Sills and beams should be kept to a correct grade by the use of slate or steel shims and mortar pointing. Reinforcing plates, extra tie-downs, or other means should be used to correct misalignment. Timbers, exposed to ground moisture or severe weathering, must be treated often enough to prevent deterioration, and sufficient ventilation must be assured to avoid rotting.
To prevent periodic deterioration, thorough inspection should be made of all posts and columns in contact with the ground. They should be treated with a preservative to resist decay and damage by termites. Posts and columns should be maintained plumb and in alignment.
Inspection of posts should include a test for soundness, made by jabbing the post on all sides with an ice pick or other sharp instrument; the amount of penetration indicates the soundness of the wood. In most softwoods, such as pine and fir, the pick should penetrate more than one-half inch; in hardwoods, such as gum and oak, penetration should not exceed three-eighths inch. Columns are more difficult to inspect in finished buildings; but when there are indications that columns are out-of-plumb, the covering finish material should be removed and a thorough inspection made. Out-of-plumb or misaligned columns may be indicated by cracks in plaster or other finish, but the same defects may be caused by failure of other structural components. Repairs and/or replacement work should not be made until the true cause of defects has been established.
If the foundation is not level because of uneven settling, the defect should be corrected before any attempt is made to plumb or align posts or columns. The floor above should then be shored with jacks or other devices and the supporting members plumbed and realigned.
Posts or columns that show signs of failure caused by overloading should be surveyed by an engineer competent to recommend repairs or replacement in terms of overall structural soundness.
As the other basis supporting members, periodic inspection and timely repair of girders and joists are important to the general maintenance of a structure. Wood joists and girders are usually of a size that is not easily dried; consequently, it is normal to expect shrinkage and seasoning splits and checks.
Checks and splits should be carefully recorded as to size, location, and depth. If records indicate increase in length or depth, then stitch bolts may be required. Stitch bolts are required in all structural members that have deep checks or splits three-eights inch or greater in width and/or have slope of grain greater in width than 1 inch in 14 inches.
In the event of a structural failure, an engineering study should be made to determine whether the failure can be properly patched or if the entire girder or joist should be replaced. Many methods can be used to reinforce girders and joists. However, the selection of the proper methods should be determined by the loads to be carried, the cost, and clearance and accessibility. When either a permanent or temporary post is placed under a failure of a girder or joist, consideration of the size of the post and the cap, as well as adequacy of base support under the post, should be considered. Joist repair can be facilitated if the new member is sized one dimension smaller than the original member. Bridging that is removed should be replaced with solid bridging.
Floor materials found in shore establishment buildings and structures for various occupancies include wood, concrete, terrazzo, and clay tile. Common floor coverings include asphalt, vinyl tile, and linoleum.
Wood floors should be inspected quarterly for the following:
Warped, cupped, or loose boards
Damage from improper cleaning or condensation
Wood decayContinue Reading