Design, Implementation and Evaluation of Roller Concrete Pavements to Prevent and Reducesing the Breakdowns
Case Study: Using RCC in the Domestic Roads of the PREFAB Company
Saeed
Zolghadri
C.E.O
author
Vahid
Gholizade
Technical Consultant
author
Ali Akbar
Maghsodi
Chief Technical Consultant
author
text
article
2017
per
Roller concrete is a type of concrete with slump is almost zero. Concrete concrete is a concave concrete roller whose resistance to its formation is similar to that of poured soil. The amount of moisture should be adjusted in such a way that, while providing the mixing conditions and the density of the concrete, the cement paste is uniformly spread in concrete and the concrete is subjected to the weight of the roller. Following the successful use of roller concrete in dam construction, the features and benefits of this type of concrete, including the ability to obtain high resistance at low ages and the need for arms, molding and payment, which facilitates and accelerates the implementation of the work, The use of this type of concrete in the pavement was encouraged. The use of commonly used equipment for the implementation of asphalt pavements to implement roller concrete concretes along with lower maintenance costs and longer shelf life has been instrumental in expanding the use of this type of concrete as pavement pavement. In our country, due to the increasing capacity of cement production to meet the needs of domestic civil engineering projects and the demand for export markets, the expansion of the use of concrete procedures on the roads as a practical way to create a sustainable consumption market for a part of the production of cement is posing. . In this paper, some laboratory experiments and achievements in the use of roller concrete as a pavement on the inner streets of the refinery, including the design of mixed designs using native materials and part of the stone waste materials, measures to improve the production line of materials Stone and Concrete Plant Factory To comply with the requirements for the construction and carrying of concrete rollers, considerations about the operation of conventional machinery for road construction for the implementation of roller concrete and the processing and maintenance of roller concrete in hot weather are detailed.
Journal of Concrete Structures and Materials
Iranian Concrete Society
2538-5828
2
v.
1
no.
2017
5
24
https://www.jcsm.ir/article_54793_eb6b8455d110dead2c614116fdc3288a.pdf
dx.doi.org/10.30478/jcsm.2017.54793
Thermal behavior of flexural specimens strengthened with various adhesives and FRPs
Ali
Sadrmomtazi
Associate Professor of Civil Engineering Department, University of Guilan
author
Hamidreza
Kramati
M.Sc in structural of Civil Engineering, University Campus, University of Guilan
author
Behzad
Tahmouresi
M.sc in structural engineering,university of guilan
author
text
article
2017
per
The use of fiber reinforced polymer (FRP) composites is ever growing in the construction industry. High strength- weight ratio, corrosion resistance and suitable durability are the main criteria for FRP selection and design. However, in case of high temperature exposure, change in the material properties affects the overall structure performance. The aim of this study is to evaluation the effect of cement and epoxy adhesives on the thermal performance of concrete flexural specimens strengthened with basalt (BFRP) and glass (GFRP) fabrics. Therefore, 105 flexural specimens (100 × 100 × 500 mm) were made by a constant water-cement ratio; and were kept under the 50°, 100° and 200°, for a period of one and three hours, respectively. The results show that increasing the temperature led to decreased flexural strength of unreinforced specimens by 48%. Also, flexural strength of cement and epoxy adhesives impregnated specimens decreased up to 47% and 60% respectively. Results from the presented model shows at temperatures lower than 100 0C, flexural strength of cement adhesive impregnated specimens was lower than epoxy adhesive impregnated specimens; but at 200 0C, flexural strength of specimens strengthened with basalt and glass fabrics increases 1.3 and 1.15, respectively. Also, curve for flexural strength of specimens strengthened with basalt fabrics compared to glass fabrics had an ascending trend, while it had a descending trend for epoxy adhesive impregnated specimens.
Journal of Concrete Structures and Materials
Iranian Concrete Society
2538-5828
2
v.
1
no.
2017
25
36
https://www.jcsm.ir/article_54795_88191a844e4f8a6db459f980d84a4dd0.pdf
dx.doi.org/10.30478/jcsm.2017.54795
Investigation of cracking moment in RC beams with FRP bars
Fahimeh
Maleki
MSc, Department of Civil Engineering, Semnan University, Semnan, Iran.
author
Ali
Kheyroddin
Professor, Faculty of Civil Engineering, Semnan University
author
text
article
2017
per
In this paper, has been studied the effect of using FRP bars on the cracking of reinforced concrete (RC) beams. Due to the corrosion of steel bars in the certain condition, the use of FRP bars has been widely considered in recent years. In order to investigate the cracking behavior, fifteen RC beams with steel bars and glass fiber reinforced polymer (GFRP) with different reinforcement ratio were analyzed in ABAQUS software. the experimental results of Al-Sunna et al. have been used For validation, that specimen beam has 2550 mm length with rectangular cross section of 250 × 150 mm. The simulation results showed that the use of GFRP bars due to its linear elastic behavior reduces cracking moment and in RC beams with GFRP bars with increasing concrete cover, cracking moment decrease about 1% -5%. In RC beams with GFRP rebars, the increase in the number of bars layer with a constant reinforcement ratio, cacking moment reduces about 1%- 5% and with concrete strength increase that cracking moment increasing about 15% to 25%.
Journal of Concrete Structures and Materials
Iranian Concrete Society
2538-5828
2
v.
1
no.
2017
37
47
https://www.jcsm.ir/article_54798_bb7753a3c59d601a9921d9badac01f42.pdf
dx.doi.org/10.30478/jcsm.2017.54798
Effects of Micro Silica on Mechanical Properties of Roller Compacted Concrete Pavement (RCCP) in Cold Regions
Hooman
Pourabdollah
Department of Road and Transportation, Ahar Branch, Islamic Azad University, Ahar, Iran.
author
Rouzbeh
Dabiri
Department of Civil Engineering, Tabriz Branch, Islamic Azad University, Tabriz, Iran.
author
text
article
2017
per
Nowadays with development in transportation networks, majority of countries revenue is spent on maintenance and preservation. One of the pavements is Roller Compacted Concrete (RCC) that is most economical and durable type of pavements. As regard most of RCC pavements subjected to weather conditions especially humidity, freezing and loading due to traffic gradually have become destroyed. Therefore, durable of RCC against thaw and freezing cycles and suitable time for transport and operation is very important. Main purpose of this research is evaluation of micro silica effects on mechanical properties of RCC in cold regions. For this target, material with 5, 10, 15, 20 and 25 percent micro silica mixed and 2% aerosol matter added. Mechanical properties of mixed materials with using compression, indirect tensile strength, thaw and freezing cyclic, water absorbing, density, vebe and specific gravity tests evaluated. Generally, results of tests showed that with adding 10% micro silica in RCC performance get better.
Journal of Concrete Structures and Materials
Iranian Concrete Society
2538-5828
2
v.
1
no.
2017
48
64
https://www.jcsm.ir/article_54799_58622f6ab63ac96c0128a9da87b1adc5.pdf
dx.doi.org/10.30478/jcsm.2017.54799
Experimental study on the influence of the shape, size and type of cement on the compressive strength of concrete specimens
Baitollah
Badarloo
Structure, Faculty of Engineering and Technology, Qom University of Technology, Qom, Iran
author
text
article
2017
per
Compressive strength test of concrete is one of the most important tests to control the quality of concrete in construction structures and based on the workshop conditions and rules of the relevant regulation and standards, the control specimens with different dimensions and shapes (cubic and cylindrical) are used. In this research for concrete grade C25 and using different types of cement, variations the conversion factors for strength of specimens with different shapes and dimensions was experimentally investigated. In this research with use the cement types 1-425, 2 and 5, totally 81 cubic and cylindrical concrete specimens with different size and dimensions (200×200×200) mm, (150×150×150) mm and (150×300mm) were made and tested at ages 3, 7 and 28 days. The result of this study show that in addition to the shape and size of the specimens, the type of cement used also affect the strength and conversion factor of the strength of the specimens with different shapes and sizes.
Journal of Concrete Structures and Materials
Iranian Concrete Society
2538-5828
2
v.
1
no.
2017
65
76
https://www.jcsm.ir/article_54800_fbdfa3330243baf2b4901099bda4bbb3.pdf
dx.doi.org/10.30478/jcsm.2017.54800
Evaluation of Seismic Resilience of Urban Infrastructure
Negar
Rajabpour
M.Sc. Student, Faculty of Civil Engineering, Semnan University, Semnan, Iran
author
Hosein
Naderpour
Associate Professor, Faculty of Civil Engineering, Semnan University, Semnan, Iran
author
Pouyan
Fakharian
Ph.D. Candidate, Faculty of Civil Engineering, Semnan University, Semnan, Iran
author
text
article
2017
per
In order to overcome the negative effects of the disasters, buildings, infrastructures and more generally, communities, are better to react resiliently. As an illustration of the concept of resilience, seismic resilience is referred to as the ability of a system to reduce the chance of a shock, to absorb such a shock and to recover the system after the disaster as soon as possible. The resilience of structures has gained its initial approach from a more general and broader definition, and due to that, further engineering concepts have been formulated. Physical quantification of the resilience involves the probability of exceedance of the floor acceleration or drift from a certain limit. For this purpose, nonlinear response of the structures as well as the effect of rehabilitation, repair and recovery time of the structure, and following to that communities, are used. This proposed framework relates the probability function, failure and resilience as a continuous approach. In this paper, we try to introduce a characteristic called the communities resilience index, by which the performance of various communities is calculated and compared by the PEOPLES framework.
Journal of Concrete Structures and Materials
Iranian Concrete Society
2538-5828
2
v.
1
no.
2017
77
87
https://www.jcsm.ir/article_54801_fb934a88076ed5e406e58375b232659f.pdf
dx.doi.org/10.30478/jcsm.2017.54801
Effect of entrapped air on strength and durability of the concrete containing of chemical and natural admixtures
Omid
Behnami
Department of Civil Engineering, Qazvin Branch, Islamic Azad University, Qazvin, Iran.
author
Reza
Farokhzad
Department of Civil Engineering, Qazvin Branch, Islamic Azad University, Qazvin, Iran.
author
text
article
2017
per
In order to use concrete as a building material with multiple applications, its mechanical and durability properties should be considered. Mechanical properties include compressive, tensile, flexural, and abrasive strength. And, the durability property, here, is defined as the resistance to sulfates and chlorides attacks. For all these situations, concrete porosity relates to the mechanical strengths and durability resistance in a specific way. In this study, these relations as well as the effect of chemical and natural additives; including Zeolite, Meta Kaolin, Micro Silica, and Plasticizers with different percentages; are investigated. To do this, specimens are compared in terms of temperature, concrete slump, porosity, permeability, electrical resistivity, water absorption, and compressive strengths of 7, 28, and 90 days. Results showed low levels of porosity for concretes with Micro Silica and Zeolite, respectively, high water absorptions for those with Meta Kaolin and Zeolite, respectively, and low levels of permeability for those of Micro Silica and Meta Kaolin, respectively. High electrical resistivity is found for the samples containing Meta Kaolin and Zeolite, after 7 and 28 days, and for the samples containing Zeolite and Micro Silica, after 90 days. Concrete samples containing Micro Silica and Meta Kaolin showed high levels of compressive strength. In this regard, although, Zeolite-concrete mixture had showed low level of compressive strength after 7 days, it was improved after more days. It is also concluded that a mixture of concrete with Micro Silica and 1.5% of plasticizer has the lowest level of porosity and the highest level of compressive strength. All these proved that, generally, reducing porosity improves mechanical and durability properties of concrete.
Journal of Concrete Structures and Materials
Iranian Concrete Society
2538-5828
2
v.
1
no.
2017
88
109
https://www.jcsm.ir/article_54802_2dc9cfc1934732cb16bcba9254a1e383.pdf
dx.doi.org/10.30478/jcsm.2017.54802
Modeling and Studying the Behavior of Reinforced Concrete Infilled Frames with Reinforced Polymer Composites
Fariborz
Nateghi Elahi
Professor, International Institute of Earthquake Engineering and Seismology (IIEES), Tehran
author
Ayoub
Dehghani
Instructor, Dep. Of Civil Engineering, Persian Gulf University, Bushehr
author
Mohammad Javad
Alinejad
Civil Engineering, Islamic Azad University, Kangan Branch
author
text
article
2017
per
There are many concrete infilled frames in Iran, that they need to strengthen . One of the effective methods to strengthen for these buildings, that in recent years many studies have been done about it, is the use of fiber-reinforced composites (FRP). In this paper, we provide a simple method to estimate the stiffness and ultimate load capacity of concrete infilled frame. Infill materials modeled via equivalent diagonal element, are modeled and compared with each other. The two methods can be easily applied to the two-dimensional nonlinear analysis of structures. The result of pushover analysis, offer us a model that is the very close and similar to the prototype. In addition, we provide the results of a case study on a five-story concrete infilled frame with FRP composites have been strengthened, that can be used as a way to replace Infill FRP composites in frames. The laboratory and analytical results that obtained, indicate that the reinforced concrete infilled frame with reinforced FRP composites, increases stiffness and final load capacity of the structure.
Journal of Concrete Structures and Materials
Iranian Concrete Society
2538-5828
2
v.
1
no.
2017
110
125
https://www.jcsm.ir/article_54803_d62f5c3d215dc53934e409db581c8460.pdf
dx.doi.org/10.30478/jcsm.2017.54803