PEVI_RepointingRPT_2016-06-23_rev_(Spring_Follow-Up_12-13_only).pdf

Perry's Victory and International Peace Memorial Repointing and Cleaning Trials

June 23, 2016

REASSESSMENT – JUNE 2016

A third site visit was made by WJE on June 16, 2016, to evaluate the trials performed in September and October 2015. The trials were evaluated to assess if any additional cracking of the mortar joints occurred during the thermal cycling of the winter months. The trials were evaluated up-close from pipe scaffolding, using field magnification up to 10x. Our observations are summarized in Table 4. Representative photographs are provided in Figure 20 and Figure 21.

Table 4. Observations of September and October 2015 Trials Sample Observations 1A Minor new hairline cracks (less than 0.005 inch wide) along joint appeared since previous evaluation that appear to be related to shrinkage of the mortar rather than bond separations.

2A Minor new hairline cracks (less than 0.015 inch wide) along joint appeared since previous evaluation

3A Minor new hairline cracks (less than 0.005 inch wide) along joint appeared since previous evaluation

4A Cracks remain similar to previous evaluation (approximately 50 percent of joints with cracks).

5A Cracks remain similar to previous evaluation (approximately 25 percent of joints with cracks).

6A Cracks remain similar to previous evaluation (approximately 10 percent of joints with cracks).

7A Dark gray appearance; white deposits previously observed remain.

8A Isolated orange staining in mortar joins. Very minor new hairline cracks emerged.

White deposits previously observed remain.

9A No cracks 10A No cracks 11A No cracks 1B Hairline cracks associated with bondline were observed, but cracks are <0.005 inch wide and require magnification to view. Minor destructive testing was performed and cracks seem isolated to outer 1/4 inch of the joint.

2B Hairline cracks associated with bondline were observed, but cracks are <0.005 inch wide and require magnification to view.

3B No cracks

While slightly more cracking was observed in the trials during our June 2016 observations compared to the fall 2015 observations, the cracks observed are typically very fine (less than 0.005 inch wide). Very fine cracks of this type would not allow water to enter the masonry system and do not represent a performance concern. Therefore, our previously stated conclusions and recommendations are unchanged. We recommend the trial repairs be left in place and used as a basis for comparison to evaluate the mock-ups performed by the selected contractor at the start of his work.

Aside from the close-up assessment of the mortar joints as described in the table above, the following observations were made during our site visit:

Water was actively dripping from the mortar joints at several locations. It had rained during the previous night (Figure 22).

Efflorescence deposits have formed at the repointed trials (Figure 23 and Figure 24).

Perry's Victory and International Peace Memorial Repointing and Cleaning Trials

June 23, 2016

As previously discussed, water can currently enter the masonry through failed sealant joints throughout the column. Where water exits the wall system, efflorescence is deposited on the surface. The efflorescence is a result of calcium carbonate and calcium hydroxide from the concrete back-up wall leaching onto the surface of the granite. Currently, the water exits the masonry system at areas where the sealant has failed, which concentrates the formation of efflorescence at those locations. Further, cracks and voids in the back-up construction likely preferentially direct water to specific areas. As noted in our June 1, 2015, report, repointing of the joints with mortar will provide an effective long-term joint weather seal to mitigate water infiltration. The mortar will also allow the improved transmission of water out of the wall. In addition, water migrating from the wall will likely be less concentrated, as compared to the existing situation in which water migrates out at isolated failed sealant joints. The repointing of the column with mortar will allow the diffused drying of the back-up materials, which are wet from long term water infiltration. This work should help to reduce the rate and concentration of efflorescence formation as well as reduce the deteriorating effects of freezing and thawing. As also noted in our report, ongoing inspection and maintenance will be necessary to identify and remove any areas of efflorescence and to repair open/damaged joints.