How to Select UHPC Strengthening Components for Old Building Renovation?

In the renovation of old buildings, the selection of UHPC reinforcement components must be based on a four-dimensional evaluation system of "original structural condition, reinforcement objectives, construction conditions, and economy," scientifically selecting component forms such as "slabs, shells, beams, and columns." Drawing on 28 years of urban renewal practice, Qinglong Group has summarized a selection process: first assess the damage degree of the original structure (crack width, rebar corrosion rate), determine the reinforcement objectives (increase load-bearing capacity, extend service life, improve functionality), evaluate the construction space (whether wet operations are feasible, whether obstructions exist), and finally select components with overall cost in mind. In a Shenzhen project converting an old industrial plant into a cultural and creative center, for insufficient floor slab load-bearing capacity (a 30% increase required), we selected 15mm-thick UHPC composite slabs (compressive strength 150MPa); for insufficient beam shear resistance, we adopted UHPC U-shaped hoop external wrapping; for insufficient column capacity, we used 20mm-thick UHPC full wrapping. After reinforcement, the project's service life was extended by 30 years, with costs 60% lower than demolition and reconstruction. Scientific selection is the key to revitalizing old buildings.

Structural Condition Assessment is the Foundation of Selection

Through radar scanning, core drilling tests, rebar scanning and other methods, the original concrete strength, reinforcement configuration, and crack distribution are clearly identified. When load-bearing capacity is deficient by more than 50%, reinforcement should be applied cautiously, and demolition and reconstruction considered. Qinglong Group partners with authoritative appraisal institutions to issue detailed evaluation reports for every project.

Reinforcement Objectives Determine Component Forms

To increase flexural capacity: apply UHPC by bonding to bottom surfaces or spraying; for insufficient shear resistance: wrap with U-shaped plates or side plates; for seismic reinforcement: install UHPC shear walls or wing walls. In the renovation of a historical building in Nanning, we used sprayed UHPC (30mm thick) to reinforce brick walls, doubling lateral resistance.

Construction Conditions Constrain Scheme Feasibility

In narrow spaces (such as basements), use thin plates (15-20mm) for bonding; for high-altitude work, prefabricated panel hoisting is preferred; when rapid reopening to traffic is required, use rapid-hardening UHPC (1-day strength ≥50MPa). We possess specialized construction equipment, such as robotic spray systems, adaptable to various working conditions.

Economic Comparison Achieves Maximum Value

Comparing reinforcement with demolition and reconstruction costs, reinforcement typically costs 1/3 to 1/2 of demolition and reconstruction. Calculate full life-cycle costs, taking into account the benefits of extended service life and improved functionality. Qinglong Group provides multi-scheme comparisons to help clients make informed decisions.

Old buildings are carriers of urban memory. With UHPC reinforcement technology, Qinglong Group safely renews old buildings, restoring their vitality.