452Full Depth Slab Replacement

452.1General Description

This work includes replacing Portland cement concrete pavement slabs, full or partial length. Remove the slabs according to the Plans or as directed by the Engineer. See Section 609. 452.1.01 Definitions General Provisions 101 through 150. 452.1.02 Related References

GDT 72 452.1.03 Submittals Obtain approval of the mix design from the Office of Materials and Research before using the mix.

452.2Materials

Ensure that materials used in full depth slab replacement conform to the following Specifications: Material Section Twenty-Four Hour Accelerated Strength Concrete Section 504 Dowel Bars and Bar Coatings Subsection 853.2.08 Epoxy Section 886 Silicone Sealant Subsection 833.2.06 452.2.01 Delivery, Storage, and Handling General Provisions 101 through 150.

452.3Construction Requirements

452.3.01 Personnel Furnish traffic control while the Department conducts slab movement testing described in Subsection 452.3.06.B. Quality of Work at no additional cost to the Department. 603 603 603 603 603 603 603

452.3.02 Equipment Use sufficient equipment to perform work such as drilling dowel holes, setting dowels, spreading, striking off, consolidating, screeding concrete, and sawing and sealing joints. Obtain the Engineer’s approval of the equipment before starting the work. Place the dowels at the locations specified on the Plans by using pneumatic or hydraulic drills and bits that will drill a 1-3/8 in. (35 mm) diameter hole in the existing concrete faces. 452.3.03 Preparation

Before placing the concrete, thoroughly clean the vertical exposed faces of the existing slabs to remove contaminates.

Remove debris and standing water from the base. Thoroughly compact loose base material by hand tamping before placing concrete. 452.3.04 Fabrication General Provisions 101 through 150. 452.3.05 Construction

Complete these steps to install the dowels:

Place the dowels at locations specified on the Plans.

these guidelines:

pavement with Type VIII epoxy bonding compound that meets the requirements in Section 886.

pavement.

(10 mm) within the vertical or oblique plane.

insertion of the dowel bar. Remove excess epoxy.

components as they are dispensed. Use a mixing nozzle at least 8 in. (200 mm) long. Or, use a machine that mixes the two components thoroughly to the proper ratio as the material is being placed.

concrete placement. 604 604 604 604 604 604 604

requirements of Subsection 853.2.08. Coat the protruding portion of the epoxy coated dowels with a thin film of grease or other approved material to ensure proper bond-breaking characteristics.

NOTE 1: Never drive dowels into a dowel hole with a sledge hammer or other device. NOTE 2: Coated dowels will be rejected if they cannot be freely inserted into a dowel hole.

Forms are not required for this work. The vertical faces of the existing pavement and shoulder bordering the replaced slab or joint area serve as the forms. However, if the shoulder is irregular or unstable:

prevent the concrete from intruding into the shoulder area.

at the correct grade.

remove the forms to avoid damaging the pavement.

The required concrete for the work will be 24-hour accelerated strength concrete that meets the requirements of Section 504. Obtain mix design approval from the Laboratory before use. Place the concrete only when the ambient temperature is 40 °F (4 °C) and rising. Do not place concrete when the underlying base material is muddy or frozen.

and prevents mix segregation.

NOTE: Do not allow workmen to walk in fresh concrete with shoes coated with earth or other foreign substances.

vibration to form a dense homogeneous mass throughout the area. 605 605 605 605 605 605 605

The finished surface, including joints, shall meet a surface tolerance of 1/8 in. in 10 ft. (3 mm in 3 m) in any direction. For slab replacements done in preparation for resurfacing of the pavement, the finished surface, including joints, shall meet a surface tolerance of 3/16 in. in 10 ft. (5 mm in 3 m) in any direction. Perform necessary corrections by grinding according to Section 431. The Engineer may order replacement if any replaced slab is low in relation to adjacent slabs. The Engineer will require replacement if it is determined that excessive pavement grinding is necessary to match the profile of the full depth slab replacement or if grinding the adjacent pavement would create a drainage problem. Do the following at no additional cost to the Department: • Perform all necessary corrections • Furnish all necessary traffic control personnel, materials, and equipment to detect deviations. • Grind or replace slabs to correct surface tolerance deviations If the Project involves resurfacing or grinding the pavement surface, a flat finish will be satisfactory. Otherwise, a broom or hand-tine finish will be required that will produce a surface texture depth of 0.20 in. (5mm) or greater as measured by GDT 72. The Engineer shall approve the finishing method and any deficient areas corrected to his or her satisfaction and performed at your expense.

Use the applicable portions of Section 504 regarding concrete mix and curing in this work.

Establish transverse and longitudinal joints within the slab replacement area by doing the following:

according to Plan details and Section 461.

Plans specify otherwise. Sawing and sealing of the reestablished joints is included in the bid cost for slab replacement.

Properly protect the concrete from rain before the concrete hardens by following these guidelines:

Protective materials include burlap or cotton mats, curing paper, or plastic sheeting material.

with the protective covering.

If night work is authorized on the Project, provide lighting for work performed at night for safety, traffic control, and work control and completion. Correct unsatisfactory work to the Engineer’s satisfaction at no additional cost to the Department.

Schedule slab replacements so that the concrete will have a curing time of at least four hours. Complete the work and open the lanes to traffic before sunset the day it is placed, unless authorized otherwise. The Engineer may require a longer curing period, mix design adjustments, or other corrective action to ensure sufficient concrete strength development before opening to traffic. 606 606 606 606 606 606 606

452.3.06 Quality Acceptance

Ensure that the finished surface tolerance, including joints, is 1/8 in. per 10 ft. (3 mm in 3 m) in any direction. Make corrections by grinding according to applicable items in Section 431.

Complete work that meets the requirements in the Specifications and Plans. Until Final Acceptance of this work, replace damaged or broken slabs due to the following: • Improper or unsatisfactory methods, equipment, or materials • Construction or public traffic Replace the slabs at no additional cost to the Department. The Department may also require removal and replacement of repaired slabs with a differential movement at the transverse joints greater than 0.01 in. (0.25 mm) at no cost to the Department. The Department will measure the movement using an 18,000 lb (8165 kg), single- axle load with dual tires and with the axial load centered 1 ft. (300 mm) from the edge of the shoulders as close to the transverse joints as possible. Testing will be done between 3:00 AM and 9:00 AM when slab movement is the greatest. The movement will be measured using dial gauges that can detect movement to the nearest 0.001 in. (0.025 mm). The Engineer will determine whether the slab movement test is required. 452.3.07 Contractor Warranty and Maintenance General Provisions 101 through 150.

452.4Measurement

Full depth replacement slabs are measured for payment by the cubic yard (meter) using the average squared dimensions times the average depth. Dowels and dowel placement are not measured for separate payment but are included in the Unit Price bid for full depth slab replacement. 452.4.01 Limits General Provisions 101 through 150.

452.5Payment

Full depth replacement slabs will be paid for at the Contract Unit Price per cubic yard (meter). Payment is full

compensation for:

• Furnishing materials including dowels, epoxy, and 24-hour accelerated strength concrete

• Performing work such as repairing shoulders if required, removing unsatisfactory material, sawing and

sealing new joints, and performing other work specified in this Specification

Payment will be made under:

Item No. 452 Full depth slab replacement Per cubic yard (meter)

452.5.01 Adjustments

General Provisions 101 through 150.. 607 607 607 607 607 607 607