PDFWAC 296-155-688

Vertical slip forms.

(1) Slip forms must be designed and constructed, and the form movement carried out, under the immediate supervision of a person or persons experienced in slip form design and operation. Drawings prepared by a qualified engineer, showing the jack layout, formwork, working decks, and scaffolding, must be available at the job site, and followed.
(2) The steel rods or pipe on which the jacks climb or by which the forms are lifted must be designed for this purpose. Such rods must be adequately braced where not encased in concrete.
(3) Forms must be designed to prevent excessive distortion of the structure during the jacking operation.
(4) Vertical slip forms must be provided with scaffolding or work platforms completely encircling the area of placement.
(5) Jacks and vertical supports must be positioned in such a manner that the loads do not exceed the rated capacity of the jacks.
(6) The jacks or other lifting devices must be provided with mechanical dogs or other automatic holding devices to support the slip forms whenever failure of the power supply or lifting mechanism occurs.
(7) The form structure must be maintained within all design tolerances specified for plumbness during the jacking operation.
(8) Lifting must proceed steadily and uniformly and must not exceed the predetermined safe rate of lift. A jacking system, which provides precise, simultaneous movement of the entire form in small preselected increments, is recommended for large structures.
(9) Workers placing reinforcing steel must comply with the requirements of chapter 296-880 WAC when working above the scaffold level.
(10) The total allowable load on slip form platforms must be determined by the design engineer and enforced by the field supervisor.
(11) Lateral and diagonal bracing of the forms must be provided to prevent excessive distortion of the structure during the sliding operation.
(12) While the slide is in operation, the form structure must be maintained in line and plumb.
(13) A field supervisor experienced in slip form construction must be present on the deck at all times.
[Statutory Authority: RCW 49.17.010, 49.17.040, 49.17.050, and 49.17.060. WSR 22-15-089, § 296-155-688, filed 7/19/22, effective 8/19/22; WSR 16-09-085, § 296-155-688, filed 4/19/16, effective 5/20/16; WSR 98-05-046, § 296-155-688, filed 2/13/98, effective 4/15/98. Statutory Authority: Chapter 49.17 RCW. WSR 91-03-044 (Order 90-18), § 296-155-688, filed 1/10/91, effective 2/12/91; WSR 89-11-035 (Order 89-03), § 296-155-688, filed 5/15/89, effective 6/30/89.]