PHASE ONE – EARLY CONSTRUCTION WORK
WATER EMERGENCY TRANSPORTATION AUTHORITY
DOWNTOWN FERRY TERMINAL EXPANSION
SAN FRANCISCO, CALIFORNIA
SECTION 01 32 00 - DOCUMENTATION STRUCTURAL INSTRUMENTATION AND MONITORING
PART 1 - GENERAL
1.1 SUMMARY
A. Section includes requirements of documentation, instrumentation, and monitoring of existing conditions prior to beginning selective demolition and construction activities to minimize, limit, and mitigate impacts of construction-related deformation on buildings, other structures, and utilities. This includes implementation of mitigation measures before, during, or after construction for the specific situation in addition to those called for in the MMRP Appendix 12 of the Contract for Construction.
B. This requirement to minimize, limit, and mitigate impacts has the following major elements:
a. A Pre-Construction Condition Survey documenting existing conditions and baseline elevations of floor and ground levels of buildings, structures and sidewalks.
b. Weekly condition monitoring during construction to identify any changes that may result or be caused by construction activity.
c. A Post-Construction Survey documenting the condition of buildings, structures, sidewalks and utilities, after Substantial Completion of construction.
d. Comprehensive Instrumentation and Monitoring: Instrumentation and monitoring of buildings, structures, sidewalks and utilities, as required in this section.
e. A list of buildings, structures, sidewalks and utilities to be documented and monitored is included in Section 1.3.
C. Related Work:
1. Section 01 30 00: Administrative requirements.
1.2 DEFINITIONS
A. Alert Level – The deformation that will trigger the need for cautionary measures increased monitoring frequency, and other actions in accordance with the Action Plan.
B. Allowable Deformation Tolerance – The maximum horizontal, vertical, and/or rotational movement of a given type of structure before a response level is triggered. Threshold values given in Section 3.1.
C. Buildings – “Buildings” refers to existing buildings within influence zone of the Project.
D. Ground Movement – Collectively refers to vertical and horizontal deformation of the ground.
E. Other Structures – Includes the following:
1. Street and sidewalk pavements, curbing and all drainage appurtenances.
F. Response Levels – Comprised of “Alert Level” and “Trigger Level.”
G. Structures – As defined herein, refers to “Buildings” and “Other Structures.”
H. Trigger Level –The deformation at which no further deformation will be acceptable. The second and greater response level that stops the construction and necessitates mitigative action to halt settlement and avoid damage to existing structures.
I. Utilities – Refers to existing underground and surface. Underground utilities along with associated manholes include gas, water, electric power, steam, communications, cable, drainage, and sewer.
1.3 RequireD DOCUMENTATION, INSTRUMENTATION AND MONITORING for Buildings, Other Structures, SIDEWALKS and Utilities
A. The buildings, other structures, and utilities that may be affected by construction include the following:
a. The Agriculture Building.
b. Adjacent ferry terminals.
c. The Ferry Building areas within 75 ft of any pile driving activities to Project.
d. The seawall and adjacent BART Platform (Ferry Plaza) within 75 ft of any pile driving activities.
e. Street and sidewalk pavements, curbing, areaways, manholes, vaults, and other infrastructure within 75 ft of any pile driving activities, or to the east curb of the Embarcadero whichever is greater.
f. All utilities within 75 ft of any pile driving activities, or to the east curb of the Embarcadero whichever is greater.
1.4 BUILDING AND OTHER STRUCTURE EXISTING CONDITION ASSESSMENTS
A. Pre-Construction Condition Survey of Buildings and Other Structures
1. Prior to the commencement of vibration or settlement-producing activity, the Contractor shall undertake a comprehensive pre-construction survey.
2. The surveys shall include,
a. A “before” condition survey of the buildings and structures. The survey shall include at a minimum a visual inspection of the exteriors and interiors of the buildings and other structures, recording of the existing conditions by means of video, photographs, a level survey giving elevations (Project Datum) of the floor level, and adjacent ground levels at building entrances. The descriptions of the conditions shall be noted on building plans.
b. A photographic and level survey of the condition of sidewalks.
c. A mapping of existing surface and below-grade utilities based on field observations and information from utility service providers and the Port of San Francisco.
1.5 SUBMITTALS
A. General
1. Submit pre-construction condition surveys for each building, structure, the sidewalks and utilities in report format.
2. Submit map showing location of all underground utilities that may be affected by construction.
B. Monitoring Program and Records:
1. Submit detailed program for monitoring existing elevations, drift, and extent of damage.
2. Submit records indicating conditions at end of each week of construction operations.
3. Electronic Picture Files: Submit electronic USB 3.0 flash drives for each view required within five days of taking photographs.
1.6 QUALITY ASSURANCE
A. Photographer Qualifications: Firm or individual with not less than five-years successful experience in professional digital photography, file transfer protocol, and construction work.
1. Camera: Professional quality high resolution color digital camera with resolution of 10megapixels capable of producing photo quality photographs of 20” by 30” or greater.
B. Monitor Qualifications: Firm or individual with not less than five-years successful experience in monitoring using equipment required for accurate measurement of existing locations and conditions.
1. Monitoring Equipment: Measurement accuracy to not less than 0.01”.
1.7 PHOTOGRAPHIC IMAGES
A. Digital Images: Provide each photograph with following information stored in same file with photographs.
1. Information Files: Store PDF format with Name of Project, date and time photograph was taken, photographer, exact location and direction, description of image as necessary to differentiate each photograph.
2. Photograph File: Store as both JPEG file format and an approved noncompressed format capable of being edited and enlarged to degree appropriate to camera resolution. Metadata to include GPS coordinates.
1.8 REQUIRED PHOTOGRAPHS
A. Types of Photographs:
1. Adjacent Conditions: Provide photographs of adjacent conditions in both overall general views and with specific views indicating damage and deterioration of adjacent facilities and elements.
a. Photographs to allow for future review for damage which could have been caused by construction.
2. Existing Conditions: Provide photographs from various locations and in sufficient numbers to establish existing conditions prior to beginning Project.
a. Photographs to allow for verification of accurate restoration of Project components to original conditions and to indicate damage which could have been caused by construction.
3. Progress: Provide photographs to indicate progress of work on weekly basis during construction operations.
4. Completion: Provide photographs of completed work with exterior photographs showing each view of building and interior photographs indicating each major space, each principle object, and additional information as directed.
5. Changes: Provide photographs as necessary to describe Requests for Information and field conditions.
6. Special: Provide special photographs as required by Owner’s Representative of specific views, spaces, or objects.
PART 2 – PRODUCTS
NOT USED
PART 3 – EXECUTION
3.1 CONSTRUCTION PERFORMANCE REQUIREMENTS FOR SETTLEMENT MITIGATION
A. Monitoring Required
1. Monitoring Requirements: Include measurements of settlement, drift, and changes in existing damage that can be revealed by accurate measurement and documentation of existing conditions.
2. Types of Monitoring: Monitor adjacent structure locations at points where markers will not be disturbed by construction operations while ensuring accurate measurements to establish initial locations of Agriculture Building and other adjacent structures.
a. Use laser surveys to locate each approved marker and establish location with global positioning satellite (GPS) accuracy using marker capable of being monitored using GPS location during construction.
b. Monitor each marker for elevation and for exact location to allow monitoring of possible drift as well as change in elevation.
3. Existing Damage – Agricultural Building only: In addition to photographic documentation of existing damage, install crack monitor gages, such as the Avongard standard tell-tale crack monitor, at six locations. The crack monitor gages shall be capable of measuring horizontal movements of +/- 25 mm. and vertical movements of +/-10 mm. Fasten the gages over the cracks using screws or adhesives as recommended by the manufacturer. At the beginning of the pre-construction survey program, the contractor and Engineer will perform a site visit to determine the location of the gages.
B. Allowable Deformation Tolerances
1. Allowable deformation tolerances are as follows,
a. Agricultural Building and Ferry Building
1) Alert Level
a) Settlement: 0.5 inch, or,
b) Angular Distortion: L/600, (L is distance between settlement reference points, or major structure elements in inches).
2) Trigger Level
a) Settlement 0.75 inch, or,
b) Angular Distortion: L/400 (L is distance between settlement reference points, or major structure elements in inches).
b. Gravity Utility Systems
1) Settlement: 0.5 inch
c. Other utilities
1) Upon report of leaks or disruption of utility services.
C. Response Level Actions
1. Alert and Trigger Levels are given below. Ranges for Monitoring Conditions – color-coded to reflect status as follows:
a. Green Range: Below Alert Level.
b. Yellow Range: Range between Alert and Trigger Level.
c. Red Range: Trigger Level and above.
2. If an Alert Level is reached: Notify Owner’s Representative to address the need for response action(s).
3. If the Owner’s Representative indicates a response action is needed, submit, within 24 hours of first notice, that Alert Level has been reached, along with a detailed specific plan of action.
4. If directed by the Owner’s Representative, implement response action(s) within 24 hours of submitting a detailed specific plan of action.
5. Install additional instruments if directed by the Owner’s Representative.
6. Take all necessary steps so that the Trigger Level is not reached. Contractor may be directed to suspend activities in the affected area with the exception of those actions necessary to avoid reaching the Trigger Level.
7. If a Trigger Level is reached: Stop work if construction may result in continued movement or further damage.
8. a.
Convene a meeting with the Owner’s Representative to discuss the response action(s) required.
b. If the Owner’s Representative indicates a response action is needed, submit within 8 hours of first notice of reaching a Trigger Level, a detailed specific plan of action.
c. If directed by the Owner’s Representative, implement response action(s) before resuming work.
9. The responsibility of the Contractor is to identify actions that need to be taken for construction of the project that will reduce damage and settlement risk. The Owner, in conjunction with the Port of San Francisco, will be responsible for allocating costs associated with implementing the plan of action.
END OF SECTION
Issued for Bid: September 30, 2016 Documentation, Instrumentation, and Monitoring
Phase One – Early Construction Work 01 32 00 - 7