CONCRETE PAVEMENT DISTRESSES a) Cracking Cracks in concrete pavements often result from stresses caused by expansion and contraction or warping of the pavement. Overloading, loss of subgrade support, and insufficient and/or improperly cut joints acting singly or in combination are also possible causes. Several different types of cracking can occur: (i) Longitudinal, Transverse, and Diagonal(…)
Transportation
DESIRABLE PROPERTIES OF ASPHALT MIXES FOR PAVEMENTS
Bituminous mixes (some times called asphalt mixes) are used in the surface layer of road and airfield pavements. The mix is composed usually of aggregate and asphalt cements. Some types of bituminous mixes are also used in base coarse. The design of asphalt paving mix, as with the design of other engineering materials is largely(…)
Tunneling Methods
Tunnelling Methods The choice of tunnelling method may be dictated by: • geological and hydrological conditions, • cross-section and length of continuous tunnel, • local experience and time/cost considerations (what is the value of time in the project), • limits of surface disturbance, and many others factors. Tunnel construction methods: • Classical methods • Mechanical(…)
Ground Freezing – Tunneling Methods
Ground Freezing • Ground freezing is a process of making water-bearing strata temporarily impermeable and to increase their compressive and shear strength by transforming joint water into ice. • Freezing is normally used to provide structural underpinning; temporary supports for an excavation or to prevent ground water flow into an excavated area. • Successful freezing(…)
Kansai Airport
Kansai International Airport is an international airport located on an artificial island in the middle of Osaka Bay, off the shore of the cities of Sennan and Izumisano and the town of Tajiri in Osaka Prefecture, Japan. (It should not be confused with Osaka International Airport, which is closer to the city and now handles(…)
PARTIAL-DEPTH REPAIR OF PAVEMENTS
The purpose of partial-depth repairs is to correct localized areas of concrete pavement distress. Repair of this type restores rideability, deters further deterioration, reduces foreign object damage potential, and provides proper edges so that joints can be effectively resealed. Need for Partial-Depth Repair Partial-depth repair is typically used to repair spalling either at pavement joints(…)
CBR METHOD – I R C RECOMMENDATIONS
I R C RECOMMENDATIONS FOR THE CBR METHOD OF DESIGN Some of the important points recommended by IRC for the CBR method of design (IRC:37 – 1970) are given below: The CBR tests should be performed on remoulded soils in the laboratory. In – Site tests are not recommended for design purpose. The specimens should(…)
QUALITY CONTROL OF SOIL STABALIZED PAVEMENTS
Quality control is essential to ensure that the final product will be adequate for its intended use. It must also ensure that the contractor has performed in accordance with the plans and specification, as this is a basis for payment. This section identifies those control factors which are most important in soil stabilization construction with(…)