Search Results (2)

To address concrete cracking in submerged box-shaped hollow thin-walled piers under static ice and hydrostatic pressure, this study proposes a composite strengthening method employing externally bonded steel plates coupled with concrete infill blocks. Based on mechanical theoretical derivation, the strengthened structure is simplified as a cooperative system comprising compression–truss and suspended-cable mechanisms. Key design parameters—including steel plate span, thickness, infill block height, and plate corner configuration—are optimized using a genetic algorithm. The optimization objective minimizes strengthening cost, subject to constraints of concrete crack resistance, steel plate strength, and deformation control, ultimately determining the numerically optimal composite strengthening solution. Validation through planar finite element models demonstrates that: (1) the proposed system effectively suppresses cracking in the original structure; (2) peak stresses in the steel plates remain below the yield strength of Q345 steel; and (3) the theoretical design is reasonable and effective, which can solve the cracking problem of the wading-tank hollow thin-walled pier under the action of surrounding load. Full article

The production and servicing of cement-based building materials is a source of large amounts of carbon dioxide emissions globally. One of the ways to reduce its negative impact, is to reduce concrete consumption per cubic meter of building structure through the introduction of hollow concrete products. At the same time, to maintain the load-bearing capacity of the building structure, it is necessary to significantly increase the strength of the concrete used. However, an increase in strength should be achieved not by increasing cement consumption, but by increasing the efficiency of its use. This research is focused on the development of technology for the production of thin-walled hollow concrete blocks based on high-strength, self-compacting, dispersed, micro-reinforced, fine-grained concrete. The use of this concrete provides 2–2.5 times higher strength in the amount of Portland cement consumed in comparison with ordinary concrete. The formation of external contours and partitions of thin-walled hollow blocks is ensured through the use of disposable formwork or cores used as void formers obtained by FDM 3D printing. This design solution makes it possible to obtain products based on high-strength concrete with higher structural and thermal insulation properties compared to now existing lightweight concrete-based blocks. Another area of application of this technology could be the production of wall structures of free configuration and cross-section due to their division, at the digital modeling stage, into individual element-blocks, manufactured in a factory environment. Full article