Experimental Investigation on the Application of Ultra-Rapid-Hardening Mortar for Rigid Small Element Pavement

Abstract

Natural stones have been typically used as a paving material in historically conserved areas due to architectural aesthetic aspect and environmental impact. However, they have been traditionally suggested in light traffic volume due to the defects caused by the increased traffic loading and volume. The failures can lead to diverse problems such as losing flatness, severe damage to both vehicles and pedestrians, high traffic congestion, maintenance cost, etc. In order to overcome these obstacles, ultra-rapid-hardening (URH) cement for rigid small element pavement (SEP) was implemented as both jointing and laying course materials. Additionally, their mechanical properties were investigated according to BS 7533-4 and National Stone Surface (NSS) in the UK. Preliminarily, the proper mix mortar design was found by comparing design parameters. The compressive and flexural strength of the joint and laying course by age was verified, and the results in early-age stage were satisfied with the requirements. The adhesive and shear strengths depending upon the width of the joint were determined, and from the test outcomes, the optimal thickness of the joint was found as 15 mm. Furthermore, by contrasting the compressive strength of the laying course with the punching shear strength, the shear strength regarding joint states was increased by up to 134.3% (fully restrained), 127.9% (semirestrained), and 107.2% (non restrained). This investigation would be possible to use as baseline data for an evaluation of the long-term performance of rigid SEP.

Evaluation of Long-Term Performance for Bonded Natural Stone Pavement Using Accelerated Pavement Test [Part Ⅱ: Skid Resistance, Response of Deflection and FEM Analysis]

“…The mortar for joint filling and bedding course was a mixture of Ultra-Rapid-Hardening (URH) cement and retardant. The mix design was experimentally discovered and the mechanical properties were also examined in the former study [3]. The mortar showed improved performance with a comparison of minimum requirements from both BS 7533-4 and Natural Stone Surface (NSS) in the UK.…”

“…Furthermore, the test results showed a higher value compared to the related specifications. Similar to the mortar, the natural stones for the surface layer were also tested by following the KS F 2530 in the previous study [3]. The compressive strength and water absorption of the stone elements were investigated by KS F 2519 and 2518, respectively, and both properties have met the recommendation.…”

“…Block pavements constructed of natural stones are often required the specific areas where are in low traffic volumes such as communal sites, sidewalks, and historically neighbourhood areas [1][2][3]. Commonly, stone-paved roads are quarried in heritage sites or cities due to their variety in creation (patterns, texture, and environmental aspects) [1,[4][5][6][7][8][9].…”

Development of Bonded Natural Stone Pavement Using Ultra-Rapid-Hardening Mortar

“…URH cement is typically applicable to numerous construction applications such as grouting, shoe installations, and quick concrete repairs. The mix design of mortar was discovered in an earlier investigation that evaluated mechanical properties [3]. The compressive strength and flexural strength of mortar for laying course and joint filling are tabulated in Table 4.…”

“…Natural stones have generally been introduced as pavers for specific areas with low traffic volumes such as car parks, sidewalks, and historically preserved sites [1][2][3]. In particular, stone pavements are frequently required in historic areas or cities because of their architectural beauty and environmental aspects [1,[4][5][6].…”