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(…)
Pavement Design
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(…)
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(…)
LOAD-TRANSFER RESTORATION OF PAVEMENTS
New pavement joints typically exhibit good load transfer, particularly if the joints are doweled. However, repeated heavy loads can cause an elongation of the dowel sockets and result in dowel looseness and a reduction of load-transfer efficiency. As load-transfer efficiency decreases, many types of distress rapidly increase, including pumping, spalling, faulting, and slab cracking. Restoration(…)
SUBSEALING JOINTED CONCRETE PAVEMENTS
Purpose of Subsealing The purpose of subsealing is to stabilize the pavement slab by the pressurized injection of a cement grout through holes drilled in the slab. The cement grout will, without raising the slab, fill the voids under it, displace water from the voids, and reduce the damaging pumping action caused by excessive pavement(…)
DISINTEGRATION OF WBM & ASPHALT ROADS
Various Cause of Disintegration of Water Bound Macadam and Surface Treated (Asphalt Roads): 1. Inadequate stability or strength 2. Loss of binding action 3. Loss of base course materials 4. Inadequate Weaving Course 5. Use of inferior materials 6. Lack of lateral confinement for the granular base course. 1. Inadequate Stability or Strength: Poor(…)
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