The compressive strength of concrete cylinders

APPARATUS

Compression testing machine, cylinder mould of 150mm diameter and 300mm height, weighing balance.

PROCEDURE

(i) Cast the cylinder and cure for 28 days.

(ii) Takeout the specimen from the curing tank.

(iii) Wipe out the excess water from the surface of specimen.

(iv) Place the specimen vertically on the platform of compression testing machine.

(v) Apply the load continuously and uniformly without shock at the rate of 315 kn/min. And continue the loading until the specimen fails.

(vi) Record the maximum load taken.

NOTE

Test at least 3 specimens.

Report

Date of casting :

Date of testing :

Age of specimen :

Curing condition :

CALCULATIONS

Range Calculation

Characteristic compressive strength at 28 days = N/ mm2

Area of cross section = pi.d²

Expected load = stress x area xf.s =

Range to be selected is……………………

COMPRESSIVE STRENGTH

Maximum load =

Compressive strength = (Maximum load/ Cross sectional area)

RESULT

Compressive strength of cylinder =…………………….N/mm²

Source http://theconstructor.org/.