scholarly journals Geotechnical Properties of Anthropogenic Soils in Road Engineering

2020 ◽  
Vol 12 (12) ◽  
pp. 4843
Author(s):  
Andrzej Głuchowski ◽  
Katarzyna Gabryś ◽  
Emil Soból ◽  
Raimondas Šadzevičius ◽  
Wojciech Sas
Keyword(s):  
Cyclic Loading ◽  
Bearing Capacity ◽  
Construction Material ◽  
Bottom Ash ◽  
Field Tests ◽  
Recycled Concrete ◽  
Concrete Aggregate ◽  
Test Results ◽  
Anthropogenic Soils ◽  
Road Engineering

The construction of a roads network consumes high amounts of materials. The road materials are required to fulfill high standards like bearing capacity and low settlement susceptibility due to cyclic loading. Therefore, crushed aggregates are the primary subbase construction material. The material-intensity of road engineering leads to depletion of natural resources, and to avoid it, the alternative recycled materials are required to be applied to achieve sustainable development. The anthropogenic soils (AS), which are defined as man-made unbound aggregates, are the response to these requirements. For the successful application of the AS, a series of geotechnical laboratory and field tests were conducted. In this article, we present the set of 58 test results, including California Bearing Ratio (CBR) bearing capacity tests, oedometric tests, and cyclic CBR tests, to characterize the behavior of three AS types and to compare its reaction with natural aggregate (NA). The AS tested in this study are recycled concrete aggregate (RCA), fly ash and bottom ash mix (BS), and blast furnace slag (BFS). The results of the tests show that the AS has similar characteristics to NA, and in some cases, like compression characteristic, RCA and BFS behave a stiffer response to cyclic loading. The test results and analysis presented here extend the knowledge about AS compressibility and AS response to cyclic loading.

scholarly journals Physical, Deformation, and Stiffness Properties of Recycled Concrete Aggregate

2021 ◽  
Vol 13 (8) ◽  
pp. 4245
Author(s):  
Katarzyna Gabryś ◽  
Emil Soból ◽  
Wojciech Sas
Keyword(s):  
Recycled Concrete ◽  
Experimental Program ◽  
Concrete Aggregate ◽  
Test Results ◽  
Recycled Concrete Aggregate ◽  
Granulometric Analysis ◽  
Stiffness Properties ◽  
Grain Distribution ◽  
Natural Aggregates ◽  
Critical Reduction

The construction sector is currently struggling with the reuse of waste originating from the demolition and modernization of buildings and roads. Furthermore, old buildings are gradually being replaced by new structures. This brings a significant increase of concrete debris to waste landfills. To prevent this, many studies on the possibilities of recycling concrete, known as recycled concrete aggregate (RCA), have been done. To broaden the applicability of reused concrete, an understanding of its properties and engineering behavior is required. A difficulty in sustainable, proper management of RCA is the shortage of appropriate test results necessary to assess its utility. For this reason, in the present study, the physical, deformation, and stiffness properties of RCA with gravely grain distribution were analyzed carefully in the geotechnical laboratory. To examine the mentioned properties, an extensive experimental program was planned, which included the following studies: granulometric analysis, Proctor and oedometer tests, as well as resonant column tests. The obtained research results show that RCA has lower values of deformation and stiffness parameters than natural aggregates. However, after applying in oedometer apparatus repetitive cycles of loading/unloading/reloading, some significant improvement in the values of the parameters studied was noticed, most likely due to susceptibility to static compaction. Moreover, some critical reduction in the range of linear response of RCA to dynamic loading was observed.

scholarly journals ANALYSIS OF THE FIELD TESTS RESULTS OF BORED CONICAL PILES UNDER THE ACTION OF VARIOUS TYPES OF LOADS

2018 ◽  
Vol 3 (3) ◽  
pp. 24-29
Author(s):  
Ирина Рыбникова ◽  
Irina Rybnikova ◽  
Александр Рыбников ◽  
Aleksandr Rybnikov
Keyword(s):  
Bearing Capacity ◽  
Load Capacity ◽  
Normal Component ◽  
Cone Angle ◽  
Field Tests ◽  
Side Surface ◽  
Test Results ◽  
Head Diameter ◽  
Cylindrical Piles ◽  
Bored Piles

One of the methods of improving the bearing capacity of bored piles is giving them a taper. The feature of these (wedge-type) piles is that under load they work "as a thrust" and transfer part of the load due to the normal component to the inclined side surface. Three sizes of tapered bored piles were tested, with the length of 4.5 m, head diameter 0.4; 0.5; 0.6 m and with cone angle 1o and 2,5o. The test results were compared with the test results of cylindrical piles, 4.5 m long, with head diameter 0.4 m and 0.6 m. It has been discovered that with the increasing cone angle, the bearing capacity of piles against the pressing load, especially the specific load capacity for 1 m3 of material, as compared to cylindrical piles, increases significantly. It has been determined that the larger is the diameter of the head of the pile, the higher is the bearing capacity against the horizontal load, and the bearing capacity against the pullout load is equal to the breakout force of a pile from the soil.

scholarly journals Application of recycled concrete aggregate in mineral-cement-emulsion mixtures

2018 ◽  
Vol 2018 (11) ◽  
pp. 60-71
Author(s):  
Łukasz Skotnicki ◽  
Jarosław Kuźniewski
Keyword(s):  
Recycled Concrete ◽  
Concrete Aggregate ◽  
Test Results ◽  
Recycled Concrete Aggregate ◽  
Grant Application ◽  
Strength Parameters ◽  
Demolition Waste ◽  
Joint Project ◽  
National Centre ◽  
Research Grant

The article presents selected problems connected with the accomplishment of the research grant ‘Application of reclaimed materials’ as part of the joint project Development of Road Innovations (RID) co-financed by the National Centre of Research and Development as well as the General Directorate for National Roads and Motorways. The main aim of the project was to analyse possibilities of application of reclaimed concrete obtained from the demolition waste from the existing roads to produce new layers of road pavements. The article presents selected test results which show the influence of the reclaimed concrete content on the strength parameters of the MCE mixtures. Significant variation of the tested MCE mixtures properties depending on the percentage of the reclaimed material has been indicated. It has been suggested that new tests should be implemented in the process of MCE mixtures design process. An optimal content of reclaimed concrete has been determined in order to obtain required values of the analysed parameters. The application of reclaimed concrete in conventional MCE mixtures made it possible to achieve positive economical and environmental effects.

scholarly journals The Experimental Study of the Utilization of Recycling Aggregate from the Demolition of Elements of a Reinforced Concrete Hall

2020 ◽  
Vol 12 (12) ◽  
pp. 5182 ◽  
Author(s):  
Katarzyna Kalinowska-Wichrowska ◽  
David Suescum-Morales
Keyword(s):  
Heat Treatment ◽  
Recycled Concrete ◽  
Concrete Aggregate ◽  
Test Results ◽  
Structural Elements ◽  
Mechanical Recycling ◽  
Control Series ◽  
Coarse Aggregates ◽  
Additional Control

The article shows a case study as to whether the thermal and mechanical recycling of concrete is suitable for concrete debris from the demolition of structural elements of a 30-year-old industrial hall. The experiment included 10 series of new composites made from heated recycled concrete aggregate (HRCA) subjected to different variants of heat treatment and one additional control series with only natural aggregate (NA). The compressive strength of the new concretes has been determined. The microscopic observations of HRCA have also been made. The test results revealed that proper heat treatment of concrete rubble makes it possible to obtain a high-quality recycled coarse aggregate, which can be used as a 100% replacement for natural coarse aggregates in new concretes.

Probabilistic Modelling of Strength of Concretes with RCA

2016 ◽  
Vol 722 ◽  
pp. 207-215
Author(s):  
Roman Jaskulski ◽  
Anna Stępień ◽  
Marlena Sobocińska
Keyword(s):  
Tensile Strength ◽  
Recycled Concrete ◽  
Design Parameters ◽  
Concrete Aggregate ◽  
Probabilistic Modelling ◽  
Test Results ◽  
Aggregate Fraction ◽  
Natural Aggregate ◽  
Concrete Mix ◽  
Tensile Splitting Strength

The subject of the work is research and probabilistic modelling of compressive and tensile strength of concrete with recycled concrete aggregate (RCA). Sixteen series of concrete containing natural aggregate and RCA of 50% by mass of coarse aggregate (fraction 4 – 16 mm). Concrete specimens were tested for compressive and tensile splitting strength. In the study also the absorptivity of recycled and natural aggregate was tested, which is the amount of water that both types of aggregates can absorb during concrete mix. Based on the results models were formulated describing the compressive and tensile strength of concrete with RCA. These models are based on the design parameters of the concrete mix. In order to determine the coefficients of the models an estimating of a function of several variables by linear regression was performed. Compliance of the values ​​calculated using the models with the values ​​obtained from the tests was determined by Monte Carlo simulation. The results indicated a possibility of obtaining a high compliance of the test results with results obtained from simulations based on formulated models.

scholarly journals Drying Shrinkage and Rapid Chloride Penetration Resistance of Recycled Aggregate Concretes Using Cement Paste Dissociation Agent

Materials ◽  
2021 ◽  
Vol 14 (6) ◽  
pp. 1478
Author(s):  
Sungchul Yang ◽  
Hyewon Lee
Keyword(s):  
Cement Paste ◽  
Drying Shrinkage ◽  
Experimental Tests ◽  
Preliminary Test ◽  
Chloride Penetration ◽  
Recycled Concrete ◽  
Recycled Aggregate ◽  
Concrete Aggregate ◽  
Test Results ◽  
Durability Test

In the present study, a recycled concrete aggregate (RCA) coating treatment using a cement paste dissociation agent (CPDA) with different mixing methods was newly incorporated in RCA concrete mixtures. First, a preliminary test program was conducted to determine the proper dosage of the CPDA solution throughout its RCA concrete test results from compressive strength, flexural strength, and elastic modulus. Then, a series of experimental tests were carried out to investigate the effect of RCA coating treatment, different mixing method such as the equivalent mortar volume (EMV) method and conventional method, and different RCA replacement ratios on durability test results of RCA concrete such as drying shrinkage values and rapid chloride penetration test (RCPT) values. The test results showed that all RCA concretes mixed with the coated RCAs were found to be workable regardless of different mix methods, with the slump and air contents of all the mixes being almost identical. All the concrete specimens, which were mixed with the coated RCAs with CPDA solution, represented lower drying shrinkage and RCPT values than those mixed without RCA coating treatment, regardless of different mix proportioning methods or RCA replacement ratios. This holds for the concrete specimens proportioned with the EMV method, regardless of different RCA replacement ratios.

scholarly journals DEFORMATION OF CENTRICALLY COMPRESSED REINFORCED CONCRETE COLUMNS WITH ADDITION OF CONCRETE RUBBLE AS COARSE AGGREGATE

2019 ◽  
Vol 4 (5) ◽  
pp. 66-76
Author(s):  
А. Аль-Хаваф ◽  
A. Al'-Havaf ◽  
А. Никулин ◽  
Aleksandr Nikulin
Keyword(s):  
Reinforced Concrete ◽  
Yield Strength ◽  
Bearing Capacity ◽  
Coarse Aggregate ◽  
Experimental Studies ◽  
Green Building ◽  
Concrete Columns ◽  
Recycled Concrete ◽  
Concrete Aggregate ◽  
Reinforced Concrete Columns

The article presents results of experimental studies of centrally compressed reinforced concrete columns with the addition of concrete rubble as coarse aggregate. Previous studies shows that recycled concrete in the form of crushed concrete rubble obtained from construction waste is an environmentally friendly alternative to traditional coarse aggregate for the manufacture of load-bearing structures. Currently, the scientific literature has a limited amount of information about the calculation methods to be used for the design of reinforced concrete columns with the addition of concrete rubble as coarse aggregate. In this paper, the experimental data on the physicomechanical properties of concrete available in the foreign and domestic literature are summarized. In addition, the deformation features of reinforced concrete columns are highlighted to substantiate the initial premises, hypotheses and possible limitations when developing methods for calculating centrally and eccentrically compressed elements from the specified concrete. Researches are analyzed related to the effect of different content of recycled concrete aggregate in the concrete, the number of longitudinal steel reinforcement in the cross section of the element and its yield strength, pitch and yield strength of transverse reinforcement on the deformability and bearing capacity of concrete columns with the addition of coarse aggregate from concrete rubble. The use of such concrete for the manufacture of centrally and eccentrically compressed concrete columns leads to an insignificant decrease in their bearing capacity. This indicates the possibility of recycling a significant amount of concrete rubble resulting from the processing of reinforced concrete structures destroyed during the demolition of buildings; it allows to attribute this technology to “green building”.

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