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i - � Dr.Michael Caselnova s Office 2 Geohazards Project No. 2008674 i December 9,2008 i 4.0 EQUIPMENT i Grout Injection Equipment ; A continuous flow,positive displacement model capable of pumping cement grout with a slump (ASTM C-143) of 3 to 6 inches maximum and pressures up to 600 psi (i.e., Schwing Model BPA ' 750D-15R or equivalent) shall be used. A pressure gauge shall be located in-line at the top of the � casing or immediately before the top of the casing. The gauge shall be capable of reading pressures ' up to 600 psi in increments of 25 psi or smaller. Alternate equipment may be used at the discretion j of the Geotechnical Engineer or his or her representanve. Approval of any and all onsite I equipment does not infer final acceptance. Injection Pipes ; Minimum inside diameter: 2 inches,Maximum inside diameter: 3 inches. Use of reducing nipples � is not allowed. � � i �� SA GROUT MIXTURE � � General � The materials used in this work shall conform to standard grouting practices as follows: � ! • Portland cement will conform to ASTM C-150. Aggregate will be natural sand material � with percent passing the No. 200 sieve not greater than 30 percent.No maximum grain size � is specified,however, it must not create sand blocking at the nozzle at the specified ; I � , operating pressures. � j • Lime will be hydrated if utilized. � i • Mix water shall be potable. j i • Once mixed,the cement/sand grout(including approved additives) shall obtain a minimum � 48-hour compressive strength of 200 psi. � � � Grout Mix � , The mixture used for grouting shall be a creamy consistency which will permit the grout to flow. If I I requested,when samples of the grout mixture are set aside for at least 12 hours in a standard concrete test mold,the resulting fiee surface water height shall be less than one percent of the i initial sample height. Slump shall not exceed 6 inches. However,the slump may be varied � �� throughout the grouting operation at the discrerion of the Geotechnical Engineer or his or her representative. The grout mix sha11 not contain more than 0.6%by weight(221bs/cy) of bentonite. I If bentonite is to be used, it must be hydrated prior to the addition of cement to minimize bleeding � and segregation. The use of bentonite in compaction grouting can cause a loss of compressive i strength of the grout mixture. ; , 6A GROUT MIXING&PLACING I If on site mixing is used, facilities shall be provided for accurately measuring the ingredients in � each batch of grout. The ingredients shall be thoroughly mixed and immediately pumped to the � 'I grout pipes through a flexible hose not more than 250 feet long. � i � � � I