【正文】 KN（ ）或 ,與此相關的屋頂偏差率為 。 圖 14b 所示的 是偏差率 dr，是在結構物的兩處高度處測量出來的，結果顯示的是兩層有相同的偏差值，這是由于構造橋對結構物的總的反映的突出貢獻。結構物的這個位移特征表示，給定一個 Dr 值，偏差值在數(shù)量上相似。 周期側向荷載以屋頂偏差率 以及相應的基礎剪力為 462KN 或 終止。在這個側向位移的高度處，在第一層墻的端部的縱筋的屈服點超過了，這導致了沿著頂部厚板 墻的接頭的裂開處的顯著的超出平面的位移。圖 14a 也顯示在測試過程中一些可觀察重要的構件。下面介紹的是在結構物的測試過程中可觀察的破壞構件的小結。 墻的破壞最初 是由混凝土蓋板的倒塌以及在第一樓層墻端的縱筋的屈服造成的，這些構件的 Dr 值為 ，縱筋的屈服是在這些臨界面的混凝土的倒塌后立刻發(fā)生的。 圖 15， 16 所示的是測試結束時側向框架的破壞的總的概括。圖 18 提供的是測試結束時第一樓層墻端的縱筋屈服時的詳細情況，圖 1518 說明了測試結束時，柱，梁柱，梁 柱接頭處可觀察到的破壞情況明顯地比墻要小。 在結構構件的臨界面中的塑料合頁的形成，比如在第一樓層柱和墻的末端，在梁的末端，尤其在達到最大基礎剪力時被觀測到了。 剛開始裂開和折斷時，在厚板的頂部和板 墻接頭處的 WWR 被觀測出的值的范圍是從 .。 4到 ，測試結束時，每一樓層的裂縫形式，在 Rodriguez 和 Blandon的相關文章中有介紹，如這兒所見，在厚板頂部 ,尤其是板 墻接頭處的鋼絲的折 5 斷可以觀察到，接頭出折斷的寬度是 15mm 和 30mm。 圖 19 所示的是結構物的失效模式，描述的是微弱的梁 強大的強的失效機理，該假定的機理以可觀察的塑料合頁的安置為基礎。 在一些柱，梁，墻的臨界截面處的潛在的塑料合頁的曲率可通過電位計的讀數(shù)計算出來的一些截面的張應力可以從電阻應變測量儀上得到。關于預制梁的詳細的測量的討論在相關的文 章中有陳述。 從這些測量結果可推斷出側向框架中的梁柱，梁墻連接設計在做為傳統(tǒng)的現(xiàn)澆連接的意義上是成功的，然而中間框架中梁柱接頭不是這樣，正如以前提到的，梁底部鋼筋沒有符合規(guī)范所要求的發(fā)展長度。 Tests on a HalfScale TwoStory SeismicResisting Precast Concrete Building This paper describes experimental studies on the seismic behavior and design of precast concrete buildings. A halfscale twostory precast concrete building incorporating a dual system and representing a parking structure in Mexico City was investigated. The structure was tested up to failure in a laboratory under simulated seismic loading. In some of the beamtocolumn joints, the bottom longitudinal bars of the beam were purposely undeveloped due to dimensional constraints. Emphasis is given in the study on the evaluation of the observed global behavior of the test structure. This behavior showed that the walls of the test structure controlled the force path mechanism and significantly reduced the lateral deformation demands in the precast frames. Seismic design criteria and code implications for precast concrete structures resulting from this research are discussed. The end result of this research is that a better understanding of the structural behavior of this type of building has been gained results of simulated seismic load tests of a two story precast concrete building constructed with precast concrete elements that are used in Mexico are described herein. The structural system chosen in the test structure is the so called dual type, defined as the bination of structural walls and beamtocolumn frames. Connections between precast beams and columns in the test structure are of the window type. This type of construction is typically used in low and medium rise buildings in which columns are connected with windows at each story level. These windows contain the top and bottom 6 reinforcement. Fig. 1 shows this type of construction for a mercial building in Mexico City. In most precast concrete frames such as those shown in Fig, 1, longitudinal beam bottom bars are not fully developed due to constraints imposed by the dimensions of file columns in beamtocolumn joints. In an effort to overe this deficiency, and as described later, some practicing engineers in Mexico design these joints by providing hoops around the hooks of that reinforcement in order to achieve its required continuity. However, this practice is not covered in the ACI Building Code (ACI31802), nor in the Mexico City Building Code (MCBC, 1993). Part of this research was done to address this issue. The objectives of this research were Io evaluate the observed behavior of a precast concrete structures in the laboratory and to propose the use of precast structural elements or precast structures with both an acceptable level of expected seismic performance and appealing features from the viewpoint of construction Emphasis is given in this paper on the global behavior of the test structure. In the second part of this research which gill be presented in a panion paper, the observed behavior of connections between precast elements in the test structure, as well as the behavior of the precast floor system will be discussed in detail. Structural and non structural damages observed in buildings during past earthquakes throughout the world have shown the importance of controlling lateral displacement in structures to reduce building damage during earth quakes. It is also relevant to mention that there are several cases of structures in moderate earthquakes in which the observed damage in nonstructural elements in buildings was considerable even though the structural elements showed little or no damage. This behavior is also related Io excessive lateral displacement demands in the structure. To minimize seismic damage during earthquakes, the above discussion suggests the convenience of using a structural system capable of controlling lateral displacements in structures. A solution of this type is the socalled dual system. Studies by Paulay and Priestley4 on the seismic response of dual systems have shown that the presence of walls reduce the dynamic moment demands in structural elements 7 in the frame subsystem. Also in conjunction with shake table tests conducted on a castinplace reinforced concrete dual system. Bertero5 has shown the potential of the dual system, in achieving excellent seismic behavior [n this investigation, the dual system is applied to the case of precast concrete structures. DUCTILITY DEMAND IN DUAL SYSTEMS