11B0009-Specs-Amend0007.pdf

US ARMY ENGINEER DISTRICT, PHILADELPHIA

POC MARIA T. EVANS

100 PENN SQUARE EAST

PHILADELPHIA PA 19107

AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT

Except as provided herein, all terms and conditions of the document referenced in Item 9A or 10A, as heretofore changed, remains unchanged and in full force and effect.

15A. NAME AND TITLE OF SIGNER (Type or print)

30-105-04 EXCEPTION TO SF 30

APPROVED BY OIRM 11-84

STANDARD FORM 30 (Rev. 10-83) Prescribed by GSA

FAR (48 CFR) 53.243

THIS AMENDMENT DOES NOT EXTEND THE BID OPENING DATE OF 21 JUNE 2011 AT 11 A.M. EST

Please indicate receipt of this Amendment on Standard Form (SF) 1442 (SOLICITATION, OFFER, AND AWARD) as Amendment No. 0007.

Failure to acknowledge all amendments may be cause for rejection of the bid.

Continued On Next Page...

1. CONTRACT ID CODE PAGE OF PAGES

J 1

16A. NAME AND TITLE OF CONTRACTING OFFICER (Type or print)

16C. DATE SIGNED

BY

16B. UNITED STATES OF AMERICA 15C. DATE SIGNED 15B. CONTRACTOR/OFFEROR

(Signature of Contracting Officer) (Signature of person authorized to sign)

8. NAME AND ADDRESS OF CONTRACTOR (No., Street, County, State and Zip Code) X W912BU-11-B-0009

X 9B. DATED (SEE ITEM 11)

06-Apr-2011

10B. DATED (SEE ITEM 13)

9A. AMENDMENT OF SOLICITATION NO.

11. THIS ITEM ONLY APPLIES TO AMENDMENTS OF SOLICITATIONS

X The above numbered solicitation is amended as set forth in Item 14. The hour and date specified for receipt of Offer is extended, X is not extended.

Offer must acknowledge receipt of this amendment prior to the hour and date specified in the solicitation or as amended by one of the following methods:

(a) By completing Items 8 and 15, and returning copies of the amendment; (b) By acknowledging receipt of this amendment on each copy of the offer submitted;

or (c) By separate letter or telegram which includes a reference to the solicitation and amendment numbers. FAILURE OF YOUR ACKNOWLEDGMENT TO BE RECEIVED AT THE PLACE DESIGNATED FOR THE RECEIPT OF OFFERS PRIOR TO THE HOUR AND DATE SPECIFIED MAY RESULT IN REJECTION OF YOUR OFFER. If by virtue of this amendment you desire to change an offer already submitted, such change may be made by telegram or letter, provided each telegram or letter makes reference to the solicitation and this amendment, and is received prior to the opening hour and date specified.

12. ACCOUNTING AND APPROPRIATION DATA (If required) PHILADELPHIA NAVY SHIPYARD FLOOD REDUCTION PROJECT (SEAWALL REPAIR), PHILADELPHIA, PENNSYLVANIA

13. THIS ITEM APPLIES ONLY TO MODIFICATIONS OF CONTRACTS/ORDERS.

IT MODIFIES THE CONTRACT/ORDER NO. AS DESCRIBED IN ITEM 14.

A. THIS CHANGE ORDER IS ISSUED PURSUANT TO: (Specify authority) THE CHANGES SET FORTH IN ITEM 14 ARE MADE IN THE

CONTRACT ORDER NO. IN ITEM 10A.

B. THE ABOVE NUMBERED CONTRACT/ORDER IS MODIFIED TO REFLECT THE ADMINISTRATIVE CHANGES (such as changes in paying office, appropriation date, etc.) SET FORTH IN ITEM 14, PURSUANT TO THE AUTHORITY OF FAR 43.103(B).

C. THIS SUPPLEMENTAL AGREEMENT IS ENTERED INTO PURSUANT TO AUTHORITY OF:

D. OTHER (Specify type of modification and authority)

E. IMPORTANT: Contractor is not, is required to sign this document and return copies to the issuing office.

14. DESCRIPTION OF AMENDMENT/MODIFICATION (Organized by UCF section headings, including solicitation/contract subject matter where feasible.)

10A. MOD. OF CONTRACT/ORDER NO.

2. AMENDMENT/MODIFICATION NO. 5. PROJECT NO.(If applicable)

6. ISSUED BY

3. EFFECTIVE DATE

07-Jun-2011

CODE

US ARMY ENGINEER DISTRICT, PHILADELPHIA

CONTRACTING DIVISION

WANAMAKER BUILDING

100 PENN SQUARE EAST

PHILADELPHIA PA 19107-3390

W912BU 7. ADMINISTERED BY (If other than item 6)

4. REQUISITION/PURCHASE REQ. NO.

CODE W912BU

FACILITY CODE CODE

EMAIL: TEL:

Amendment No. 0007 Invitation for Bids

W912BU-11-B-0009

14. DESCRIPTION OF AMENDMENT (continued)

a. GENERAL NOTE - The following specification section has been amended. Blank pages have been provided in order to enable double-sided printing. All pages have been annotated with “Amendment No. 0007” in the header.

b. SPECIFICATION, Section 01 57 50 - MONITORING OF NATURAL GAS LINE - Please add new Pages 4 through 10 to the end of this spec section.

c. Please indicate receipt of this amendment on Standard Form 30 (AMENDMENT OF SOLICITATION/MODIFICATION OF CONTRACT) as Amendment No. 0007. Failure to acknowledge all amendments may be cause for rejection of the offer.

SAMPLE VIBRATION MONITORING PLAN

Pile Driving Procedures for Existing PGW Gas Mains and Other Critical PGW Gas Facilities

Philadelphia Gas Works Philadelphia, Pennsylvania

Section 01 57 50 Page 4

This page was intentionally left blank for duplex printing.

TABLE OF CONTENTS

1.0 PURPOSE

2.0 ASSESSMENT OF VIBRATION SUSCEPTIBILITY

2.1 Vibration Source Levels from Construction Equipment

2.2 Damage Assessment

2.3 Additional Considerations

3.0 FIELD VERIFICATION

4.0 SEISMOGRAPH INSTRUMENTATION AND RECORDING MODES

5.0 MONITORING LOCATIONS AND PLACEMENT

6.0 RECOMMENDATIONS AND CONCLUSIONS

7.0 LIMITATIONS

Section 01 57 50 Page 5

1.0 PURPOSE

This Vibration Monitoring Plan (VMP) has been prepared for Philadelphia Gas Works (PGW) for the proposed pile driving activities. The purpose of this VMP is to:

• Assess the vibration susceptibility of existing PGW gas mains and other critical PGW gas facilities, including estimated damage threshold particle velocity and acceleration.

• Minimize the risk of damage to existing PGW gas mains and other critical PGW gas facilities during pile driving activities and on-site operations that have the potential to generate elevated vibration levels by using seismic instrumentation monitoring within 100-foot of pile driving activities.

This VMP is intended to be used in conjunction with PGW Pile Driving Procedures.

2.0 ASSESSMENT OF VIBRATION SUSCEPTIBILITY

Construction activity can result in varying degrees of ground vibration, depending on the equipment and methods employed. Operation of construction equipment causes ground vibrations that spread through the ground and diminish in strength with distance. Buildings founded on the soil and underground utilities in the vicinity of the construction site respond to these vibrations, with varying results ranging from no perceptible effects at the lowest levels, low rumbling sounds and perceptible vibrations at moderate levels, and slight damage at the highest levels. The level of construction vibration analysis is determined by factors related to the scale of the project and sensitivity of the surrounding buildings and underground utilities.

Ground vibrations from construction activities do not often reach the levels that can damage structures and underground utilities, but they can achieve audible and motion ranges within close proximity to the area of activity. Special care and monitoring should be observed in the case of fragile buildings, buildings housing sensitive equipment, and underground utilities of undetermined condition.

2.1 Vibration Source Levels from Construction Equipment

Ground-borne vibration related to human annoyance is generally related to root mean square (rms) velocity levels expressed in VdB. However, a major concern with regard to construction vibration is damage to structures and utilities. Consequently, construction vibration is generally assessed in terms of peak particle velocity (PPV).

The relationship of PPV to rms velocity is expressed in terms of “crest factor”, defined as the ratio of the PPV amplitude to the rms amplitude. Peak particle velocity is typically a factor of 1.7 to 6 times greater than rms velocity.

Various types of construction equipment have been measured under a wide variety of construction activities with an average of source levels reported in terms of velocity as shown in Table 1 below. Table 1 was obtained from J.F. Wiss, “Vibrations During Construction Operations,” Journal of Construction Division, Proc. American Society of Civil Engineers, pp. 239 – 246, September 1974.

Section 01 57 50 Page 6

TABLE 1

Vibration Source Levels for Construction Equipment

Equipment PPV at 25 ft (in/sec) Approximate Lv* at 25 ft

Pile Driver (impact) upper range 1.518 112 Typical 0.644 104

Pile Driver (sonic) upper range 0.734 105 Typical 0.170 93

Clam shovel drop (slurry wall) 0.202 94

Hydromill (slurry wall) in soil 0.008 66 in rock 0.017 75

Vibratory Roller 0.210 94 Hoe Ram 0.089 87 Large bulldozer 0.089 87 Caisson drilling 0.089 87 Loaded trucks 0.076 86 Jackhammer 0.035 79 Small bulldozer 0.003 58

* RMS velocity in decibels (VdB) re 1 micro-inch/second

2.2 Damage Assessment

The following calculation is based on the use of a Pile Driver for estimating vibration impact at the upper range of pile driving activities.

PPVequip = PPVref x (25/D)1.5

Where: PPV (equip) is the peak particle velocity in in/sec of the equipment adjusted for distance.

PPV (ref) is the reference vibration level in in/sec at 25 feet from Table 1.

D is the distance from the equipment to the receiver.

Example: At 50-foot distance.

PPVequip = (1.518 in/sec) x (25/50)1.5

PPVequip = 0.537 in/sec at 50 feet from source.

2.3 Additional Considerations

Although Table 1 provides a typical and upper range level for pile driving equipment, it should be noted that there is a considerable variation in reported ground vibration levels from pile driving activities. The data provides a reasonable estimate for a wide range of soil conditions.

The damage assessment calculation is based on point sources with normal propagation conditions for typical pile driving. Propagation of the vibrations generated during pile driving activities will be subject to the on-site subsurface conditions with possible irregular propagation caused by the on-site soil constituents.

Section 01 57 50 Page 7

3.0 FIELD VERIFICATION

“Real-time” ground vibration measurements will be recorded during on-site pile driving activities. Frequency and amplitude transmission characteristics of the soil strata underlying the site will be investigated through seismic measurements. The measurements obtained will also be used to verify safe levels of pile driving activities based on peak particle velocity

(PPV).

Studies cited by the U.S. Bureau of Mines in their Report of Investigations 8485/1980, titled “Structure Response and Damage Produced by Vibration from Surface Mine Blasting.”

indicate that surrounding structures should not be subjected to prolonged ground vibrations at or above 0.5 in/sec. Based on the nature of the proposed construction activity and the anticipated PPV calculated in the damage assessment, we recommend a peak particle velocity limit of 1.0 in/sec for vibrations transmitted to existing PGW gas mains and other critical PGW gas facilities. This limit may be modified based on “real-time” measurements and/or proximity of pile driving activities to surrounding structures with lower vibration thresholds.

4.0 SEISMOGRAPH INSTRUMENTATION AND RECORDING MODES

During construction operations, velocity transducer seismographs will be used to continuously monitor and record vibrations. We recommend that the seismographs used be digital INSTANTEL® Series III seismographs or equivalent instrumentation. The contractor will provide and install the seismographs, and will monitor the pile driving operations.

Seismographs will be set to monitor in continuous histogram-combo mode to record the PPV and frequency over the entire period of construction activity. Each seismograph will be shake table calibrated by the manufacturer within the last year. All seismographs shall meet the following standard specifications:

• Range: 0 to 9 in/sec (seismic).

• Trigger Levels: 0.02 and 0.5 in/sec (maximum).

• Accuracy: 3% at 15 Hz.

• Acceleration, Velocity and Displacement: Calculated using entire waveform.

• Sampling Rate: Standard 1024 samples per second per channel.

• Record Modes: Manual and trigger with full waveform recording.

• Minimum Record Time: 1 to 10 seconds in 1 second increments, plus 0.5 seconds pre-trigger.

• Full Wave Events: Storage of a minimum of 90 events.

• Summary of Events: Storage of a minimum of 250 events.

• Printing: Equipment shall be capable of printing event results in the field.

• Operation Temperature Range: 0 to 122 F.

• Channel Inputs: Minimum of 4 channel inputs per unit.

5.0 MONITORING LOCATIONS AND PLACEMENT

Two (2) seismograph units shall be located either at the ground surface above the existing PGW gas main and other critical PGW gas facilities or secured directly to the existing PGW gas main and other critical PGW gas facilities, if exposed, nearest to the pile driving activities.

At least two (2) seismograph units shall be stationed, for monitoring vibration at all times.

The locations of the seismographs shall be adjusted based on the progress of pile driving activity to monitor vibrations within 100-foot of pile driving activities. (See attached Figure 1)

Section 01 57 50 Page 8

Upon review of the field seismograph data, the contractor shall modify the VMP as needed, and for implementation as construction progresses.

6.0 RECOMMENDATIONS AND CONCLUSIONS

6.1 Results of the damage assessment and implementation of the VMP must indicate that maximum sustained forces anticipated to arise from pile driving are below the maximum values that can be withstood by the existing PGW gas main and other critical PGW gas facilities.

6.2 A “not-to-exceed” sustained particle-velocity of 1.0 in/sec during construction activities is high enough to assure minimal restrictions to these activities, yet is conservative enough to be protective of the existing PGW gas main and other critical PGW gas facilities. This value will further be evaluated and modified as pile driving operations progress.

6.3 Should any gas lines be located within a 100-foot radius of the proposed pile locations, a preconstruction leak survey shall be performed to document the existing condition of the gas lines prior to the start of pile driving activities.

7.0 LIMITATIONS

7.1 This report has been prepared in accordance with generally accepted design practice for specific application to this project.

7.2 The recommended vibration limits put forth for the pile driving activities are recognized as established safe standards for vibration control and in no way relieve the Contractor from responsibility for damage to adjacent properties resulting from his construction activity even when these vibration thresholds are met. Soil analysis to determine the susceptibility of the soils to liquefaction and settlement will be evaluated on a project specific basis as required by PGW.

7.3 It is emphasized that compliance with this vibration monitoring plan does not warrant that vibration damage to any PGW gas mains and other critical PGW gas facilities being monitored will not occur even when readings indicate vibration levels are below normally accepted threshold values.

Section 01 57 50 Page 9

9fgy8845h: Amendment No. 0007

IFB W912BU-11-B-0009