Ans :BENKELEAM BEAM METHOD : The Benkelman beam method is less expensive deflection measuring equipment and the method of study is simple and easy to carry out. It consists Datum frame supported on a rear leg with provision for quick adjustment screws , a slender beam of total length 3.66m, hinged to the datum frame at a distance of 2.44 m from the probe end and a clamping arrangement, a dial gauge fitted with extension rods to be in contact with the deflection beam fixed at a distance of 1.22 m from the hinge. The pavement condition survey is carried out before starting the actual deflection measurements. The members of the study team walk along the road stretch, nothing the visual observations on the pavement condition. The points to be noted are 1) Type and extent of cracking 2) Rut depth 3) Type and extent of surface undulations 4) Pot holes. Tests pits are dug at approximately 250 to 500m intervals depending on thee uniformly in performance of pavement structure in order to determine the pavement details such as, thickness and composition of the pavement layers and the type of sub grade below.