To study the bond performance of ultra-high concrete (UHPC) and steel bar after freeze-thaw cycles (FTCs), eccentric pull-out test 10 groups reinforced UHPC specimens, compressive 24 cube specimens splitting tensile were carried out. The degradation mechanical properties FTCs studied. influence strength, cover thickness, length on strength was analyzed. relationship between is established by using average as indexes. A formula for calculating developed. results show that elastic modulus...

Abstract In this study, a 2D hydrodynamic and water quality model was built based on MIKE 21 to investigate the relationship between condition quality, then applied in an urban landscape lake Tianjin, China. Moreover, engineering experiment carried out confirm comprehensive degradation coefficients of chemical oxygen demand (COD), total phosphorus (TP), nitrogen ammonia (NH4+-N), (TN) (0.014 d−1, 0.024 0.019 0.005 respective). Circulation system main force that expedited changes pollutant...

This study employed the rapid chloride ion penetration test and salt spray erosion method to examine electric flux changes in mineral-admixed reactive powder concrete (RPC). Variations content diffusion coefficient under different durations depths were also investigated. The impact of mineral admixtures on resistance was explored. Notably, after mixing fly ash (FA) granulated blast furnace slag (GGBS), values RPC each group significantly reduced, mixed lower than those single reference...

<title>Abstract</title> To study the influence of fly ash content on performance high-performance concrete (HPC), Seven groups tests were conducted to evaluate macroscopic properties (workability and compressive strength) microscopic pore structure. Low field nuclear magnetic resonance (NMR) technology SEM images used analyze changes in internal structure concrete. The results show that workability HPC initially increases then decreases with increase content. When is 15%, slump reaches a...

The corrosion characteristics of cast iron pipes in reclaimed water containing 1, 2, and 4 mg/L NaClO ClO were investigated using potentiodynamic polarization curves (PPCs) electrochemical impedance spectra (EISs). Scanning electron microscopy (SEM) was also used to evaluate the morphology scales. results showed that utilization changed electron-transfer pathway corrosion-product significantly. In at HClO could take precedence over dissolved oxygen (DO) react with Fe enhance process days....

A design approach for determining the optimal flow pattern in a landscape lake is proposed based on FLUENT simulation, multiple objective optimization, and parallel computing. This paper formulates into multi-objective optimization problem, with circulation effects operation cost as two objectives, solves problem non-dominated sorting genetic algorithm II. The modelled FLUENT. parallelization aims at instance runs, which different from internal solver. approach: (1) proposes metrics, i.e....

Abstract To assess the spatial distribution characteristics and health risk of heavy metals (Cu, Zn, Ni, Cd, Pb, Cr) in surface sediment Hai River its tributaries Tianjin, China, 32 samples were collected. All mainly occurred residue, except Cd. Cd primarily existed exchangeable fraction posed a high to aquatic environment. The mean values pollution index followed decreasing trend Cu &amp;gt; Ni Pb Cr Zn. results assessment showed that not threat local residents main contributors risk....

To investigate the influence of fly ash (FA) content on performance high-performance concrete (HPC), seven groups tests were conducted, aiming to evaluate both macroscopic properties (workability and compressive strength) microscopic pore structure. Low-field nuclear magnetic resonance (NMR) technology SEM images employed analyze changes in internal structure concrete. The results showed that workability HPC initially increased then decreased with increase FA content. When was 15%, slump...

The urban landscape water usually lacks necessary cycle and speed is closed to zero, which easily lead eutrophication in system deterioration of quality. Therefore, understanding the impact circulation on quality great significance. With that significance, this research has been done investigate relationship between hydrodynamic conditions based adopted indexes such as chemical oxygen demand (COD), total nitrogen (TN), phosphorus (TP) nitrogen-ammonia (NH3-N). Moreover, MIKE 21 model used...

In this article, artificial wetland and landscape river were used to build the water circulation system maintain improve quality of urban prevent eutrophication. According Liebig law minimum, it could be determined that TP played an important role in process eutrophication (total phosphorus) was primary constraint condition control After operated, content detected. The result showed became stable. Compared with stagnant waters, through 6 times samplings, TP, ammonia nitrogen lower than...

Abstract Extensively application of reclaimed water alleviated scarcity obviously. While, bacterial proliferation in distribution systems (RWDSs) poses a threat to safety. Disinfection is the most common method control microbial growth. The present study investigated efficiency and mechanisms two widely used disinfectants: sodium hypochlorite (NaClO) chlorine dioxide (ClO 2 ) on community cell integrity effluents RWDSs through high-throughput sequencing (Hiseq) flow cytometry respectively....

Growing demand for reclaimed water occurred in the situation of alleviation global scarcity dilemma. Thus, presented study investigates efficiency and mechanism two commonly used disinfectants (NaClO ClO2) on bacterial community cell integrity effluents RWDSs through Hiseq sequencing technology flow cytometry technology. Results from showed that continuous disinfection affected obviously effluents. 1 mg/L disinfectant dosing could not affect microbial abundance basically, while 2 reduced...