scholarly journals Flexural Behavior of Reactive Powder Concrete with Hybrid Section T- Beams

Author(s):  
Rafid Saeed Atea

Abstract Reactive powder concrete (RPC) is unique of the present and greatest significant improvements in constructions field, it has usual excessive kindness happening current duration in the world owing toward its higher concrete properties, great ductility, durability, shrinkage, great opposition to corrosion and abrasion. In this experimental investigation is carried out on the way to revision the RPC flexural activity with Hybrid Segment T- Beams and the mechanical characteristics of this building material. In order to analyze the belongings of steel fiber volumetric ratio, silica fume ratio, tensile steel ratio, hybrid section on RPC T-beam flexural efficiency, the experimental program included testing five beams. The study was focused on determining the load-deflection behavior, letdown mode, strain supply across the depth of the beams and crack pattern at failure. The results of the volumetric ratio of steel fibers and the silica fume ratio were also considered in studying the mechanical properties of RPC mixes. Moreover, a study of hybrid beams showed that use of RPC web and normal concrete in flange efficiently improves the performance of T-beams compared to normal concrete T-beams with a percentage rise of 12 percent and hybrid beams have also shown that the use of RPC flange and normal concrete in web efficiently improves the display of T-beams associated to regular concrete T-beams with percentages increase of 28%.

2020 ◽  
Vol 897 ◽  
pp. 41-48 ◽  
Author(s):  
Munther L. Abdul Hussein ◽  
Sallal R. Abid ◽  
Sajjad H. Ali

An experimental program was directed in this study to evaluate the abrasion resistance of reactive powder concrete (RPC) under direct normal impact of water jet. Abrasion and compressive strength specimens were cast from six RPC mixtures using different single and hybrid distributions of 6 mm-length and 15 mm-length micros-steel fibers and 18 mm-length polypropylene fiber. Fixed mix proportions were used for the six RPC mixtures and with fixed total volumetric fiber content of 2.5%. In addition to the RPC mixtures, a normal concrete mixture was prepared for comparison purposes. All specimens were cured in the same conditions and tested at an age of 28 days. The test results showed that abrasion weight losses increase with time at rates that are independent of fiber type and fiber distribution. The results also showed that all RPC mixtures exhibited significantly lower abrasion losses than normal concrete. The lowest percentage abrasion weight losses were recorded for the mixture with pure 15 mm micro-steel, where after 12 testing hours, it was 0.41% of the total weight before testing. On the other hand, the mixture with pure 6 mm micro-steel fiber exhibited the highest percentage abrasion weight loss (0.98%) among the six RPC mixtures. Another conclusion is that the inclusion of polypropylene fiber to compose hybrid fiber distribution with micro-steel fiber led mostly to lower abrasion losses.


2018 ◽  
Vol 24 (7) ◽  
pp. 75
Author(s):  
Mohammed Mosleh Salman ◽  
Husain Khalaf Jarallah ◽  
Raed Satar Al-Behadili

In this research, the structural behavior of reinforced concrete columns made of normal and hybrid reactive powder concrete (hybrid by steel and polypropylene fibers) subjected to chloride salts with concentration was 8341.6 mg/l. The study consists of two parts, the first one is experimental study and the second one is theoretical analysis.  Three main variables were adopted in the experimental program; concrete type, curing type and loading arrangement. Twenty (120x120x1200) mm columns were cast and tested depending on these variables. The samples were reinforced using two different bars; Ø8 for ties and Ø12 with minimum longitudinal reinforcement (0.01Ag). The specimens were divided into two main groups based on curing type: The first group consists of casting and testing of ten columns that cured in tap water for 28 days with two types of concrete (normal and hybrid), five columns for each type. While the second group consists of ten columns that direct cured and fully immersed in chloride water (8341.6 mg/l) 6 months with two types of concrete (normal and hybrid), five columns for each type. The specimens were tested under three types of loading, the first one is axial load, the second one is eccentric load with three different eccentricities (50,100 and 150) mm and where (e/h) are (0.42, 0.83 and 1.25) respectively from the center of column while the third type of loading is tested the specimens as beam. The experimental results showed an increase in ultimate load capacity and higher chlorides resisting for hybrid reactive powder concrete in comparison with normal concrete in both types of curing (tap and chloride water) through studying strain profile. Interaction diagram charts were obtained from different types of loading for each specimen. These charts showed high values for hybrid reactive powder concrete in comparison with normal concrete.  


2018 ◽  
Vol 25 (3) ◽  
pp. 30-39
Author(s):  
Husain Khalaf Jarallah ◽  
Nidaa Qassim Jassim

In this investigation the effect of large web opening on the on the behaver of beams made by normal concrete (NC) and reactive powder concrete (RPC) have been studied. The experimental work consists of casting and testing in flexure 12 rectangular simply supported reinforced concrete beams. The main parameters of this test are opening locations and normal concrete and RPC location with is the section. The ultimate loads, cracking loads, load -deflection behavior, skew of the openings (deflection at the two opposite corners of openings) and ductility were discussed. These results showed that increase ultimate loads (Pu) and stiffness by increase RPC layers. The using RPC layers increase ultimate load about (1-30) %. Using RPC in compression fiber is found to be more effective than using RPC in tension fiber. The cracking load of hybrid beam with one layer of RPC in compression fiber (having one opening) higher than NC beams by 48.5%. The ultimate strength was decreases with increases opening about (4-21)%, thus indicating that the stiffness decreases accordingly. Hybrid beams with RPC in tension fiber failed with less crack than those for hybrid beams with RPC in compression fiber at the same number of openings. The skew at opening of flexural zone show greater values than the skew at opening in shear zone for each beam until failure. The increase in the number of openings leads to increase in the ductility because it reduces the strength of beams.


Teras Jurnal ◽  
2017 ◽  
Vol 3 (2) ◽  
pp. 157
Author(s):  
Yulius Rief Alkhaly

<p>Reactive powder concrete (RPC) merupakan varian baru dari beton mutu ultra tingggi (ultra high strength concrete) yang diperkenalkan kepada umum pertama kali pada tahun 1994. Beton modern ini memiliki beberapa keunggulan dibandingkan beton konvensional (normal concrete) atau beton kinerja tinggi (high performance concretes). Penelitian tentang RPC di Indonesi masih sangat terbatas, RPC pertama bermaterial lokal Indonesia dikembangkan tahun 2009, dengan sumber silika berasal dari silica fume. Sebagai bagian dari berbagai penelitian lanjutan tentang RPC, hasil akhir dari riset ini diharapkan dapat menghasilkan RPC yang benar-benar sesuai dengan karakteristik material di Indonesia. Sumber silika yang digunakan berasal dari limbah bahan organik sehingga dapat menekan biaya produksi dan menghasilan green concrete yang dapat mengurangi dampak negatif limbah terhadap lingkungan.</p><p><strong>Kata kunci:</strong> Reactive Powder Concrete, Silika, Limbah Bahan Organik</p>


2019 ◽  
Vol 13 (1) ◽  
pp. 260-270
Author(s):  
Yaarub G. Abtan ◽  
Hassan Falah Hassan

Background: Over the last three decades, the interest in using advanced high-performance materials in the construction industry has been increasing worldwide. Recently, a very high strength cement-based composite with high ductility called Reactive Powder Concrete (RPC) has been developed. The RPC concept is based on the principle that a material with a minimum of defects such as micro-cracks and voids will be able to achieve greater load-carrying capacity and durability. Methods: In the present paper, an experimental program of sixteen reinforced concrete one-way slabs was conducted to investigate their behavior under flexural loading. Four of these slabs were with Normal Concrete (NC) and the others of Modified Reactive Powder Concrete (MRPC). All slabs were identical in the dimension of its length and width (1000×500) mm, respectively, and its thickness was varied as one of the variables used in the present work. Other parameters for a one-way slab are concrete type, steel fibers content and flexural steel reinforcement ratio (0.33 and 0.66)%. Results: The results showed that the MRPC slabs with steel fibers failed in a ductile manner and had ultimate load capacity more than that of non-fibrous MRPC with an improvement percentage that reaches up to (66) %. This percentage became (212) % in comparison with normal concrete slabs. Conclusions: Moreover, the results showed that slabs, for both concrete types, reinforced with lower steel ratio failed by tension mode, otherwise, the slabs of higher reinforcement steel ratio failed by combined tension-shear mode. However, an improvement was observed in the ultimate load capacity up to (53 and 98) % when the ratio of steel reinforcement and slab thickness increased, respectively.


2019 ◽  
Vol 9 (12) ◽  
pp. 2456 ◽  
Author(s):  
Mathias Flansbjer ◽  
Natalie Williams Portal ◽  
Daniel Vennetti

As a part of the SESBE (Smart Elements for Sustainable Building Envelopes) project, non-load bearing sandwich elements were developed with Textile Reinforced Reactive Powder Concrete (TRRPC) for outer and inner facings, Foam Concrete (FC) for the insulating core and Glass Fiber Reinforced Polymer (GFRP) continuous connectors. The structural performance of the developed elements was verified at various levels by means of a thorough experimental program coupled with numerical analysis. Experiments were conducted on individual materials (i.e., tensile and compressive tests), composites (i.e., uniaxial tensile, flexural and pull-out tests), as well as components (i.e., local anchorage failure, shear, flexural and wind loading tests). The experimentally yielded material properties were used as input for the developed models to verify the findings of various component tests and to allow for further material development. In this paper, the component tests related to local anchorage failure and wind loading are presented and coupled to a structural model of the sandwich element. The validated structural model provided a greater understanding of the physical mechanisms governing the element’s structural behavior and its structural performance under various dead and wind load cases. Lastly, the performance of the sandwich elements, in terms of composite action, was shown to be greatly correlated to the properties of the GFRP connectors, such as stiffness and strength.


2012 ◽  
Vol 174-177 ◽  
pp. 1090-1095 ◽  
Author(s):  
Kai Pei Tian ◽  
Yang Ju ◽  
Hong Bin Liu ◽  
Jin Hui Liu ◽  
Li Wang ◽  
...  

The explosive spalling of high-strength concrete due to fire is a problem that has garnered increasingly widespread attention, particularly the explosive spalling of reactive powder concrete (RPC). For years, based on the vapor pressure mechanism, the addition of fibers has been demonstrated to be somewhat effective in protecting against spalling. However, relevant experiments indicate that fibers are not effective for dense concrete, which is a challenge for the simple vapor pressure mechanism in providing spalling resistance for RPC. The authors found that silica fume plays an important role in the explosive spalling of RPC. Thus, four classes of RPCs with different ratios of silica fume were prepared, and the spalling phenomena and the inner temperature distribution during heating were investigated. The results show that silica fume content has a prominent effect on the spalling process of RPC.


2018 ◽  
Vol 162 ◽  
pp. 02014
Author(s):  
Mazin Abdulrahman ◽  
Alyaa Al-Attar ◽  
Marwa Ahmad

Reactive Powder Concrete (RPC) is an ultra-high performance concrete which has superior mechanical and physical properties, and composed of cement and very fine powders such as quartz sand and silica fume with very low water/ binder ratio and Superplasticizer. Heat treatment is a well-known method that can further improve the performance of (RPC). The current research including an experimental study of the effect of different curing conditions on mechanical properties of reactive powder concrete (compressive strength, modulus of rupture and splitting tensile strength), the curing conditions includes three type of curing; immersion in water at temperature of 35 OC (which is considered as the reference-curing situation), immersion in water at temperature of 90 OC for 5 hours daily and curing with hot steam for 5 hours daily) until 28 days according to ASTM C684-99 [8]. This research includes also the study of effect of adding silica fume as percentage of cement weight on mechanical properties of reactive powder concrete for different percentage ratios (5%,10% and 15%). Super plasticizer is also used with ratio of (1.8%) by weight of cementitious material; constant water cement ratio (0.24) was used for all mixes. For each reactive concrete mix, it has been cast into a cubes of (150*150*150) (to conduct the compression test), a cylinders of 150mm diameter with 300mm height (to conduct split test) and prisms of (500*100*100)mm to conduct the modulus of rupture test. The results showed that the best method of curing (according to its enhancing the RPC mechanical properties) is the method of immersion in hot water at temperature 90 OC for the all silica fume percentages, and the best used silica fume percentage was (10%) for the all used curing methods.


Sign in / Sign up

Export Citation Format

Share Document