ブックタイトル「煉瓦造建造物の保存と修復」英語版

概要

「煉瓦造建造物の保存と修復」英語版

5. Preventive Measures against Deterioration and DamageFrom the issues clarified regarding brick deterioration and damage in Section 2, preservation cases that can be referred to inconsidering future restoration of brick masonry structures will be introduced fn 17 .5-1. Controlling water ingress【Case 1：Former Temiya Railway Facilities / Engine Shed】Name：Former Temiya Railway Facilities /Engine Shed No.3Construction year：Meiji 18（1885）Structure：Brick masonry, iron roofBuilding area 118.57m2Location：1 Chome, Temiya, Otaru City,HokkaidoProprietor：Otaru CityDesignation/Registration（date）：Important Cultural Property（2001.11.14）Restoration period：2006 ? 2009photo 5-1Former Temiya Railway Facilities? Planning of restorationBefore restoration, there were numerous cracks spreadingover a wide area on the inner walls (photo 5-4).An investigation into its cause revealed that the level ofunderground water was high and freeze-thaw damage hadoccurred on brick wall surfaces that had absorbed waterfrom the ground. Inner walls were finished with mortar andthe absorbed water froze in the gap between the brick walland mortar finish, pushing the mortar outwards resulting incracks where freezing had occurred. Therefore, to controlwater absorption from underground, brick joints in areasclose to the ground surface were repointed with mortarwith water repelling properties fn 16 . In this collection ofpreservation efforts, restoration involving joint repointingwill be introduced (figure 5-1) fn 17 .? Outline of restorationOn the reinforced concrete foundations, mortar hadrun off as ground water entered the structure and formed"honeycombs”where cement and aggregate becameseparated. Therefore, waterproofing mortar was appliedon the foundation’s surface. Also, in order to prevent waterfrom entering the brick walls, one joint course at the base ofthe wall was repointed using non-shrinkage cement fn 18 .・MaterialsWaterproofing agent：Taiheiyo U-LOX cement (non-shrinkage grout (fluiditytype), Taiheiyo Materials Corporation)Sealing agent：Erewhon #300 (Quick setting high performance cutoffmortar (Kaseikogyo Co., Ltd,))・Steps in restoration1 Boring holes into the brick wall (photo 5-2)At 500mm intervals in the horizontal direction, holes weremade into the joint for inserting a wire saw blade.photo 5-2 Boring holes（photo provided by：Japanese Association forConservation of Architectural Monuments）2 Removal of joint pointing material (photo 5-3)A wire saw was inserted into the hole and a length of500mm of pointing was removed. The blade of the wiresaw chosen was 6mm to 9mm in diameter to match thejoint width.photo 5-3 Cutting operation by wire saw（photo provided by：JapaneseAssociation for Conservation of Architectural Monuments）3 Cleaning areas from which pointing was removed (photo 5-6)94Chapter 6A Collection of Case Studies of Preservation and Restoration of Brick Masonry Structures