In this paper, several hundred specimens were compacted and tested to evaluate the potential of beam testing protocols to directly measure four mechanical properties from one beam. Mechanical properties measured through beam testing protocols were compared to properties of Plastic Mold (PM) Device specimens and were found to be comparable once specimen densities were corrected. Mechanical properties were also used to quantify mechanical property relationships often used as pavement design inputs. When compared to traditionally recommended mechanical property relationships, relationships between elastic modulus and unconfined compressive strength as well as modulus of rupture and unconfined compressive strength were overly conservative; however, indirect tensile strength and unconfined compressive strength relationships from literature were accurate. This paper also assessed an elevated temperature curing protocol to simulate later life pavement mechanical properties on laboratory specimens. Mechanical properties of laboratory specimens that underwent accelerated curing were shown to be comparable to 10 to 54 year old cores taken from Mississippi highways.

A comprehensive laboratory testing program, field-testing program, numerical analysis, and life-cycle cost analysis were conducted to evaluate the beneficial effects of incorporating shrinkage-reducing admixture (SRA), polymeric microfibers (PMFs), and optimized aggregate gradation (OAG) into internally cured concrete (ICC) mixtures for rigid pavement applications. Results from the laboratory program indicate that all the ICC mixtures outperformed the standard concrete (SC) mixture. All the ICC mixtures showed a decrease in drying shrinkage compared to the SC mixture. Based on the laboratory program, three ICC mixtures and one SC mixture were selected for the full-scale test and subjected to a heavy vehicle simulator for accelerated fatigue testing. Extensive testing and analysis have shown that ICC mixtures incorporating SRA, PMFs, and OAG can be beneficially used in pavement applications to achieve increased pavement life.

Pervious concrete is a stormwater management practice used in the United States, Europe, China, Japan, and many other countries. Yet the design of pervious concrete mixtures to balance strength and permeability requires more research. Sphere packing models of pervious concrete were used in compressive strength testing simulations using the discrete element method with a cohesive contact law. First, three mixtures with varied water-cement ratios (w/c) and porosities were used for model development and validation. Next, an extensive database of simulated compressive strength and tested permeability was created, including 21 porosities at three w/c. Analysis of the database showed that for pavement applications where high permeability and strength are required, the advised porosity is 0.26 to 0.30, producing average strengths of 14.4, 11.1, and 7.7 MPa for w/c of 0.25, 0.30, and 0.35. The model can guide the mixture design to meet target performance metrics, save materials and maintenance costs, and extend the pavement life.

Beam specimens of polypropylene fiber-reinforced concrete (PPFRC) with 1.3 vol. % having three different sizes, 100 x 100 x 400 mm, 150 x 150 x 530 mm, and 200 x 200 x 650 mm, were tested under four-point bending tests to investigate the flexural behavior (flexural and post-cracking strengths). The beam specimens were quarried from PPFRC slabs to evaluate the influence of the fiber orientation and distribution and the concrete casting and loading directions on the flexural behavior. The test results show that the difference in the fabrication methods of specimens considerably affected the flexural behavior. The flexural cracking strength was accompanied by the size effect and the post-cracking strength, significantly decreased when compared with standardized prism specimens; however, the post-cracking strength was not sensitive to the size effect. Furthermore, the pavement thickness of PPFRC was compared with that of plain concrete with the calculation using the post-cracking strength.

Lack of understanding of the compaction mechanism, both in the laboratory and field, could result in significant underestimation or overestimation of the roller-compacted concrete pavement (RCCP) performance. The literature (1987 to 2022) depicts that there are numerous techniques to design RCCP in the laboratory; however, which method could closely simulate the field compaction is not fully explored. The present paper critically reviews the fundamental parameters affecting the strength characteristics of RCCP when compacted with different compaction mechanisms in the laboratory and attempts to rank the compaction methods based on the field performance. Also, recommendations are made on how to fabricate the specimens without having much impact on the considered compaction technique. The techniques that have been considered are the vibratory hammer, vibratory table, modified Proctor, gyratory compactor, and special compactors such as California kneading compactor, Marshall hammer, and duplex roller. Based on the present review, future research prospects are outlined to improve the performance of RCCP.