Journal of University of Babylon

This study presents a computer program designed in Visual Basic 6 program. The capability of this ‎program is to design wastewater treatment plant units in two cases: the first case is with primary ‎sedimentation tanks and the second case is without primary sedimentation tanks to assess primary ‎sedimentation tanks effects on biological treatment ‎
The program deals with two types of wasted sludge the first type is wasted sludge from the ‎aeration basin, while The second system is wasted sludge from the secondary clarifier. Also there is a ‎detailed output shows the design flowrate, mass balance analysis and composition of each stream in and ‎out of each treatment unit. Program results are verified with hand calculations within the allowable ‎recommended values and they showed a good accuracy.‎
Single regression analysis is made to 22 models to find the relationship between independent ‎variables (the influent flow rates, BOD¬5 and TSS) and dependent variables (volume of each treatment unit) ‎considering presence and absence of primary sedimentation tanks with different values of TSSinf and BOD-‎‎5inf. Relationships between the influent and volume of each unit are found using (Microsoft Excel 2003) ‎program for statistical calculations which showed a good degree of accuracy.‎
‎ The volume of aeration basin and secondary sedimentation tank will increase if primary ‎sedimentation tank is to be eliminated from the design of the wastewater treatment plant. This increment in ‎volume varied according to the influent and effluent characteristics. Generally an increments about (52 – ‎‎170) % for aeration basins and (58-185) % for secondary sedimentation tanks are observed in the present ‎study. Also, the volume of each sludge treatment unit is decreased when primary sedimentation is omitted ‎in the design of plant. The amount of decreasing is also depending on influent, effluent characteristics. ‎Approximately gravity thickener volume is decreased by (29-42) %, anaerobic digester volume is decreased ‎about (38 - 52) % and drying beds is decreased by (29-38) %‎
Construction cost analysis is made to compare between the cost of a wastewater treatment plant ‎design including primary sedimentation and another without primary sedimentation tank. The cost analysis ‎showed that the cost of a wastewater treatment plant is increased after a certain amount of influent. That ‎amount is nearly (36,708.33) m3/d when wasted sludge is taken from aeration basin and (24,833.33) m3/d ‎when wasted sludge is taken from secondary clarifier, also, the above mentioned values depend on influent ‎and effluent characteristics.‎
Finally it is found that the mixing of primary sludge with that of secondary sludge will give better results as ‎compared with sludge treatment that obtained from secondary sludge only.‎

‎ This research work is aims to develop mathematical models for prediction of the some mechanical ‎properties of high strength of concrete after burning by fire flame. These models used linear and non-linear ‎regression equations by statistical program called (DATA FIT 9.0.59, 2009) to evaluate good coefficient ‎correlation with fewer variables introduced in them. The concrete specimens were subjected to fire flame ‎temperatures ranging from (25-850 °C) at different ages of 30, 60 and 90 days. Three temperature levels of ‎‎400°C, 600°C and 850°C were chosen of exposure duration of 2.0 hours. After burning, the concrete ‎specimens were quenched in a water tank to provide the maximum shock due to sudden cooling. The test ‎results showed that the density, compressive strength, tensile and flexural strength decreases when the fire ‎flame temperatures were increased‏.‏‎ Mathematical models were proposed to predict the compressive strength, ‎splitting tensile strength and flexural strength of concrete after exposure to fire flame. The compressive ‎strength test results of this study together with results obtained by other investigators were compared with ‎CEB strength reduction curve and that of CEN. It was noticed that the test results agreed with CEN design ‎curve rather than with that of CEB. ‎

‎ In this paper, it was aimed at studying the influence of cement kiln dust (CKD) on workability of ‎fresh concrete and some mechanical properties of self compacting concrete, CKD is by product from ‎the cement factory. The work consist of using different mixtures having CKD of (10,20,30%) by ‎weight of cementations materials .‎
‎ Different test was used to study the different workability parameters. The mechanical properties ‎studied in this work, are compressive strength, splitting tensile, flexural strength, and modulus of ‎elasticity at ages 7 to 60 days. Furthermore the ultrasonic pulse velocity was used to assess the ‎properties of the SCC. It was possible to produce SCC with CKD add on which satisfies the ‎requirement of this types of concrete, however the compressive strength was ranged ( 32 - 60 ) MPa, ‎splitting tensile ranged ( 2.1- 3.4 )MPa , modulus of rupture ranged ( 3.75- 7.5 )MPa. ‎

This study is used to construct a mathematical model to analyze flow through air gap inside in ‎horizontal annuals with triangular radial fins attached to inner cylinder ,the cylinders has constant ‎temperature. This study used when the inner cylinder more hotter than outer cylinder and contrarily for ‎to Rayleigh number 3 x107,This study illustrate effect the length , number of fins and its arrangements ‎on the inner cylinder on convection heat transfer in air gap .This study include using the case of free ‎convection through horizontal annulus, the governing equations of flow and heat transfer across the ‎annulus which were simplified from the general equations (conservation of mass, momentum and ‎energy equations) using polar coordinates. The governing equations were transformed to the vorticity-‎stream function formula as for momentum equations and to the temperature and stream function for ‎energy equation. ‎
The construct result used program(ANSYS 5.4) to find temperature, velocity and pressure distribution ‎also the vector of velocity inside the air gap for several cases. Firstly the inner cylinder has eight ‎triangular fins has length 0.01 m , 0.015 m the inner cylinder more hotter than outer cylinder and ‎contrarily . Secondly the inner cylinder has four triangular fins has length 0.01m ,0.015m in x,y axis ‎‎,the inner cylinder more heater than otter cylinder and contrarily .Thirdly the inner cylinder has four ‎triangular fins has length 0.01,0.015 in inclined on x,y axis ,the inner cylinder more hotter than outer ‎cylinder and contrarily, and forth the cylinder has no fins. ‎

In this study Box-Jenkins seasonal model is applied to records of mean flow to Dokan reservoir in the ‎north of Iraq for the period from water year 1953/1954 to water year 2004/2005.Seven Box-Jenkins seasonal ‎multiplicative models are fitted to this series. These are (1,1,1)×(1,1,1)12 , (1,1,1)×(0,1,1)12, ‎‎(1,1,2)×(0,1,1)12,(0,1,1)×(0,1,1)12,(2,1,0)×(1,1,0)12,(1,1,0)×(1,1,0)12,(1,1,1)×(0,1,0)12 models. The unconditional ‎sum of squares method is used to estimate the parameters of the models and to compute the sum of square ‎errors for each of the fitted model. It is found that the model which corresponds to the minimum sum of ‎squared errors is the (1,1,1)×(1,1,1)12 model with parameters θ=0.899,Φ=0.60,Θ=0.96, and Φ=0.03 . ‎Portmanteau lack of fit test is used as diagnostic checking. Forecasts of monthly inflow for the period from ‎October, 2005, to September,2007 are graphically compared with observed inflow for the same period and ‎since agreement is very good adequacy of the selected model is confirmed. ‎

The application and design of precast, prestressed hollow core slabs is similar to that of other ‎prestressed members. However, there are situations which are unique to hollow core slabs either because of ‎the way the slabs are produced or because of the application of the slabs. For special situations, hollow ‎core producers have developed design criteria and conducted in house testing to verify that their ‎approaches are valid. In fact, there is consistency between the many types of hollow core slabs available. ‎
This research work is intended to cover the primary design requirements for hollow core floor and roof ‎systems. Where, it was carried out by computerized finite element model for the hollow-core slab, ordinary ‎reinforced and prestressed. On which a design aids were prepared and arranged in a manner to be used in ‎simple way. All reasonable care has been used to verify the accuracy of material contained in the research. ‎However, the obtained data should be used only by those experienced in structural design and should not ‎replace good structural engineering judgment. ‎
In this study, charts for the design of one and two-end continuous hollow-core slabs were developed ‎by the using of analysis and redesign by the finite element technique. These charts enable to find the ‎required moment capacity at supports and the moment redistribution from supports to be determined for a ‎desired increase in span length.‎

Concrete made with natural aggregate originating from hard rock has a density within a narrow range ‎because the specific gravity of most rocks varies little.‎
‎ Although the volumetric content of the aggregate in the mix affects the density of the concrete, ‎this, too, is not a major factor. Thus, in practice, the density of normal weight concrete lies within the ‎range of 2200 to 2600 kg/m3.‎
‎ The use of sintered rice husk ash aggregate in concrete as a partial replacement of granite aggregate ‎has been examined. The Concrete so produced is light in nature (up to 12% reduction in unit weight) ‎and the development of such concrete with sintered aggregate minimizes the consumption of granite ‎rock, resulting in protection of the natural environment due to using a large amount of rice husk ash. ‎
‎ It is observed from the present investigation that, with partial (20%, 30% and 40% by weight) ‎replacement of natural granite aggregate by sintered rice husk ash aggregate; the important physical ‎properties of concrete such as compressive strength and dynamic modulus of elasticity are retained. ‎On other hand the water absorption values within the permissible value for durability considerations.‎

‎ Flexible pavements can be modeled as multilayered elastic systems. Each of the pavement layers ‎can have its own elasticity parameters such as the modulus of elasticity and poison's ratio. The objective ‎of this study is to investigate the effects of variations of modulus of elasticity of each layer on pavement ‎performance or response which reflected as displacement values, also thickness effect of each layer ‎within the system was studied under the dual-tandem axles. KENLAYER program was used to conduct ‎this objective. After running KENLAYER program for fifteen cases that simulates cases for study, it was ‎found that displacement values were decreased when thickness increased, and increased when modulus ‎of elasticity for each layer was decreased.‎

‎ Evaporation equations which are developed and calibrated for one geographical region very often ‎are not valid for different region and different climatic condition. In this paper the Penman original ‎method is modified by using meteorological data from Diwaniya station to calibrate the three equations ‎that were used in Penman's original method, i.e. incoming shortwave radiation equation, net longwave ‎radiation equation, and wind function. Thus, new equations which are applicable to Diwaniya and are ‎different from those originally suggested by Penman for England are presented so that computed ‎evaporation is very close to the observed one.‎

Wave-Net is a promise network which utilizes the wavelet transform in building a new structure of ‎neural network. Training is the major problem facing researchers with the neural networks. In this paper, ‎we use the extended Kalman filter as an efficient tool in training the Wave-Net. The results show that ‎the ability of using extended Kalman filter as training algorithm for wave-net and use it in classification ‎problem and come up with good results especially in reducing the number of iterations in training ‎phase. A comparison between extended Kalman filter and conventional back propagation, which are ‎used in a classification problem, show that the training with Kalman filter is better than training with ‎gradient descent.‎

‎ This research aims to study the water absorption of the hardened high performance concrete (HPC) ‎containing high reactivity metakaolin (HRM) or the rice husk ash (RHA) as a partial replacement 8% by ‎weight of cement . They were added to improve the properties of concrete as a pozzolana.The study also ‎investigates the role of the water reducing superplasticisers in reducing the water absorption .The results of ‎water absorption are expressed in terms of quantity of water absorbed per unit surface area as a function of ‎the elapsed time , also the compressive strength were detected at 7, 28 and 90 days for the purpose of ‎comparison with the changes in water absorption. ‎
‎ The mixes were composed of Ordinary Portland Cement, natural sand, gravel (maximum size 10mm) , ‎the pozzolanic material was mixed as a partial replacement by weight of cement, and the high range water ‎reducing admixture (HRWRA) which was added at the optimum dosage of each mix. ‎
‎ The results show that the high reactivity metakaolin or the rice husk ash effectively decrease the water ‎absorption. Also, when the water reducing admixtures improve the properties of the mixtures, the porosity of ‎the hardened concrete is reduced , consequently the water absorption is reduced significantly. ‎

The present study is mainly concerned with studying the architectural history. It is ‎hypothesized that the equivalent relation between the identity of the historical event ‎and the theoretical knowledge on the basis that both of their reflect the essence of the ‎object. On the contrary of the theoretical knowledge to evaluate that we must know ‎the philosophic and information structures in regard with to know its identity so as to ‎keep it in a good condition. To achieve that, an example is used which includes ‎analytic study about Babylon tower (Ziggurat) since it is destroyed, and has a relation ‎with Babylon from religious and designing point of view. The results give exposure to ‎its identity and basic job clearly. Additionally, it exposes it relation between Babylon ‎and Ziggurat as the research indicated.‎

The aim of this research is to study the effect of the local juss material addition to the ordinary ‎cement mortar which is used in external walls finishing on the performance of its engineering‏ ‏properties ‎like compressive with tensile strength and also its effect on the setting time with its workability. Juss was ‎added to cement mortar and paste with ratios of (20%, 40%, 60%, and 80%) from cement weight to ‎determine its negative effect on their above mentioned properties. Eighty Seven (87) test samples were ‎done,(19) samples for reference juss mortar to find its standard consistency ,hardening time, ‎compressive and tensile strength.(16) samples to find standard consistency for reference cement paste , ‎compressive and tensile strength for reference cement mortar . The rest (52) samples are for the mixed ‎cement mortar and paste with the mentioned juss ratios to know the effect of these additions on their ‎properties by comparing with the reference cement mortar and paste. Results showed decreasing setting ‎time and weak mortar properties with increasing Juss addition and the addition ratio of (40%) is the ‎ratio that decreasing the setting time clearly and the mortar is still have its workability which is ‎disappeared in the higher addition ratios of 60% and 80% and it is not suitable also for the decreasing ‎in compressive and tensile strength.‎

‎ In this work , thermal behavior for composite material consisted from araldite resin(AY103) reinforced ‎by natural palms fibers is studied and compared it with another material reinforced by carbon ‎fibers‏(°0)‏with (1.75g/cm3) density and then these two types of fibers combined together to make a hybrid ‎composite material and also calculated the range of it's thermal conductivity . Fourier equation used to ‎calculate the thermal conductivity coefficient(k) to obtained composite material and as illustrated in ‎diagrams which represent the relation between thermal conductivity coefficient with temperature. The ‎results obtained from thermal conductivity test show that the thermal conducting value at Maximum ‎temperature (60°C) of natural palms fibers( 2.5 W/m.ºC ) higher than reinforcing with carbon fibers ( ‎‎1.49 W/m.ºC ) and hybrid fibers ( 1.91 W/m.ºC ). ‎

‎ This work studies the effect of the addition of glassy sand on swelling properties of bentonite soil. ‎The main objective is to ascertain to what extent the pressure and percentage of swelling will ‎decrease with every percent of added glassy sand . This is done for two cases , the first with zero ‎kn/m2 load , and the second with 50 kn/m2 .‎
‎ The used soil (bentonite ) , and the added material (glassy sand ) , are brought from the ‎Company of Geological Survey and Mining . The rate of additives are 10 , 20 , 30 % of the weight of ‎the dried bentonite soil . ‎
‎ The results of the test of properties of compaction and plasticity showed a marked increase in ‎the values of maximum dry density and a decrease in the optimum moisture content with the ‎increase of additive rate . In the case of plasticity properties , the values of liquid limit, plasticity index ‎decreased in a marked ratios , while the rates of plasticity limit decreased in a very small ratios . with ‎the addition of glassy sand . The results of the test of swelling properties ( rate of the maxium free ‎swelling , swelling pressure ) showed a gradual decrease with the increase of the rate of additive ‎