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This historic book may have numerous typos and missing text. Purchasers can download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1919 edition. Excerpt:...the surfaces of the concrete thoroughly wet and broomed with a thin wash of neat cement grout. On completion of exposed surfaces of concrete structures, all defective areas should be pointed and filled; then uniformly coated with neat cement grout applied with a brush. Note: Where fireproofing is required for roofs an acceptable reinforced material other than concrete may be used, either pre-cast or of monolithic construction. The material should be capable of sustaining a live load of 40 lbs. per sq. ft.; should have a factor of safety of at least four; and the strength should not be materially affected by moisture. Forms. Where earth banks are sufficiently firm to hold the concrete, no other forms are necessary. Forms, wherever possible, should be constructed with the view to their repeated use. All forms should be substantially constructed and held in place, so as to permit no deflection or vibration, Page 57. nor any leakage of cement while the concrete is being placed. Forms should remain in place until the concrete is thoroughly set, and in the case of liquid container structures, the forms should be allowed to remain at least seven days. Forms should be so constructed as to permit, of their ready removal without injury to the concrete. Waterproofing Concrete. Where waterproofing of concrete is necessary, and the methods are not specified, the methods for waterproofing should be determined on the job. Under ordinary conditions for temporary construction, where floors are subject to water or dampness, it is recommended that five per cent of hydrated lime be added to the concrete mixture and to the top coating. Steel Reinforcement. Where concrete contains steel reinforcement, the steel should have an ultimate strength of 55,000 to 70.000...