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Maintenance of Waterfront Structures


Quiz Questions

1.All timber products should be pressure treated with an appropriate preservative. The choice of preservative depends on how the timber is to be used ( pile, cap, stringer, decking, etc.) and what kind of climate exists where the installation is to be made.
True
False
2. Which one of the following is wood destroying organism.
Fungi
Marine Borer
Termites
All of the above
3.The 2 major type of decay fungi produce two kinds of decay, brown rot and white rot.
True
False
4.Brown rot causes wood to shrink, collapse and crack across the grain.
Ture
False
5.Improper finishing or curing practices can cause craze cracking of the concrete
True
False
6.Before planning a repair job it is essential to determine the cause of the problem: the concrete itself, the structural assembly, or both.
True
False
7.Concrete that it is stressed under loads must be supported properly before the defective portions are cut away. The load on the beams must be removed, and/or the beam relieved of its structural load by shoring to avoid deflection. In the repair of piles that are small in cross section, if the removal of defective concrete could be detrimental to the stability of the structures, an attempt should be made to relive part of its load.
True
False
8.Cast-in-place method of restoring concrete should be used when

Holes extend through the concrete section
Holes in un-reinforced concrete are more than 1 square foot in area and over 4 inches deep

Holes in reinforced concrete are more than ½ square foot in area and deeper than reinforcing steel
True
False
9.If a masonry quaywhall or graving dock has moved as the result of a sliding at the foundation, a structural analysis to determine the cause is necessary before any restoration is attempted. An Investigation of the settlement may involve pumping dyed water through cracked or leaky joints to determine the extent of hidden cavities or voids; the existence of a cavity would be confirmed by finding the colored water at some drainage outlet.
True
False
10. Riprap is a mixed assemblage of rubble, either dumped indiscriminately ( as a foundation for the water front structure) from scows and barges or deposited on the surface of a mound to protect the mound against erosion by waves and scouring by tidal action and underwater currents.
True
False
11. The major maintenance requirment for earth-filled waterfront structures consists of preventing the soil from being eroded and replacing the soil when a loss is discovered. This means maintaining sufficient riprap or slope protection on side slopes insuring the integrity of soil-containing structures, such as sheet pie cofferdams, timber or concrete paneled quaywalls, etc.
True
False
12.Repair of holes in the side of floating structures, such as floatings, lifts, and camels, should be made by welding on steel plates. The plates should be rounded and the welding ba as smooth as possible to avoid conditions which accelerate corrosion.
True
False