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HARBOR BLVD. MIXED USE TRANSIT CORRIDOR PLAN FINAL FIR <br />CITY OF SANTA ANA <br />5. Environmental Analysis <br />NOISE <br />Vibration - Induced Architectural Damage <br />Building damage is not a factor for normal projects, with the occasional exception of blasting and pile driving <br />during construction (FTA 2006). According to Caltrans, extreme care must be taken when sustained pile <br />driving occurs within 25 feet of any building. The thresholds at which there is a risk of architectural damage <br />is 0.5 m /sec PPV for reinforced concrete, steel, or timber buildings, and 0.2in /sec PPV for wood framed <br />structures, including historic structures. Vibration levels from typical construction equipment are shown in <br />Table 5.9 -9. <br />Table 5.9 -9 Construction Equipment Vibration Levels <br />Equipment <br />Approximate RMS' Velocity <br />Level at 25 Feet <br />(VdB) <br />Approximate PPV <br />Velocity at 25 Feet <br />(in /sec) <br />Pile Dover (impact) Upper Range <br />112 <br />1.518 <br />Pile Dover (impact) Lower Range <br />104 <br />0.644 <br />Pile Dover sonic Upper Range <br />105 <br />0.734 <br />Pile Dover sonic Lower Range <br />93 <br />0.170 <br />Vibratory Roller <br />94 <br />0.210 <br />Large Bulldozer <br />87 <br />0.089 <br />Caisson Drilling <br />87 <br />0.089 <br />Jackhammer <br />79 <br />0.035 <br />Small Bulldozer <br />58 <br />0.003 <br />Loaded Trucks <br />86 <br />0.076 <br />FTA Criteria: Human Annoyance Da time <br />78 <br />— <br />FTA Criteria: Architectural Damage <br />— <br />0.200 Wood - Framed <br />0.500 Reinforced Masonry <br />Soumz: FfA M. <br />1 RIMS velocity calculated from vibration level (VdB) using the reference of 1 micrctndi /second and arrest factor of 4. <br />This is a program level analysis, and no site - specific development is being proposed at this time. Therefore, <br />the precise locations of demolition and construction activities and type of construction equipment is <br />unknown, but would be determined for each individual project within the Harbor Corridor Plan. Depending <br />on distance and the equipment used, vibration levels could potentially exceed the 0.5 in /sec vibration induced <br />architectural damage threshold for reinforced masonry buildings and the 0.2 m /sec criteria for wood - framed <br />buildings. If future, individual projects under the Harbor Corridor Plan exceeded these thresholds, vibration - <br />induced architectural damage impacts would be significant. <br />Vibration Annoyance <br />As discussed above, the nearest sensitive receptor structures subject to annoyance from the construction of <br />individual projects are existing and future residential uses in and adjacent to the project area. Levels of <br />vibration produced by construction equipment are based on the FTAs significance threshold for vibration <br />annoyance of 78 VdB for barely perceptible levels of vibration during the daytime (note that construction <br />would be limited to daytime hours to comply with the City's municipal code). Table 5.9 -9 shows the potential <br />vibration levels (VdB) that can be generated by heavy construction equipment at receptors 25 feet away. As <br />October 2014 Page 5.9 -15 <br />