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56 SPECIFICATIONS FOR SUBSURFACE EROSION STABILIZATION BY COMPACTION GROUTING SEPTA Frankford Transportation Building Philadelphia, PA PART 1 GENERAL 1.01 INTENT The intent of the compaction grouting specified herein is to provide soil densification within the limits shown on Sketch LP-1, dated March 6, STANDARDS AND REFERENCES A. The most recent version of the following testing methods or standards shall be employed: 1.03 DEFINITIONS 1. ASTM C150 Compliance Standard for Portland Cement 2. ASTM C143 Test Method for Slump of Portland Cement Concrete A. Compaction grout: A material blend of cement, fine aggregate, fines and water to achieve a pumpable, thixotropic, viscous grout of a low slump to enable pumping at high pressure and remain intact after injection. Material components can include sand, silt, clay, cement, ground slag, flyash, water and other admixtures. Strength of grout is intended only to be greater than existing strengthened soil conditions. B. Professional: The geotechnical engineering firm (Pennoni Associates, Inc.) retained by the Owner to perform Quality Assurance and Quality Control for the compaction grouting procedures outlined in this specification. C. Field Quality Control Representative (FQCR): The field representative of the Professional given specific monitoring tasks identified in this specification. The individual shall be under the direction of a Geotechnical Engineer registered in the Commonwealth of Pennsylvania SCOPE OF WORK A. The work shall consist of installation and monitoring of compaction grouting at the locations presented on Drawing, LP-1 provided under separate cover. B. In connection with the compaction grouting program the grouting contractor shall provide all labor, materials and equipment to accomplish the following items of work: 1. Implement ground movement monitoring system 2. Install grout pipes into dense soils, or to a maximum depth of 35 ft below existing grades and remove grout pipes 3. Furnish and inject grout 4. Monitor surface ground movements during compaction grouting operations 5. Follow compaction grouting sequence of operations March 6, 2015 SEPTA Frankford Transportation Building SEPTA Philadelphia, PA

57 C. It shall be the grouting contractor s responsibility to determine and implement the systems and criteria to ensure that specified improvement is achieved. PART 2 EQUIPMENT AND MATERIALS 2.01 GROUTING EQUIPMENT A. The grouting contractor shall supply proper means of advancing the grout pipe through the overburden soils, and other natural and/or man-made obstructions into the dense soils indicated on the boring logs at depths that vary from 8.5 to 25 ft below the existing grades. B. The grouting contractor shall supply all equipment required to operate a compaction grouting system capable of supplying the specified grout at variable flow rates and pressures, measured at the pump, up to 700 psi and at rates of 0.5 to 3 cubic feet per minute, as required to suit the application. C. The mixer shall be a continuous auger type to ensure complete uniform mixing of the materials used and shall be of sufficient capacity to continuously provide the pumping unit with mixed grout at its normal pumping range. The mixer must be capable of volumetrically proportioning the grout materials. Ready mixed grout is also acceptable with an approved mix design. D. The grouting contractor shall provide gauges or other instrumentation (measuring devices) to measure: 1. Continuous grout pressure close to the top of the injection casing 2. Flow rate of grout 3. Volume of grout injected (pump calibration) 4. Pump Stroke Counter E. The grouting contractor shall supply and implement monitoring equipment in accordance with Section 3.03 of these specifications. F. An adequate communication system shall be maintained between the pumping and batching plant and the injection location. As an alternate, the contractor may furnish a remote control system to allow full control (start, stop, flow rate, reversing) of the pump directly by the grouting technician from the injection point GROUT PIPES A. Grout pipes and connections shall be steel casing of adequate strength to maintain the hole and to withstand the required jacking and pumping pressures. The pipes shall be at least 2.0 in. inside diameter in order to adequately handle the specified low slump material without plugging. All casing shall be flush joint threaded to provide a smooth inner wall and unobstructed inside diameter. It shall be the contractor s responsibility to install casing that does not detrimentally impact the grouting procedure. B. Pipes shall be installed such that grout material will not travel in the annular space between the pipe and adjacent ground and escape at the surface when pumped. March 6, 2015 SEPTA Frankford Transportation Building SEPTA Philadelphia, PA

58 2.03 GROUT MATERIALS A. Portland Cement (ASTM C150) B. Fine aggregate shall be sand with a fines content (percent passing No. 200 sieve) of not less than 10 percent and not more than 30 percent. Natural fines may be supplemented with flyash, a minimal amount of bentonite, or aggregate washings. C. Proportions of the mixture shall be as required to achieve a pumpable mix with not more than a 2 inch slump unless otherwise approved by the Geotechnical Engineer. D. Upon discharge into the pump hopper or holding tank, the grout must be continuously agitated. Mixed grout may not be held in the agitator for more than 1.5 hours unless a set retarder, approved by the Professional, is used. PART 3 EXECUTION 3.01 SITE EXAMINATION A. Prior to submitting a bid price for the compaction grouting, the grouting contractor shall conduct a site inspection COMPACTION GROUTING A. Prior to the grouting, the pump shall be calibrated by means of counting the amount of strokes to fill a 55 gallon drum, or by alternate methods as approved by the Professional. B. Compaction grouting shall be performed in accordance with the grout injection point layout scheme as presented on Drawing, LP-1, or as directed by the Professional. Any secondary grout injection points indicated on the drawing or deemed necessary by geotechnical engineer will be performed following the completion of all primary grout locations and at the discretion of the Professional. C. The contractor shall predrill each grouting injection location using an air percussion drill rig, or similar. Predrilled holes shall terminate after 5 continuous feet of rock is encountered, or advanced to a maximum depth of 35 ft below existing grades. The contractor shall advance the grout pipe into the predrilled hole to depths that vary from 8.5 to 25 ft below existing elevations. D. Compaction grouting shall be performed from the bottom up beginning at least one stage above rock, if encountered, or beginning at the seating depth of the pipe, if no rock is encountered. E. The grout shall be injected at a stage depth until one of the following occurs, or as directed by the Professional: 1. Grout flow ceases at a pressure reading of 300 psi 2. Surface ground heave of in. or more is observed 3. An injected grout volume equal to 1.5 cy per 2 ft stage has been injected March 6, 2015 SEPTA Frankford Transportation Building SEPTA Philadelphia, PA

59 into the zone 4. Grout exits around the casing 5. Grout pressure causes the casing to rise out of the hole F. Compaction grouting shall be sequenced so that grouting does not take place within 7 ft of locations grouted within the previous 12 hours, unless authorized by the Professional. G. As compaction grouting is completed at each location, the grouting contractor shall completely fill the grout hole to the ground surface. Where grouting is performed through existing concrete slab, the existing slab shall be patched with a non-shrink grout to its original condition FIELD QUALITY CONTROL A. All compaction grouting shall be performed under the full-time observation of the FQCR. Grouting performed in the FQCR s absence shall not be accepted for payment. B. Layout of grout injection points shall be by the grouting contractor and checked by the FQCR. C. As detailed in Section 1.05C, daily records shall be maintained by the grouting contractor and submitted to the FQCR. D. The grouting contractor shall monitor surface movement as follows: 3.04 RESTRICTIONS 1. a level control system shall be implemented by the contractor 2. monitoring shall be carried out on a continuous basis whenever compaction grouting is occurring A. The Owner or grouting contractor shall be responsible for obtaining any State and municipal permits (if required) and conforming to all State and local regulations. PART 4 PAYMENT 4.01 METHOD OF PAYMENT A. Drilling and installation of approximately 225 lin. ft of grout casings required under the grout injection point layout scheme, and any required secondary grouting within the limits indicated as requiring compaction grouting, shall be a unit cost per linear foot of grout pipe. B. Injected grout shall be at a unit cost per cubic yard. C. Mobilization and demobilization shall be a separate lump sum item. March 6, 2015 SEPTA Frankford Transportation Building SEPTA Philadelphia, PA