EXPERIENCE ON DESIGN AND CONSTRUCTION OF ROAD PAVEMENTS USING THE CLAUSES OF EUROPEAN STANDARDS ON HYDRAULICALLY BOUND MATERIALS

2019 ◽  
pp. 42-50
Author(s):  
Tatiana Tereshchenko ◽  
Serhii Illiash
Keyword(s):  
Compressive Strength ◽  
Strength Properties ◽  
Road Pavement ◽  
Rigid Pavements ◽  
State Classification ◽  
Hydraulic Binder ◽  
European Standards ◽  
Pavement Construction ◽  
Design And Construction

Hydraulically bound mixtures (HBM) are most effectively applied in the base layers of flexible road pavements to enhance their load bearing capacity and also in the base layers of rigid road pavements in the case of weak soils of the sub-grade. The evaluation of Ukrainian standards which are identical to European standards relating HBM leads to the point of subsequent implementation of new requirements trough design and construction of motor roads in Ukraine. The by European standards stated requirements and classification of HBM provide a modelling regime closer to the performance of bound pavement layer and give the wider range of HBM designations with different strength properties. Thus, this article reviews such aspects of design and construction of road pavements with HBM layers which are distinguished from the conception approved now in Ukraine. The reviewed clauses on design and construction concern road pavements which, in accordance with the European practice, are classified as flexible pavements or semi-rigid pavements and are comprised of flexible (bitumen-bound) upper layers laid on a HBM base. The reviewed types of road pavement constructions are most eligible to emphasize the possibilities of implementation of new standard requirements in the Ukrainian road building industry. As it was concluded, the European standards state classification of HBM by compressive strength RC and classification by tensile strength in combination with elastic modulus Rt, E. These methods of classification are equivalent with no correlation intended between them and have been successfully used during design and construction of road pavement constructions comprised of bitumen-bound layers laid on a HBM base. When designing the motor roads with the above mentioned pavement construction to be loaded with high traffic, HBM of strength classes RС from С8/10 to С9/12 shall be contributed where classes of strength are determined by the type of a hydraulic binder and can be accorded to the categories by ”Rt, E” values not less than T3 (from T3 to T5). Keywords: hydraulically bound mixtures, classification by values of mechanical properties, compressive strength, base layers from hydraulically bound mixtures.

CLASSIFICATION AND APPLICATION OF SOILS STABILIZED WITH HYDRAULIC BINDER IN ACCORDANCE WITH EUROPEAN STANDARDS

2020 ◽  
pp. 40-48
Author(s):  
Tatiana Tereshchenko ◽  
Serhii Illiash
Keyword(s):  
Compressive Strength ◽  
Building Industry ◽  
Road Building ◽  
Optimum Water Content ◽  
Hydraulic Binder ◽  
European Standards ◽  
Wide Experience ◽  
Optimum Water

Soils being the most widely used materials for road building industry predominantly contribute the improvement of their mechanical and/or technological properties. Relating to the world-wide experience in road building industry, the most effective method for such improvement is treatment of soils with hydraulic binder under optimum water content. Those mixtures being properly compacted set and harden by hydraulic reaction and give stabilized soils. Requirements and classification of hydraulically stabilized soils established by European standards provide wide possibilities for soils application considering their performance in pavement layers. The elaboration of Ukrainian standards identical to the European standards relating hydraulically stabilized soils should permit the elongated life cycle of pavement and also decrease expenses on repairs of road pavements caused by deformation of sub-grade. This article reviews classification and application of hydraulically stabilized soils according to the requirements of European standards. In accordance with European standards, stabilized soils are classified as hydraulically bound mixtures which properties are covered by Specifications on Hydraulically Bound Mixtures (European Standard EN 14227, Part 15). To conform the standard requirements soils should be treated by standard hydraulic binder (or a combination thereof): cement, slag, fly ash, lime, or a standard hydraulic road binder should be applied. Composition and methods of manufacturing (compaction) of specimens of hydraulically stabilized soils give several strength classes of stabilized materials with the highest category characterized by the cubes compressive strength not less than 12 MPa. European standards establish also classification of hydraulically stabilized soils by tensile strength Rt in combination with elastic modulus E; according to that classification the stabilized materials are divided into five categories from T1 to T5. European standards establish also classification of fresh mixtures by immediate bearing index. This value determines the suitability of a compacted layer to support the immediate trafficking. Nevertheless, that requirement may not cover cement-stabilized mixtures for construction of layers which are not intended to be trafficked for 7 days. The in-situ manufacture of stabilized mixtures needs some measures to minimize the inadequacy of properties of a material, or geometry of a layer such as an increased proportion of a binder or an increased layer thickness. Keywords: hydraulically stabilized soils, classification, compressive strength, immediate bearing index, construction of a layer.

Geomaterial classification criteria for design and construction of driven steel H-piles

2020 ◽  
Vol 57 (4) ◽  
pp. 616-621 ◽  
Author(s):  
Pramila Adhikari ◽  
Kam W. Ng ◽  
Yrgalem Z. Gebreslasie ◽  
Shaun S. Wulff ◽  
Todd A. Sullivan
Keyword(s):  
Compressive Strength ◽  
Classification Criteria ◽  
Sample Design ◽  
Hard Rocks ◽  
Design Charts ◽  
Coefficients Of Variation ◽  
Driven Pile ◽  
Pile Resistance ◽  
Design And Construction

Methodologies are proposed to develop criteria for classifying geomaterials into soils, intermediate geomaterials (IGMs), and hard rocks to achieve efficient driven pile designs. IGMs were categorized into IGM-soils and IGM-rocks to reduce the uncertainties in pile resistance estimations associated with properties ranging from soils to rocks. A boundary between soils and IGM-soils was established based upon the performance of two static analysis methods measured in terms of the coefficients of variation between measured and estimated shaft resistances. A boundary between IGM-rocks and hard rocks was established by limiting the geotechnical resistance in IGM-rocks to the compressive strength of a steel pile. Finally, a geomaterial classification flowchart and sample design charts are proposed to facilitate the classification of geomaterials specifically for the design and construction of driven steel H-piles. The proposed framework can be adapted for other driven pile types.

Influencing factors and growth state classification of a natural Metasequoia population

2018 ◽  
Vol 30 (1) ◽  
pp. 337-345 ◽  
Author(s):  
Mu Liu ◽  
Zhongke Feng ◽  
Chenghui Ma ◽  
Liyan Yang
Keyword(s):  
Influencing Factors ◽  
Growth State ◽  
State Classification

Strength Properties of Activated Hwangtoh Mortars

2010 ◽  
Vol 168-170 ◽  
pp. 709-715
Author(s):  
Dongsik Oh ◽  
Doheom Song ◽  
Seongseok Go
Keyword(s):  
Compressive Strength ◽  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Building Materials ◽  
Strength Properties ◽  
Mixing Conditions ◽  
Substitution Ratio ◽  
Pozzolanic Properties ◽  
The Relationship ◽  
Furnace Slag

Hwangtoh (loess) has pozzolanic properties that mean it can be used as a cement admixture when activated at high temperatures, and that it can be used in combination with building materials such as fly ash or blast furnace slag. This study aimed to analyze the relationship between the compressive strength and the brick bond strength of various mortars containing hwangtoh, and also to find the optimum mixing conditions for the use of hwangtoh. It was found that the mortars’ strength properties are significantly influenced by the water/cement ratio W/C and the activated hwangtoh substitution ratio. We recommend the following materials and mixing conditions: W/C 60%, a cement substitution ratio of activated hwangtoh of 20 ~ 25%, and the addition of 10% blast furnace slag to improve the compressive strength of such mortars.

scholarly journals Compressive Strength Properties of Geopolymers from Pond Ash and Possibility of Utilization as Synthetic Basalt

2019 ◽  
Vol 56 (4) ◽  
pp. 365-373
Author(s):  
Byoungkwan Kim ◽  
Bokyeong Lee ◽  
Chul-Min Chon ◽  
Sujeong Lee
Keyword(s):  
Compressive Strength ◽  
Strength Properties ◽  
Pond Ash

scholarly journals POLYMERS AND PLASTIC USE FOR THE HEAT-EXCHANGE EQUIPMENT (REVIEW)

2020 ◽  
pp. 59-71
Author(s):  
I.O. Mikulionok
Keyword(s):  
Heat Exchange ◽  
Heat Exchangers ◽  
Polymeric Materials ◽  
Strength Properties ◽  
Polymers And Plastics ◽  
Heat Exchange Equipment ◽  
Coefficient Of Heat Conductivity ◽  
Exchange Apparatus ◽  
Polymer Type

The possibility of use of the heat-exchangers in whole or in part manufactured with use of polymers and plastics is considered. Despite obvious, at first sight, inexpediency of use of polymeric materials in the heat-exchange equipment (low coefficient of heat conductivity, and also low, in comparison with metals, the strength properties of the majority of the most widespread polymers), «polymeric» heat-exchangers find application in various areas of the industry more and more surely. Classification of heat-exchange apparatuses which constructive elements are executed with use of polymeric materials is proposed. The following signs are the basis for classification: polymer type, a type of polymer meric material, type of the heat-exchange apparatus (a form of heat-exchange elements), reliance on polymeric materials in apparatuses, motion freedom of polymeric heat-exchange elements, level of assembly of a design, and also diameter of tubular elements. Critical analysis the most characteristic designs developed by domestic and foreign designers and inventors is carried out. Ref. 21, Fig. 13.

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