نشریه آنالیز سازه - زلزله
سال سوم شماره 4 (زمستان 1385)

Coustructing masonry building has been done in a large scale in our country. A ccording to the recorded statistics. It comprises the majority of building in our country. The loss of life and property as the result previous earthquakes reveals that masonry building have not functioned properly. Meanwhile, their complex behaviors resulted from the heterogenons, nonlinear, and plate behavior of its components has brought about their damages in earthquakes, Therefore, ih is assentail to stady these buildings and to persevere the buildings against earthquakes. This paper deals with the assement of the vulnerability of unarmed masonry buildings by the use of building capacity curve representing the resistance. It also concerns eith the way to find mechanical characteristics and shearing resistance curves of strung walls to show the initial step in modeling. The way of constructing a tridimentioal model of these building by using the SAP2000 engineering software would be helpful in understanding their behavior in different froms of stringing Their nalinear statical analysis and the study of analyzed models can help us understsnt the relative morement of stories, the dagree of ductility and the collapse mechanism in the building. One of the results obtained is that the reduction of the dimensions of horizontal strings would results obtained is that the reduction of the dimensions of horizontal strings would reduce the waste of energy and the ductility in coustruction. When the dimensions of the horizontal and vertrical strings are equal and as thick as the Wall strngs, the optimal reative morement and ductility in the buildings are observed. In addition, in buildings with Weak and thinner vertical in the strings with the walls and mostly on the frist storg has happened insuch a way that in some models, strings and walls an the secoud story have not collapsed.

No- fines concrete is a type of concrete from which the aggregate is totally omitted and single- sized coarse aggregates are held together by a binder consisting of paste of hydraulic cement and water. No- Fines concrete creates a porous structural pavement that allows water to infiltrate directly into the soil naturally. Because no- fines concrete allows rainwater to seep directly into the ground, ground water is recharged, water resources are preserved, stormwater runoff is reduced or eliminated, and water quality is improved. This type of concrete is a pervious concrete and can be used successfully for parking lots, sidewalks, low volume streets and various other paving applications. The present paper cites the physical and mechanical behavior of- fines concrete and detailed experiments.

 In recent years, seismic evaluation and vulnerability of the existing buildings, that have been designed based on an earlier seismic design code or designed without seismic design criteria, has been very important. In this paper, the seismic evaluation and vulnerability of concrete buildings, using an old 5- story building with shear walls as an example has been discussed. For this building, Firstly a three- dimensional fully model has been created to simulate the actual nonlinear response of the building due to seismic forces. Then to evaluate the seismic capacity of this building, pushover nonlinear analysis using SAP 2000 as the software has been carried out, based on those given in FEMA- 356. This structure has been evaluated under uniform load and pattern of the first mode in N- S and E- W directions and there has been clarified that there is no capacity of suffering of the predicted performance. Also, based on capacity curves of the structure, it was found that the structural displacement is not enough to carry out the target displacement, and end rotations and shear forces of a lot of beams also the same rotations and axial loads of columns exceed the allowed capacity noted by FEMA- 356. For retrofitting this building, diagonal bracing elements in two directions have been used. Finally the pushover curves after addition of CBF bracing are then compared with pushover curves before addition of bracing form the expected earthquake ground motions and the assessed performances are discussed.

An application of aerated concret (foam concrete) was experimentally studied. In this study the compressive strength of the proposed concrete was measured the effect of parameters such as aggregate size of broken stone, quantity of cement and various densities were exprementally studies, and the best mixture was select.These prepared mixtures are practically useful to optimize the consumption of cement and superior strength in every dry density in nonstructural application.The compressive strength wes varied from 18.19 kg/cm 2 to 97.20 kg/ cm2 for 100 to 1200 kg/ m3 of dry densities during 28 days test. The result of this study showed that the strength capability if proposed mixture increased. The information given in this project can be taken into consider while building nonstructural pieces such as wall blocks and roofs in order to decrease the dead load of building.

According to the experiences gathered from pre- earthquakes & revising the rules of design bylaws the subject of reinforcing the present buildings is important nowadays. This project investigates the usage of quake system on wind- occlusion as one of the most efficient ways of shaking development in small, steel buildiongs.Including important matters in studying the usage of these systems is suitable arrangement determination & wind- occlusion, s mutual relation in frame. This essay reveals the concept of super wind- ocdusions as a contemporary outlook to wind- ocdusion designs & discusses their uses after standard models.This method With the capacity of contemporaneous including of the effect of standard parameters, for determining the primacy of the shaking betterment choices, that its results reveals the efficiency of super wind- occlusions in reinforcing the studing building with the least need to foundation reinforcement.Arrangement determiration & optimal design of wind- occlusions have been accomplished for the advancement of the under- pressure side- component. On the basis of this method, some parameters including, flat escape, slicing of the dynamic pillar & forces vertical to foundation, primary amount & the least dependence of vibrational tides, have been expanded & for their help, the frame’ s unstability effect, change of their joints & of the type with wind- occlusions arrangement in the optimal design of shaking reinforcement have been investigated. High efficiency & great superiority of the persent method on existing methods of optimizing the continuous model with comparing their conclusions in need of roles distribution, the changing capability for practical design & decreasing the wind- occlusions weight along with the importance of super wind- occlusions application have been described in optimal designs of advancement.

The water hammer phenomenon in hydroelectric power plant’s penstock is one of the famous troubles which have been an interest for researchers. Hence this phenomenon can cause many harmful effects on pipe lines and turbine, it is essential that effects of these surges along with line and turbine have been studied and suitable methods for controlling presented. In this way one of the most effective and appropriate methods for surges control, is the use of surge tanks.In this paper as demonstrating the phenomenon and illustrating the governing equations, a computer program developed ‘Visual Basic’ programming language for analyzing the water hammer phenomenon has been presented, which is able to calculate pressure and velocity gradients along with a pipe line ended by a valve and equipped with a surge tank, and also sketch results as diagrams or present as tables.

This pump could be used to irrigate the regions where ground water level is close to land surface and thire is enough wind energy in the region. Since advanced pumps are costly, this pump is designed only to send up water one meter high with the flow of one.Inexperimental Fluid mechanics laboratory of ORRSAY FRANCE amodel of this pump was conducted. Results show that the pump could be manufactured and recommended to farmers.

 The transfer and sedimentation in storage dams reduce the volume and damage the life of water reservoirs. Due to the importance of water, its storage, and the cost time of constructing reservoirs, especially the scarcity of construncting sites for them, a lot of attentions should be given to the sedimentation of dam reservoirs. It requires the estimate of thew sedimentation and its management. Since all suggested techniques to estimate the sedimentation need field operations, time. And hight costs, this paper aims to comine the GSTARS2,1 mathematical model and the ILWIS software to suggest a proper method to estimate the sedimentation, and also to establish a proper date bank in the reservoirs. Miynab dam has been used to study and analyize dare. The resulte Show that we can use this method to estimate the sedimentation of dam reservoirs.

General Kind of encroachment of river is constructing a bridge on it. Purpose of encroachment of river is occupation part of river and flood plain for constructing bridge. Often being economical of bridge innovation affirmated that most of encroachment take place to river and flood plain, which this encroachment can be in form of embankment in flood plain of river or into the main bed of river which cause decreasing of bridge length or appearant in form of bridge piers in main bed of river. In this state, long term or short term reactions of hydraulics, environmental, alluvium, geomorphological and biological aspects are settled in bound of river engineering projects that each of mentioned cases must be analyzed specializely. In this paper used HEC- RAS model for considering and analysis of river changes in hydraulics aspect. HEC-  RAS model simulate the steady flow characteristics only in main direction of flow (1 Dimention). This model have been widely accepted to give satisfactory results for simulation of main characteristics of flow (i. e. depth, velocity, shear stress, …), using field data.This paper considered three different kinds of bridge. 1: natural and exist conditions in river. 2: state which omitted only bridge piers. 3: state which total of bridge (abutment and bridge piers) is omitted. Obtained results showed that in lower descharges, the effect of bridge embankment and bridge piers is low and don’t make problems. For example, in flow rate 28.81 m 83/s, it is seem that insignificant changes in most of hydraulics parameters until 100 meters upstream of the bridge. But in higher and flood descharges, effects of bridge embankment and bridge piers increases, so that, appearance of different dangerous is possible until more distances of bridge. For example, in flow rate 180 m 83/s, changes of hydraulics parameters is seen until 400 meters of upstream of the bridge. Highest of effects intensity is happen in upstream and downstream sections of the bridge (S4 and S5).