فهرست مطالب

Advance Researches in Civil Engineering - Volume:1 Issue:2, 2019
  • Volume:1 Issue:2, 2019
  • تاریخ انتشار: 1398/01/22
  • تعداد عناوین: 6
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  • Abdollah Mortezaei, Seyyed Vahid Razavi Tosee Pages 1-7

    In this experimental study, the mechanical strength properties of concrete using 5, 8 and 12% of organic waste ash (OWA) instead of cement are investigated. The results showed that the 28 days compressive and tensile strength and slump of the concrete made by OWA in compared with ordinary concrete were 0.99, 0.99, and 0.8, respectively, for 5% OWA instead of cement, 0.96, 0.9, and 0.69, respectively, for 8% OWA instead of cement, and 0.9, 0.9, and 0.09, respectively, for 12% OWA instead of cement.

    Keywords: Concrete, OWA, Mechanical strength, Cement
  • Ali Akbar Karimzadeh, Fardin Jafarzadeh, Adel Ahmadinezhad Pages 8-15

    Shear modulus and confined modulus are important parameters for static and dynamic analysis in geotechnical applications. Cyclic simple shear apparatus had been developed by mounting bender element and ultrasonic sensors to measure continuous shear wave and pressure wave velocities for determination of Gmax and M. For this purpose two new pedestals have been fabricated on which HAE ceramic disc and sensors were mounted. A pressure control panel and a hanging column system have been designed to apply high and low matric suction values with high accuracy. Finally, some tests was conducted to verify the result of device performance and to compare with the theoretical results of unsaturated soils.

    Keywords: Dynamic Simple Shear Apparatus, Bender Element, Ultrasonic, Unsaturated soils, Maximum shear modulus
  • Hadi Abioghli, Amir Hamidi Pages 16-21

    In this research, a model for prediction of mechanical behaviour of fiber-reinforced cemented sands is presented. For this purpose, at first a general plasticity constitutive model for sand soils is selected and the parameters of this model are determined for three samples of triaxial experiments done on different soils. Then it is developed with generalization of existing model based on parameters of fiber-reinforced cemented sands. Through modelling steps, elastic parameters, flow rule and hardening law of base model for fiber-reinforced cemented soils are modified. For evaluating the developed model, the results are compared with results of three samples of triaxial experiments done on fiber-reinforced cemented sands. Finally, the developed model efficiency is confirmed at different confining pressures with different percent of cement and fiber.

    Keywords: Fiber-reinforced cemented sands, Constitutive modelling, Axial strain, Deviatoric stress
  • Seyyed Farhad Mirfakhraei, Gholamreza Andalib, Ricky Chan Pages 22-41

    In this paper a numerical investigation of installation of actuator in a toggle configuration for decreasing of active control forces in engineering structures has been carried out. During the past two decades, researchers have been focused to prevent the vibration of tall building from strong earthquakes. For achieving this purpose, they applied either massive conventional bracing or passive energy dissipation dampers. Subsequently, they developed active control systems in structures to resist against the high seismic loads. However, this later method eventuates installing massive actuators in building which are not only very costly and uneconomically but also needs large electricity power. In this research, using by known earthquakes, investigation of the effects of the toggle configuration on actuator forces has been performed numerically. For numerical investigation, active tendon control system was selected as a comparison. The numerical investigation shows significant reduction in actuator forces through using toggle configuration. Finally, comparing results through the numerical processe express high matching that relies on mitigation of control forces in the toggled active model.

    Keywords: Active control system, Control forces, Structural active vibration control
  • Fariborz Mohammadi Tehrani, Farhad Tizhoosh, Seyyed Mahdi Mousavi, Ali Kavand Pages 42-47

    This paper presents the result of an experimental investigation on a full-scale reinforced lightweight aggregate embankment. The reinforced body was expanded clay aggregates, reinforced with geotextile facing. Loadings included self-weight, static surcharge applied using concrete slabs on top of the embankment, and dynamic loads simulated by a vibrator on top of the concrete slabs as well as dropping weight impacts. The system was designed using load and resistance factor design. Measured parameters included lateral and vertical deformations, velocity, and acceleration during tests. This paper covers design and construction details of the built embankment. Results indicate viability of using lightweight expanded clay aggregate in the proposed mechanically stabilized earth walls with geotextile facing as a mean for accelerated construction of bridge abutments.

    Keywords: Embankment, Mechanically Stabilized Walls, Lightweight Expanded Clay Aggregates, Geotextile
  • Mahnam Roohi Hir, Michael Yousefadeh, Rouzbeh Dabiri Pages 48-55

    Collapsible soils is one of the problematic soil because of complex mechanism collapse in them, the recognizing and analyzing effective parameters on phenomenon is so important. Collapsible soil is non- saturate soil, due to moisten and specifically loading, connection between soil particles become loose and finally suddenly destroying happen in soil layer. In this study, collapsible potential in soil layers of Hir city based on practical methods were evaluated. 16 specimens were collected in study area. Practical methods were divided to qualitative and quantitative criterions. In quantitative procedure, double odeometer test based on ASTM were performed. Results of this study showed that between qualitative methods there is not good agreement. Although, quantitative procedure proposed high risk in terms of collapsibility in soil layer.