for Highway Construction Page 457 of 71 5 SECTION 584 – TEMP ORARY SHORING
584.01 Description.
Provide temporary shoring as required for the support of the existing and the new roadway adjacent to the construction area, including designing, furnishing, constructing, inspecting, testing, and monitori ng the temporary shoring system and removing the temporary shoring after the work is complete.
584.02 Materials.
Determine materials for temporary shoring and obtain Engineer approval before use.
584.03 Construction Requirements.
Select, and submit before construction, the proposed materials and the temporary shoring type, shop drawings , and design calculations prepared, signed, and sealed by an Idaho licensed professional engineer for approval. Ensure shop drawings are submitted and meet the requirements of 105.02. Include a live load surcharge where vehicular load is expected to act on the back fill surface within a distance equal to ½ the shoring height behind the back f ace of the shoring. The increase in horizontal pressure due to live load surcharge is equivalent to that produced by at least 2 feet of soil. Ensure the clear distance between temporary shoring and temporary guardrail is 2 feet or more. Design the temporary shoring in accordance with the AASHTO Guide Design Specifications for Bridge Temporary Works. The Department will not allow gravity walls (e.g., gravity block walls) to be used as temporary shoring when the excavation depth is greater than 10 feet. Include the following in the shop drawings :
1.Location and limits of the temporary shoring with respect to an existing or established survey line.
2.Plan, elevation, and section views includi ng necessary dimensions and elevations, showing all soil or rock layers with design parameters and top and bottom elevations (including groundwater elevation) that are the basis for the submitted design.
3.Excavation limits adjacent to shoring.
4.Type and size of materials and shoring components being used.
5.Erection, excavation, and removal sequence of the temporary shoring.
6.Location and limits of temporary guardrail .
7.Design notes including design criteria, loads, material specifications, and inspecti on, testing , and/or monitoring requirements.
8.Show temporary shoring installed in stages, if necessary, to accommodate other work activities. The Department advises the Contractor to review the Phase IV Materials Report or Geotechnical Engineering Report and the existing structure drawings for information on the soils and the existing foundation in the shored area.
9.Include specific elevations below which not to excavate before placing internal bracing or anchors and highest allowable ground surface elevation outside (behind) the temporary shoring system. for Highway Construction Page 458 of 715 584.04 Method of Measurement. The Engineer will measure acceptably competed work by the lump sum.
584.05 Basis of Payment .
The Department will pay for accepted quantities at the contract unit price as follows: Pay Item Pay Unit Temporary Shoring ................................................................................. LS Predrilling required for the selected shoring system is inc idental . for Highway Construction Page 459 of 715 SECTION 585 - RESERVED
Source: Idaho Standard Specifications for Highway Construction, 2023 Edition. Pages 493–494 of 768.