The report summarizes an inspection of a two-story commercial/residential building in Quezon City to assess its structural stability. The building was constructed in the 1970s and renovated in 2009 without proper permits. An inspection found cracks, spalling, and corrosion. Tests determined the concrete strength was only 74% of the design strength. Due to the age of the building, lack of earthquake standards when built, and substandard concrete, the report recommends demolishing and rebuilding the structure, as retrofitting would be over 50% of the cost of new construction.
The report summarizes an inspection of a two-story commercial/residential building in Quezon City to assess its structural stability. The building was constructed in the 1970s and renovated in 2009 without proper permits. An inspection found cracks, spalling, and corrosion. Tests determined the concrete strength was only 74% of the design strength. Due to the age of the building, lack of earthquake standards when built, and substandard concrete, the report recommends demolishing and rebuilding the structure, as retrofitting would be over 50% of the cost of new construction.
The report summarizes an inspection of a two-story commercial/residential building in Quezon City to assess its structural stability. The building was constructed in the 1970s and renovated in 2009 without proper permits. An inspection found cracks, spalling, and corrosion. Tests determined the concrete strength was only 74% of the design strength. Due to the age of the building, lack of earthquake standards when built, and substandard concrete, the report recommends demolishing and rebuilding the structure, as retrofitting would be over 50% of the cost of new construction.
The report summarizes an inspection of a two-story commercial/residential building in Quezon City to assess its structural stability. The building was constructed in the 1970s and renovated in 2009 without proper permits. An inspection found cracks, spalling, and corrosion. Tests determined the concrete strength was only 74% of the design strength. Due to the age of the building, lack of earthquake standards when built, and substandard concrete, the report recommends demolishing and rebuilding the structure, as retrofitting would be over 50% of the cost of new construction.
Building/Structure Inspection and Assesment Report
Description of Structure : Two Storey Commercial/Residential
Location : 336 Roosevelt Avenue Cor. Road B Brgy. Veterans Village Quezon City Owner : Ms. Josefina Ramos Mendoza Purpose : The purpose of the building inspection and assessment is to comply with the requirement of the Building official of Quezon City for the submission of the building certificate of structural stability. 1. Background The subject two-storey commercial/residential building is a composite structure of steel reinforced concrete and wood, built in the 1970s.
Sometimes in 2009, the building was leased to a party involved in the sales of motorcycles. It was on this occasion that the building was renovated (addition of mezzanine). The changes seemed to lack permit and design by a structural engineer.
At present the building is occupied by the lease and other sub leases.
2. Inspection and Assessment
The building owner, through her representative contracted the services of A-MaDe Structural Retrofitting and Consultancy to conduct the necessary inspection and structural assessment of the building and the issuance of Structural Stability Report in compliance with the requirement of the Building Official of Quezon City.
The first inspection was conducted on July 10, 2014. The activities include ocular/physical observation, interviews with tenants and a walk-through around the structure.
Observations: 1. The state of the building is in need of regular maintenance and repair. 2. The mezzanine is used commercially in the absence of approved renovation plan by a structural engineer. 3. The columns and beams revealed no cracks and deflection. 4. The slab soffit showed areas of spalling and corrosion. 5. Other violations as stated in the Building official inspection report includes: 5.1 Improper Electrical Wiring Installation 5.2 No maintenance program 5.3 Insufficient provision for BP 344 5.4 Obstructions on Fire Exit
3. The structural assessment was conducted on July 15, 2014. The activities during the day include, scanning of reinforcing steel bars on columns, beams and slab. Determination of concrete compressive strength by rebound hammer.
1. Compressive Strength (ASTM) The average compressive strength fc is 230 psi. This is only 74% of the standard design compressive strength of 3,000 psi for this type of structure.
6. Conclusion and Recommendation
Since the building was constructed in the 70s, the prevailing building code at the time lacked the ductility requirement for earthquake and the seismic design consideration for a magnitude 7.3 earthquake that would be generated by the rupture of the Marikina Fault Line.
Moreover, the actual concrete strength is only 74% of the design strength which would lead to failure of the structure.The additional mezzanine which is not originally part of the structure would also contribute to the collapse of the building in case of a major earthquake.
Our recommendation is to demolish the existing building since the cost of retrofitting would be very high. (Over 50% of the cost of new building)