進水塔塔背回填抗震設計優化研究與動態響應

曹偉+劉云賀+黨康寧+鄭曉東+陶磊

摘要：為分析塔背不同回填材料與不同回填厚度對進水塔動態響應的影響，建立6種回填材料與4種回填厚度相互組合下的數值試驗模型，對進水塔進行動力分析。對比進水塔關鍵部位的應力與位移發現：回填材料的不同對塔背與回填交界區域應力有一定影響，石渣回填時，此區域應力最大值有很大減小，接觸面應力分布狀態也發生了變化；回填厚度對塔頂位移的影響不大。根據數值試驗的計算結果與分析規律，合理使用石渣回填，設計了一種新的回填型式。此型式下塔背與回填交界區域不在為集中應力發生的部位；接觸面最大應力大幅減小，相同部位的應力值減小；大應力區位置向下偏移，且區域變大、變寬，說明新回填型式改善了進水塔結構的應力狀態，對其安全很有利。將提出的回填方法應用于某泄洪洞進水塔結構中，對比分析了新回填型式與原回填型式兩種情況下此進水塔塔背與回填交界角點應力時程曲線、塔背與回填接觸面應力云圖與損傷云圖。結果表明新回填型式下進水塔與回填接觸面的動態響應得到了很大改善，該方法對進水塔結構的抗震與安全具有重要意義，可供類似工程借鑒。

關鍵詞：進水塔；塔背回填；動態響應；回填優化；時程分析

中圖分類號：TV732 文獻標識碼：A 文章編號：1672-1683（2017）03-0151-07

Abstract：In order to analyze the effects of different backfill materials and different backfill thickness on the dynamic response of intake towers，we set up a numerical test model that combined 6 types of backfill materials and 4 types of backfill thickness，and conducted dynamic analysis of the intake tower.When the rock ballast was filled，the maximum stress of the area was greatly reduced，and the stress distribution of the contact surface was changed；the thickness of backfill had little influence on the displacement of the top of the tower.Based on the calculation results and analysis of the numerical test，a new type of backfill was designed with rational use of rock ballast backfill.For this type，the junction between the tower and the backfill was not in the position of the concentrated stress.The maximum stress of the contact surface was greatly reduced，and the stress value of the same area was reduced.The large-stress area shifted downwards，and the area became larger and wider，indicating that the new type improved the stress state of the intake tower structure，and was beneficial to the safety of the intake tower.The proposed method was applied to the structure of a water intake tower in a flood discharging tunnel.Comparison was made between the new and original backfill types in terms of the stress time-history curve of the junction between the intake tower back and backfill，as well as the stress nephogram and damage nephogram of the contact surface between the intake tower back and backfill.The results showed that the dynamic response of the contact surface between the intake tower and backfill was greatly improved by the new type of backfill.This backfill method is of great significance to earthquake resistance and safety of intake tower structures，and can be used as reference for similar projects.

Key words：intake tower；backfill；dynamic response；backfill optimization；time-history analysis

進水塔是引水、泄水系統的控制性水工建筑物，作為一種高聳建筑物，常常孤立在庫區中，只有塔背的下部與壩體或與邊坡巖體接觸，接觸部位常采用開挖回填的型式進行處理。……