Guide for Repairing Damaged Buildings

A practical repair manual issued by MTPTC after the 12 January 2010 earthquake, financed by the World Bank and carrying the Minister's foreword of 28 November 2010. It came out of a pilot project to repair damaged units, whose two preconditions the foreword names: identifying which houses are repairable, and having a tool that standardizes the repairs so that different teams work the same way. The stated purpose is to recover part of the built heritage of the metropolitan area and let a significant share of the population return home safely.

The introduction sets the scope of the problem and then narrows it hard. Hundreds of thousands of dwellings, office buildings, shops, hospitals, schools and churches collapsed or were heavily damaged, but many buildings survived with little or no damage, which the guide reads as evidence that this construction type has some capacity to resist lateral seismic forces and that repair can improve its overall performance. The guide therefore addresses moderately damaged buildings only, and only those of one to two storeys: the same techniques may apply to taller buildings, but those require a specific structural analysis.

The building evaluation program is the entry point. Assessments used a modified version of the ATC rapid-evaluation method created specifically after the Haiti disaster, which assigns each building a colour tag: green for buildings safe to occupy with minor damage and no structural repairs required, yellow for limited use with moderate damage where structural repairs are necessary, red for buildings dangerous to occupy that put their occupants and surroundings at risk. This guide addresses the yellow category.

The technical half is organized as materials then repairs. Materials cover the preparation of concrete block masonry elements, mortar, concrete, concrete grout, and steel bars for reinforced concrete and masonry. The standard repairs are lettered and each is worked through in detail: A1 replacing a wall with diagonal cracks; B1 and B2 replacing a wall with an opening, with and without a lintel; C1 replacing a displaced wall; D1 replacing a lintel; E1 and E2 a wall partially detached at the top; F1 a minor crack in a wall; G1 spalled concrete cover at the top of a column; H1 and H2 repairing a concrete column that has lost its cover and part of its base concrete.

The guide also flags the indirect factors that drive execution and cost, which repair manuals usually omit: access to the damaged structure, debris removal, and protection of neighbouring structures. It closes by describing itself as an evolving document that does not cover every case and should be revised as field experience accumulates.

A note on this record's sources. The PDF's text layer is written in a shifted font encoding, so the stored text is unreadable as extracted; it was decoded for this record by reversing the shift. Digits did not survive that encoding, so the casualty and damage figures quoted in the introduction are absent from the stored text and are not repeated here.