Part II. Pad foundations are isolated foundations that 1) _____ concrete column or free-standing brick piersPad foundations are isolated foundations that 1) _____ concrete column or free-standing brick piers. A square concrete pad foundation distributes the load evenly over the ground. If the pad is constructed of mass concrete, then the 2) _____ must equal the projection from the side of the column (Figure 8.6).
Figure 8.6 Pad Foundation
Stepped foundations are built on 3) _____ sites (Figure 8.7). This reduces the expense of constructing a foundation that is the same level around the perimeter of the building. A foundation at the higher end of the slope would be 4) _____ deep.
Figure 8.7 Stepped Foundation
To overcome this, the foundations should be stepped at 5) _____ levels. The higher-level foundation should 6) _____ over and meet with the lower one for a distance not less than its thickness. This should never be less than 300 mm. The change in level should not be more than the thickness of the strip foundation. It should be measured in multiples of 75 mm, which is the height of a 7) _____ course. If soil conditions are poor near the surface, then piled foundations should be used. Trial holes will usually indicate the depth of suitable load-bearing soil. Since this may be as deep as 2 or 3 metres below ground, it would be quite expensive to construct 8) _____ foundations. To overcome this problem two types of piled foundation can be used to strengthen the soil: a) bored or replacement piles, which are concrete 9) _____ poured into holes in the ground at measured intervals; b) driven or 10) _____piles, which are tree trunks that are hammered into soft ground at spaced intervals.
11 Fill in the gaps in the following passage with a suitable preposition given below:
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