Prestress Analyzer — Ebora Reinforced & Prestressed Concrete

🪢 Prestress Analyzer

Prestress Analyzer

Check fiber stresses in a prestressed beam at transfer and service against the code allowables, or estimate the prestress losses (elastic shortening, shrinkage, creep, relaxation — plus anchorage & friction for post-tensioning). SI units, NSCP 2015 / ACI 318-14. Compression is positive; tension shows as a negative stress.

⭐ Free to use · Balance … EP

① System & task

Prestressing system

What do you want to compute?

Sign convention: stresses in MPa, compression positive. A sagging moment M (positive) gives compression at the top and tension at the bottom. Eccentricity e is positive when the tendon is below the section centroid.

② Section properties

Width b (mm)

Depth h (mm)

A = b·h, I = b·h³⁄12, yₜ = y_b = h⁄2 are computed for you.

Area A (mm²)

Moment of inertia I (mm⁴)

y to top fiber, yₜ (mm)

y to bottom fiber, y_b (mm)

③ Concrete strengths

f′_ci at transfer (MPa)

f′_c at service (MPa)

④ Prestress & moments

Initial prestress P_i (kN)

Eccentricity e (mm)

Positive = tendon below the centroid.

Moment at transfer M_g (kN·m)

Self-weight moment acting at release.

Total service moment M_t (kN·m)

M_g + superimposed dead + live.

Effective-prestress ratio R

P_e = R·P_i. Use 0.85, or paste the R from the Loss tab.

④ Tendon & modulus

Tendon modulus E_p (MPa)

Tendon area A_ps (mm²)

Used with P_i to get f_pi if f_pi is left blank.

Initial tendon stress f_pi (MPa)

Initial prestress P_i (kN)

Eccentricity e (mm)

Moment at transfer M_g (kN·m)

⑤ Loss parameters

Concrete E_c (MPa)

Concrete E_ci (MPa)

Shrinkage strain ε_sh

Creep coefficient K_cr

f_cds — sustained DL stress at tendon (MPa)

Relaxation RE (MPa)

🪢 Results

—

Summary

Worked steps

⚠️ Preliminary check only. Class U (uncracked) allowable stresses are assumed and the loss method shown is a lump-sum component estimate. Confirm the allowable-stress class (U / T / C), the exact loss method, and every coefficient against the NSCP 2015 / ACI 318-14 and your course before using these numbers for design.

Prestress Analyzer

① System & task

② Section properties

③ Concrete strengths

④ Prestress & moments

④ Tendon & modulus

⑤ Loss parameters

⑥ Post-tensioned extras

🪢 Results

Worked steps