supply line must feed through a broken connection at least 6 inches above maximum pool water level. This eliminates the possibility of pool water entering the public or domestic water supply.
# Piping Diagrams
Piping diagrams for filtered pools are furnished by the equipment manufacturer. The system generally includes a built-in surface skimmer which removes floating debris along with 50 percent of the recirculating flow; a floor drain for the other 50 percent of the flow and settled solids; a vacuum cleaner connection which is best built-in during construction even if the cleaner is not purchased at that time; a pump; the filter system; the disinfectant system; the pool inlet fitting; and the attendant piping and power wiring. All piping should be copper or plastic, adequately sized for negligible pressure drop.
# Plumbing Layout
In making the plumbing layout, consideration should be given for the future installation of a pool-water heater. Heaters require regular maintenance because of scaling by treated water. They demand almost daily flow adjustments. Because they may significantly extend the swimming season, heaters are furnished on almost one-third of new pool installations.
# Water pH
In addition to being disinfected, the water must be maintained at the proper pH (acidity-alkilinity) level. An acidic imbalance irritates eyes and skin and corrodes galvanized and cement finishes, while a basic unbalance causes calcium deposits and deterioriates chrome.
# Winter Requirements
Pools should be left filled year-round in most areas, and in fact, pools with nylon or vinyl liners cannot be drained because of the difficulty of realigning the fittings upon refilling. Leaving the pool filled prevents freezing of the sub-grade and possible frost heave. Moisture content of the concrete floor and walls remains essentially constant, eliminating a major source of cracking. Pipes must be drained and other equipment protected.
FIG. 4. TYPICAL BOND BEAM UNITS.
Note: Slots may be cast into the unit when molded or cut out with a masonry saw after unit has been cured.
7%"
7%" or 11%"
15%"
Sawed slots
a) Slotted unit
a) Slotted unit
a) Slotted unit
b) Unit with
b) Unit with
sections
sections removed
removed
for corner
b) Unit with
sections
removed
Detail a Standard wall unit modified Detail b Standard wall unit modified Detail c Standard wall unit modified
for use as bond beam unit.
for use as bond beam unit.
for use as bond beam unit.
FIG. 5. TYPICAL CORNER CONSTRUCTION FOR 12" WALL.
12 x 8 x 16" single corner units
12 x 8 x 12" units
Alternate courses
Standard 12 x 8 x 16" units
Minimum overlap
of reinforcing
steel = 32
bar diameters
FIG. 6. TYPICAL COPING DETAILS.
Cement plaster or concrete capping
Expansion joint
Brick coping and walk
1"-
Glazed face block
Slope walk away
from pool. Minimum 6" per ft.
½ cement plaster
Flagstone