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9-36 Shaft-Related Materials9-36 Shaft-Related Materials
9-36.1 Shaft Casing
9-36.1(1) Permanent Casing
Permanent casing shall be of steel base metal conforming to ASTM A36, ASTM A252 Grades 2 or 3, ASTM A572, or ASTM A588. Permanent casing for CFST shafts shall conform to Section 9-10.5 requirements for steel pipe piling.
9-36.1(2) Temporary Casing
Temporary casing shall be a smooth wall structure of steel base metal, except where corrugated metal pipe is shown in the Plans as an acceptable alternative material. Use of corrugated metal pipe as temporary casing will not be allowed for shaft foundations of monotube sign bridges and cantilever sign structures.
9-36.2 Shaft Slurry
9-36.2(1) Mineral Slurry
Mineral slurry shall conform to the following requirements: Property Test Requirement Density (pcf) Mud Weight (Density) API 13B-1, Section 1 63 to 75 Viscosity (seconds/quart) Marsh Funnel and Cup API 13b-1, Section 2.226 to 50 PH Glass Electrode, pH Meter, or pH Paper 8 to 11 Sand Content (percent) Sand API 13B-1, Section 5 Prior to final cleaning 4.0 max. Immediately prior to placing concrete4.0 max. Use of mineral slurry in salt water installations will not be allowed. Slurry temperature shall be at least 40F when tested.
9-36.2(2) Synthetic Slurry
Synthetic slurries shall be used in conformance with the manufacturer’s recommendations and shall conform to the quality control plan specified in Section 6-19.3(2)B, item 4. The synthetic slurry shall conform to the following requirements: Property Test Requirement Density (pcf) Mud Weight (Density) API 13B-1, Section 1 64 max. Viscosity (seconds/quart) Marsh Funnel and Cup API 13b-1, Section 2.232 to 135 PH Glass Electrode, pH Meter, or pH Paper 6 to 11.5 Sand Content (percent) Sand API 13B-1, Section 5 prior to final cleaning 1.0 max. immediately prior to placing concrete1.0 max. M 41-10 Page 9-239 Shaft-Related Materials 9-36If the product is not listed on the Qualified Products List, the Contractor shall submit a Request for Approval of Materials Source (RAM) form with the following information: • Test data showing conformance to the properties in the table above, and • Documentation showing that the synthetic slurry (with load-tested additives) has been approved by the California Department of Transportation (Caltrans).
9-36.2(3) Water Slurry
Water without site soils may be used as slurry when casing is used for the entire length of the drilled hole. Water slurry without full length casing may only be used with the approval of the Engineer. Water slurry shall conform to the following requirements: Property Test Requirement Density (pcf) Mud Weight (Density) API 13B-1, Section 1 65 max. Sand Content (percent) Sand API 13B-1, Section 5 1.0 max. Use of water slurry in salt water installations will not be allowed. Slurry temperature shall be at least 40ºF when tested.
9-36.3 Steel Reinforcing Bar Centralizers
Steel reinforcing bar centralizers shall be steel, conforming to the details shown in the Plans. The Contractor may propose the use of alternative steel reinforcing bar devices as part of the shaft installation narrative as specified in Section 6-19.3(2)B, item 9, subject to the Engineer’s review and approval of such devices.
9-36.4 Access Tubes and Caps
Access tubes for CSL or TIP testing shall be steel pipe of 0.145 inches minimum wall thickness and at least 1½ inch inside diameter. The access tubes shall have a round, regular inside diameter free of defects and obstructions, including all pipe joints, in order to permit the free, unobstructed passage of 1.3-inch maximum diameter source and receiver probes used for the crosshole sonic log tests. The access tubes shall be watertight and free from corrosion, with clean internal and external faces to ensure a good bond between the concrete and the access tubes. The access tubes shall be fitted with watertight threaded PVC caps on the bottom, and shall be fitted with watertight PVC caps, secured in position by means as approved by the Engineer, on the top.
9-36.5 Grout for Access Tubes
Grout for filling the access tubes at the completion of the crosshole sonic log tests shall be a homogeneous mixture of neat cement grout and potable water, conforming to Section