PSA - Construction Inspection Services for Seitz Park Reconstruction Proj No. 117-093A - Lochmueller Group

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© 2020 SME P01657.20+092520 2 SCOPE OF SERVICES Based on our understanding of the project, we envision the vibration monitoring services will include the following 1. Prepare a vibration monitoring plan identifying the proposed locations of the portable seismographs relative to the proposed construction site and the ne arby existing buildings. Distribute the vibration monitoring plan to the project team for review and comment. 2. Perform a site visit to review the proposed monitoring locations, and make adjustments to the locations based on site-specific conditions. 3. Mobilize, maintain, and demobilize three (portable) remote monitoring seismographs. The portable seismographs are each equipped with a tri-axial geophone sensor, which connects to a main data processing and storage unit. Each sensor will be buried, or placed directly on the ground surface and covered with a sandbag, at the monitoring locations. Each data processing unit will be placed in a locked box with 1-foot long augers installed into the ground (or Hilti- anchored into the existing paved surface) to protect the equipment from weather and theft. 4. Coordinate the schedule for the installation and demobilization of each of the units with the Owner and the Contractor. We plan to perform one site visit to move the seismographs from Area A to Area B (or vice-versa) once the pile driving is completed in the one area, and prior to commencing the pile driving in the other area. 5. Provide remote vibration monitoring during the pile driving activities. The seismographs will be set up with remote transmission equipment to send an e-mail and/or cellular text message if the vibration levels (PPV’s) are recorded over a threshold level. The proposed threshold level is 0.25 inches per second (ips), and the proposed vibration limit level is 0.5 ips. We plan to have the vibration equipment triggers set for 0.25 ips. If the seismograph(s) is/are triggered, it will record a 0.25-second period prior to the trigger, and a 3-second period after the trigger to capture the general waveform of the vibration. The intent of recording the waveforms is to determine if an activity occurred that was a single isolated event (e.g., dropping equipment on the ground) or an intermittent transient event (e.g., pile driving). NOTE: We request information regarding the time/date of specific vibrations events be provided to us for review and comparison with the vibration measurements related to the specific events recorded by the seismographs. We also request SME be alerted prior to pile driving activities, particularly if those activities are expected to result in significant vibrations. The Contractor’s onsite personnel recording the date/time of the vibration events will need to sync up with the time recorded on the seismographs to enhance precision when relating vibration events to the vibration readings. 6. Provide a summary of the vibration measurements for each Area. The (two) summaries will include a general description of the vibration monitoring set up, peak vibration values recorded (in terms of peak particle velocity), select reports from each seismograph that represent our findings, and conclusions/comments regarding the potential impact the vibrations (from the pile driving) could have on the nearby existing structures. 7. Provide up to two hours of consultation regarding the findings from the seismographs. ASSUMPTIONS AND LIMITATIONS The following items are not included in our scope, but could be provided on a time and materials fee basis. 1. Additional visits to move seismograph locations (not including the visit for initial set up, an interim visit to move the seismographs from one Area to the other Area, and a final visit to demobilize ). 2. Based on the proximity of the seismographs to the proposed vibration inducing equipment, we have allotted for no more than one trigger above the 0.25 ips limit per seismograph, per week. In