Structural engineering in Cartagena

What does the NSR-10 require to build in Cartagena?

In reinforced concrete, the NSR-10 accepts structures with minimum energy dissipation capacity (DMI) in the low hazard zone, with the simplest detailing, and for occupancy groups I and II it limits the irregularity checks to a few types (A.3.3.6).

If the geotechnical study gives a type D profile, the Cartagena design spectrum for a residential or office building (occupancy group I) has a plateau of Sa = 0.40 g up to TC = 0.72 s, and TL = 5.76 s. With another soil or another use the values change: work them out with the design spectrum.

What does salt air require in Cartagena?

In a city surrounded by the sea, concrete exposed to moisture and to chlorides from seawater, salt or sea spray belongs to the NSR-10's exposure class C2, which requires a maximum water-cementitious materials ratio of 0.40, a minimum strength of 35 MPa and no more than 0.15 % water-soluble chlorides in reinforced concrete (tables C.4.2.1 and C.4.3.1). The minimum covers for cast-in-place concrete are 75 mm against the ground and 50 mm for No. 6 bars or larger exposed to the weather (C.7.7.1), and in corrosive environments they must be increased (C.7.7.6).

How is a heritage building intervened?

For buildings declared historic heritage, where there are severe restrictions on reaching the safety of a new building, the NSR-10 allows a lower level of seismic safety, justified by the engineer, accepted by the owner and recorded before a notary; it does not apply to occupancy groups III and IV (A.10.9.2.5). In those cases the limited-safety ground motions are used, with the Ae parameter, which in Cartagena is 0.05 (A.10.3). They are never used to design new buildings (A.10.3.1).

When does Law 1796 require review and technical supervision in Cartagena?

The rule is the same throughout the country: when the lot allows more than 2,000 m² to be built, whatever the use, Law 1796 of 2016 requires an independent review of the structural designs before the permit and independent technical supervision during construction. Buildings in occupancy groups III and IV, such as schools and hospitals, require technical supervision whatever the area (A.1.3.9.1). Check your case with the Law 1796 assistant.