In reinforced cement concrete (RCC) design using the working stress method, what is the commonly adopted allowable (permissible) tensile stress for mild steel used in stirrups (shear reinforcement)? Choose the closest standard value in kg/cm².

Introduction / Context:
In RCC design under the traditional working stress method, permissible (allowable) stresses are specified for different materials. For mild steel (plain bars) used as stirrups or ties, designers use a standard allowable tensile stress to proportion shear reinforcement safely while controlling service-level behavior.

Given Data / Assumptions:

• Material: mild steel stirrups (typical yield strength of plain MS ≈ 250 MPa).
• Design philosophy: working stress method with permissible stresses.
• Unit system: kg/cm² as used in many legacy RCC problems.

Concept / Approach:
Permissible stress for mild steel in tension under working stress design has been conventionally taken around 1400 kg/cm². This value reflects historical safety factors applied to the characteristic strength to keep service-stress levels within elastic range and to limit crack widths under service loads.

Step-by-Step Solution:
Identify the steel type: mild steel (not high-strength deformed bars).Use standard permissible tensile stress for mild steel in shear reinforcement design = about 1400 kg/cm².Select the matching option.

Verification / Alternative check:
Legacy handbooks and many exam-oriented RCC texts list 1400 kg/cm² as the permissible tensile stress for mild steel in tension for working stress calculations, especially for stirrups and ties. Modern limit-state codes use different approaches (factored capacities), but the question context is clearly working stress in kg/cm².

Why Other Options Are Wrong:

• 190 kg/cm² and 230 kg/cm²: Far too low; they do not reflect conventional permissible levels for mild steel tension in working stress design.
• 260 kg/cm²: Still much lower than practice and would result in uneconomical, over-conservative reinforcement.

Common Pitfalls:
Mixing up permissible stresses of mild steel with those of high strength bars; confusing limit-state design parameters with working stress permissible values; converting MPa to kg/cm² incorrectly (1 MPa ≈ 10.197 kg/mm² = 101.97 kg/cm²).

Final Answer:
1400 kg/cm²