Currently, low heat Portland (LHP) cement is widely used in mass concrete structures. The magnesia expansion agent (MgO) can be adopted to reduce the shrinkage of conventional cement-based materials, but very few studies found that investigate influence MgO on properties LHP materials. In this study, influences two types hydration, as well behavior were studied via pore structural and fractal analysis. results indicate: (1) addition reactive (with a reactivity 50 s shortened M50 thereafter)...

The corrosion of alkaline concrete materials exposed to a sulfuric acid environment is becoming more and prevalent, its damage assessment imperative. This study aims describe the corroded surfaces with different strength grades (C30, C50, C80) in environments terms their three-dimensional fractal dimension. Three kinds varying grades, namely C30, C80, were immersed solution pH ≈ 0.85 for four distinct durations, specifically 0, 28, 56, 165 days, accelerated tests. 3D laser scanning technique...

Engineering cementitious composites (ECC) is an innovative high performance engineering structural material with ductility, toughness, and unique multiple cracking characteristics. Currently, most of the fibers used in ECC are expensive Kuraray PVA produced Japan. More more researchers using Polyethylene (PE) made China low cost, strength elastic modulus to replace fibers. However, finer diameter hydrophobicity make it difficult for PE be distributed matrix evenly. In addition, research...

The challenging wind conditions surrounding power transmission lines exacerbate the wear and corrosion of line fittings. Thermal diffusion galvanizing technology, a novel method for obtaining layers, significantly enhances resistance metal components, thereby extending their service life. Holding temperature plays critical role in determining performance thermally diffused zinc coating. In this study, we prepared coatings containing rare earth oxides on 35CrMo steel at various holding...

Through direct shear tests, this paper aimed to research the effect of fine marble aggregate on strength and fractal dimension interface between soil concrete corroded by sulfuric acid. More realistic rough surfaces than artificially roughened were formed immersing four plates in plastic buckets filled with acid for different periods time. The sand was adopted imitate soil. 3D laser scanner employed obtain digital shapes subjected acid, evaluated dimension. Large experiments performed curves...

Due to the extraordinary mechanical properties of ultra-high-performance concrete (UHPC), shear stirrups in UHPC beams could potentially be eliminated. This study aimed determine effect beam height and steel fiber volume content on behavior non-stirrup under a larger span–depth ratio (up 2.8). Eight were designed fabricated including six two comparing stirrup-reinforced normal (NC) beams. The experimental results demonstrated that crucial factor affecting ductility, cracking strength,...

A partial-depth, diamond-shaped, ultra-high performance concrete (UHPC) connection with embedded transverse reinforcement between adjacent precast prestressed voided beams (APPCVBs) has been developed by the Federal Highway Administration (FHWA) to overcome disadvantages of longitudinal cracks within connections. In this study, shear behavior 14 spliced panel specimens FHWA UHPC will be experimentally investigated. One monolithic specimen tested as a reference. The test parameters include...

Abstract Ilmenite (FeTiO3) with a mean particle size of 30 – 45 um was first introduced into the oil industry as weighting material in 1976. However, its use limited mainly because abrasiveness to drilling equipment. Recently, superfine ilmenite (5 μm) address shortcomings traditional materials. The objective this study is discuss performance oil-based fluids using for HPHT applications. Oil-based density 1.92 SG containing API standard barite and were compared. filtration tests under static...

As a novel civil engineering material, Engineered Cementitious Composite (ECC) has attracted more and attention due to its strain-hardening characteristics, good post-cracking resistance unique properties. Bonding between rebar great effect on the mechanical behavior of structural members. In this paper, direct pull-out tests were conducted understand bond ECC rebar. The test parameters included diameter type, cover layer thickness, embedment length fiber volume content. Bond-slip curves,...

Precast high-strength concrete segmental beams with external tendons and dry joints (ED-PHCSBs) have become a potential alternative for achieving accelerated bridge construction due to their lighter self-weight easier installation. In order investigate the shear behavior of ED-PHCSBs, eight precast specimens were fabricated tested failure. For comparison purposes, one externally prestressed monolithic beam was also investigated. The primary parameters, including strength, span-depth ratio,...

In recent years, replacing steel bars with basalt fiber-reinforced polymer (BFRP) and ordinary concrete reactive powder (RPC) are considered effective solutions to the corrosion problem of in reinforced structures. order study bonding performance between BFRP RPC, a total 27 specimens were tested by pull-out test. The effects fiber volume content (0%, 1.5%, 2%), protective layer thickness (25 mm, 40 55 69 mm), bond anchorage length (3 d, 4 5 d; d is diameter bars) on studied. experimental...

Due to the extraordinary mechanical properties of ultra-high-performance concrete (UHPC), shear stirrups in UHPC beams could potentially be removed. The aim this study is determine effect beam height and steel fiber volume content on behavior non-stirrup under a larger span-depth ratio (up 2.8). Eight were designed fabricated, including six two comparing stirrup-reinforced normal (NC) beams. experimental results demonstrated that crucial factor affecting ductility, cracking strength,...

When exposed to sulfuric acid environments, the service life of concrete structures would be reduced due high alkalinity concrete. The influence three factors including water/cement ratio, pH value solution, and chemical composition aggregate on resistance subjected has been widely investigated by previous researchers. This paper aims investigate these durability evaluation indicators mass loss surface fractal dimension through orthogonal experiments, which reported rarely in research. Four...

This study aimed to investigate the different performance of pile–soil interfaces when concrete was subjected sulfuric acid corrosion. A series large-scale direct shear tests were carried out influence corrosion on interface between soil and pile. Concrete specimens immersed in solution for durations (0, 31, 93 154 days) used simulate pile surface roughness under environment, which would be more realistic than artificially roughened surfaces. Sand soil. Geometric models attacked by captured...

With the development of automotive industry, a large amount waste rubber is produced every year. The application and recycled concrete (RRC) can effectively reduce 'black pollution' caused by rubber. However, addition particles lead to decrease in compressive behavior concrete. Previous research has demonstrated that preventing crack growth, fiber increase strength ductility In this work, total 28 RRC mixes are designed, reinforced steel fibers (SFs) glass (GFs) investigated. workability...

Fixing imperfections in keyed dry joints between the concrete segments compromise performance of precast segmental bridges (PCSBs), which needs to consider carefully. In this study, a finite-element model on high-strength single-keyed PCSBs was established and validated by experimental results. Parametric studies fixing key, strengths, confining pressures were carried out based that model. The numeric results included crack patterns, load-displacements shear strength. imperfections-...