WALL APPLICATION
734.01 Description This work shall consist of designing an d constructing a permanent earth retention
system utilizing a cut-wa ll application in accordance with 105.03. Cut-wall applications refer to a class of earth rete ntion systems in which construction of the system is performed from the top of the wall to the base utilizing either externally or internally stabilized elements or a combination of both. Geotechnical Engineering Circular No. 2 – Earth Retaining Systems, Report No. FHWA-SA-96-038 provides 10 further discussion of cut-wall applications.
734.02 Contractor Design Requirements
The permanent earth retention system utilizing a cut-wall application shall be designed by a professional engineer having experience in the design of at least three completed permanent earth retention systems involving cut-wall applications. The permanent earth retention system shall be designed using the procedure described in the AASHTO LRFD Bridge Design Specifications, or in the FHWA-IF-03-017, Soil Nail Walls. The required partial safety factor s or allowable strength factors for Service Load Design, SLD, and load and resistance factors for LRFD, shall be in accordance 20 with the above-referenced publications. The minimum factor of safety for SLD global stability or minimum required LRFD global stability shall be in accordance with the above-referenced publications, unless specified otherwise. Structural design of an individual wall element not addressed in the FHWA report shall be designed in accordance with the AASHTO specifications . Geometric data and design criteria including shear strength parameters and unit weights for soil and rock, corrosion protection, internal and external drainage requirements, horizontal and vertical alignment of the wall, and all known site and construction constraints, wall facing, and facing architectural requirements shall be as shown on the plans. 30
734.03 Materials 190
Materials shall be in acco rdance with the following: Geotextile Under Riprap .............................................. 918.02 Pneumatically Placed Mortar....................................... 708 Reinforcing Bars .......................................................... 703 Steel H Piles ................................................................ 915.02 Steel Pipe Piles ............................................................ 915.01 Steel Sheet Piling ......................................................... 910.21 Structural Concrete ...................................................... 702 Structural Steel ............................................................ 910.02 200 Structure Backfill ........................................................ 904.05 Uncoated Seven-Wire Strand ...................................... 910.01(b)7 WWR, Smooth a nd Deformed..................................... 910.01 Drainage pipe shall be underdrain pipe in accordance with 715.02(d). CONSTRUCTION REQUIREMENTS
734.04 General Requirements Excavation and embankment shall be in accordance with 203. 210
Welding shall be in accordance with 711.32.
734.05 Performance Monitoring During Construction The program shall identify points of m onitoring interest, in accordance with
Geotechnical Engineering Circular No. 2 – Earth Retaining Systems, Report No. FHWA-SA-96-038, and the frequency of monitoring during and following construction of the wall. The program shall also include a baseline survey for points of monitoring interest. The Contractor shall notify the Engineer if indications of ground movement in the vicinity of the wall, increased size of old cracks, or separation of joints in structures, foundations, streets, or pave d or unpaved surfaces are observed. The Contractor shall monitor the performance of the wall and movements of buildings, roads, or other facilities within a distance of three times the excavation depth for the wall. If the Engineer determines that the movements exceed those anticipated for construction, the 734.05 858 Contractor shall take corrective actions n ecessary to arrest the movement or make repairs. Within 30 days after completion of the work, as-built drawings shall be submitted 230 to the Engineer. Revised design calculations, signed by the professional engineer, shall be provided for all design changes made dur ing the construction of the permanent earth retention system.
734.06 Performance Monitoring After Construction
Performance monitoring by the Contractor shall be accomplished during construction and for a period of one year from the date the Contractor has been relieved of further maintenance, as set out in th e final acceptance letter from the Department. The Contractor shall post a warranty bond for the performance monitoring that occurs after the Contractor has been relieved of further maintenance. The Contractor shall 240 make evaluations of the test and monitoring data and performance of the wall at the frequency defined in the approved performance monitoring program. The Contractor, if necessary during the monitoring period or as directed, shall correct deficiencies in the capacities of individual elements or take other corrective measures which may be required to prevent damage or excessive movement of the wall and adjacent facilities. The Contractor shall submit all test and monitoring data to the Engineer on a weekly basis or as otherwise directed.
734.07 Method of Measurement
Cut wall will be measured by the square foot of exposed face area of wall above 250 finished grade as shown on the plans.
734.08 Basis of Payment
The accepted quantities of cut wall will be paid for at the contract unit price per square foot for cut wall. Payment will be made under: Pay Item Pay Unit Symbol Cut-Wall, No. ____ ................................................................... SFT The costs of all professional services, labor, excavation, structure backfill, equipment, materials, tests, and QCP shall be included in the cost of this work. All incidentals necessary to design, construct, and monitor the wall including all drainage required by the wall design and all temporary construction facing or permanent facing, if applicable, and correction required by the wall design of deficiencies which may be required to prevent damage or excessive move ment of the wall shall be included in the cost of this work. No additional payment will be made for the costs of providing and taking corrective actions. 270 734.06