research centers


Search results: Found 2

Listing 1 - 2 of 2
Sort by

Article
Improvement of Marshall Properties of the Asphalt Concrete Mixtures Using the Polyethylene as Additive

Author: Lamia A. Ahmed
Journal: Engineering and Technology Journal مجلة الهندسة والتكنولوجيا ISSN: 16816900 24120758 Year: 2007 Volume: 25 Issue: 3 Pages: 383-394
Publisher: University of Technology الجامعة التكنولوجية

Loading...
Loading...
Abstract

In order to increase the durability of highway pavement specific requirementsare needed to control the quality of pavement materials. Therefore, the aim ofthis study is to make and test laboratory specimens in order to characterizeasphalt-polymer and aggregate mixtures by using results from conventionaltest procedures. The research work covers six percentages of polymer contentthose are (2%, 4%, 6%, 8%, 10%, and 12%) percent by weight of asphaltcontent. The polymer modified mixes were designed in accordance withMarshall method and the engineering properties of these mixes weredetermined. The engineering properties of the control and polymer modifiedmixes (stability, flow, bulk density, percent of voids in total mix, and percentof voids filled with asphalt) were evaluated by conventional test (Marshalltest).The test results show that the engineering properties of polymer modifiedmixes meet the requirements of the S.O.R.B. specification for the asphalt mixused in the construction of surface course. The Marshall stability for modifiedmixes is higher than of control mixes.

من اجل زيادة ديمومة الطرق المبلطة ظهرت الحاجة إلى توفر متطلبات خاصة، في هذا البحث،%٦ ،%٤ ،% تم دراسة تأثير إضافة بولي اثلين كبوليمر باستخدام ست نسب من البوليمر ( ٢١٢ %) من وزن الإسفلت .هيئت خلط ات محسنة طبقا لطريقة مارشال وحددت ,%١٠ ،%٨الخصائص الهندسية له ذه الخلطات، إضا فة إلى ذلك قمنابدراسة أداء الخلطات المحسنة .كذلك.هيئت خلطات مرجعية غير محسنة لأجل المقارنة.و قد تم تقيم الخصائص الهندسية للخلطاتالمرجعية والمحسنة والتي تتضمن (ثبات مارشال والكثافة ونسبة الفجوات في الخلطة ونسبةالفجوات المملوءة بالإسفلت . أظهرت النتائج التجريبية إن الخصائص الهندسية للخلطاتالمحسنة تحقق الخصائص المطلوبة من قبل المؤسسة العامة للطرق والجسور للخلطاتالإسفلتية المستخدمة في إنشاء الطبقة السطحية وتحقق زيادة كبيرة في ثبات مارشال .

Keywords


Article
RAINFALL INTENSITY EFFECTS ON Flexible PAVEMENT LAYERS

Authors: lamia A. Ahmed --- Ahmed M.H. Al- Alkadhimi --- Wisam A. Najim
Journal: Journal of Engineering and Sustainable Development مجلة الهندسة والتنمية المستدامة ISSN: 25200917 Year: 2018 Volume: 22 Issue: 4 Pages: 179-191
Publisher: Al-Mustansyriah University الجامعة المستنصرية

Loading...
Loading...
Abstract

The main objective of this work is to study of effect of rainfall intensity on the thickness of pavements layers of flexible pavement structure. This is using Maple 13 software for modeling of this problem and calculation the rainfall intensity and pavement infiltration. It was found that pavement infiltration increases with increasing rainfall intensity because of, the increase in the rainfall intensity caused an increase in the infiltrated water to the base and sub - base layers. Accordingly an increase in pore water pressure resulted which intends cause an increase in porosity and decrease of base and sub - base degree of compaction. Accordingly which leads to increase in time - to- drain, decrease in drainage coefficient for base and sub - base, and subsequently, request to increase their thickness. For flexible pavement, rainfall intensity 256 mm/hr is giving pavement infiltration, thickness and drainage coefficient 3.2m/day, 46 cm, 0.57 respectively and rainfall intensity 25 mm/hr is giving pavement infiltration, thickness and drainage coefficient 0.4 m/day, 18.5cm, 1.7 respectively. Drainage of accumulated water on pavement is accordingly drained rapid in as short time as possible due to minimize potential moisture damage to a pavement structure. It was found that soil type effects of moisture in pavement based on conditions of total saturation with loss of pavement strength from through affect the state of stress through suction (effective porosity) or pore water pressure and affect the structure of the soil through destruction of the cementation between soil particles because of, soil types difference in coefficient of permeability. Where, soil types have been used in this study Well-graded sand, Uniform dense sand and Fine-grain soil.

Listing 1 - 2 of 2
Sort by
Narrow your search

Resource type

article (2)


Language

English (2)


Year
From To Submit

2018 (1)

2007 (1)