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� I • I � Dr.Michael Caselnova's Office 2 Geohazards Project No. 2008674 � December 9,2008 ! s 4.0 EQUIPMENT � Grout Injection Equipment I 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 Mode1 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 representative. Approval of any and all onsite I equipment does not infer final acceptance. j I Injection Pipes � Minimum inside diameter: 2 inches,Maximum inside diameter: 3 inches.Use of reducing nipples is not allowed. 5.0 GROUT MIXTURE � '� General I I' The materials used in this work shall conform to standard grouting practices as follows: � � • Portland cement wi11 conform to ASTM G150. Aggregate will be natural sand material ' I with percent passing the No. 200 sieve not greater than 30 percent.No maximum grain size , I is specified,however,it must not create sand blocking at the nozzle at the specified i operating pressures. � � Lime will be hydrated if utilized. i • Mix water shall be potable. � • Once mixed,the cement/sand grout(including approved additives) shall obtain a minimum 48-hour compressive strength of 200 psi. Grout Mix � The m�ture used for grouting shall be a creamy consistency which will permit the grout to flow. If ' I requested,when samples of the grout mixture are set aside for at least 12 hours in a standaxd � concrete test mold,the resultmg free surface water height shall be less than one percent of the � initial sample height. Slump shall not exceed 6 inches. However,the slump may be varied � throughout the grouting operation at the discretion of the Geotechnical Engineer or his or her representative.The grout mix shall 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 � � strength of the grout mixture. ; 6.0 GROUT NIIXING&PLACING ' If on site mixing is used, facilities sha11 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. ; �