Hydrated Lime in Cement Work.

Progress, Volume VI, Issue 4, 1 February 1911, Page 552

Hydrated Lime in Cement Work.

(Richard K. Meade in Municipal Engineering.) As an actual waterproofer, hydrated lime is not surpassed by any of the waxes and paraffine compounds at the present time used for this purpose. Many of these compounds are organic, and in time will volatilize, leaving the concrete porous. Hydrated lime, on the other hand, is inorganic or mineral, and will remain where it is put. As an example of the ‘waterproofing properties of hydrated lime, this was employed upon a large gas holder at Kingston, Ont., which had been practically a failure, owing to the leakage of the concrete Avail of the gas holder. Several waterproofing methods were tried, all of which failed, and it was not until this wall was chipped back from 3 to 6 inches by means of pneumatic chisels and a new wall composed of concrete, containing about 18 per cent, of the weight of the cement of hydrated lime had been added, that the tank was waterproof. The addition of hydrated lime to cement makes the latter more plastic and easily trowelled. It also improves the adhesive properties. A mixture of equal parts of hydrated lime and Portland cement makes an ideal mortar for laying brick. The addition of hydrated lime to concrete blocks makes the hitter whiter, tougher, and waterproof. Hydrated lime is not only the best but also the cheapest waterproofing compound known, since it replaces so much cement and the oily additional cost is the difference between the price of cement and hydrated lime, which is slight, even at the present low price of cement. In using hydrated lime first cover the bottom of the mortar box with water and add the hydrated lime and more wafer as is necessary. Some mechanics prefer to soak the hydrated lime at least twelve hours before using, claiming more plasticity in its manner of working. For Blaster Mortar First or Scratch —3501 b. hydrated lime, % yard screen sand, 2 bushels hair. Should cover' about 100 square yards. Second coat.—2oolbs ; hydrated lime, 1/5 yard screen sand. Should cover about 100 square yards. Putty or white coat.—Use about one-half as much plaster to gauge with as is commonly .used with putty made from lump lime. If wall is dry sprinkle or dampen with brush before putting on white coat,

,■ . '• I? as labour will be lessened. Float finish.— 3001bs. hydrated lime, Vi yard Screen sand. Should cover about 100 square yards. For stone mortar.—2oolbs. hydrated lime, % yard screen sand and add water. For brick mortar.—2solbs. hydrated lime, % yard screened sand. „ Hydrated lime and Portland cement mixture for laying brick and stone.—For hard mortar for these purposes use equal parts by weight of hydrated lime and Portland cement. Add required amount of sand to properly gauge up mortar. , For waterproofing concrete and concrete blocks.-—-Replace 15 to 20 per’cent, of the weight of the cement used in the mortar by hydrated lime.

floors will be surfaced with a special composition of varying colours in the different rooms. The baseboards are to be of the same material as the floor carried up as a border. The house will have two fireplaces, with window seats on either side, and a square of red tile in front of each. The fireplace and mantel will be of solid reinforced con-

other off the living-room. These are entirely separate from the entrance portico giving the full privacy of an interior room with the advantage of screened exposure on three sides. The porches open off the living and dining-rooms through two generously big French doors, making each porch a unit with the interior room. The bouse is typically modern. It has