My WebLink
|
Help
|
About
|
Sign Out
Home
Browse
Search
FLOOD04542
CWCB
>
Floodplain Documents
>
Backfile
>
4001-5000
>
FLOOD04542
Metadata
Thumbnails
Annotations
Entry Properties
Last modified
1/25/2010 6:46:32 PM
Creation date
10/5/2006 12:43:57 AM
Metadata
Fields
Template:
Floodplain Documents
County
Statewide
Basin
Statewide
Title
Engineering and Design Design and Construction of Levees
Date
4/16/1979
Prepared By
US Army Corps of Engineers
Floodplain - Doc Type
Educational/Technical/Reference Information
There are no annotations on this page.
Document management portal powered by Laserfiche WebLink 9 © 1998-2015
Laserfiche.
All rights reserved.
/
172
PDF
Print
Pages to print
Enter page numbers and/or page ranges separated by commas. For example, 1,3,5-12.
After downloading, print the document using a PDF reader (e.g. Adobe Reader).
Show annotations
View images
View plain text
<br />e <br /> <br />~ <br /> <br />, <br /> <br />e <br /> <br />. <br /> <br />" <br /> <br />e <br /> <br />EM 1110-2-1913 <br />31 Mar 78 <br /> <br />CHAPTER 4 <br /> <br />BORROW AREAS <br /> <br />4-1. General. In the past borrow areas were selected largely on the <br />basis of material types and quantities and haul distances. Today, <br />borrow areas receive much more attention and must be carefully planned <br />and designed, because of considerations such as environmental aspects, <br />increasing land values, and greater recognition of the effects of borrow <br />areas with respect to underseepage, uplift pressures, overall levee <br />stability, and erosion. The following paragraphs discuss some factors <br />involved in locating and using borrow areas. <br /> <br />4-2. Available Borrow Material. <br /> <br />a. Material TYPe. Almost any soil is suitable for constructing <br />levees, except very wet, fine-grained soils or highly organic soils. In <br />some cases, though, even these soils must be used. Accessibility and <br />proximity are often controlling factors in selecting borrow areas, <br />although the availability of better borrow materials involving somewhat <br />longer haul distances may sometimes lead to the rejection of poorer but <br />more readily available borrow. <br /> <br />b. Natural Water Content. Where compacted levees are planned, it <br />is necessary to obtain borrow material with water content low enough to <br />allow placement and adequate compaction. The cost of drying borrow <br />material to suitable water contents can be very high, in many cases ex- <br />ceeding the cost of longer haul distances to obtain material that can be <br />placed without drying. Borrow soils undergo seasonal water content <br />variations; hence water content data should be based on samples obtained <br />from borrow areas in that season of the year when levee construction is <br />planned. Possible variation of water contents during the construction <br />season should also be considered. <br /> <br />4-3. General Layout. Generally, the most economical borrow scheme is <br />to establish pits parallel and adj~cent to the levee. If a levee is <br />adjacent to required channel excavation, levee construction can often <br />utilize material from channel excavation. Large centralized borrow <br />areas are normally established only for the construction of urban levees, <br />where adjacent borrow areas are unavailable. Long, shallow borrow areas <br />along the levee alignment are more suitable, not only because of the <br />s):lorter haul distance involved, but also because they better satisfy <br />environmental considerations. <br /> <br />4-1 <br />
The URL can be used to link to this page
Your browser does not support the video tag.