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• 1 � , 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 andpressures 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 imtnediately 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 � of the Geotechnical Engineer or his or her representative. Approval of any and all onsite 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. j ( 5.0 GROUT NIIXTURE � 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 I wrth percent passmg 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 � operating pressures. I • Lime will be hydrated if utilized. � � • M�water shall be potable. ' • Once mixed,the cement/sand grout(including approved additives) sha11 obtain a minimwn 48-hour compressive strength of 200 psi. Grout Mig i The mixture used for grouting shall be a creamy consistency which will permit the grout to flow. If � requested,when samples of the grout mixture are set aside for at least 12 hours in a standard f concrete test mold,the resulting 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 I representative.The grout rnix 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 mixiure. � I 6.0 GROUT MIXING&PLACING � If on site mixing is used,facilities sha11 be provided for accurately measuring the ingredients i.n � each batch of grout. The ingredients shall be thoroughly mixed and immediately pwnped to the I grout pipes through a flexible hose not more than 250 feet long. , . �