Interfacial Shear Bond Strength between Steel H-Piles and Polymer Concrete Jackets

Abstract

Steel H-piles have been used widely in bridge construction throughout the U.S. because of their relatively large load-carrying capacity while occupying a small area. However, many H-piles suffer from corrosion, which may lead to abrupt collapse. A cost-effective repair technique, including encasing the corroded region of the steel pile into a concrete jacket, which acts as an alternative load path for the applied axial load, has been used by several state Departments of Transportation. Methyl methacrylate polymer concrete (MMA-PC) is a type of concrete that is commonly used as a repair material. However, there is limited research on the assessment of bond strength between MMA-PC and steel elements. This paper investigates experimentally the bond behavior of seven full-scale steel H-piles encased in concrete jackets. The jackets were cast using either MMA-PC or Portland cement concrete (CC). Different embedment lengths of 63.5 mm (2.5 in.), 127 mm (5 in.), and 190.5 mm (7.5 in.) were used for the MMA-PC and one embedment length of 254 mm (10 in.) was used for the CC jacket. Cylindrical and prismatic jacket configurations were used and tested using push-out. The experimental results revealed that using the MMA-PC jacket was more effective compared with the CC jacket in relation to the load-carrying capacity. For design purposes, a shear bond stress of 2.96 MPa [0.43 kips per square inch (ksi)] can be used for MMA-PC jackets having an embedment length of at least 127 mm (5 in.) whereas a value of 0.83 MPa (0.12 ksi) can be used for CC.

Mechanical Properties of High Early Strength Class C Fly Ash-Based Alkali Activated Concrete

“…This is a huge advantage for prefabricated structural elements which are emerging for accelerating infrastructure construction ( 8 , 9 ). Thermal curing can be adopted, also, for cast-in-place using thermal blankets or similar techniques ( 10 ). Classes F and C FA-based AAC were reported to be thermally cured at an elevated temperature ( 11 – 19 ).…”

Behavior of Ultrahigh-Performance Concrete Plates Encasing Steel H-Piles

“…This corrosion triggers section loss, which reduces the axial and bending capacity of the corroded steel H-pile, impairing the overall strength of the supporting structure (1)(2)(3). To address this challenge, repairing methods have been proposed, including attaching welded or bolted steel plates and cast-in-place concrete encasement with or without fiberreinforced polymer (FRP) jackets (4)(5)(6)(7). However, the addition of steel plates is inherently susceptible to corrosion, and the concrete encasement is challenging for field implementation, especially underwater, as it requires onsite casting and curing along with reinforcement, temporary support, and formwork.…”

Innovative Approach to Repair Corroded Steel Piles using Ultra-High Performance Concrete

“…Various methods such as concrete encasement (4), fiber-reinforced polymer (FRP) wrapped concrete encasement (5-7), and addition of welded or bolted steel plate (8) were used, by many departments of transportation in the U.S., to repair H-piles. However, these repair methods are challenging to implement and add heavyweight to the existing piles (9,10).…”