How To Use Glass Cullet In Construction Projects

Transcription

1 Case History Use of Glass Aggregate in Construction Projects Project Highlights Background Use of this material was proposed by representatives of the general contractor, W.G. Clark Construction Company. Location/Date MacMillan-Piper Transloading Facility, 1509 Taylor Way, Tacoma, Spring-Summer, Owner MacMillan-Piper. Material Used and Recycled Content 100% mixed color glass cullet. Material Source Waste Management of Seattle, Marilyn Skerbeck, (206) Quantity and Gradation 12,600 tons of 3/4-inch minus glass cullet. Cost The cullet was free to take from the Waste Management s Seattle Plant. Cost Savings The cost to ship the cullet from Seattle to Tacoma was comparable to the combined cost of buying and shipping natural soil fill from a local supplier. As a result, the overall saving on materials cost were minimal. There were no difference in long-term maintenance costs. Placement Placement procedures were similar to those for sand and gravel. General Contractor W.G. Clark Construction Co., Bill Swanson, (206) MacMillan-Piper Tacoma Transloading Project The project involved the construction of a 106,000 square-foot warehouse. Glass cullet was used to supplement imported natural aggregate as the subbase fill material beneath the warehouse and adjacent trailer dock slabs-on-grade. Material Specifications The gradation specification for the subbase fill material used beneath the truck and trailer dock slabs-on-grade was 3/4-inch minus. This fill was to be compacted to at least 95 percent of its maximum dry density as determined by a modified proctor test (ASTM D-1557). Safety Measures Site personnel were informed that gloves, heavy boots, and eye protection should be worn when working with the cullet, and that direct skin contact should be avoided. Construction Methods During construction, the subgrades for the warehouse and trailer dock slabs-on-grade were over-excavated about 5 feet below ground surface. This overexcavation was backfilled with alternating lifts of imported sand and gravel, and crushed glass cullet. The cullet was alternated with sand and gravel fill because it could not withstand prolonged truck or machine traffic without the formation of deep ruts. Both the sand and gravel and the cullet were placed in 8 to 12-inch thick loose lifts, which were compacted with a riding double-drum, vibratory roller compactor. No difficulty was experienced in meeting the compaction requirements of the cullet.

2 Lessons Learned Advantages Representatives of W.G. Clark found that the cullet was moisture insensitive, which allowed compaction of the cullet to continue during periods of wet weather. Problems The contractor found that truck or machine traffic over exposed cullet subgrades resulted in deep ruts. This problem was remedied in part by alternating each lift of cullet with a lift of sand and gravel. As-Built Status The cullet performed as well as natural aggregate in this application. At the time of this case study (four years following construction), the slabs show no visible signs of settlement. Issue Date: December 1997 Prepared by the CWC. CWC is the Managing Partner of the Recycling Technology Assistance Partnership (ReTAP). ReTAP is an affiliate of the national Manufacturing Extension Partnership (MEP), a program of the U.S. Commerce Department s National Institute of Standards and Technology (NIST). For more information on glass recycling or other assistance available at CWC, call (206) , at info@cwc.org, or visit our website at NIST MEP Environmental Program

3 MacMillian-Piper Transloading Project 1509 Taylor Way, Tacoma, Washington Spring-Summer ,600 tons of cullet used as structural fill under building slabs -on-grade Slide view of cullet placed as structural fill beneath slab, capped with 12 inches of sand and gravel

4 South corner of warehouse -- no signs of subgrade settlement Trailer dock -- no signs of subgrade settlement

5 West side of warehouse -- no signs of subgrade settlement Trailer loading dock interior -- no signs of subgrade settlement