243.02 Materials.
235.04 Method of Measurement.
No direct measurement or payment will be made for a detour bridge unless it is listed in the pay items of the contract. The detour bridges listed in the proposal will be identified by the station number of its location and measured as a Lump Sum Unit.
235.05 Basis of Payment.
243.01 Description.
This section covers the installation of geosynthetic soil reinforcement for the reinforcement of soil slopes and for soft soil stabilization. A "geosynthetic soil reinforcement" mate rial shall be any planar geosynthetic (geogrid or geotextile) material designed for the purpose of improving the shear strength of the soil matrix.
243.02 Materials.
The geosynthetic reinforcement (either geogrid or geotextile) shall be constructed of poly ester, polypropylene, or polyethylene polymer, resistant to all naturally occurring alkaline and acidic soil conditions, resistant to heat, ultraviolet light, and to attack by bacteria and fungi in the soil. Applicable test methods for measuring strength a nd creep are: • ASTM D 4595 "Standard Test Method for Tensile Properties of Geotextiles by the Wide- Width Strip Method" • ASTM D 5262 "Standard Test Method for Evaluating the Unconfined Tension Creep Behavior of Geosynthetics" • ASTM D 6637 "Standard Test Method for Determining Tensile Properties of Geogrids by the Single or Multi -Rib Tensile Method"
243.03 Receipt, Inspection and Certification.
Reinforcement for soil slopes shall be any geosynthetic whose strength in the machine direction equals or exceeds the values shown in the following table: SOIL SLOPE REINFORCEMENT TYPE CREEP REDUCED STRENGTH AT A 10 % TOTAL STRAIN LIMIT (minimum) pounds per foot {kN/m} TEST METHOD * 1 1000 {14.6} ASTM D 5262 2 2500 {36.5} 3 3400 {49.6} * Ultimate Strength measured in accordance with ASTM D 4595 or D 6637. Reinforcement for soft soil stabilization shall be any geosynthetic whose strength equals or exceeds values shown in the following table: SOFT SOIL STABILIZATION REINFORCEMENT TYPE ULTIMATE STRENGTH, MACHINE DIRECTION (minimum) pounds per foot {kN/m} ULTIMATE STRENGTH, CROSS MACHINE DIRECTION (minimum) pounds per foot {kN/m} STRENGTH AT 5% STRAIN, MACHINE DIRECTION (minimum) pounds per foot {kN/m} STRENGTH AT 5% STRAIN, CROSS MACHINE DIRECTION (minimum) pounds per foot {kN/m} TEST METHOD 1 900 {13.1} 900 {13.1} 500 {7.3} 500 {7.3} ASTM D 6637 ASTM D 4595 2 1300 {19.0} 1300 {19.0} 800 {11.7} 800 {11.7} 3 2100 {30.7} 2100 {30.7} 1200 {17.5} 1200 {17.5}
243.03 Receipt, Inspection and Certification.
Reinforcement geosynthetics delivered to ALDOT projects shall be packaged, identified, stored, and handled in accordance with the requirements given in ASTM D 4873 "Standard Guide for Identification, Storage, and Handling of Geosynthetic Rolls and Samples". Each roll of delivered mat erial shall be individually marked to permit direct correlation with the applicable production Lot Number. Delivered material shall be accompanied by a manufacturer certified copy of test results (ASTM D 4595 for Geotextiles or ASTM D 6637 for Geogrids) ve rifying the ultimate strength of the Lot(s) from which delivered rolls of reinforcement were obtained. Deliveries of reinforcement that are improperly packaged, marked and/or lack manufacturer certified Lot test results (ASTM D 4595 for Geotextiles or ASTM D 6637 for Geogrids) will not be accepted by the Project Manager . One sample per reinforced slope sha ll be taken in accordance with Acceptance Sampling and Testing Schedule Section 605.
243.04 Construction Requirements.
All areas immediately beneath the installation area for the geosynthetic reinforcement shall be properly prepared as detailed on the plan s, specified elsewhere within the specifications, or directed by the Engineer. In general, the reinforcement shall be installed in accordance with the manufacturer’s recommendations and shall be placed within the layers of the compacted soil as shown on th e plans or directed. Only that amount of geosynthetic reinforcement required for immediately pending work shall be placed to prevent undue damage to the reinforcement. After a layer of geosynthetic reinforcement has been placed, suitable means such as pins , small piles of soil, or other fixation means as recommended by the manufacturer shall be used to hold the geosynthetic reinforcement in position until the subsequent soil layer can be placed. Under no circumstance shall a track -type vehicle be allowed on the reinforcement before at least 8 inches {200 mm} of soil have been placed on the reinforcement. Soil layers shall be constructed in accordance with Section 210. The overlapping of the geosynthetic reinforcement shall be as required by the plans. If a specific overlap is not required by the plans, individual pieces of reinforcement shall typically be installed side by side with the “machine direction” of the material oriented in the direction of required reinforcement. When the delivered width is greate r than the width of geosynthetic reinforcement required, the reinforcement may be cut with a razor, knife, abrasion saw, or similar tool. As an alternate to cutting,
250.03 Construction Requirements.
the Contractor may be allowed to turn the excess portion of the reinforcement under, provi ded an acceptable installation is obtained. That portion of reinforcement cut off or turned under will not be measured for payment. If a geotextile is required in conjunction with one or more layers of geosynthetic reinforcement, it shall be installed as shown on the plans or directed by the Engineer.
243.05 Method of Measurement.
The quantity of geosynthetic soil reinforcement, measured for payment, will be the number of square yards {square meters} of material installed and acceptably placed. No measureme nt will be made for portions cut off, overlaps, or portions not needed but allowed to remain in the fill.
243.06 Basis of Payment.
250.01 Description.
This Section shall cover the removal and disposal of underground storage tanks for petroleum based hydrocarbons and the removal and disposal of contami nated soil. The term underground storage tank (UST) includes the UST and all components (pump lines, vent lines, distribution lines, etc.) of the tank. This Section shall also cover the removal and disposal of the contents of the UST and the backfilling of the areas of removal. The approximate extent of the known contamination will be shown on the plans. The actual limits of contamination will be determined in the field with verification sampling at the time of UST removal. The treatment of groundwater after the removal of the USTs will be done under a separate contract.
250.02 Materials.
Material requirements are not given for the work required under this Section. The furnishing and placement of materials is covered under other Sections.