Concrete Inspection (1909) (Paperback)

Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: CHAPTER III. INSPECTION OF FORM WORK. Forms are the molds in which the concrete is shaped to its purpose. They are constructed of wood or of steel; wood forms are most used. The cost of forms is a very large item in the cost of most kinds of concrete work; the contractor should, therefore, be assisted in every legitimate effort to make the greatest possible use of his forms. Safety must always come first, however; a great many concrete building failures have been chargeable to unwise handling of forms, particularly to the removal of forms before the concrete was hard and strong enough to carry its loads unsupported. The inspector should watch with care all portions of formwork having any bearing on safety. Forms being the molds in which the concrete is shaped, any error in dimensions or alignment means a corresponding error in the molded concrete member. The inspector should also make certain that the forms are perfect for their purpose in these respects. It should be accepted as a cardinal principle in form inspection that: The accuracy of no detail shall be taken for granted; it must be verified. Construction of Forms.?See that the construction of forms is such that they canbe removed without injury to the concrete, and that they can be erected accurately. Construction which necessitates the use of heavy crow-bars or hand sledging to take the forms apart is dangerous to the concrete. The best form construction is one in which the parts are assembled by means of clamps and wedges, and not by nails. Alignment of Forms.?See that all forms are erected in exact alignment, both vertically and horizontally; that column and wall forms are plumb; that girder boxes and wall forms are without winds or twists; that slab centers are level, etc. If the forms stand any considerable ti...