Garver Feed Mill Condition Evaluation

Transcription

1 Garver Feed Mill Condition Evaluation

2 OUTLINE Brick masonry overview Condition assessment & methodology Project overview Existing conditions Stabilization Probable costs Summary

3 BRICK MASONRY OVERVIEW

4 Brick 4000 years old technology Simple technique of stacking to make walls Strong Long lasting Fire proof

5 Brick is like a loaf of bread Hard crust outside, Soft core inside

6 Cross section of early 20 th century mold made brick Swirl is due to kneading of clay before it was set in mold

7 Cross section of early extruded brick Horizontal lines from extrusion process

8 Mortar A cushion/seal between bricks/bearing surface Bonding agent/surface enhancer A mixture of cement, sand & lime Sacrificial

9 HISTORIC MASONRY

10 Mass Wall Multiple wythes of brick Load bearing Thermal mass

11 Mass Wall Sheds most moisture Absorbs some moisture Moisture dissipated by movement of heat and by evaporation Soft bricks/soft joints No provision for expansion

12 CONTEMPORARY MASONRY

13 Screen Wall Single wythe of brick with backup material Non load bearing Expansion joints

14 Screen Wall Assumes water will penetrate wall Provides for water intrusion Provides for water escape

15 COMMON ISSUES

16 Moisture penetrates walls Freeze thaw action

17 Moisture penetrates walls Surface spalling

18 Moisture trapped in walls Efflorescence- deposit of salts

19 Moisture trapped in walls Rising damp

20 Mortar harder than brick Brick erodes, mortar remains

21 Movement Vertical and horizontal displacement

22 PROPER TREATMENTS

23 Secretary of the Interior s Standards National Standards & Guidelines

24 Cleaning Sample test panel, mildest treatment Typically done before repointing or replacement

25 Cleaning Medium bristle brush and non-ionic detergent Rinse thoroughly

26 Cleaning Sand blasting not recommended

27 Repointing Carefully remove deteriorated mortar Replace only deteriorated mortar

28 Repointing Replace with mortar softer than the brick Match original mortar color and joint type

29 Repointing Match composition, color and joint type of original

30 Repointing Incorrect color mortar and wider joints

31 Brick replacement Very difficult to match new brick to old Difficult to match new mortar color to old

32 Brick replacement Restoration of façade with reclaimed and recycled brick

33 CONDITION ASSESSMENT & METHODOLOGY

34 Assessing an Existing Masonry Building Existing Condition Survey / Laser Scan Photographic Documentation Sounding Inner Wall Sampling Laboratory tests Chemical Analysis Petrographic Examination Brick Absorption Tests Brick & Prism Compression Test

35 EXISTING CONDITION SERVEY with a Laser Scanner Highly portable laser scanning equipment. Scanner and tripod Battery and computer 3D laser scanning technology provides a snap shot in time, an archive of information that does not change.

36 Laser Scan

37 Photographic Documentation

38 Sounding & Inner Wall Sampling Energy absorption vs. rebound Solid wall- ping sound Hollow wall - thud sound Deteriorated wall muted thud Visual survey of inner wall Are the bricks solid? Is the mortar solid? Are there gaps in mortar? Is the wall wet? Retrieve samples for lab test.

39 Laboratory Tests: Chemical Analysis of Masonry Mortar Finding the proper mortar match for repairs ASTM C 1324 is a combination of test procedures for microscopic examination and chemical analysis of mortar to determine components of masonry mortar and quantities of components. In other words, reverse engineering of mortar.

40 Laboratory Tests: Petrographic Examination & Absorption Tests A polarizing light microscope is used to view the sample and help analyze the mortar. Brick samples are heating and boiled to analyze their absorption rates

41 Laboratory Tests: Brick & Prism Compressive Strength Matching the existing brick strength is important to the future integrity of the entire wall. Similar to the brick compressive test, this test analyzes a portion of the masonry wall including the mortar.

42 PROJECT OVERVIEW

43 Significance Local significance industry/commerce Link to agricultural industry Coming of age of livestock feed industry Best remaining example of pre WWII livestock

44 Character Defining Features Large main block flanked by set back wings Dominance of primary facade

45 Character Defining Features Repetitive segmented & corbeled semicircular arches Large window openings, banding, corbeled parapets

46 Character Defining Features Large interior space

47 History Constructed as US Sugar Beet Co. Sold at auction May 1924 / fall 1929

48 History James Garver Feed & Storage 1975 Garver Feed & Supply Co.

49 History Madison Landmark 1994 Business closed October 1997.

50 Preservation Principles National Park Service Standards Cogent link to the past Stabilization

51 STRUCTURAL & ENVELOPE EXISTING CONDITION

52 Typical Building Envelope findings Rising damp Deteriorated sills Freeze thaw damage Gaps within mortar bed Failing roofing Non-weather tight openings Deteriorated parapets Spalling masonry Failing mortar

53 Rising damp Masonry wall acts like a sponge leading to faliiling mortar and spalled brick. (A) (B) Also note the distinctive tide mark. (B) (A)

54 Rising damp Failed roofing causes rising damp issues on the interior. Failing mortar & spalled brick.(a) Also note the distinctive tide mark. (B) (B) (A)

55 Deteriorated sills Typical sill condition Loose mortar (A) (A) (B) Fractured brick (B)

56 Freeze thaw damage First two interior brick courses experience freeze thaw. One full brick (2-2/3 ) concealed within solid ice. (A) (B) (A) Snow is 14 inches at deepest point.(b)

57 Freeze thaw damage Exposed window sill.(a) (B) (A) Exposed top of wall.(b)

58 Deteriorated parapets

59 Spalling masonry Fracturing concrete band.(a) (A) (B) Spalled brick.(b)

60 Failing mortar

61 Gaps within mortar bed

62 Failing roofing

63 Non-weather tight openings

64 Atypical Building Envelope findings Excessive water damage Vegetation within walls

65 Excessive water damage AREA F AREA H

66 Vegetation within walls

67 Typical Structural Findings Wood Roof Deterioration Concrete Roof Deterioration

68 Deteriorated Wood Framing Sheathing Joists Nailers Steel framing supporting the wood framing in most cases was found to be OK

69 Deteriorated Concrete Spalled sections of concrete Holes on Concrete Roof

70 Atypical Structural findings Detrimental Movements Structural Masonry Cracks Bad Lintels Stability Issues Unknown Conditions

71 Detrimental Movements Bowing Bulging Movement related to settlements Movement related to thermal changes

72 Structural Cracks Cracks at Lintels Wall Separation Cracks related to possible settlements

73 Bad Lintels Steel Masonry

74 Stability Issues Tall walls with openings Lack of connection to floor or roof structure

75 Unknown Conditions Significant amount of concealed and inaccessible areas What will we find during repairs, stabilization, and construction?

76 SUMMARIES OF STABILIZATION

77 Stabilization strategies for Structural Issues Roofs, Wood and Concrete Detrimental Movements Structural Masonry Cracks Bad Lintels Stability Issues, Diaphragms, Walls, Columns, Trusses Unknown Conditions D, F, G, H

78 Masonry walls EXTERIOR INTERIOR

79 COST ESTIMATE DEVELOPMENT

80 Estimating Process and Tools Scopes of Work Defined Detailed Quantity Surveys Unusual Conditions Identified Subcontractor Input Segregation by Building Area

81 Cost Evaluation and Considerations Historical Cost Database Subcontractor Input Unit Prices Established Total Project Cost

82 SUMMARY

83 Have a good understanding of the extent of deterioration and therefore probable costs All solvable stabilization issues Implementation could be phased to accommodate budget Stabilization should create opportunities for those interested in the adaptive reuse