B01-Atch 1 PWS Attachment_1b Cast Concrete Structure Maintenance Instruction.pdf

ACTIVITY ID DATE

CONTRACT NO CONTRACT TITLE SUBMI NO

SUBM ITEM DESCRIPTION

SPEC SECTION SPEC PARAGRAPH SPEC PAGE NO

CONTRACTOR/QUALITY CONTROL MANAGER DATE

COMMENTS FOR DETAILED REVIEWER:

DETAILED REVIEWER 1 COMMENTS:

DETAILED REVIEWER 1 NAME/SIGNATURE: TITLE RESPONSE DATE

DETAILED REVIEWER 2 COMMENTS:

DETAILED REVIEWER 2 NAME/SIGNATURE: TITLE RESPONSE DATE

APPROVER'S COMMENTS:

SUBM STATUS GOVERNMENT CONSTRUCTION MANAGER DATE

4296/2C (9/98) SHEET 1 of

15/11/2023

Improve Weapons Storage Facility at Camp Darby, Livorno, Italy

SUBMITTAL TRANSMITTAL

201 78 00 - Closeout Submittal

15/11/2023

N62470-17C-5002 230A

(SD-10) Cast in place Concrete Structure Maintenance Instruction

Contractor submits to GOV Cast in place Concrete Structure Maintenance Instruction.

This is part of Closeout Submittal required.

1.3 - Operation and Maintenance Data

Improve Weapons Storage Facility (WSF)

Camp Darby, Pisa, Italy

Contract No. N62470-17-C-5002

Cimolai Internal Project Number: 2017.034

U.S. ARMY GARRISON VICENZA - CAMP DARBY

IMPROVE WEAPONS STORAGE FACILITY

Contract N62470-17-C-5002

Cast in place Concrete Structure Maintenance Instruction

REV. DATE Descritpion

0 15 November 2023 Cast in place Concrete Structure Maintenance Instruction

Table of Contents:

INTRODUCTION

1.0 SCOPE AND APPLICATION

2.0 TYPES OF CONCRETE STRUCTURES

3.0 IMPORTANCE OF REGULAR MAINTENANCE

4.0 SAFETY PRECAUTIONS

5.0 PERSONNEL

6.0 METHOD OF INSPECTION

7.0 TOOLS AND EQUIPMENT

INTRODUCTION

This comprehensive guide is designed to assist you in ensuring the longevity and structural integrity of your concrete structures.

The primary purpose of this manual is to provide a structured approach to concrete structure maintenance. It outlines procedures, schedules, and safety considerations, ensuring the continued functionality and safety of our project's concrete components.

1.0 SCOPE AND APPLICATION

This manual is specifically tailored to the unique concrete structures within ERI expansion project, which include:

- ASA AREA 8 Loading and unloading dock: Retaining walls

- ASA AREA 9 Inspection Quay: Retaining Walls and Shed Foundations

- ASA AREA 6 Fixed Bridge: Foundations

- ASA AREA 3 Swing Bridge: Foundations, Plinths

- MUNITION DOCK: Pile Head Beam, Bitta Beam, Wall and Overflow Channel

- LTA AREA 2: Joint Wall

- ASA AREA 8 an 9: Concrete slabs

To ensure these structures continue to serve their intended purposes effectively and safely, this manual provides you with a structured approach to maintenance, including safety precautions, types of concrete structures, and the importance of regular maintenance.

2.0 TYPES OF CONCRETE STRUCTURES

The project comprises various concrete structures, each of these structures necessitates specific maintenance approaches to address their specific functions. In particular, the manual identify two different types of concrete structures:

- vertical elements (such as block foundations, retaining walls, elevated concrete structures in general)

- Concrete slabs

3.0 IMPORTANCE OF REGULAR MAINTENANCE

Regular maintenance is a critical component of preserving the functionality and longevity of concrete structures within any project. The establishment of scheduled maintenance practices is fundamental to prevent deterioration, extend their lifespan, and ensure their continued reliability.

4.0 SAFETY PRECAUTIONS

Safety is of the upmost importance when performing maintenance on concrete structures. Please ensure the well-being of all individuals working with or near these structures in accordance with safety rules and regulations.

CAREFULLY READ THE ENTIRE MANUAL BEFORE PROCEEDING WITH THE USE AND

MAINTENANCE OF THE RELEVANT STRUCTURES.

5.0 PERSONNEL

This manual is intended exclusively to personnel assigned to operation and maintenance operations (inspection, preventive and corrective maintenance). The operations of use and maintenance must be entrusted to suitable and qualified persons. The machines can only be used by specialized personnel. Such persons must always have the instructions and must carefully observe their contents.

Please refer also to other manual such as: 2017034 ODP - MDP 10001A 3 (MOVABLE BRIDGE OPERATING SYSTEM - USE AND MAINTENANCE MANUAL) and for steelwork structure inspection see the document 2017034 WSF - Steel Structure Maintenance Instruction.

6.0 METHOD OF INSPECTION

Visual inspection to detect possible anomalies preceding structural failure phenomena.

Visual inspection is a fundamental component of assessing the condition of concrete structures, providing valuable insights into the surface integrity and identifying potential issues that may compromise structural integrity or aesthetics. To ensure the efficacy of visual inspections, it is imperative to follow systematic guidelines that encompass a comprehensive approach.

Inspectors should systematically cover the entire surface of the concrete structure, considering both macroscopic and microscopic details. This involves assessing the overall appearance, looking for surface defects such as cracks, spalling, discoloration, or any other anomalies that may have developed over time.

Proper lighting conditions are essential for detecting subtle imperfections and ensuring accurate assessments. Inspections should ideally be conducted during daylight hours, and supplementary lighting may be necessary, especially for areas with limited natural light. Adequate lighting not only facilitates the identification of surface irregularities but also aids in capturing detailed documentation for further analysis.

Highlight the significance of utilizing appropriate tools during the inspection process. Depending on the needs and actual structure conditions, inspectors may employ tools such as magnifying glasses, flashlights, or mirrors to access hard-to-reach areas. Additionally, specialized tools like crack width gauges can aid in precise measurements, contributing to a more accurate evaluation of any observed defects.

Moreover, inspectors to be well-trained in recognizing different types of concrete distress and to distinguish between cosmetic issues and those that may have structural implications. This expertise ensures that inspections are not only thorough but also capable of providing a nuanced understanding of the concrete's overall condition.

Frequency and periodicity: yearly. Extra inspections should be planned during potential extraordinary natural events which may impact integrity of the structures (earthquake, flooding, etc.)

6.1.1 VISUAL INSPECTION STEPS

1. Prepare for Inspection:

- Gather necessary equipment, including a flashlight, binoculars, a measuring tape, and a notebook for recording observations.

- Review any previous inspection reports or maintenance records to identify areas of concern, if available.

2. Safety Precautions:

- Prioritize safety by wearing appropriate personal protective equipment (PPE) such as hard hats, safety vests, and, if necessary, fall protection gear.

- Ensure proper access to the inspection areas, considering scaffolding, ladders, or other safety measures, if and when needed.

3. Walkthrough Inspection:

- Begin with a general walkthrough to observe the overall condition of the concrete structures.

- Look for visible signs of distress, such as cracks, spalling, or discoloration.

4. Focus on Specific Areas:

- Pay special attention to critical areas identified in the project, including joints, connections, and load-bearing components.

- Use binoculars to inspect areas that are difficult to reach.

5. Examine Surface Conditions:

- Check for efflorescence, mold, or any surface deposits that may indicate underlying issues.

- Assess the condition of protective coatings or sealants.

6. Crack Inspection:

- Measure and record the width, length, and depth of any visible cracks.

- Differentiate between surface cracks and structural cracks, considering their location and characteristics.

7.Joint Inspection:

- Examine the condition of joints, including seals and any signs of movement or misalignment. Look for signs of wear, tear, or deterioration, including any visible damage to the joint sealant or underlying materials. Check for proper alignment and confirm that the joint still allows for the necessary movement to accommodate thermal expansion and contraction.

- Check for proper functioning of expansion joints and ensure they are free from debris.

8. Documentation:

- Document all observations, measurements, and findings in a structured manner.

- Take photographs to provide visual documentation and aid in future comparisons.

9. Report and Recommendations:

- Compile a comprehensive inspection report, detailing the condition of each component and recommending necessary maintenance or repairs.

- Prioritize the identified issues based on their severity and potential impact on structural integrity.

10. Follow-up Actions:

- Based on the inspection report, develop a maintenance plan outlining specific actions, timelines, and resources required for repairs or preventive measures.

- Implement the recommended actions promptly to address any issues identified during the visual inspection.

6.1.2 COMMON CONCRETE PROBLEMS

Common problems may include surface cracks, spalling, or corrosion of reinforcement.

Thorough understanding of these issues is vital for effective maintenance planning and execution.

WARNING: The suggested solutions provided below adhere to standard practices and widely accepted industry standards and expertise. In the event that repairs are deemed necessary, it is imperative to coordinate and customize any interventions following a thorough inspection and the involvement of specialized companies possessing the requisite expertise and knowledge.

6.1.2.1 Surface Cracks:

• Cause: Surface cracks can result from shrinkage, temperature fluctuations, frost and thaw cycle or water penetration over time combining with frost and thaw cycle

• Possible Solution:

Minor Cracks:

• Sealants: For hairline cracks or small fissures, applying specialized sealants is an effective solution. These sealants not only prevent water infiltration but also help in maintaining the aesthetic appearance of the concrete surface.

• Epoxy Injections: When dealing with slightly larger cracks, epoxy injections can be employed. Epoxy, a strong adhesive, not only fills the crack but also provides structural reinforcement. This solution is particularly effective for cracks in load-bearing structures.

Deeper Cracks:

• Patching: Deeper cracks may require more extensive repairs, involving the removal of damaged concrete and the application of a patching material. This process restores the integrity of the concrete surface and prevents further deterioration.

• Resurfacing: In cases where the damage is more extensive or the structural integrity is compromised, resurfacing the entire concrete surface may be necessary. This involves applying a new layer of concrete, providing a fresh, durable surface while addressing underlying issues.

6.1.2.2 Spalling:

• Cause: Spalling occurs when the surface of concrete breaks off, often due to freeze-thaw cycles or corrosion of reinforcement.

• Possible solution: Repair spalled areas by removing damaged concrete, applying a bonding agent, and then patching or resurfacing.

6.1.2.3 Corrosion of Reinforcement:

• Cause: Exposure to harsh environmental conditions or the presence of chloride ions can lead to reinforcement corrosion.

• Possible solution: Implement corrosion protection measures such as applying corrosion inhibitors, using stainless steel reinforcement, and maintaining proper concrete cover.

6.1.2.4 Efflorescence:

Efflorescence (crystalline deposit of salts on the concrete surface) is a common aesthetic concern. While it doesn't necessarily affect the structural integrity, it can impact the visual appeal of our concrete structures.

• Cause:

Efflorescence occurs when water-soluble salts present in the concrete mix or from external sources migrate to the surface and crystallize. This is often triggered by water movement within the concrete.

• Possible solution:

Surface Cleaning: Efflorescence can be addressed through surface cleaning. Brushing or power washing the affected areas with a mild acid solution can dissolve the salt deposits and remove them from the surface.

Sealing: Applying a high-quality concrete sealer helps to create a barrier, preventing water from penetrating the concrete and reducing the potential for efflorescence.

6.1.2.5 Appearance of Mold:

The appearance of mold on concrete surfaces, especially in humid or damp environments, is a concern that requires both aesthetic and health considerations.

• Cause:

Mold growth is encouraged by the presence of moisture, organic matter, and favorable environmental conditions. Poor drainage, high humidity, or insufficient ventilation can contribute to mold development.

• Possible solution:

Cleaning and Disinfection: Remove mold from the concrete surface by scrubbing with a mixture of water and mild detergent or an appropriate mold-killing solution. After cleaning, thoroughly dry the surface.

Improved Ventilation (for internal structures, if any): Addressing underlying moisture issues by improving ventilation and drainage helps prevent mold recurrence.

NOTE:

Visual inspection serves as the initial step in assessing concrete structures, offering a preliminary overview of their condition. In the presence of damages such as cracks, a more in-depth evaluation by specialized and trained personnel becomes imperative. Common non-destructive tests may include Ultrasonic Pulse Velocity (UPV) to detect voids and assess concrete uniformity, Rebound

Hammer Test for estimating concrete strength, and Visual Inspection with Advanced Techniques using tools like ground-penetrating radar for comprehensive defect identification.

On the destructive side, Core Sampling allows for detailed analysis of concrete strength, while Load

Testing evaluates load-carrying capacity and structural performance. Employing a combination of these methods ensures a thorough understanding of the concrete structure's health and aids in informed decision-making for maintenance or remediation.

7.0 TOOLS AND EQUIPMENT

Please find below a list of necessary or ausiliary tools which may be needed for concrete inspections, depending on results of visual inspection and status of the structures:

- Flashlight: Essential for illuminating dark or hard-to-reach areas during inspections.

- Tape Measure: Used for measuring dimensions, crack widths, and other critical distances.

- Magnifying Glass: Aids in detailed examination of small cracks, surface imperfections, or material conditions.

- Total Station: Optical instrument for precise measurement of angles, distances, and elevations during structural surveys.

- Rebound Hammer: Measures the surface hardness of concrete, providing an indication of its compressive strength.

- Ultrasonic Testing Equipment: Used to assess the internal condition of concrete by measuring the velocity of ultrasonic pulses.

- Crack Width Gauge: Measures the width of cracks in concrete, aiding in the classification of crack severity.

- Inclinometer: Monitors structural movements and deformations, providing valuable data for ongoing assessments.

- Concrete Core Drilling Equipment: Allows for the extraction of core samples for laboratory testing, providing information on concrete strength and quality.

- Thermographic Camera: Identifies variations in temperature, revealing potential issues related to insulation, moisture, or structural anomalies.

- Levels and Plumb Bobs: Ensures accurate measurements of levelness and verticality in various structural components.

- High-Resolution Camera: Captures detailed images of surface conditions for documentation and analysis.

- Safety Gear: Includes personal protective equipment (PPE) such as hard hats, safety glasses, gloves, and appropriate footwear.

- Moisture Meter: Measures the moisture content of concrete, aiding in the detection of potential water-related issues.

- Non-Destructive Testing (NDT) Kits: Includes tools like Schmidt hammers, cover meters, and pull-off testers for a comprehensive assessment of concrete properties.

- Binoculars: Useful for inspecting hard-to-reach or elevated areas from a distance.

- Dust Mask and Respirator: Protects inspectors from airborne particles and dust during inspections.

- Notebook and Pen: Essential for recording observations, measurements, and other pertinent information during inspections.

- Safety Barriers and Signage: Used to secure inspection areas and communicate potential hazards to others on the site.