施工震動對混凝土結構物鋼筋握裹強度之影響試驗及研究

The Test and Stady of the Steel Bond Strength for the Concrete Structures Subject to Constructive Vibration

洪聖偉(SHENG-WEI HUNG)

指導教授 ： 彭添富

國立臺北科技大學/工程學院/土木與防災研究所/碩士(2006年)

摘要

近年來由於生活水準提高，大眾對於生活環境要求愈來愈講究，於住宅方面，除了要住得安心外，更是講就室內方便、美觀等需求，故對老舊房子重新裝修有時必需對次要結構部份（如牆壁、地板等）拆除修建，人力機械（如電動鎚）之震動施工，混凝土結構體強度、耐久性等於設計時之早己達到規範，但拆除修建過程中以是否會影響主要結構物強度，造成握裹應力折損值得探討，本文以試驗研究鋼筋混凝土結構、混凝土及鋼筋分別受施工機具震動後，鋼筋與混凝土間握裹力所受之影響，進行握裹應力折損評估研究。
本試驗依據中國國家標準CNS 11152規定設計試體模擬鋼筋混凝土建築物其內部以電動鎚拆除非結構體時震動到鋼筋及混凝土，試驗分析研究鋼筋混凝土握裹應力強度。試體藉由相同震動頻率及鋼筋尺寸一致下、以各種不同之混凝土強度及不同之震動位置及不同之震動時間等變數，試驗其握裹應力之影響並建立其間之關係曲線圖，以瞭解鋼筋混凝土受到震動後其握裹力是否有折損情況；經由試驗結果顯示，混凝土規劃強度210kgf/cm2者鋼筋受震動時有明顯折損現象，混凝土規劃強度280kgf/cm2以上者，各種震動試驗握裹應力均無明顯折損現象。

關鍵字

握裹力 ； 握裹應力 ； 電動鎚

並列摘要

Recently, with living standard on the rise, people in general have become ever more demanding on the environment in which they live. On the residential front, in addition to comfort living, more attention has been focused on the requirement for interior convenience and blazonry, which invariably leads to household renovation effort. As a result, tearing down or even remodeling effort of secondary structure, such as walls or floors, are deemed inevitable. And thus the question: whether construction-induced vibration from man-operated machine (the like of electric drill for example) could in any way impact the strength of the main structure (which was in full conformance of all rules and regulations at the drawing-board stage, in area such as concrete structure, strength and durability), and whether that renders stress-bond being compromised is a subject worth exploring. This literature embarks on testing the structure of reinforcement concrete, as well as the impact to bonding between reinforcement and concrete after taking into account the construction vibration on concrete and reinforcement respectively, to assess the extent of compromise on bond stress.
This test, designing testing object in accordance with the Chinese National Standard CNS 11152 regulation, simulates construction vibration (from knocking down non-structural parts) on reinforcement and concrete in reinforcement concrete building, and analyzing and researching bond stress density on reinforcement concrete. Given the same vibrating frequency and similar reinforcement size, testing object tested the impact of bond stress under various concrete densities, vibrating positions and vibrating durations, and mapping its correlations into a curve chart, to help understand whether bonding of reinforcement concrete is compromised after the effect of vibration factored in. As indicated by the test result, concrete of planned density 210kgf/cm2 suffered obvious damage on vibration, whereas concrete of planned density over 210kgf/cm2 didn’t seem to suffer in bond stress from various vibrations.

並列關鍵字

Bond ； Bond Stress ； Electronic Hammer

參考文獻

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