2400 33RD ST CRANE LOADING 2018-01-02 MF Import

Granite Construction Inc./Everett Station December 23, 2008 JA # 4670.8 o A 2" x 8' x 8' steel plate of a 12" x 8' x 20' timber mats can be provided by Granite Construction (Granite) to place under each outrigger to spread out the load from the crane. Evaluation Based on the information provided, we understand that the largest weight concentration on an outrigger will be 273,500 lbs. Using the minimum depth to the concrete casing, we evaluated the weight that the HS 20 live load would put on the top of the concrete casing. We estimate that the maximum weight of the HS 20 live load would be 35,000 Ibs, or 2,083 Ibs per foot of pipe. Using the Eloussinesq ecuation, we evaluated the pressure of the maximum outrigger weight on top of the concrete casing with the steel plate and the timber mats in plaG;. Based on the estimated load distribution of the steel plates, a factor of safety of 1.65 was calculated if the steel plates were used. By using the timber mats, the factor of safety was increased to over 3.5. Conclusion & Recommendation Based on these calculations, JA concludes that either type of load dissipation means should work theoretically. However, because of approximate nature of these calculations and the relatively loose/soft soil conditions present, we recommend using the timber mats under each outrigger because they appear to distribute the load more efficiently. JA also recommends that the mat's long axis be placed across the pipe line so that more load is transmitted around the outside of the pipe. Attachments: Appendix A: Loading Calculations Appendix 6: Reprint of American Concrete Pipe Association's Highway Live Loads on Concrete Pipe