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HomeMy WebLinkAboutSubmittal-Elvis Cruz-Letter from Morningside Civic Association( x I'vIt_}iniit 5lde E 4 Submitted into the pub record for its) h. T � on l 1 City Clerk ivic f- At-chitectitr-al Review Comrnittee \�amrri Brit l Monday, September 17th, 2018 Warren Adams City of Miami Planning and Zoning — Preservation Officer 444 SW 2nd Avenue, 3rd Floor Miami, FL 33130 Subject: Demolition of a Contributing Structure and New Construction 5605 N Bayshore Drive (Morningside Historic District) Dear Mr. Adams, The Morningside Civic Association's Architectural Review Committee (MCA ARC) has been contacted by the owner's representative about the project and provided documents dated 4.17.2018. The Architectural Review Committee does not justify and doesn't support Demolition by Neglect of this Contributing Structure in the Morningside Historical District, We were initially contacted about the project last year, March 24th 2017. We were given a presentation after we visited the property. We communicated to the owner our firm believes about the neighborhood and the property in question, which haven't changed since that meeting. There were code violations posted on the property on April 19th, 2017, and then July 18`h 2017 regarding the property been abandoned and the intentional neglect of the exterior and interior of the structure. The ARC is not looking to discuss the new design in this letter but we also find the application incomplete; the landscape documents were not provided to us, as well as information about the entry gate, The Architectural Review Committee will like to request to the City HEP Board that they exercise all of their powers, including that of all City enforcement agencies and their powers, to prevent the "Demolition by Neglect" of this home. Sincerely, The Architectural Review Committee G�1]l���UL - 1,� �� �,M 0n Submittedinto the pub % record F r ite {s) on City Clerk CHLORIDE TRANSPORT AND REINFORCEMENT CORROSION; There is an enormous amount of literature and research pertaining to this subject matter. What amount of chloride ion content in percent of concrete weight will induce corrosion in the reinforcing steel and how effective will concrete restoration be? A selected few research publications will be referenced in this report to assess the final determination of 5605 North Bayshore Drive along with the chloride test results obtained by "ATC" from the boring samples taken. It should be observed that the samples were taken from the face the building inward and that the range -is from a low of 0.016% to a high of 0,075% by weight of concrete. It is also to be noted that the depth of the samples were taken from I" to 2" into the concrete sample area. Concrete coverage over steel reinforcing in slabs is nominally 3/4" for slabs and 1- 1 /2" for beams and girders if the concrete surface is to be exposed to the weather or in contact with the ground, a protective covering of at least 2" is required. The mechanism by which chlorides initiate corrosion is by locally breaking down the passive film which forms on steel in the highly alkaline concrete pore solution. However the breakdown of passivity requires a certain concentration of chlorides. In good quality Portland cement concrete, steel develops a protective passive layer because of the high alkalinity of the pore solution. In the passive state, the steel corrodes at an insignificantly slow rate, typically of the order of Upm/year. However, chloride ions can break down this passivity and allow the steel to actively corrode at rate several orders of magnitude higher than the passive rate. The critical amount of chloride necessary for the breakdown of the passive film and the onset of active corrosion has been a subject of controversy for many years. Moreover, the amount of chloride which can be tolerated without risk of corrosion is of major interest to all practicing Engineers and most importantly, of the greatest interest in the survivability of 5605 North Bayshore Drive. There are many factors which ultimately contribute to the chloride levels within concrete, atmospheric conditions, water and sand add mixtures and excelerants for the rapid hardening of the concrete. For the purpose of this report, it will be irrelevant as to how the levels of chloride have been reached within the concrete of 5605 North Bayshore Drive. There are two important factors that need to be considered when determining how critical is the corrosion of the steel within concrete. First would be the Page 3 1 12 2120 1 9 Experimental Protocol to Determine the Chloride Threshold Value for Corrosion in Samples Taken from Reinforced Concrete Structures I Protocol Search 9,615 video arftc @&nned ABOUT JoVE FOR LIBRARIANS PUBLISH CED VIDEO JOURNAL ,1TRr;r;,j1(--rl(-)N PROTOCOL RESULTS ASCUSSIOfUMATERIAL IWNLOAD SCIENCE EDUCATION JL1U%,t UIV0 QII.0 GJLIIIIQLIIIIj IIID 1GIIIQII I11IIJ. 0171 VILG IIIG Ly PIUCLIly rely on determining the chloride content at different depths in Submitted into the public the concrete, particularly at the depth of the embedded rncordor it (S) reinforcing steel. A number of reliable and standardized °n City Clerk methods exist to measure this chloride concentration in samples of concrete 8. Comparing the results to 'Ccrit provides the basis for the assessment of corrosion risk, and planning the type and the extent of repair measures. However, this approach requires knowledge of Ccrit. Different international standards and recommendations, as well as text books, stipulate values for Ccri11,3,9.1®,11 These are typically around 0.4% chloride by weight of cement, based on long-term experience or early studies12,13 However, it is well known that the actual resistance against Ccrit of a certain structure or structural member is strongly influenced by the materials used, by the age of the structure, and by exposure history and conditions1.5. Thus, it is generally accepted that experience from one structure should only be applied to other structures with caution. Despite this, it is common engineering practice to use tabulated Ccrit values, independent of the actual structure. This can be explained by the huge scatter of Ccrit in the literature and by the lack of reliable methods to determine Ccrit on-site and in the laboratory5. The approach of using tabulated threshold values in durability assessments is in contrast to structural considerations in condition assessments of aging concrete structures. In the latter case, there exist a number of standardized test methods to determine mechanical properties, such as the strength of the materials in the structure (concrete, reinforcing steel), to be used in the calculations of the structural behavior. CITE THIS CHAPTERS 0:05 Title 0:59 Sampling on the Civil Engineering Structure 2:12 Sample Preparation in the Laboratory In this work, an experimental protocol to determine Ccrit on 3:57 Corrosion https:llwww,jove.com/video/56229/experi menta] -protocol-to-determine-chloride-threshold-value-far 4,34 1122/2019 Experimental Protocol to Determine the Chloride Threshold Value for Corrosion in Samples Taken from Reinforced Concrete Structures I Protocol CSearch 9,615 video artiCt"W%neea ABOUT JOVE FOR LIBRARIANS I1 - BSTRACT INTRODUCTION PROTOCOL RESULTS DISCUSSION MATERIAL +1+, interface, which cannot be representatively mimicked in laboratory -produced samples. At the same time, the accelerated corrosion test in the laboratory permits the reliable determination of Ccrit prior to corrosion initiation on the tested structure; this is a major advantage over all common condition assessment methods that only permit estimating the conditions for corrosion after initiation, i.e., when the structure is already damaged. The protocol yields the statistical distribution of Ccrit for the tested structure. This serves as a basis for probabilistic prediction models for the remaining time to corrosion, which is needed for maintenance planning. This method can potentially be used in material testing of civil infrastructures, similar to established methods used for mechanical testing. INTRODUCTION Corrosion of steel in concrete, triggered by the penetration of chlorides through the concrete, is the most frequent cause of the premature degradation of reinforced and pre -stressed concrete structures, and thus presents one of the most important challenges in civil engineeringt,2°3.4. Industrialized countries typically have a large inventory of aging concrete infrastructures, built in the second half of the last century, and thus with a history of several decades of exposure to marine climate or deicing salts used on roads. Being able to reliably assess the condition of these structures, i.e., the risk for corrosion, forms the basis for planning maintenance work and for infrastructure management, in general. SCIENCE EDUCATION Submitted into the pub is record or it m(s) Z. ti on City Clerk CITE THIS CHAPTERS 0:05 Title 0:59 Sampling on the Civil Engineering Structure 2:12 Sample Preparation in the Laboratory Thin actnhlichmrl nnnrnar-h in onnincsarinn fnr mnnnninn 3:57 Corrosion htips://www.jovc.com/video/56229/experi mental -protocol -to -determine -chloride -threshold -value -for 3,3-1 Submitted into the pub 'c record for i m(s) )t. I I on City Clerk (i) Miami City Code, Section 23-6.2 (i) Demolition by neglect. (f) Demolition by neglect prohibited; affirmative maintenance required. The owner(s) of a property designated historic pursuant to this chapter, which includes a property either individually designated, or designated as a contributing property within a historic district, as defined by this chapter, shall comply with all applicable codes, laws, and regulations governing the maintenance of the property. It is the intention of this section to preserve from deliberate negligence, or inadvertent neglect the exterior features of property designated historic and the interior portions thereof when maintenance is necessary to prevent deterioration and decay of the property. All such properties shall be preserved against such decay and deterioration and shall be free from structural defects through prompt corrections of any of the following defects: a. Facades which may fall or damage the subject property, adjoining property, or injure members of the public. rel Deteriorated or inadequate foundation, defective or deteriorated flooring or floor supports, deteriorated walls, or other vertical structural supports. C. Members of ceilings, roofs, or other horizontal members which sag, split, or buckle due to defective material or deterioration. 11 Deteriorated or ineffective waterproofing of exterior walls, roofs, foundations, or floors, including broken or missing windows or doors. e. Any fault or defect in the property which renders it structurally unsafe, insufficiently protected from weathering, or not properly watertight. Defective or insufficient weather protection which jeopardizes the integrity of exterior or interior walls, roofs, or foundation, including lack of paint or weathering due to lack of paint or protective covering. 9 - Any structure designated historic which is not properly secured under the Florida Building Code or other technical codes and is accessible to the general public; or, any fault or defect on the property designated historic that renders it structurally unsafe or not properly watertight. h. Spalling of the concrete of any portion of the interior or exterior of the structure designated historic. (2) Unreasonable or undue economic hardship. A property owner who believes that application of this section creates an unreasonable or undue economic hardship, as that term is defined by this Submitted into the public ' recordf r it (s) on 1 '_ , 1 I q City Clerk chapter, may apply for a special certificate of appropriateness to the board within 15 days of having notice or knowledge of any defect(s) referred to in this section. The procedure employed by the board shall be the same as for the consideration of a special certificate of appropriateness under this chapter. The board may grant the owner an extension of time to comply with corrective work or limit the scope of the corrective work. (3) Enforcement. a. Notice of administrative enforcement. Enforcement shall be as provided pursuant to Chapter 2, Article X. entitled "Code Enforcement," of the City of Miami Code, as amended. b. Civil actions for injunction and remedial relief; lien on property. In addition to code enforcement remedies, if the property owner fails to take corrective action within the time prescribed, the city may file any civil action ordering the property owner to take corrective actions and the city may seek damages and seek any other relief available under Florida Law. The court may order an injunction providing such remedies if the city proves that the owner has violated this ordinance and such violation threatens the integrity or existence of a designated historic property. In the event that a court order authorizes that the city enter into the property and take corrective action, the cost of the corrective action incurred by the city shall be a municipal special assessment lien against the property. Such lien shall, until fully paid and discharged, be of equal rank and dignity with the lien of ad valorem taxes, and shall be superior in rank and dignity to all other liens, encumbrances. titles, claims in, to or against the real property involved. Such liens may be instituted and enforced pursuant to Chapter 173, Florida Statutes, as amended, or the collection and enforcement of payment thereof may be accomplished by any other method authorized by law. The property owner shall pay all costs of collection, including reasonable attorney's fees, service charges, civil penalties, and liens imposed by virtue of this ordinance.