Abstract:To explore the gusset plate buckling and its influence factors under compression caused by bracing members in braced frames,and to obtain an appropriate buckling design method,the buckling behaviors of gusset plates with varied parameters are computed by eigenvalue analysis and nonlinear analysis.With the capacity eigenvalue of elastic buckling,the effective length factor of assumed plate-column of gusset plate is derived from Euler’s formula.The influences of some key parameters on the effective length factor are studied,and a simplified bilinear formula used to calculate the effective length factor is proposed.The exact solutions of buckling capacities taking into account of the material and geometrical nonlinearities are attained by nonlinear analysis program,the buckling influence factors of the gusset plates are evaluated,and the rationality of the designed buckling capacities with the proposed effective length factors is verified.

Abstract:To study the cracking behavior of concrete beams reinforced with GFRP/steel wire composite rebar,five simply-supported beams were tested under three-point static load.The test variables were beam section size and concrete cover depth.Based on analysis on the test results,the calculation methods of cracking capacity and maximum crack width were proposed,and the limit value of crack width was suggested.

Abstract:For keeping strengthening role of Carbon Fiber Sheet(CFS) bonded with an inorganic adhesive to insure fire safe of structure,thick-typed fireproof coating is needed for protecting CFS.Considering deformation limit of strengthened slabs in fire,temperature on bottom surface of slabs is limited to 415 ℃ by trial calculation of deformation by ABAQUS.By analysis of temperature field of strengthened slabs by ABAQUS,fireproof coating thickness,heat conductivity coefficient and fire duration are the main factors affecting temperature on bottom surface of strengthened slabs,so key factors affecting fireproof coating thickness are heat conductivity coefficient and fire duration.Based on that,in terms of fire endurance and thermal conductivity coefficient of coating,and considering actual construction demand,advised values of fireproof coating thickness are proposed in terms of different type of coating.

Abstract:The reinforced gradient concrete beam consists of normal concrete tensile region and high concrete compressive zone.This new flexural member may easily satisfy the requirement of the depth of the limiting compressive zone in reinforced concrete flexural element.The experiment of simple beam with reinforced gradient concrete was carried out.Ultimate compressive strain,maximum deflection and strains of round stirrup are measured.Assumption on plane before loading remaining plane under ultimate load and harmony of two concretes were analyzed emphatically.The calculation method of ultimate load-bearing capacity of such flexural member is proposed.Plastic hinge rotation capacity and curvature ductility are analyzed.It can be served as calculation for ultimate limit state of reinforcing gradient concrete flexural members.

Abstract:To further promote the use of recycled concrete in practice,Pseudo-static tests were carried out for 4 natural RC’s(reinforced concrete) columns and 8 recycled RC’s columns.During the institute of building type test,the Load(P)-displacement(Δ) relationship curves to each specimen were obtained,and the breakage mode,hysteresis loop,skeleton curves,energy dissipation,stiffness retrogression,ductility performance and carrying capacity of each specimen were similar to those of the natural RC’s columns.In small axial ratio,the bradage mode was brittleness default,and in large axial ratio,the mode was ductility breakage.The ductility performance of recycled concrete is poor to the natural concrete.The fly ash could improve the ductility performance but lower the carrying capacity.In conclusion,the seismic behavior of recycled aggregate RC’s column is apparently similar to that of natural RC’s column.

Abstract:To research the influence of concrete slab on the behavior of panel zone in steel moment frame structures,the effective width of composite connections was proposed by finite element analysis.Based on analysis within elastic and post-elastic range of the panel zone,a new model,which is particularly suited for modelling steel and composite joints within frame analysis procedures,is proposed,and the formulae calculating the shearing stiffness and ultimate strength of the composite joints are derived.The results demonstrate that the approach provides a more realistic representation of the behavior in comparison with the available models,especially in the case of composite connections.Shear force in panel zone with slab is smaller than that without slab under the same moment loads.

Abstract:A pilot-scale membrane adsorption bioreactor(MABR) was carried out for the drinking water treatment from Dong River water with coagulation-sedimentation as pre-treatment.During the experiments,the MABR exhibited much higher capacity for organic matter removal as compared with the conventional sand-filtration and ultra-filtration alone,with the average removal efficiencies of 72.4% and 89.1% for CODMn and UV254,respectively.During the stable operation period after start-up,the MABR also achieved excellent removal for the influent NH3-N and NO-2-N,the effluent concentrations were maintained below 0.2 mg/L and 0.05 mg/L,respectively.In the investigation,the membrane in MABR was operated under the conditions of constant flux(20 L/(m2·h)),continuous aeration(12.5 m3/(m2·h),calculated based on the bottom area of the membrane tank),and backwashing for 5 min after every 8 h of filtration.Under these conditions,obvious membrane fouling was observed for the membrane,with the average trans-membrane pressure development rate of 0.51 kPa/d.To mitigate membrane fouling and to decrease the chemical cleaning time,it is required to further optimize relevant operating parameters of the membrane in MABR.

Abstract:To evaluate the feasibility of hybrid process of coagulation,sedimentation and immersed ultrafiltration(UF) for the drinking water treatment from Bei River source water,pilot study was performed in terms of pollutants removal and membrane fouling.The performance of the hybrid UF process was also compared with that of the conventional process in the full-scale drinking water treatment plant.Results showed that in the conventional treatment process,there was still 0.176 NTU of turbidity in the sand-filtration effluent on average;while it was only 0.080 NTU in the hybrid UF process.The removal efficiencies of conventional treatment process for CODMnand UV254 were 47.5% and 42.3%,respectively,which were slightly lower than the 50.6% and 44.0% achieved by the hybrid UF process.As for the membrane fouling,it was shown that the trans-membrane pressure(PTM) would increase rapidly when direct UF of raw water was carried out.However,in the hybrid UF process,due to the pre-removal of membrane foulants by coagulation and sedimentation,the PTM development rate became much lower;and stable operation of the UF could be achieved.It is demonstrated that the hybrid UF process can improve the security of drinking water supply.

Abstract:It was difficult to develop a normal parametric model to match the results well for the complex non-linear relationship among the inlet concentration,retention time and removal efficiency of hydrogen sulfide in the biotrickling filter.Aiming at this problem,back-propagation neural network(BPNN) was introduced into the research.A non-parametric model was established by the training of BPNN with the experimental data.And this model could simulate and predict the experimental results well.The correlation coefficient of simulation with all experimental data was 0.986 0.In nine different experimental conditions,the linear regression correlation coefficient of network predicted values and the corresponding experimental results was as high as 0.965 9.

Abstract:In order to improve waterworks’ ability of emergency response to ethylbenzene pollution,the efficiency of ethylbenzene adsorption onto PAC was experimentally studied.Bench experiments were conducted to estimate the removal of chlorbenzene by conventional water treatment process and to determine isotherm and kinetics for ethylbenzene adsorption onto powdered activated carbon(PAC).A theoretical formula of PAC dose with initial concentration of ethylbenzene and adsorption time was established and verified by experimental results.The results show that it is difficult for conventional water treatment process to remove ethylbenzene effectively;PAC can adsorb ethylbenzene in raw water rapidly with 80% and 95% of the equilibrium adsorption capacity at 5 min and 30 min,respectively;PAC adsorption is an effective emergency drinking water treatment technology for water works to cope with ethylbenzene sudden pollution in raw water.

Abstract:To improve the wastewater treatment efficiency and enhance the resource recovery efficiency,this paper studied the effects of trace elements,Fe,Mn,Cu,Zn,Co,Mg,on photosynthetic bacteria(PSB) growth in wastewater.Two most prominent factors that influence the biomass of PSB were identified through single element design.Optimal concentrations of these trace elements were found through the Box-Behnken design and the response surface analysis.The results showed that the best situation was as follows: 0.66 mmol·L-1 Fe2+and 0.16 mmol·L-1 Mg2+,the maximum biomass of PSB reached 1 483.5 mg/L,the maximum COD removal ratio was 89.1%,and the additional cost was RMB 0.033 Yuan/t.The confirmatory tests showed that the combination of Fe and Mg achieved a PSB biomass of 1 380 mg·L-1after 72 h,which was 57% higher than the control.Fe and Mg could promote PSB growth in wastewater and enhance the resource recovery efficiency.

Abstract:To evaluate the working state after turning off some valves in an urban water distribution system(WDS) when there was a pipeline breakage,this paper established a failure consequence evaluation model,in which the node demands decrease of affected pipelines,the node demands decrease and the pressure reduction of non-affected pipelines were taken as three estimate indexes.And because all the variables were the node’s properties,their values were easier to get from the hydraulic model.As a basis for the model,a micro-hydraulic model named water supply pipeline failure hydraulic model was established.It redistributed node demands firstly,and then automatically adjusted the node demands under node pressure,and was calculated by genetic algorithm(GA).By the simulation experiments in a small water distribution system,it showed that the assessment model worked well.According to the results,the reasonableness of the valve’s arrangement and the role of some pipelines in the network can be effectively analyzed.

Abstract:To reduce environmental pressure and realize sustainable development of corn deep processing industry,a corn deep processing enterprise with average scale in China was selected to study in this paper.The metabolic models for the production of the corn deep processing enterprise were established using Material Flow Analysis Method.The material and energy consumption indicators,waste and emission indicators and material balance indicators were calculated according to the formula of MFA index,and the results were shown as follows: water consumption per unit of product is 5.4 m3/t,steam consumption per unit of product is 3.94 m3/t,electricity consumption per unit of product is 388 kW·h/t,wastewater generation is 11 139.7 m3/d,wastewater generation per unit of product is 14.78 t/t,air emission per unit of product is 0.005 t/t,solid waste generation per unit of product is 0.123 t/t,recirculating cooling water efficiency is 98.9%,and resource utilization rate is 15.3%.Based on the results,the strategy of enhancing material and energy utilization efficiency and reducing the environment pressure could be proposed.

Abstract:The sorption of alachlor is one of the most important behaviors of transference and transformation of alachlor in soils,and it also plays significant role in the soil environment.Three soil samples were collected from the suburb farmland of Jiamusi(S1),Yilan(S2) and Harbin(S3) along the Songhua River(Northeast,China),and batch experiments were conducted to investigate the effects of dissolved organic matter(DOM) on the adsorption-desorption behavior of alachlor in soil-water system.The results showed that the adsorption capacity of alachlor was suppressed significantly after adding DOM into soil-water system,yet the DOM might accelerate the desorption process of alachlor from soil.The adsorption and desorption isotherms for alachlor in the soil samples were found to fit well with the Freundlich model(R2>0.858)and the order of adsorption capacity of the soil samples was in the order of S1>S2>S3.Hysteresis Index showed that the hysteresis existed in the adsorption-desorption process of alachlor.

Abstract:Partial nitritation is the basis of anoxic ammonium oxidation(Anammox),however,very limited research has been undertaken on this field.In this study,an A/O reactor was used to investigate the feasibility of the partial nitritation and the performance of biological phosphorus removal from municipal wastewater.The obtained results showed that the partial nitritation could be achieved in A/O reactor with nitrite accumulation rate of 85%.It was possible that nitrite-to-ammonium ratio in the effluent from the A/O reactor was approximately controlled at 1.0 by adjusting hydraulic retention time,which was beneficial to the Anammox reaction.The fluctuation of temperature and DO concentration might lead to the deterioration of nitritation.After the achievement of partial nitritation,the biological phosphorus removal was not stable,which might relate to the increase of FNA concentration in the effluent of A/O reactor,and needed further experimental investigation.

Abstract:The research trend of FA inhibitions on nitrifies were introduced,including the inhibition mechanism and inhibition mathematic model of ammonia-oxidizing bacteria and nitrite-oxidizing bacteria,as well as the strategy to reduce or avoid inhibition effects.In addition,the selective inhibition effects of FA on the start-up and stability of partial nitrification were illuminated.In particular,the combinative effects of FA inhibition and other factors(such as dissolved oxygen and temperature) on short-cut nitrification were presented in the review.

Abstract:The A2N process with BAF as a nitrification unit was researched aiming at the low carbon and nitrogen ratio domestic wastewater in southern China.According to the problems that effluent ammonia exceeded the standard because of the ammonia carried in surpass sludge and total phosphate couldn’t reach the discharge standard when SS of secondary settling tank was high,a secondary BAF was set up,and the total treatment effect of A2N/BAF process was studied.Results showed that the average removal rates of COD,ammonia and TP of A2N stage were 82.0%,70.9% and 90.0%,respectively.Effluent ammonia concentration of secondary settling tank exceeded 10 mg/L when influent was more than 40 mg/L.Average concentration of COD,TP,ammonia,nitrate and SS in final effluent were 35,0.35,1.06,8.01 and 7 mg/L,respectively,which had satisfied the A-level of the national standards.

Abstract:To overcome the shortcoming of biological aerated filter(BAF) on phosphorus removal,poly aluminum chloride(PAC) was dosed into the anoxic tank of anoxic-biological aerated filter(A-BAF).The effects of PAC on the phosphorus,organic matter and nitrogen removal by A-BAF and the head-loss development of BAF were investigated through a lab-scale experiment.The results showed that the addition of PAC had a positive effect on phosphorus removal by A-BAF,but had no effect on the removal of organic matter and nitrogen.With the PAC dosage of 100 mg/L,the TP concentration in effluent was reduced from 2.57 mg/L to 0.34 mg/L,when the influent TP concentration was 3.5 mg/L.The COD,NH+4-N and TN concentration in effluent were 30,1 and 11 mg/L separately,which were similar to those in the effluent without PAC.Meanwhile,the backwashing cycle of BAF was increased from 4 d to 10 d and the specific resistance to filtration of the excess sludge was decreased from 210×1012m/kg to 125×1012m/kg after PAC dosing.

Abstract:ANAMMOX bacteria is a kind of microorganisms that are related to the order Planctomycetales,able to autotrophically one-to-one combine ammonium and nitrite into dinitrogen gas.Based on ANAMMOX bacteria,ANAMMOX process is believed to be a shortcut pathway for biological nitrogen removal.Since most wastewater contains organic matter,it is of importance to understand the specific impact of organic matter on ANAMMOX bacteria.In an ANAMMOX reactor,large amount of organic matter could inhibit ANAMMOX activity,while such inhibitory is reversible.To date,among the five discovered ANAMMOX genera,four are demonstrated to be able to oxidize short chain organic matter,such as formate,acetate and propionate.This paper reviews the state-of-art of impact of organic matter on ANAMMOX bacteria,especially focuses on the catabolism of organic matter by ANAMMOX bacteria and the perspective application of such technology on the treatment of high nitrogen-carbon ratio wastewater.

Abstract:Endocrine disrupter chemicals(EDCs),with the characterization of low concentration,high toxicity,difficulty in removal from water,are receiving more and more attentions all over the world.The current study investigated the distribution of estrogenicity during wastewater treatment processes in Harbin using solid phase extraction/recombinant yeast system and analyzed the removal pathways of estrogenicity according to the results.Results showed that most of estrogenicity was distributed to liquid phase,whereas only(7.7±5.5) % of total estrogenicity was in the solid phase;it was also found that the secondary bio-process played a crucial role in the removal of estrogenicity,where the removal of estrogenicity took place mainly by biodegradation(73.9 %),whereas only 1.2 % was made through residual sludge adsorption.Last but not least,by calculating the removal of estrogenicity,it confirmed that less than 15 % of estrogenicity was removed through volatilization and adsorption,but mainly by biodegradation.Anyway,the estrogenicity of wastewater treatment plant effluent is still high(3.37-6.76 ng·L-1),so that the enhanced biotreatment processes or advanced treatment processes are desired to decrease the risk of estrogenicity.

Abstract:To achieve more accurate algae concentration prediction models for satisfying with the needs of water bodies with different nutrients’ characteristics,the algae prediction models were modified by introducing related correction factors under controlled initial conditions in the microcosm environment.Results showed that the prediction model was more precise by introducing total nitrogen(TN) as the correction factor when the ratio of nitrogen to phosphorus was 5∶ 1,while the model was more accurate by introducing total phosphorus(TP) when the ratio of nitrogen to phosphorus was 15∶ 1 and 25∶ 1.The algae concentration prediction models under controlled initial conditions in the microcosm environment were helpful to predict algae concentration accurately for water plants.

Abstract:To improve connectivity-reliability of gas pipeline network the possibility of gas pipe network with intermediate state before failure is expounded.Based on the improved two states with safety and failure of pipe unit,a three-stage connectivity reliability work mode of safety-intermediate-failure is established.Through adopting hierarchical exploded mode of full probability,multi-loop gas pipe network with bridge circuit can be broken down into several simple compound pipe systems for reliability vector solving.The influence of correlation parameter among pipe units to connectivity reliability of gas pipe network is considered and the trust in connectivity reliability calculation is increased in this paper.

Abstract:In severe cold zone,building’s heating load is much bigger than cooling load.Heating performance of solar-ground coupled heat pump system(SGCHPS) declines year after year and even can’t afford the heating load.In order to solve this problem,a method of depending on solar seasonal heat storage in soil was put forward to maintain soil heat balance and increase system efficiency.Relying on a demonstration project of solar-ground coupled heat pump for heating and cooling in severe cold zone,long-term experiment on heat storage,heating and cooling of 3 years was carried out.On the basis of ensuring heating and cooling effect,the experimental results showed that the soil temperature changed daily and annually.And the soil maintained heat balance in an annual cycle.Solar energy accounted for 85% of the total heat supply in winter.In the cooling season,the ratio of ground heat exchanger(GHE) for heat storage and cooling can be distributed according to heat transfer rates.Heat storage in soil solved the imbalance of heating and cooling loads in severe cold zone.The system could operate efficiently for a long period.Solar energy of the whole year was utilized,which saved a lot of conventional energy.

Abstract:The method of calculating interchange noise was studied according to geometric alignment.By using vehicle speed as starting point,the relationship was fitted between noise levels and vehicle speed.For the calculation of ramp noise,the thesis defined the concepts and calculation method of relative equivalent sound energy according to the definition of equivalent sound level,determined the total noise energy by using the method of adding noise energy in uniform motion segment to the one in variable motion segment,and established the functional relationship between relative equivalent energy and the length of ramps.Under the definition of equivalent sound level,the noise level of left-turn ramp and right-turn ramp were deduced by the method of ramp length integral operation.For the calculation of the main line noise,the formula of the main line noise level was deduced according to the relationship among the mainline design speed,noise level and vehicle speed.The total interchange noise was obtained by the superposition of noise level in each main line and ramp.Heda interchange in Heilongjiang province was taken for example.The result shows that this method can solve the calculation problem of noise pollution in interchange ramp variable motion segment,and can connect the noise pollution produced by traveling vehicles with the interchange geometric alignment.When the interchange geometric alignment design conditions are known,the noise pollution can be calculated and the results can be used to quantitatively evaluate the degree of interchange noise pollution.

Abstract:Because the electrochemical oxidation technology is an effective and reliable clean technology,this study proposed electrochemical oxidation activated sludge process in electrolysis reactor with homocentric circle arrangement electrode in which Ti/RuO2 was used as reticular plates.The results showed that the electrochemical oxidation could significantly reduce activated sludge production.The activated sludge solution efficiency achieved to 29.98% in the experiment under the following optimal oxidation conditions: pH=12,60 min of intermittent electrolysis time,working voltage 6 V and initial MLVSS concentration of 4 670 mg·L-1.Under above conditions,the SCOD and TP released from cell dissolve got the maximum 712.2 and 33 mg·L-1,respectively;meanwhile,the NH3-N also reached the maximum and presented a declining trend,which showed that these conditions were the best electrolysis conditions.

Abstract:A polymorphism of κ-casein gene CSN3 exon IV was identified in Chinese Maiwa Yak by PCR-restriction fragment length polymorphism protocol to reveal the distribution of diversity of κ-casein in Maiwa Yak at the DNA sequence level.The sequences corresponding to the coding region of κ-casein gene exon IV were used for phylogenetic analysis to establish the phylogenetic relationship of CSN3 variants in the Bos genus.Experimental results indicated that most yak milks were with κ-casein BB genotype.A new variant was identified in Maiwa yak breed by analysis and entered into GenBank with accession number GU441771.The phylogenetic analysis presented κ-casein evolution was consistent with species at a degree.

Abstract:In order to improve the accuracy,efficiency and maneuverability of risk estimation of highway bridges,a response surface method and the improved Delphi method based framework for risk assessment of highway bridges is proposed.The flowchart of damage risk probability analysis of bridges based on response surface method is presented.The improved Delphi method is proposed to estimate the risk of highway bridges.The results of expert survey are adjusted by an optimization model,then the grade of risk loss is estimated quantificationally using the improved Delphi method.The damage risk assessment under earthquake of a self-anchored suspension bridge is carried out for illustrating the application and efficiency of the proposed methodology.The illustrative example indicates that not only the specific characteristics of the bridge but also the objective existence of uncertainty are considered by the response surface method based bridge damage probability estimation method,structural damage risk probability is calculated quantitatively taking full advantage of existing research results;The improved Delphi method overcomes the deficiencies of the traditional Delphi method,the statistical and computational workload are reduced while the reliability of expert opinions are ensured,so the time required for risk estimation is shortened to improve the efficiency of the risk assessment.

Abstract:To reduce the computational complexity of scalable video coding(SVC),a novel fast mode decision algorithm for H.264 scalable video coding is proposed.First,according to the analysis of mode occurrence frequency and conditional probability,the frequently occurred modes were examined at priority.If both the local-optimal condition and the monotony of rate-distortion cost condition were satisfied,the mode search process was terminated.Moreover,the candidate modes were selected based on the inter-layer mode correlation and the not suitable modes were eliminated.Comparing with the full mode search method,the proposed method accelerates the coding speed remarkably with negligible loss of quality and bit-rate.

Abstract:In order to improve the intersection control efficiency,the concept of integrated saturation degree is established based on the derivation of traffic wave behind stop line.This index can reflect the temporal resource usage as well as spatial usage.Then delay minimization isolated intersection control method with equal integrated saturation degree constraint was established.The iterative method was used to solve this constraint due to the non linear feature.Numerical example was carried out to compare the control benefit.Results show the proposed method can efficiently decrease queue length during rush hours.

Abstract:Based on the entropy production minimization approach for heat exchanger optimization design and relationship between the entropy production uniformity and heat exchanger performance by Tondeur and Kvaalen,an entropy production uniformity factor is defined and used to optimize Double-chevron Plate Heat Exchangers(DPHE) with different β(corrugation angles).Optimized results based on the entropy production uniformity Criteria and the Performance Evaluation Criteria show that the performance of DPHE with β=30° and β=70° are the best.The Be(irreversibility distribution ratio) decrease as Re and β increase.

Abstract:In order to reveal collapse mechanism in loose wall rock of shallow tunnel under rainfall,the cusp-catastrophic model is established based on catastrophe theory.Considering the case that surrounding rock of shallow tunnel is combined with different rock and soil mass,the instability criterions are derived when surrounding rock is combined with double strain-softening mediums or with single strain-hardening layer and strain-softening layer.The main influence factors and mechanism of collapse are analyzed.Then,the viewpoint is put forward that collapse of shallow tunnel can be predicted by data of ground settlement based on the catastrophe theory.It’s feasibility and reasonability is tested by the collapse that occurs in construction of Maanshan tunnel.The results show that the derived instability criterions can analyze the collapse mechanism effectively.It is more feasible and tally with the actual that the data of ground settlement is used to predict the collapse in loose wall rock of shallow tunnel.