Mitigating Transverse Joint Faulting in Jointed Concrete Pavement with Polyurethane Foam

Abstract

A case study was conducted to assess the effectiveness of reducing transverse faulting on jointed concrete pavement with polyurethane foam (PF) on a principal arterial roadway with an average daily traffic of 15,800 with 20% trucks. The PF fault correction process entailed reducing faults to approximately 0.25 in. by saw-cutting the full depth through the joints and lifting the slabs with PF. A sampling plan was established: the entire project was measured for faulting and roughness by a high-speed profiler before and after the PF fault correction process. Three test sections with 10 slabs each were assessed with a falling weight deflectometer, ARRB walking profiler, and manual fault measurements. Seventeen cores were taken at various locations to obtain in-place PF samples. Statistical hypothesis testing was conducted to compare the before-and-after treatment effect of the PF process. Approximately 18% improvement in ride quality and 79% improvement in fault reduction were realized by the PF fault correction process. Unfortunately, the PF process severely affected load transfer efficiency, with a 43% increase in joints having poor load transfer and a 27% increase in joints needing load transfer improvement. It is reasonable to assume that these problems were caused primarily by saw-cutting through the joints and not by PF itself. Void potentials were increased slightly (8%) by the process.

Assessing Seasonal Performance, Stiffness, and Support Conditions of Pavement Foundations

“…Recent studies have reported field performance results on HDP foam stabilized concrete pavements with mixed conclusions in terms of the observed improvements (Chen and Scullion 2007;Chen et al 2009;Chen et al 2008;Crawley et al 1996;Gaspard and Morvant 2004;Gaspard and Zhang 2010;Opland and Barnhart 1995;Vennapusa and White 2014). Opland and Barnhart (1995) found that ride quality, LTE at joints and cracks, and peak deflections under FWD loads were improved shortly after stabilization, particulary in sites with previous severe cracks.…”

“…They also found that the injection process produced new voids under the panels, but re-injection mitigated the problem. Gaspart and Morvant (2004) and Gaspard and Zhang (2010) reported FWD and ride quality tests on continuously reinforced PCC and jointed PCC pavements, before and after injecting HDP foam for filling slab voids and leveling slabs. Their results indicated that foam injection successfully filled voids beneath the pavements, but did not improve ride quality.…”

“…The material had a reaction time of < 1 min and a curing time of < 15 min. Reaction time refers to the time to react and cause the material to expand, while curing time refers to the time for the foam to achieve its ultimate density and strength (Gaspard and Zhang, 2010).…”

“…Out of the 7 state agency specifications reviewed, only 2 agencies currently allow HDP foam for slab stabilization, but all 7 allow HDP foam for slab jacking applications. The foam injection method has been gaining popularity for slab stabilization applications because of its advantages with faster setting times and strength gains compared to cementitious grouts (Abu al-Eis and LaBarca 2007; Barron 2004;Chen et al 2008;Gaspard and Zhang 2010). When cementitious grouts are used, the traffic delay times typically vary from several hours to three days depending on how fast the grout achieves its strength (Table 6.1).…”

“…Cementitious grout is the most common material used for slab stabilization(ACPA 1994). The use of injected expanding polyurethane foam is increasingly being used as an alternative to grout, primarily because of the shortened construction time, reduced materials/equipment requirements, and less labor (Abu al-Eis and LaBarca 2007,Barron 2004, Chen et al 2008, Gaspard and Zhang 2010). Currently, a few state agencies (Missouri and New Jersey) have included high density polyurethane (HDP) foam technology as part of their standard specifications for slab stabilization(MoDOT 2009b; NJDOT 2007a).…”