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1

Nadchodzi wiosna...

100%

Rydzik A.

Biuletyn Informacyjno-Handlowy. Ośrodek Doradztwa Rolniczego Boguchwała

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1998

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nr 04

8-9

2

Artykuł dostępny w postaci pełnego tekstu - kliknij by otworzyć plik

Monitoring of pavement state as a basis for economic regulation of greenhouse gases emissions

100%

Radkevich M., Salokhiddinov A.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2014

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tom 46

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nr 2

Road complex which includes a road network with traffic, road services, car repair businesses, and enterprises for the production of fuels and materials for the repair of roads, is an important source of environmental pollution, and the degree of contamination depends on the quality of the road pavement. The present research is aimed to find the interaction between the amount of emissions into the environment from whole road complex and condition of road cover, on creation of a simplified method of determining economic damage from environmental pollution at the road operation and to develop basic mechanism of the economic impact on road services at excess emissions. According to the results of computer experiments mathematical relations of complex road emissions from the evenness of road pavement were obtained. Worked out method of greenhouse (and other) emission inventory permits to determine the total amount of emissions and to identify excess emissions relative to some acceptable level. Definition of economic damage of environmental pollution during road operation can be the basis for determining the amount of ban impositions on road service.

3

Influence of subgrade soil on pavement performance: a case study of Ago-Iwoye-Ilishan road, southwestern Nigeria

84%

Fatoba J. O., Sanni A. O., Ayantunji A. B.

International Letters of Natural Sciences

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2015

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tom 38

Ago-Iwoye –Ilisan road is the major road that links Abeokuta the state capital of Ogun –state to Ijebu towns. The road has always been experiencing pavement failure, which occurs inform of cracks and potholes. Being the major road, the effect of the failure has negative impact on the soicoeconomic growth of Ijebu –areas. The primary objective of the study was to determine the influence of the geotechnical properties of the sub-grade materials on the pavement performance of Ago- Iwoye – Ilishan Road. Eleven (11) soil samples were collected at eight (8) different locations with the aid of hand auger and were air-dried before taken to the laboratory for determination of engineering properties. The Liquid limit and the Plastic limits ranged from 13.9 – 46.2% and 8.1 – 32.7%, with the Plasticity index from 10.6 – 15.9% and Shrinkage limit from 6.2 – 27.7% respectively. The soaked CBR values of the subgrade materials is between 67% and 75% compared with 30% minimum specified by FMWH, 1997. The soils were classified by ASSHTO under the A-6 and A-7 category which shows that the soils are fair to poor as a sub-grade material and USCS classification shows that the soil falls into the SM and SC group. The comparison of all the results with the Nigeria specification (Federal Ministry of Works and Housing general guidelines) for the sub grade materials along the Ago-Iwoye- Ilisian road show that the materials underlain the pavement do satisfy the Nigeria standard. Therefore, the perennial failure frequently experience along the road route is not significantly influenced by subgrade materials. Hence, influence of other factors such as poor drainage courses, level of groundwater table, variation of geologic materials along the road route and poor construction materials should be thoroughly addressed before embarking on future rehabilitation of the highway.

4

Determination of the Resilient modulus MR for the lime stabilized clay obtained from the repeated loading CBR tests

84%

Sas W., Gluchowski A., Szymanski A.

Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

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2012

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tom 44

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nr 2

The main aim of this paper is to prove that CBR repeated test is useful to give an adequate like unconfined cyclic triaxial test parameters for design the pavement and subgrade soils. That parameter is the Resilient modulus (MR) which is the elastic modulus based on the recoverable strain under repeated load. Resilient modulus (MR), is an important parameter which characterizes the subgrade’s ability to withstand repetitive stresses under traffic loadings. The 1993 AASHTO guide for design of flexible pavements recommends the use of MR. The additional aim is connected with the concept of sustainable development. For many countries, where resources are at premium, it is very important that stabilized local soil can be used for road construction. For ensuring that stabilized clay can be used for pavement material standard compaction, CBR and repeated CBR tests were performed. In that paper parameter MR of the subgrade lime stabilized clay soil by laboratory CBR repeated test were determined using for calculation formulas from triaxial cyclic test. Based on AASHTO empirical equation the static CBR values using back analysis was also calculated. Finally both values of CBR determined and calculated were compared.

Ograniczanie wyników

2 Annals of Warsaw University of Life Sciences - SGGW. Land Reclamation

1 Biuletyn Informacyjno-Handlowy. Ośrodek Doradztwa Rolniczego Boguchwała

1 International Letters of Natural Sciences

1 Ayantunji A. B.

1 Fatoba J. O.

1 Gluchowski A.

1 Radkevich M.

1 Rydzik A.

1 Salokhiddinov A.

1 Sanni A. O.

1 Sas W.

1 Szymanski A.

1 2015

1 2014

1 2012

1 1998

Nadchodzi wiosna...

Monitoring of pavement state as a basis for economic regulation of greenhouse gases emissions

Influence of subgrade soil on pavement performance: a case study of Ago-Iwoye-Ilishan road, southwestern Nigeria

Determination of the Resilient modulus MR for the lime stabilized clay obtained from the repeated loading CBR tests