Repairing a deteriorated parking structure involves many unknowns, uncertainties, and risks. To correct problems and restore the structure, owners must develop a program for evaluating conditions, making repairs, and setting up maintenance procedures that extend the life of the facility.
The first step is to perform a field survey to record existing conditions. Engineers locate areas where scaling, spalling, cracking, leaking, and leaching have occurred. Tests are used during the field survey to supplement observations. Next, determine distress severity and repair costs by answering two questions: how badly damaged are the structural members?; how much deteriorated concrete must be replaced, and at what cost?
Repair programs generally focus on three goals: repair deteriorated concrete floor slabs to restore integrity; provide durable protective wearing surfaces to minimize further deterioration; repair other underlying structural members to permit continued safe use of the facility. The choice of floor slab repair materials and methods is influenced by: nature and extent of deterioration; type of structure; funds available for repair. There are five approaches to restoring conventionally reinforced floor slabs: spot patch and seal; spot patch and traffic topping; bonded concrete overlay; full-depth slab replacement; and cathodic protection.
Repair documents, using the findings of the condition appraisal, consist of the following: plans, specifications, and details; priority assignments and cost estimates; contractor selection and bidding; provisions for observation of construction.
An effective program identifies maintenance needs, then establishes maintenance procedures and a schedule. Maintenance needs can be classified as operational, structural, or aesthetic.