MOU - Jagdish Easement Kern Rd. & Michigan St. - AEP

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Page 20 of 24 Construction Specification for the Installation of Steel Poles Rev. 1 TLCS-1402 Specification still plumb, non-shrink grout meeting the criteria of ASTM C1107 shall be placed within 72 hours by tremie until it completely fills the voids around the aggregate. The ultimate compressive strength of the grout shall be a minimum of 4,000 psi when tested in accordance with ASTM C109. 10.4 Concrete Backfill All material and test equipment shall be furnished by the Constructor. Direct embedded poles with concrete backfill shall be subject to the following time requirements for supporting the structure during concrete curing and the start of wire stringing activities. These requirements are in place to ensure that concrete strength is adequate to handle loads imposed from construction activities during the curing process. It is imperative to understand the strength of the concrete backfill assumed in the foundation design to appropriately apply this requirement. Concrete backfill for direct embedded poles shall be tested for the first five truck loads. Concrete testing shall be performed in accordance with TECS-4001 except as noted here. Initial testing shall include cylinders taken for installations performed on a minimum of two separate work days. If a project scope can be completed in one day, the two-day requirement may be ignored. For concrete placement associated with the first five concrete truck loads, the Owner’s Engineer shall provide the required duration for supporting the structures during concrete pouring and curing, as well as the required cure time prior to wire stringing activities. Criteria for determining these durations may include historical concrete break records for the mix design being used on the project. In circumstances where concrete strength is critical, durations may extend until the first breaks confirm the required strength. The initial testing shall be used to determine time requirements for supporting structures during concrete curing, as well as the time required before wires can be strung to the structure(s). Acceptance criteria for ongoing direct embed foundations with concrete backfill shall be based on an average of the break records establish in the initial test population. This may require additional concrete cylinders to be taken at each location. Table 3: Construction Activity and Associated Concrete Design Strength Construction Activity: Design Strength Threshold: Support the pole/pole section 75% Wire stringing 100% The Owner’s Engineer may approve time requirements, based on strength thresholds other than those stated in this document via written acknowledgement that those strengths are sufficient to support loads imposed during construction. Ongoing concrete testing is required to show that established construction activity durations remain adequate throughout the project length and timeline, including weather/seasonal variations and geologic variation. At a minimum, concrete at every tenth truck load shall be tested after the initial sampling