Laserfiche WebLink
<br />68 <br /> <br /> <br />TREATED MATERIALS <br /> <br /><:,'. ~. .' . '. " ,'.', o', ,..,... <br />" : V' '0',:0. .toj; ',.;.. .~.~. ~.'" <br />.'O',,>.b.::.,,,. "X...,q"":'HO <br />.- ." ....... . . <br /> <br /> <br />Figure 7,14, Use of treated building materials for protection against deterioration. <br /> <br />Protection of concrete from groundwater may be required for 14 calendar days after place- <br />ment. Where groundwater conditions make this necessary, the groundwater may be tem- <br />porarily removed or a temporary membrane may be used, <br /> <br />The above discussion of waterproofing is intended to serve as guidelines for "completely <br />dry" waterproofed construction. Essentially dry construction is another alternative. By defini- <br />tion, essentially dry means a maximum of four (4) inches of water depth may accumulate in <br />a space during a 24-hour period if no water is removed. However, sump pumps should be <br />used when this rate of seepage occurs, Essentially dry construction may be upgraded to com- <br />pletely dry construction by adding external or internal continuous membranes. <br /> <br />7.4 Levees <br /> <br />In some locations, it may be economically unfeasible to adequately flood proof each struc- <br />ture near a river. I n such areas, a levee system may be the best means of protection from <br />floodwaters. Levees are embankments which prevent a flood from reaching a structure or <br />land area, The fill that is used must be capable of resisting the imposed loads after it is pro- <br />perly placed and compacted, A freeboard allowance must be incorporated in the design of a <br />levee (Table 1), <br /> <br />Two of the factors that must be investigated when constructing a levee are slope stability <br />and erosional effects. They will require soil testing and determination of water forces and <br />velocities. Slope stability and erosion are discussed in Chapter VI. <br /> <br />The availability of suitable fill material is another important concern. The borrow area should <br />be at or near the construction site, and the material should be tested before it is approved <br />for use. Foundation material must also be tested to determine its characteristics. The proper- <br />ties of both fill and foundation materials will help to determine what seepage and drainage <br />control measures, if any, should be used, <br /> <br />.I <br />