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Title: PREVENTION OF LANDSLIDES
Accession Number: 00235701
Record Type: Component
Abstract: RECOGNITION AND INVESTIGATION OF UNSTABLE AREAS IN THE DE- SIGN OF PREVENTIVE TREATMENT SHOULD BE CONSIDERED ESSENTIAL PHASES OF THE PRELIMINARY PLANNING AND DESIGN OF ANY PROJECT ON WHICH THE PROPOSED CONSTRUCTION MIGHT INDUCE LAND MOVE- MENTS. THE PREVENTION OF INCIPIENT OR POTENTIAL LANDSLIDES REQUIRES: (1) RECOGNITION OF THE HAZARD WHICH MAY NOT BE AT ALL EVIDENT FROM SUPERFICIAL EXAMINATION, (2) ANTICIPATION OF THE CHARACTER AND MAGNITUDE OF MOVEMENT WHICH MAY OCCUR, AND (3) DESIGN OF SUITABLE TREATMENT WHICH WILL PREVENT ANY LAND MOVEMENT DURING OR FOLLOWING THE PROPOSED CONSTRUCTION. THE ROADWAY SLIPOUT IS PARTICULARLY TROUBLESOME TO HIGHWAY ENGINEERS. THIS IS A LANDSLIDE WHICH OCCURS AT OR BELOW ROADWAY GRADE, WITH A PORTION OR ALL OF THE ROADBED MOVING DOWNWARD AND OUTWARD. THIS CHAPTER CONSIDERS ONLY THOSE EMBANKMENT SLIPOUTS IN WHICH THE SURFACE OF RUPTURE IS WHOLLY OR PARTIALLY IN ORIGINAL GROUND BENEATH THE FILL. PREVENTION OF ALL TYPES OF LANDSLIDES MAY BE ACCOMPLISHED BY ONE OR MORE OF THE FOLLOWING METHODS: (1) REDUCTION OF ACTIVATING FORCES, (2) INCREASING THE FORCES RESISTING MOVEMENT, AND (3) AVOIDANCE OR ELIMINATION OF THE SLIDE. REDUCTION OF THE ACTIVATING FORCES CAN BE ACCOMPLISHED BY 2 GENERAL METHODS: REMOVAL OF MATERIAL FROM THE PORTION OF THE SLIDE WHICH PROVIDES THE DRIVING FORCE TENDING TO CAUSE MOVEMENT, AND SUBDRAINAGE TO ELIMINATE HYDROSTATIC PRESSURE AND/OR TO DIMINISH THE WEIGHT OF THE SOIL MASS BY REDUCING MOISTURE CONTENT. THERE ARE MANY METHODS FOR INCREASING THE FORCES RESISTING SLIDE MOVEMENT, INCLUDING THE FOLLOWING: (1) SUBDRAINAGE, IN ORDER TO INCREASE THE SHEAR RESISTANCE OF THE SOIL, (2) ELIMINATION OF WEAK ZONES OR POTENTIAL SURFACES OF RUPTURE BY STRIPPING OR BREAKING UP OR BENCHING OF SMOOTH OR WEAK SURFACES, (3) CONSTRUCTION OF CONSTRAINING STRUCTURES, SUCH AS PILES, WALLS, CRIBS, OR TOE SUPPORT FILLS, AND (4) SOLIDIFICATION OF LOOSE GRANULAR MATERIAL BY CHEMICAL TREATMENT. THE MOST ECONOMICAL METHOD OF PRE- VENTING LANDSLIDES IS BY AVOIDANCE. THE METHODS BY WHICH THIS MAY BE ACCOMPLISHED INCLUDE: RELOCATION OF THE PROPOSED HIGHWAY OR STRUCTURE TO AVOID UNSTABLE TERRAIN, COMPLETE REMOVAL OF AN EXISTING SLIDE; OR BRIDGING THE UNSTABLE AREA. THE VARIOUS TREATMENTS ARE COMPARED AND EVALUATED. THE DISCUSSION SHOWS THAT THERE IS NO RULE-OF-THUMB SYSTEM OF PRESCRIBING TREATMENT. FREQUENTLY THE MOST ECONOMICAL MEANS OF PREVENTION CONSISTS OF A COMBINATION OF TWO OR MORE OF THE PREVENTIVE MEASURES.
Supplemental Notes: pp 113-149, 31 FIG, 1 TAB, 11 REF Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
Monograph Title: Monograph Accession #: 00234453
Authors: Root, A WPublication Date: 1958
TRT Terms: Uncontrolled Terms: Old TRIS Terms: Subject Areas: Geotechnology; Highways; Security and Emergencies
Files: TRIS, TRB
Created Date: Aug 17 1970 12:00AM
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