121.According to IS: 456-1978, the maximum strain in concrete at the outermost
compression fibre in the limit state design of flexural member is 0.0035
122.The minimum eccentricity for design of columns as per IS : 456-1978 is
1/500 +D/30
subjected to a maximum of 20 mm. where l = unsupported length of the
column and
123. For the deflection of simply supported beam to be within permissible limits, the ratio of its span to effective depth as per IS : 456-1978 should not exceed
20
124. The development length of bars of diameter Φ, as per IS : 456-1978 is
given by
125.For bars in tension, a standard hook has an anchorage value equivalent to a straight length of 16Φ
126.The creep strains are caused due to dead loads only
127. The effect of creep on modular ratio is to increase it
128. Shrinkage of concrete depends upon i) humidity of atmosphere
ii) passage of time
129. Due to shrinkage stresses, a simply supported beam having reinforcement
only at bottom tends to deflect downward
130. In symmetrically reinforced sections, shrinkage stresses in concrete and steel are respectively tensile and compressive
131. A beam curved in plan is designed for bending moment, shear and torsion
132. In a spherical dome subjected to concentrated load at crown or uniformly
distributed load, the meridional force is always compressive
133. Sinking of an intermediate support of a continuous beam
i) reduces the negative moment at support
ii) increases the positive moment at centre of span
134. The maximum value of hoop compression in a dome is given by
wR/2d
135. In a spherical dome the hoop stress due to a concentrated load at crown is
tensile everywhere
136. In a ring beam subjected to uniformly distributed load
i) shear force at mid span is zero
ii) torsion at mid span is zero
137. In prestressed concrete forces of tension and compressions
remain unchanged but lever arm changes with the moment
138. The purpose of reinforcement in prestressed concrete is
to impart initial compressive stress in concrete
139. Normally prestressing wires are arranged in the lower part of the beam
140. Most common method of prestressing used for factory production is Long line method
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