The current asphalt binder specifications in Libya are based on the Penetration Grade: penetration test is performed at 25°C. Penetration is an empirical measure of the consistency that is used as an empirical indicator of the rutting and fatigue susceptibility of asphalt binder, and is not related to pavement performance. The new mix design methodology developed under the Strategic Highway Research Program (SHRP), called the SUPERPAVE is a performance-based approach. The first step in the implementation of SUPERPAVE methodology is to establish high and low pavement temperatures for a location. The temperatures define the required Performance Grade (PG) of asphalt binder. This paper documents the initial ground work towards implementation of SUPERPAVE mix design for establishing high and low geographical temperature zones. The temperature zoning of Libya was carried out by using temperature data obtained from 8 weather stations. The SHRP and LTPP prediction models were utilized for predicting pavement temperatures. A significant difference was observed between the predicted pavement temperatures from both the models. The SHRP model gives higher, high temperature PG grade providing additional protection against rutting. Since rutting is the most common distress on flexible pavements in Libya , the SHRP models at 50% level of reliability is recommended. The PG of roads that located in Libyan desert are classified to three zones (PG70-10, PG76-10 and PG82-10.PG 76-10 binder seems to be the most common grade that encompasses more than 70% area of Libya desert .However, currently none of the two local refineries produce the bitumen under penetration grade 60-70,that grade equivalent to PG 82-10 binder, thus it should be a concern for highway or the project location. The polymer modified asphalt binder are not produced by Libya refineries.
Asphalt pavements form an integral part of any transportation system. The structural capacity of the hot mix asphalt concrete layers depends on many factors including its temperature. Moreover, temperature can be a major contributor to several types of distresses. Therefore, temperature is a significant factor that affects the performance and life span of a pavement. The Libyan road network expanded at a phenomenal pace from approximately 1500 km of paved roads in 1970 to morethan 100,000 km in 2008. Ghat region is located on the southern east of Libya at latitude (24 59' N) in the desert. With the recent SHRP and LTTP research findings, it was necessary to investigate the applicability of the models developed from these research studies to Ghat's environmental conditions and more generally to the rest of Libyan desert reigions. This paper presents the research undertaken to develop models to predict high and low asphalt pavement temperatures in the Ghat region . A pavement monitoring station was set-up in Ghat to monitor air and pavement temperatures in different depth, wind speed and solar radiation. Data were collected for 365days. Daily minimum and maximum temperatures were recorded. A regression analysis was used to develop the minimum and maximum pavement temperature models, using air temperature, wind speed and solar radiation. This paper presents a new model for predicting maximum and minimum surface pavement temperature based on data collected by installed pavement monitoring station set-up at the Ghat region.
Asphalt pavements form an integral part of any transportation system. The structural capacity of the hot mix asphalt concrete layers depends on many factors including its temperature. Moreover, temperature can be a major contributor to several types of distresses. Therefore, temperature is a significant factor that affects the performance and life span of a pavement. The Libyan road network expanded at a phenomenal pace from approximately 1500 km of paved roads in 1970 to morethan 100,000 km in 2008. Brak region is located on the southern east of Libya at latitude (27°31'N) in the desert. With the recent SHRP and LTTP research findings, it was necessary to investigate the applicability of the models developed from these research studies to Brak's environmental conditions and more generally to the rest of Libyan desert reigions. This paper presents the research undertaken to develop models to predict high and low asphalt pavement temperatures in the Brak region . A pavement monitoring station was set-up in Brak to monitor air and pavement temperatures in different depth, wind speed and solar radiation. Data were collected for 365days. Daily minimum and maximum temperatures were recorded. A regression analysis was used to develop the minimum and maximum pavement temperature models, using air temperature, wind speed and solar radiation. This paper presents a new model for predicting maximum and minimum surface pavement temperature based on data collected by installed pavement monitoring station set-up at the Brak region.
MICROSCOPIC ANALYSIS OF BUILDING MATERIALS HIGH SCHOOL "JOVAN JOVANOVIĆ ZMAJ" NOVI SAD This paperpresents the results ofmicroscopic analysisand chemical composition ofbuilding materials ,ie. bricks andconnectivematerial removedfrom thefacade ofthe high school "Jovan JovanovicZmaj" in Novi Sad.The goal is to, based on the resultsof SEM and EDSanalysisof microscopicimages, as well as onthe basis of photographsmadeIR-camera, and a comparative analysis ofthebrick,which is, for sure, knows that is baked, prove thathigh schoolfacade"Jovan Jovanovic Zmaj" in Novi Sadterracotta. On the basisof chemicalanalysisit can be concludedthat theadditionof ironand aluminumare alsotraces ofmagnesium, titanium andalkali metalsasimpuritysubstances areclay. Inhomogeneous structureis observedin themicrograph sconfirmedth attheceramic substance, typeof bricks andcanonly be used for construction. The presenceof iron oxidessuggests thatthe facade ofthe high school "Jovan Jovanovic Zmaj" in Novi Sad terracotta.
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