TIC 2017-02-28 Item 2B - Agreement - 2017 Bridge Repairs and Maintenance: On-Call Engineering Support with TranTech Engineering

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service or if additional rehabilitation is needed to attain a safe load carrying capacity. The analysis will also assess the feasibility of future repairs. The Green River Pedestrian and Utility Bridge was repaired and protected in a 2007 maintenance contract but its timber elements are currently in need of recoating. TRANTECH will use existing inspection information and will perform a routine inspection of the bridge to determine if any additional repairs are necessary prior to the recoating process. 1.1 In -depth Inspection The substructure of the 119`h Street Bridge has not had a recent underdeck and substructure inspection. TRANTECH will provide a hands -on inspection of the underside of the deck, floor system, and piers by use of rope assisted climbing. The condition of the elements will be evaluated and updated in the WSBIS Bridge Inspection Software. The resulting condition information will then be utilized in Task 1.2 to calculate the current capacity of the bridge. The in -depth condition assessment will also be reported in the resulting feasibility report listed below as the Task 1 deliverable. 1.2 Bridge Load Rating TRANTECH will provide a bridge load rating of the 119`h Street Pedestrian Bridge using the results of the in -depth inspection completed in Task 1.1. This as- repaired capacity will take into account the maintenance work done to date. This load rating will assess the current adequacy of the bridge for continued service as well as the feasibility for repairs that may add dead load such as deck overlay options yet to be determined. The initial scope of the load rating is assumed to be for a superstructure rating only. The scope of the load rating may be expanded to include the substructure if deemed necessary after the inspection and by additional scope and budged as approved by the City. TRANTECH will assess any new deterioration found on the Green River Pedestrian and Utility Bridge using analytical tools and information made available by our previous work done during the 2007 repair and coating contract. It is assumed that climbing of this bridge is not necessary based on the relatively recent rehabilitation contract. It is also assumed that the current load rating is still valid and that no update is necessary. A load rating update will be performed if deemed necessary and by additional scope and budged as approved by the City. In the case that any of either Bridge's critical elements have load carrying deficiency, viable strengthening means will be proposed as part of Task Section 1.3. 1.3 Repair and Strengthening Options TRANTECH will provide a report presenting the results of the inspection and structural analysis based on the activities described in Task Sections 1.1 and 1.2. This report will provide Tukwila with necessary decision making information about the feasibility of possible repair options. The report will also indicate if all element capacities are greater than the demand allowing the City to choose rehabilitation activities that will include only "element protection measures" for service life extension. As a non -NBI bridge, federal requirements do not apply. TRANTECH will work Tukwila Bridge Program Engineering Support -- SCOPE OF WORK Page 2 TRANTECH ENGINEERING 13