Long-Term Performance of Jointed Plain Concrete Pavement with Rapid Strength Concrete On California Highways

Rapid Strength Concrete (RSC) slabs on six California jointed plain concrete pavement (JPCP) highway projects were surveyed. These projects had been previously surveyed in 2008 at 3-years of age and by 2018 had reached a service life of 13-years. Of the initial 5430 slabs examined in 2008, a total of 1493 RSC slabs, located on 12 traffic lanes, were observed and distress types recorded again in 2018. These slabs included both CTS and 4x4 RSC located in both inner and outer lanes. Only a small percentage (1.4%) of the 5,430 RSC slabs exhibited any distress in 2008 after 3-years' service and the increases were small over the next 10 years of service with the exception of transverse fatigue cracks. The transverse (top down fatigue) type of cracking had the highest percentage and largest increase of any distress type. The heavy truck outside lanes exhibited 21% transversely cracked RSC slabs and the inner passing lanes 3%. The outer truck lanes carried over 3 times more trucks than inner lanes. The RSC slabs were mostly 200-223 mm thick and thus susceptible to fatigue damage. The overall performance of the RSC slabs (both CTS and 4x4 RSC materials) were similar and considered to be outstanding over 13 years with a large majority expected to survive many more years.

Delay Factor Analysis for Indian HAM Highway Construction Projects

Government has approved the hybrid annuity model (HAM) for building National Highways (NH) to speed up the construction of roads in the country by renewing interest of private developers in highway projects. 40% the Project Cost is to be provided by the Government as Construction Support during the construction period and the balance 60% as annuity payments over the operations period along with interest thereon to the concessionaire. Execution of hybrid annuity model (HAM) projects, which is the preferred mode of awarding by the National Highways Authority of India (NHAI), is largely on schedule with about 60% of projects, covering 3,200 km of roads, completed on time. The rest of the projects, however, are delayed largely due to various reasons. In order to identify and analysis of delay causes in highway projects of HAM model, this study provides a questionnaire survey-based study. Land acquisition delay is found as the most severe delay cause of highway projects of HAM model. Waste of time in controlling the traffic is found as the least severe delay cause of highway projects of HAM model. The study is supposed as useful to HAM construction managers for delay analysis of highway projects. Keywords: Hybrid annuity model, Highway projects, Delay analysis, Questionnaire survey.

The Effect of “Federal -Aid Swap” Programs and Davis-Bacon Prevailing Wages on Highway Construction Costs and Contractor Composition: Evidence From Iowa

“Federal-aid swap” programs allow states and local governments to bypass federal Davis-Bacon prevailing wages and Disadvantaged Business Enterprise (DBE) goals by exchanging federal funds that have been allocated to highway projects with state funds. The Iowa Department of Transportation approved a federal-aid swap program in February 2018. Using data on more than 1,200 highway construction projects in Iowa from 2016 to 2020, I find that the cost of projects in the federal-aid swap program are not statistically different from those that were not swapped, after accounting for project size and complexity, project type, and project location. Regression results indicate that Davis-Bacon prevailing wages and DBE goals have no effect on total construction costs. However, the federal-aid swap program is statistically associated with a decrease in the likelihoods that a project is covered by the Davis-Bacon Act by 10 percentage points and DBE goals by 4 percentage points. Because the payment of Davis-Bacon prevailing wages is statistically associated with an 8 percentage-point decrease in the chances that a highway project is awarded to an out-of-state contractor, the federal-aid swap program may have increased the market share of out-of-state contractors at the expense of Iowa-based contractors.