Applied Mechanics and Materials Vol. 147

Abstract: In this work, a two-dimensional numerical model of heat and mass transfer for the convective drying process of ceramic material was developed. The governing equations of fully coupled non-linear partial differential was derived from the most comprehensive model with considering the heat, moisture and gas transport along with the influence of microscopic pore temperature gradient. Through validation the distribution of the measured variables and coefficients (diffusivity) show a good agreement with the drying stage in porous material.

Abstract: This paper aims to deduce the hydraulics similarity criteria of the anaerobic bio-fluidized bed scale-up design. Based on the flow characteristics of solid, liquid, and gaseous phases in the fluidized bed, the dimensionless analysis has been used to deduce the similarity criteria and discuss how to follow these criteria during designing.

Abstract: Porous concrete dramatically reduces environmental degradation and the negative effects associated with urban sprawl. Porous concrete has been used as an effective method for treating and reducing negative environmental impacts. This paper provides a clear indication of the workability and fresh concrete characteristics in pavement applications. The performance of porous concrete was compared with a concrete sample that is comparable to the material used for the construction of conventional concrete road pavements. The analysis includes the porous concrete mix preparation procedure and the workability tests. The workability tests include the slump, VEBE and compacting factor tests.

Abstract: Among the policies accepted in housing development is forming a large number of cooperative construction companies named Taavoni Maskane Mehr (TMM). Due to lowland type of the grounds some few meters, up to 4m, of compacted backfills are proposed in order to raise the elevation of such areas of such areas. In this research a set of data of compaction and consolidation tests are used for studying the situation in one of these projects named Haftkel project. In this regard the consolidation and settlements due to inundation of area are calculated. The results show that the condition of the project is well enough.

Abstract: In order to analyze dynamic characteristics of steel frame with different pattern braces, three structures with brace of X, V and Λ patterns were designed utilizing STS of PKPM software respectively. Sizes of main members were provided through designed. Based on structural design, time history analysis under different earth waves were made by using ANSYS to investigate the effects exerted from different pattern braces on structural stiffness. Results showed that three different braces played an important role in strengthening structural stiffness. Braces with V and Λ patterns had approximate properties. The story drift ratio and the overall torsion of three different braces met the requirements regulated by Chinese design codes. Conclusions might be useful in practical engineering design during structural system selection.

Abstract: The present research determines the relationships between resonant frequency and some dynamic properties of concrete. Based on the research, new relationship equations are offered. The resonant frequency method is used to measure the resonant frequency of concrete samples from which a dynamic module of elasticity, a dynamic ratio of Poisson, and a dynamic module of shear are computed. Marble or brick waste substituted concrete in samples with water-cement ratios of 0.60 and 0.70 are cured in water and measured at 90 days.

Abstract: Roots of plants stable soils on slope and provide resistance against the forces that improve slope instability. In NW of Iran (East Azerbaijan Province), rangelands was Utilized with animal grazing and changed to agricultural land use; this vegetation is unsuitable vegetation on slope to stable them. We studied Paronychia kurdica Boiss to determine its root biomass characteristics. Data were collected with accidental sampling method (1*1 m) with 10-cm-diameter core in this aria. Minimum, maximum and mean root biomass of this plant is 9.37, 15.70 and 13 gr, respectively.

Abstract: The aim of this study is to identify the risk matrix for factors causing time delay in road construction projects in the West Bank in Palestine from consultants’ viewpoint. Three zones were used in the matrix according to the degree of factors severity on the projects’ time delay; which are: green, yellow, and red. The analysis of 43 factors considered in a survey indicates that 2 factors are located in the green zone, 28 factors are located in the yellow zone, and 13 factors are located in the red zone.

Abstract: As a new type of structural form, the suspend dome structure combines both advantages of the single layer reticulated shell structure and the cable dome structure. The anti-seismic performance of suspend dome have been analyzed by employing a computational model of the Kiewitt suspend dome with 40m span．The different seismic behaviors of time history analysis and response spectrum analysis are analyzed and compared. Some valuable conclusions are drawn for practical design. The results of anti-seismic analysis indicated that the components of the structure were in the elastic period，and had a good anti-seismic performance under 8 degree（0.2g）earthquake.

Abstract: The paper presents a comparative study of particle size analyses of quicklime-stabilized dredged material (LSDM) by combined sieve-hydrometer method (SHM), laser diffraction method (LDM) and sieve method (SM). After analyzed the testing processes and compared the results comprehensively, some conclusions can be conduction. Adopting SHM and LDM to test the particle size of LSDM, not only break the structure unit of soil, but also change its property due to the pure water used as disperser. In addition, the severe flocculation, which attributed to the dissolvable salt in soil introduced by quicklime can’t be drainage effectively, result in the abnormal particle size distribution (PSD) curves produced by the SHM. Therefore, SHM and LDM are not suitable for the particle size analyses of LSDM. SM, without deteriorating the unit structure of aggregates and altering the properties of soil, should be adopted as the most suitable method for LSDM.